| Message ID | 20230401094658.11146-1-vbabka@suse.cz (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm: remove all the slab allocators | expand |
On Sat, Apr 01, 2023 at 11:46:58AM +0200, Vlastimil Babka wrote: > As the SLOB removal is on track and the SLAB removal is planned, I have > realized - why should we stop there and not remove also SLUB? What's a > slab allocator good for in 2023? The RAM sizes are getting larger and > the modules cheaper [1]. The object constructor trick was perhaps > interesting in 1994, but not with contemporary CPUs. So all the slab > allocator does today is just adding an unnecessary layer of complexity > over the page allocator. > > Thus, with this patch, all three slab allocators are removed, and only a > layer that passes everything to the page allocator remains in the slab.h > and mm/slab_common.c files. This will allow users to gradually > transition away and use the page allocator directly. To summarize the > advantages: > > - Less code to maintain: over 13k lines are removed by this patch, and > more could be removed if I wast^Wspent more time on this, and later as > users are transitioned from the legacy layer. This no longer needs a > separate subsystem so remove it from MAINTAINERS (I hope I can keep the > kernel.org account anyway, though). > > - Simplified MEMCG_KMEM accounting: while I was lazy and just marked it > BROKEN in this patch, it should be trivial to use the page memcg > accounting now that we use the page allocator. The per-object > accounting went through several iterations in the past and was always > complex and added overhead. Page accounting is much simpler by > comparison. > > - Simplified KASAN and friends: also was lazy in this patch so they > can't be enabled but should be easy to fix up and work just on the > page level. > > - Simpler debugging: just use debug_pagealloc=on, no need to look up the > exact syntax of the absurdly complex slub_debug parameter. > > - Speed: didn't measure, but for the page allocator we have pcplists, so > it should scale just fine. No need for the crazy SLUB's cmpxchg_double() > craziness. Maybe that thing could be now removed too? Yeah I can see > just two remaining users. > > Any downsides? Let's look at memory usage after virtme boot: > > Before (with SLUB): > Slab: 26304 kB > > After: > Slab: 295592 kB > > Well, that's not so bad, see [1]. > > [1] https://www.theregister.com/2023/03/29/dram_prices_crash/ > --- > MAINTAINERS | 15 - > include/linux/slab.h | 211 +- > include/linux/slab_def.h | 124 - > include/linux/slub_def.h | 198 -- > init/Kconfig | 2 +- > mm/Kconfig | 134 +- > mm/Makefile | 10 - > mm/slab.c | 4046 ------------------------ > mm/slab.h | 426 --- > mm/slab_common.c | 876 ++--- > mm/slob.c | 757 ----- > mm/slub.c | 6506 -------------------------------------- > 12 files changed, 228 insertions(+), 13077 deletions(-) > delete mode 100644 include/linux/slab_def.h > delete mode 100644 include/linux/slub_def.h > delete mode 100644 mm/slab.c > delete mode 100644 mm/slob.c > delete mode 100644 mm/slub.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 1dc8bd26b6cf..40b05ad03cd0 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -19183,21 +19183,6 @@ F: drivers/irqchip/irq-sl28cpld.c > F: drivers/pwm/pwm-sl28cpld.c > F: drivers/watchdog/sl28cpld_wdt.c > > -SLAB ALLOCATOR > -M: Christoph Lameter <cl@linux.com> > -M: Pekka Enberg <penberg@kernel.org> > -M: David Rientjes <rientjes@google.com> > -M: Joonsoo Kim <iamjoonsoo.kim@lge.com> > -M: Andrew Morton <akpm@linux-foundation.org> > -M: Vlastimil Babka <vbabka@suse.cz> > -R: Roman Gushchin <roman.gushchin@linux.dev> > -R: Hyeonggon Yoo <42.hyeyoo@gmail.com> > -L: linux-mm@kvack.org > -S: Maintained > -T: git git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab.git > -F: include/linux/sl?b*.h > -F: mm/sl?b* > - > SLCAN CAN NETWORK DRIVER > M: Dario Binacchi <dario.binacchi@amarulasolutions.com> > L: linux-can@vger.kernel.org > diff --git a/include/linux/slab.h b/include/linux/slab.h > index 45af70315a94..61602d54b1d0 100644 > --- a/include/linux/slab.h > +++ b/include/linux/slab.h > @@ -140,13 +140,14 @@ > > /* The following flags affect the page allocator grouping pages by mobility */ > /* Objects are reclaimable */ > -#ifndef CONFIG_SLUB_TINY > #define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U) > -#else > -#define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0) > -#endif > #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */ > > +#define KMALLOC_NOT_NORMAL_BITS \ > + (__GFP_RECLAIMABLE | \ > + (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ > + (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) > + > /* > * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests. > * > @@ -278,38 +279,11 @@ static inline unsigned int arch_slab_minalign(void) > * Kmalloc array related definitions > */ > > -#ifdef CONFIG_SLAB > -/* > - * SLAB and SLUB directly allocates requests fitting in to an order-1 page > - * (PAGE_SIZE*2). Larger requests are passed to the page allocator. > - */ > -#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) > -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > -#ifndef KMALLOC_SHIFT_LOW > -#define KMALLOC_SHIFT_LOW 5 > -#endif > -#endif > - > -#ifdef CONFIG_SLUB > -#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) > -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > -#ifndef KMALLOC_SHIFT_LOW > -#define KMALLOC_SHIFT_LOW 3 > -#endif > -#endif > - > -#ifdef CONFIG_SLOB > -/* > - * SLOB passes all requests larger than one page to the page allocator. > - * No kmalloc array is necessary since objects of different sizes can > - * be allocated from the same page. > - */ > #define KMALLOC_SHIFT_HIGH PAGE_SHIFT > #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > #ifndef KMALLOC_SHIFT_LOW > #define KMALLOC_SHIFT_LOW 3 > #endif > -#endif > > /* Maximum allocatable size */ > #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX) > @@ -336,130 +310,6 @@ static inline unsigned int arch_slab_minalign(void) > #define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \ > (KMALLOC_MIN_SIZE) : 16) > > -/* > - * Whenever changing this, take care of that kmalloc_type() and > - * create_kmalloc_caches() still work as intended. > - * > - * KMALLOC_NORMAL can contain only unaccounted objects whereas KMALLOC_CGROUP > - * is for accounted but unreclaimable and non-dma objects. All the other > - * kmem caches can have both accounted and unaccounted objects. > - */ > -enum kmalloc_cache_type { > - KMALLOC_NORMAL = 0, > -#ifndef CONFIG_ZONE_DMA > - KMALLOC_DMA = KMALLOC_NORMAL, > -#endif > -#ifndef CONFIG_MEMCG_KMEM > - KMALLOC_CGROUP = KMALLOC_NORMAL, > -#endif > -#ifdef CONFIG_SLUB_TINY > - KMALLOC_RECLAIM = KMALLOC_NORMAL, > -#else > - KMALLOC_RECLAIM, > -#endif > -#ifdef CONFIG_ZONE_DMA > - KMALLOC_DMA, > -#endif > -#ifdef CONFIG_MEMCG_KMEM > - KMALLOC_CGROUP, > -#endif > - NR_KMALLOC_TYPES > -}; > - > -#ifndef CONFIG_SLOB > -extern struct kmem_cache * > -kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1]; > - > -/* > - * Define gfp bits that should not be set for KMALLOC_NORMAL. > - */ > -#define KMALLOC_NOT_NORMAL_BITS \ > - (__GFP_RECLAIMABLE | \ > - (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ > - (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) > - > -static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) > -{ > - /* > - * The most common case is KMALLOC_NORMAL, so test for it > - * with a single branch for all the relevant flags. > - */ > - if (likely((flags & KMALLOC_NOT_NORMAL_BITS) == 0)) > - return KMALLOC_NORMAL; > - > - /* > - * At least one of the flags has to be set. Their priorities in > - * decreasing order are: > - * 1) __GFP_DMA > - * 2) __GFP_RECLAIMABLE > - * 3) __GFP_ACCOUNT > - */ > - if (IS_ENABLED(CONFIG_ZONE_DMA) && (flags & __GFP_DMA)) > - return KMALLOC_DMA; > - if (!IS_ENABLED(CONFIG_MEMCG_KMEM) || (flags & __GFP_RECLAIMABLE)) > - return KMALLOC_RECLAIM; > - else > - return KMALLOC_CGROUP; > -} > - > -/* > - * Figure out which kmalloc slab an allocation of a certain size > - * belongs to. > - * 0 = zero alloc > - * 1 = 65 .. 96 bytes > - * 2 = 129 .. 192 bytes > - * n = 2^(n-1)+1 .. 2^n > - * > - * Note: __kmalloc_index() is compile-time optimized, and not runtime optimized; > - * typical usage is via kmalloc_index() and therefore evaluated at compile-time. > - * Callers where !size_is_constant should only be test modules, where runtime > - * overheads of __kmalloc_index() can be tolerated. Also see kmalloc_slab(). > - */ > -static __always_inline unsigned int __kmalloc_index(size_t size, > - bool size_is_constant) > -{ > - if (!size) > - return 0; > - > - if (size <= KMALLOC_MIN_SIZE) > - return KMALLOC_SHIFT_LOW; > - > - if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96) > - return 1; > - if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192) > - return 2; > - if (size <= 8) return 3; > - if (size <= 16) return 4; > - if (size <= 32) return 5; > - if (size <= 64) return 6; > - if (size <= 128) return 7; > - if (size <= 256) return 8; > - if (size <= 512) return 9; > - if (size <= 1024) return 10; > - if (size <= 2 * 1024) return 11; > - if (size <= 4 * 1024) return 12; > - if (size <= 8 * 1024) return 13; > - if (size <= 16 * 1024) return 14; > - if (size <= 32 * 1024) return 15; > - if (size <= 64 * 1024) return 16; > - if (size <= 128 * 1024) return 17; > - if (size <= 256 * 1024) return 18; > - if (size <= 512 * 1024) return 19; > - if (size <= 1024 * 1024) return 20; > - if (size <= 2 * 1024 * 1024) return 21; > - > - if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant) > - BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()"); > - else > - BUG(); > - > - /* Will never be reached. Needed because the compiler may complain */ > - return -1; > -} > -static_assert(PAGE_SHIFT <= 20); > -#define kmalloc_index(s) __kmalloc_index(s, true) > -#endif /* !CONFIG_SLOB */ > - > void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __alloc_size(1); > > /** > @@ -567,57 +417,15 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) __assume_page_align > * Try really hard to succeed the allocation but fail > * eventually. > */ > -#ifndef CONFIG_SLOB > -static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) > -{ > - if (__builtin_constant_p(size) && size) { > - unsigned int index; > - > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large(size, flags); > - > - index = kmalloc_index(size); > - return kmalloc_trace( > - kmalloc_caches[kmalloc_type(flags)][index], > - flags, size); > - } > - return __kmalloc(size, flags); > -} > -#else > static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) > { > - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large(size, flags); > - > - return __kmalloc(size, flags); > + return kmalloc_large(size, flags); > } > -#endif > > -#ifndef CONFIG_SLOB > static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) > { > - if (__builtin_constant_p(size) && size) { > - unsigned int index; > - > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large_node(size, flags, node); > - > - index = kmalloc_index(size); > - return kmalloc_node_trace( > - kmalloc_caches[kmalloc_type(flags)][index], > - flags, node, size); > - } > - return __kmalloc_node(size, flags, node); > + return kmalloc_large_node(size, flags, node); > } > -#else > -static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) > -{ > - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large_node(size, flags, node); > - > - return __kmalloc_node(size, flags, node); > -} > -#endif > > /** > * kmalloc_array - allocate memory for an array. > @@ -785,12 +593,7 @@ size_t kmalloc_size_roundup(size_t size); > > void __init kmem_cache_init_late(void); > > -#if defined(CONFIG_SMP) && defined(CONFIG_SLAB) > -int slab_prepare_cpu(unsigned int cpu); > -int slab_dead_cpu(unsigned int cpu); > -#else > #define slab_prepare_cpu NULL > #define slab_dead_cpu NULL > -#endif > > #endif /* _LINUX_SLAB_H */ > diff --git a/include/linux/slab_def.h b/include/linux/slab_def.h > deleted file mode 100644 > index a61e7d55d0d3..000000000000 > --- a/include/linux/slab_def.h > +++ /dev/null > @@ -1,124 +0,0 @@ > -/* SPDX-License-Identifier: GPL-2.0 */ > -#ifndef _LINUX_SLAB_DEF_H > -#define _LINUX_SLAB_DEF_H > - > -#include <linux/kfence.h> > -#include <linux/reciprocal_div.h> > - > -/* > - * Definitions unique to the original Linux SLAB allocator. > - */ > - > -struct kmem_cache { > - struct array_cache __percpu *cpu_cache; > - > -/* 1) Cache tunables. Protected by slab_mutex */ > - unsigned int batchcount; > - unsigned int limit; > - unsigned int shared; > - > - unsigned int size; > - struct reciprocal_value reciprocal_buffer_size; > -/* 2) touched by every alloc & free from the backend */ > - > - slab_flags_t flags; /* constant flags */ > - unsigned int num; /* # of objs per slab */ > - > -/* 3) cache_grow/shrink */ > - /* order of pgs per slab (2^n) */ > - unsigned int gfporder; > - > - /* force GFP flags, e.g. GFP_DMA */ > - gfp_t allocflags; > - > - size_t colour; /* cache colouring range */ > - unsigned int colour_off; /* colour offset */ > - unsigned int freelist_size; > - > - /* constructor func */ > - void (*ctor)(void *obj); > - > -/* 4) cache creation/removal */ > - const char *name; > - struct list_head list; > - int refcount; > - int object_size; > - int align; > - > -/* 5) statistics */ > -#ifdef CONFIG_DEBUG_SLAB > - unsigned long num_active; > - unsigned long num_allocations; > - unsigned long high_mark; > - unsigned long grown; > - unsigned long reaped; > - unsigned long errors; > - unsigned long max_freeable; > - unsigned long node_allocs; > - unsigned long node_frees; > - unsigned long node_overflow; > - atomic_t allochit; > - atomic_t allocmiss; > - atomic_t freehit; > - atomic_t freemiss; > - > - /* > - * If debugging is enabled, then the allocator can add additional > - * fields and/or padding to every object. 'size' contains the total > - * object size including these internal fields, while 'obj_offset' > - * and 'object_size' contain the offset to the user object and its > - * size. > - */ > - int obj_offset; > -#endif /* CONFIG_DEBUG_SLAB */ > - > -#ifdef CONFIG_KASAN_GENERIC > - struct kasan_cache kasan_info; > -#endif > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > - unsigned int *random_seq; > -#endif > - > -#ifdef CONFIG_HARDENED_USERCOPY > - unsigned int useroffset; /* Usercopy region offset */ > - unsigned int usersize; /* Usercopy region size */ > -#endif > - > - struct kmem_cache_node *node[MAX_NUMNODES]; > -}; > - > -static inline void *nearest_obj(struct kmem_cache *cache, const struct slab *slab, > - void *x) > -{ > - void *object = x - (x - slab->s_mem) % cache->size; > - void *last_object = slab->s_mem + (cache->num - 1) * cache->size; > - > - if (unlikely(object > last_object)) > - return last_object; > - else > - return object; > -} > - > -/* > - * We want to avoid an expensive divide : (offset / cache->size) > - * Using the fact that size is a constant for a particular cache, > - * we can replace (offset / cache->size) by > - * reciprocal_divide(offset, cache->reciprocal_buffer_size) > - */ > -static inline unsigned int obj_to_index(const struct kmem_cache *cache, > - const struct slab *slab, void *obj) > -{ > - u32 offset = (obj - slab->s_mem); > - return reciprocal_divide(offset, cache->reciprocal_buffer_size); > -} > - > -static inline int objs_per_slab(const struct kmem_cache *cache, > - const struct slab *slab) > -{ > - if (is_kfence_address(slab_address(slab))) > - return 1; > - return cache->num; > -} > - > -#endif /* _LINUX_SLAB_DEF_H */ > diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h > deleted file mode 100644 > index f6df03f934e5..000000000000 > --- a/include/linux/slub_def.h > +++ /dev/null > @@ -1,198 +0,0 @@ > -/* SPDX-License-Identifier: GPL-2.0 */ > -#ifndef _LINUX_SLUB_DEF_H > -#define _LINUX_SLUB_DEF_H > - > -/* > - * SLUB : A Slab allocator without object queues. > - * > - * (C) 2007 SGI, Christoph Lameter > - */ > -#include <linux/kfence.h> > -#include <linux/kobject.h> > -#include <linux/reciprocal_div.h> > -#include <linux/local_lock.h> > - > -enum stat_item { > - ALLOC_FASTPATH, /* Allocation from cpu slab */ > - ALLOC_SLOWPATH, /* Allocation by getting a new cpu slab */ > - FREE_FASTPATH, /* Free to cpu slab */ > - FREE_SLOWPATH, /* Freeing not to cpu slab */ > - FREE_FROZEN, /* Freeing to frozen slab */ > - FREE_ADD_PARTIAL, /* Freeing moves slab to partial list */ > - FREE_REMOVE_PARTIAL, /* Freeing removes last object */ > - ALLOC_FROM_PARTIAL, /* Cpu slab acquired from node partial list */ > - ALLOC_SLAB, /* Cpu slab acquired from page allocator */ > - ALLOC_REFILL, /* Refill cpu slab from slab freelist */ > - ALLOC_NODE_MISMATCH, /* Switching cpu slab */ > - FREE_SLAB, /* Slab freed to the page allocator */ > - CPUSLAB_FLUSH, /* Abandoning of the cpu slab */ > - DEACTIVATE_FULL, /* Cpu slab was full when deactivated */ > - DEACTIVATE_EMPTY, /* Cpu slab was empty when deactivated */ > - DEACTIVATE_TO_HEAD, /* Cpu slab was moved to the head of partials */ > - DEACTIVATE_TO_TAIL, /* Cpu slab was moved to the tail of partials */ > - DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */ > - DEACTIVATE_BYPASS, /* Implicit deactivation */ > - ORDER_FALLBACK, /* Number of times fallback was necessary */ > - CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */ > - CMPXCHG_DOUBLE_FAIL, /* Number of times that cmpxchg double did not match */ > - CPU_PARTIAL_ALLOC, /* Used cpu partial on alloc */ > - CPU_PARTIAL_FREE, /* Refill cpu partial on free */ > - CPU_PARTIAL_NODE, /* Refill cpu partial from node partial */ > - CPU_PARTIAL_DRAIN, /* Drain cpu partial to node partial */ > - NR_SLUB_STAT_ITEMS }; > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * When changing the layout, make sure freelist and tid are still compatible > - * with this_cpu_cmpxchg_double() alignment requirements. > - */ > -struct kmem_cache_cpu { > - void **freelist; /* Pointer to next available object */ > - unsigned long tid; /* Globally unique transaction id */ > - struct slab *slab; /* The slab from which we are allocating */ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - struct slab *partial; /* Partially allocated frozen slabs */ > -#endif > - local_lock_t lock; /* Protects the fields above */ > -#ifdef CONFIG_SLUB_STATS > - unsigned stat[NR_SLUB_STAT_ITEMS]; > -#endif > -}; > -#endif /* CONFIG_SLUB_TINY */ > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -#define slub_percpu_partial(c) ((c)->partial) > - > -#define slub_set_percpu_partial(c, p) \ > -({ \ > - slub_percpu_partial(c) = (p)->next; \ > -}) > - > -#define slub_percpu_partial_read_once(c) READ_ONCE(slub_percpu_partial(c)) > -#else > -#define slub_percpu_partial(c) NULL > - > -#define slub_set_percpu_partial(c, p) > - > -#define slub_percpu_partial_read_once(c) NULL > -#endif // CONFIG_SLUB_CPU_PARTIAL > - > -/* > - * Word size structure that can be atomically updated or read and that > - * contains both the order and the number of objects that a slab of the > - * given order would contain. > - */ > -struct kmem_cache_order_objects { > - unsigned int x; > -}; > - > -/* > - * Slab cache management. > - */ > -struct kmem_cache { > -#ifndef CONFIG_SLUB_TINY > - struct kmem_cache_cpu __percpu *cpu_slab; > -#endif > - /* Used for retrieving partial slabs, etc. */ > - slab_flags_t flags; > - unsigned long min_partial; > - unsigned int size; /* The size of an object including metadata */ > - unsigned int object_size;/* The size of an object without metadata */ > - struct reciprocal_value reciprocal_size; > - unsigned int offset; /* Free pointer offset */ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - /* Number of per cpu partial objects to keep around */ > - unsigned int cpu_partial; > - /* Number of per cpu partial slabs to keep around */ > - unsigned int cpu_partial_slabs; > -#endif > - struct kmem_cache_order_objects oo; > - > - /* Allocation and freeing of slabs */ > - struct kmem_cache_order_objects min; > - gfp_t allocflags; /* gfp flags to use on each alloc */ > - int refcount; /* Refcount for slab cache destroy */ > - void (*ctor)(void *); > - unsigned int inuse; /* Offset to metadata */ > - unsigned int align; /* Alignment */ > - unsigned int red_left_pad; /* Left redzone padding size */ > - const char *name; /* Name (only for display!) */ > - struct list_head list; /* List of slab caches */ > -#ifdef CONFIG_SYSFS > - struct kobject kobj; /* For sysfs */ > -#endif > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - unsigned long random; > -#endif > - > -#ifdef CONFIG_NUMA > - /* > - * Defragmentation by allocating from a remote node. > - */ > - unsigned int remote_node_defrag_ratio; > -#endif > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > - unsigned int *random_seq; > -#endif > - > -#ifdef CONFIG_KASAN_GENERIC > - struct kasan_cache kasan_info; > -#endif > - > -#ifdef CONFIG_HARDENED_USERCOPY > - unsigned int useroffset; /* Usercopy region offset */ > - unsigned int usersize; /* Usercopy region size */ > -#endif > - > - struct kmem_cache_node *node[MAX_NUMNODES]; > -}; > - > -#if defined(CONFIG_SYSFS) && !defined(CONFIG_SLUB_TINY) > -#define SLAB_SUPPORTS_SYSFS > -void sysfs_slab_unlink(struct kmem_cache *); > -void sysfs_slab_release(struct kmem_cache *); > -#else > -static inline void sysfs_slab_unlink(struct kmem_cache *s) > -{ > -} > -static inline void sysfs_slab_release(struct kmem_cache *s) > -{ > -} > -#endif > - > -void *fixup_red_left(struct kmem_cache *s, void *p); > - > -static inline void *nearest_obj(struct kmem_cache *cache, const struct slab *slab, > - void *x) { > - void *object = x - (x - slab_address(slab)) % cache->size; > - void *last_object = slab_address(slab) + > - (slab->objects - 1) * cache->size; > - void *result = (unlikely(object > last_object)) ? last_object : object; > - > - result = fixup_red_left(cache, result); > - return result; > -} > - > -/* Determine object index from a given position */ > -static inline unsigned int __obj_to_index(const struct kmem_cache *cache, > - void *addr, void *obj) > -{ > - return reciprocal_divide(kasan_reset_tag(obj) - addr, > - cache->reciprocal_size); > -} > - > -static inline unsigned int obj_to_index(const struct kmem_cache *cache, > - const struct slab *slab, void *obj) > -{ > - if (is_kfence_address(obj)) > - return 0; > - return __obj_to_index(cache, slab_address(slab), obj); > -} > - > -static inline int objs_per_slab(const struct kmem_cache *cache, > - const struct slab *slab) > -{ > - return slab->objects; > -} > -#endif /* _LINUX_SLUB_DEF_H */ > diff --git a/init/Kconfig b/init/Kconfig > index 1fb5f313d18f..45be2eedf75c 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -973,7 +973,7 @@ config MEMCG > > config MEMCG_KMEM > bool > - depends on MEMCG && !SLOB > + depends on MEMCG && BROKEN > default y > > config BLK_CGROUP > diff --git a/mm/Kconfig b/mm/Kconfig > index 4751031f3f05..f07e81bca39e 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -210,134 +210,9 @@ config ZSMALLOC_CHAIN_SIZE > > For more information, see zsmalloc documentation. > > -menu "SLAB allocator options" > - > -choice > - prompt "Choose SLAB allocator" > - default SLUB > - help > - This option allows to select a slab allocator. > - > -config SLAB > - bool "SLAB" > - depends on !PREEMPT_RT > - select HAVE_HARDENED_USERCOPY_ALLOCATOR > - help > - The regular slab allocator that is established and known to work > - well in all environments. It organizes cache hot objects in > - per cpu and per node queues. > - > -config SLUB > - bool "SLUB (Unqueued Allocator)" > - select HAVE_HARDENED_USERCOPY_ALLOCATOR > - help > - SLUB is a slab allocator that minimizes cache line usage > - instead of managing queues of cached objects (SLAB approach). > - Per cpu caching is realized using slabs of objects instead > - of queues of objects. SLUB can use memory efficiently > - and has enhanced diagnostics. SLUB is the default choice for > - a slab allocator. > - > -config SLOB_DEPRECATED > - depends on EXPERT > - bool "SLOB (Simple Allocator - DEPRECATED)" > - depends on !PREEMPT_RT > - help > - Deprecated and scheduled for removal in a few cycles. SLUB > - recommended as replacement. CONFIG_SLUB_TINY can be considered > - on systems with 16MB or less RAM. > - > - If you need SLOB to stay, please contact linux-mm@kvack.org and > - people listed in the SLAB ALLOCATOR section of MAINTAINERS file, > - with your use case. > - > - SLOB replaces the stock allocator with a drastically simpler > - allocator. SLOB is generally more space efficient but > - does not perform as well on large systems. > - > -endchoice > - > -config SLOB > - bool > - default y > - depends on SLOB_DEPRECATED > - > -config SLUB_TINY > - bool "Configure SLUB for minimal memory footprint" > - depends on SLUB && EXPERT > - select SLAB_MERGE_DEFAULT > - help > - Configures the SLUB allocator in a way to achieve minimal memory > - footprint, sacrificing scalability, debugging and other features. > - This is intended only for the smallest system that had used the > - SLOB allocator and is not recommended for systems with more than > - 16MB RAM. > - > - If unsure, say N. > - > -config SLAB_MERGE_DEFAULT > - bool "Allow slab caches to be merged" > - default y > - depends on SLAB || SLUB > - help > - For reduced kernel memory fragmentation, slab caches can be > - merged when they share the same size and other characteristics. > - This carries a risk of kernel heap overflows being able to > - overwrite objects from merged caches (and more easily control > - cache layout), which makes such heap attacks easier to exploit > - by attackers. By keeping caches unmerged, these kinds of exploits > - can usually only damage objects in the same cache. To disable > - merging at runtime, "slab_nomerge" can be passed on the kernel > - command line. > - > -config SLAB_FREELIST_RANDOM > - bool "Randomize slab freelist" > - depends on SLAB || (SLUB && !SLUB_TINY) > - help > - Randomizes the freelist order used on creating new pages. This > - security feature reduces the predictability of the kernel slab > - allocator against heap overflows. > - > -config SLAB_FREELIST_HARDENED > - bool "Harden slab freelist metadata" > - depends on SLAB || (SLUB && !SLUB_TINY) > - help > - Many kernel heap attacks try to target slab cache metadata and > - other infrastructure. This options makes minor performance > - sacrifices to harden the kernel slab allocator against common > - freelist exploit methods. Some slab implementations have more > - sanity-checking than others. This option is most effective with > - CONFIG_SLUB. > - > -config SLUB_STATS > - default n > - bool "Enable SLUB performance statistics" > - depends on SLUB && SYSFS && !SLUB_TINY > - help > - SLUB statistics are useful to debug SLUBs allocation behavior in > - order find ways to optimize the allocator. This should never be > - enabled for production use since keeping statistics slows down > - the allocator by a few percentage points. The slabinfo command > - supports the determination of the most active slabs to figure > - out which slabs are relevant to a particular load. > - Try running: slabinfo -DA > - > -config SLUB_CPU_PARTIAL > - default y > - depends on SLUB && SMP && !SLUB_TINY > - bool "SLUB per cpu partial cache" > - help > - Per cpu partial caches accelerate objects allocation and freeing > - that is local to a processor at the price of more indeterminism > - in the latency of the free. On overflow these caches will be cleared > - which requires the taking of locks that may cause latency spikes. > - Typically one would choose no for a realtime system. > - > -endmenu # SLAB allocator options > - > config SHUFFLE_PAGE_ALLOCATOR > bool "Page allocator randomization" > - default SLAB_FREELIST_RANDOM && ACPI_NUMA > + default ACPI_NUMA > help > Randomization of the page allocator improves the average > utilization of a direct-mapped memory-side-cache. See section > @@ -345,10 +220,9 @@ config SHUFFLE_PAGE_ALLOCATOR > 6.2a specification for an example of how a platform advertises > the presence of a memory-side-cache. There are also incidental > security benefits as it reduces the predictability of page > - allocations to compliment SLAB_FREELIST_RANDOM, but the > - default granularity of shuffling on the "MAX_ORDER - 1" i.e, > - 10th order of pages is selected based on cache utilization > - benefits on x86. > + allocations, but the default granularity of shuffling on the > + "MAX_ORDER - 1" i.e, 10th order of pages is selected based on > + cache utilization benefits on x86. > > While the randomization improves cache utilization it may > negatively impact workloads on platforms without a cache. For > diff --git a/mm/Makefile b/mm/Makefile > index 8e105e5b3e29..18b0bb245fc3 100644 > --- a/mm/Makefile > +++ b/mm/Makefile > @@ -4,16 +4,12 @@ > # > > KASAN_SANITIZE_slab_common.o := n > -KASAN_SANITIZE_slab.o := n > -KASAN_SANITIZE_slub.o := n > KCSAN_SANITIZE_kmemleak.o := n > > # These produce frequent data race reports: most of them are due to races on > # the same word but accesses to different bits of that word. Re-enable KCSAN > # for these when we have more consensus on what to do about them. > KCSAN_SANITIZE_slab_common.o := n > -KCSAN_SANITIZE_slab.o := n > -KCSAN_SANITIZE_slub.o := n > KCSAN_SANITIZE_page_alloc.o := n > # But enable explicit instrumentation for memory barriers. > KCSAN_INSTRUMENT_BARRIERS := y > @@ -22,9 +18,6 @@ KCSAN_INSTRUMENT_BARRIERS := y > # flaky coverage that is not a function of syscall inputs. E.g. slab is out of > # free pages, or a task is migrated between nodes. > KCOV_INSTRUMENT_slab_common.o := n > -KCOV_INSTRUMENT_slob.o := n > -KCOV_INSTRUMENT_slab.o := n > -KCOV_INSTRUMENT_slub.o := n > KCOV_INSTRUMENT_page_alloc.o := n > KCOV_INSTRUMENT_debug-pagealloc.o := n > KCOV_INSTRUMENT_kmemleak.o := n > @@ -81,12 +74,9 @@ obj-$(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP) += hugetlb_vmemmap.o > obj-$(CONFIG_NUMA) += mempolicy.o > obj-$(CONFIG_SPARSEMEM) += sparse.o > obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o > -obj-$(CONFIG_SLOB) += slob.o > obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o > obj-$(CONFIG_KSM) += ksm.o > obj-$(CONFIG_PAGE_POISONING) += page_poison.o > -obj-$(CONFIG_SLAB) += slab.o > -obj-$(CONFIG_SLUB) += slub.o > obj-$(CONFIG_KASAN) += kasan/ > obj-$(CONFIG_KFENCE) += kfence/ > obj-$(CONFIG_KMSAN) += kmsan/ > diff --git a/mm/slab.c b/mm/slab.c > deleted file mode 100644 > index edbe722fb906..000000000000 > --- a/mm/slab.c > +++ /dev/null > @@ -1,4046 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * linux/mm/slab.c > - * Written by Mark Hemment, 1996/97. > - * (markhe@nextd.demon.co.uk) > - * > - * kmem_cache_destroy() + some cleanup - 1999 Andrea Arcangeli > - * > - * Major cleanup, different bufctl logic, per-cpu arrays > - * (c) 2000 Manfred Spraul > - * > - * Cleanup, make the head arrays unconditional, preparation for NUMA > - * (c) 2002 Manfred Spraul > - * > - * An implementation of the Slab Allocator as described in outline in; > - * UNIX Internals: The New Frontiers by Uresh Vahalia > - * Pub: Prentice Hall ISBN 0-13-101908-2 > - * or with a little more detail in; > - * The Slab Allocator: An Object-Caching Kernel Memory Allocator > - * Jeff Bonwick (Sun Microsystems). > - * Presented at: USENIX Summer 1994 Technical Conference > - * > - * The memory is organized in caches, one cache for each object type. > - * (e.g. inode_cache, dentry_cache, buffer_head, vm_area_struct) > - * Each cache consists out of many slabs (they are small (usually one > - * page long) and always contiguous), and each slab contains multiple > - * initialized objects. > - * > - * This means, that your constructor is used only for newly allocated > - * slabs and you must pass objects with the same initializations to > - * kmem_cache_free. > - * > - * Each cache can only support one memory type (GFP_DMA, GFP_HIGHMEM, > - * normal). If you need a special memory type, then must create a new > - * cache for that memory type. > - * > - * In order to reduce fragmentation, the slabs are sorted in 3 groups: > - * full slabs with 0 free objects > - * partial slabs > - * empty slabs with no allocated objects > - * > - * If partial slabs exist, then new allocations come from these slabs, > - * otherwise from empty slabs or new slabs are allocated. > - * > - * kmem_cache_destroy() CAN CRASH if you try to allocate from the cache > - * during kmem_cache_destroy(). The caller must prevent concurrent allocs. > - * > - * Each cache has a short per-cpu head array, most allocs > - * and frees go into that array, and if that array overflows, then 1/2 > - * of the entries in the array are given back into the global cache. > - * The head array is strictly LIFO and should improve the cache hit rates. > - * On SMP, it additionally reduces the spinlock operations. > - * > - * The c_cpuarray may not be read with enabled local interrupts - > - * it's changed with a smp_call_function(). > - * > - * SMP synchronization: > - * constructors and destructors are called without any locking. > - * Several members in struct kmem_cache and struct slab never change, they > - * are accessed without any locking. > - * The per-cpu arrays are never accessed from the wrong cpu, no locking, > - * and local interrupts are disabled so slab code is preempt-safe. > - * The non-constant members are protected with a per-cache irq spinlock. > - * > - * Many thanks to Mark Hemment, who wrote another per-cpu slab patch > - * in 2000 - many ideas in the current implementation are derived from > - * his patch. > - * > - * Further notes from the original documentation: > - * > - * 11 April '97. Started multi-threading - markhe > - * The global cache-chain is protected by the mutex 'slab_mutex'. > - * The sem is only needed when accessing/extending the cache-chain, which > - * can never happen inside an interrupt (kmem_cache_create(), > - * kmem_cache_shrink() and kmem_cache_reap()). > - * > - * At present, each engine can be growing a cache. This should be blocked. > - * > - * 15 March 2005. NUMA slab allocator. > - * Shai Fultheim <shai@scalex86.org>. > - * Shobhit Dayal <shobhit@calsoftinc.com> > - * Alok N Kataria <alokk@calsoftinc.com> > - * Christoph Lameter <christoph@lameter.com> > - * > - * Modified the slab allocator to be node aware on NUMA systems. > - * Each node has its own list of partial, free and full slabs. > - * All object allocations for a node occur from node specific slab lists. > - */ > - > -#include <linux/slab.h> > -#include <linux/mm.h> > -#include <linux/poison.h> > -#include <linux/swap.h> > -#include <linux/cache.h> > -#include <linux/interrupt.h> > -#include <linux/init.h> > -#include <linux/compiler.h> > -#include <linux/cpuset.h> > -#include <linux/proc_fs.h> > -#include <linux/seq_file.h> > -#include <linux/notifier.h> > -#include <linux/kallsyms.h> > -#include <linux/kfence.h> > -#include <linux/cpu.h> > -#include <linux/sysctl.h> > -#include <linux/module.h> > -#include <linux/rcupdate.h> > -#include <linux/string.h> > -#include <linux/uaccess.h> > -#include <linux/nodemask.h> > -#include <linux/kmemleak.h> > -#include <linux/mempolicy.h> > -#include <linux/mutex.h> > -#include <linux/fault-inject.h> > -#include <linux/rtmutex.h> > -#include <linux/reciprocal_div.h> > -#include <linux/debugobjects.h> > -#include <linux/memory.h> > -#include <linux/prefetch.h> > -#include <linux/sched/task_stack.h> > - > -#include <net/sock.h> > - > -#include <asm/cacheflush.h> > -#include <asm/tlbflush.h> > -#include <asm/page.h> > - > -#include <trace/events/kmem.h> > - > -#include "internal.h" > - > -#include "slab.h" > - > -/* > - * DEBUG - 1 for kmem_cache_create() to honour; SLAB_RED_ZONE & SLAB_POISON. > - * 0 for faster, smaller code (especially in the critical paths). > - * > - * STATS - 1 to collect stats for /proc/slabinfo. > - * 0 for faster, smaller code (especially in the critical paths). > - * > - * FORCED_DEBUG - 1 enables SLAB_RED_ZONE and SLAB_POISON (if possible) > - */ > - > -#ifdef CONFIG_DEBUG_SLAB > -#define DEBUG 1 > -#define STATS 1 > -#define FORCED_DEBUG 1 > -#else > -#define DEBUG 0 > -#define STATS 0 > -#define FORCED_DEBUG 0 > -#endif > - > -/* Shouldn't this be in a header file somewhere? */ > -#define BYTES_PER_WORD sizeof(void *) > -#define REDZONE_ALIGN max(BYTES_PER_WORD, __alignof__(unsigned long long)) > - > -#ifndef ARCH_KMALLOC_FLAGS > -#define ARCH_KMALLOC_FLAGS SLAB_HWCACHE_ALIGN > -#endif > - > -#define FREELIST_BYTE_INDEX (((PAGE_SIZE >> BITS_PER_BYTE) \ > - <= SLAB_OBJ_MIN_SIZE) ? 1 : 0) > - > -#if FREELIST_BYTE_INDEX > -typedef unsigned char freelist_idx_t; > -#else > -typedef unsigned short freelist_idx_t; > -#endif > - > -#define SLAB_OBJ_MAX_NUM ((1 << sizeof(freelist_idx_t) * BITS_PER_BYTE) - 1) > - > -/* > - * struct array_cache > - * > - * Purpose: > - * - LIFO ordering, to hand out cache-warm objects from _alloc > - * - reduce the number of linked list operations > - * - reduce spinlock operations > - * > - * The limit is stored in the per-cpu structure to reduce the data cache > - * footprint. > - * > - */ > -struct array_cache { > - unsigned int avail; > - unsigned int limit; > - unsigned int batchcount; > - unsigned int touched; > - void *entry[]; /* > - * Must have this definition in here for the proper > - * alignment of array_cache. Also simplifies accessing > - * the entries. > - */ > -}; > - > -struct alien_cache { > - spinlock_t lock; > - struct array_cache ac; > -}; > - > -/* > - * Need this for bootstrapping a per node allocator. > - */ > -#define NUM_INIT_LISTS (2 * MAX_NUMNODES) > -static struct kmem_cache_node __initdata init_kmem_cache_node[NUM_INIT_LISTS]; > -#define CACHE_CACHE 0 > -#define SIZE_NODE (MAX_NUMNODES) > - > -static int drain_freelist(struct kmem_cache *cache, > - struct kmem_cache_node *n, int tofree); > -static void free_block(struct kmem_cache *cachep, void **objpp, int len, > - int node, struct list_head *list); > -static void slabs_destroy(struct kmem_cache *cachep, struct list_head *list); > -static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp); > -static void cache_reap(struct work_struct *unused); > - > -static inline void fixup_objfreelist_debug(struct kmem_cache *cachep, > - void **list); > -static inline void fixup_slab_list(struct kmem_cache *cachep, > - struct kmem_cache_node *n, struct slab *slab, > - void **list); > - > -#define INDEX_NODE kmalloc_index(sizeof(struct kmem_cache_node)) > - > -static void kmem_cache_node_init(struct kmem_cache_node *parent) > -{ > - INIT_LIST_HEAD(&parent->slabs_full); > - INIT_LIST_HEAD(&parent->slabs_partial); > - INIT_LIST_HEAD(&parent->slabs_free); > - parent->total_slabs = 0; > - parent->free_slabs = 0; > - parent->shared = NULL; > - parent->alien = NULL; > - parent->colour_next = 0; > - raw_spin_lock_init(&parent->list_lock); > - parent->free_objects = 0; > - parent->free_touched = 0; > -} > - > -#define MAKE_LIST(cachep, listp, slab, nodeid) \ > - do { \ > - INIT_LIST_HEAD(listp); \ > - list_splice(&get_node(cachep, nodeid)->slab, listp); \ > - } while (0) > - > -#define MAKE_ALL_LISTS(cachep, ptr, nodeid) \ > - do { \ > - MAKE_LIST((cachep), (&(ptr)->slabs_full), slabs_full, nodeid); \ > - MAKE_LIST((cachep), (&(ptr)->slabs_partial), slabs_partial, nodeid); \ > - MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid); \ > - } while (0) > - > -#define CFLGS_OBJFREELIST_SLAB ((slab_flags_t __force)0x40000000U) > -#define CFLGS_OFF_SLAB ((slab_flags_t __force)0x80000000U) > -#define OBJFREELIST_SLAB(x) ((x)->flags & CFLGS_OBJFREELIST_SLAB) > -#define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB) > - > -#define BATCHREFILL_LIMIT 16 > -/* > - * Optimization question: fewer reaps means less probability for unnecessary > - * cpucache drain/refill cycles. > - * > - * OTOH the cpuarrays can contain lots of objects, > - * which could lock up otherwise freeable slabs. > - */ > -#define REAPTIMEOUT_AC (2*HZ) > -#define REAPTIMEOUT_NODE (4*HZ) > - > -#if STATS > -#define STATS_INC_ACTIVE(x) ((x)->num_active++) > -#define STATS_DEC_ACTIVE(x) ((x)->num_active--) > -#define STATS_INC_ALLOCED(x) ((x)->num_allocations++) > -#define STATS_INC_GROWN(x) ((x)->grown++) > -#define STATS_ADD_REAPED(x, y) ((x)->reaped += (y)) > -#define STATS_SET_HIGH(x) \ > - do { \ > - if ((x)->num_active > (x)->high_mark) \ > - (x)->high_mark = (x)->num_active; \ > - } while (0) > -#define STATS_INC_ERR(x) ((x)->errors++) > -#define STATS_INC_NODEALLOCS(x) ((x)->node_allocs++) > -#define STATS_INC_NODEFREES(x) ((x)->node_frees++) > -#define STATS_INC_ACOVERFLOW(x) ((x)->node_overflow++) > -#define STATS_SET_FREEABLE(x, i) \ > - do { \ > - if ((x)->max_freeable < i) \ > - (x)->max_freeable = i; \ > - } while (0) > -#define STATS_INC_ALLOCHIT(x) atomic_inc(&(x)->allochit) > -#define STATS_INC_ALLOCMISS(x) atomic_inc(&(x)->allocmiss) > -#define STATS_INC_FREEHIT(x) atomic_inc(&(x)->freehit) > -#define STATS_INC_FREEMISS(x) atomic_inc(&(x)->freemiss) > -#else > -#define STATS_INC_ACTIVE(x) do { } while (0) > -#define STATS_DEC_ACTIVE(x) do { } while (0) > -#define STATS_INC_ALLOCED(x) do { } while (0) > -#define STATS_INC_GROWN(x) do { } while (0) > -#define STATS_ADD_REAPED(x, y) do { (void)(y); } while (0) > -#define STATS_SET_HIGH(x) do { } while (0) > -#define STATS_INC_ERR(x) do { } while (0) > -#define STATS_INC_NODEALLOCS(x) do { } while (0) > -#define STATS_INC_NODEFREES(x) do { } while (0) > -#define STATS_INC_ACOVERFLOW(x) do { } while (0) > -#define STATS_SET_FREEABLE(x, i) do { } while (0) > -#define STATS_INC_ALLOCHIT(x) do { } while (0) > -#define STATS_INC_ALLOCMISS(x) do { } while (0) > -#define STATS_INC_FREEHIT(x) do { } while (0) > -#define STATS_INC_FREEMISS(x) do { } while (0) > -#endif > - > -#if DEBUG > - > -/* > - * memory layout of objects: > - * 0 : objp > - * 0 .. cachep->obj_offset - BYTES_PER_WORD - 1: padding. This ensures that > - * the end of an object is aligned with the end of the real > - * allocation. Catches writes behind the end of the allocation. > - * cachep->obj_offset - BYTES_PER_WORD .. cachep->obj_offset - 1: > - * redzone word. > - * cachep->obj_offset: The real object. > - * cachep->size - 2* BYTES_PER_WORD: redzone word [BYTES_PER_WORD long] > - * cachep->size - 1* BYTES_PER_WORD: last caller address > - * [BYTES_PER_WORD long] > - */ > -static int obj_offset(struct kmem_cache *cachep) > -{ > - return cachep->obj_offset; > -} > - > -static unsigned long long *dbg_redzone1(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); > - return (unsigned long long *) (objp + obj_offset(cachep) - > - sizeof(unsigned long long)); > -} > - > -static unsigned long long *dbg_redzone2(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); > - if (cachep->flags & SLAB_STORE_USER) > - return (unsigned long long *)(objp + cachep->size - > - sizeof(unsigned long long) - > - REDZONE_ALIGN); > - return (unsigned long long *) (objp + cachep->size - > - sizeof(unsigned long long)); > -} > - > -static void **dbg_userword(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_STORE_USER)); > - return (void **)(objp + cachep->size - BYTES_PER_WORD); > -} > - > -#else > - > -#define obj_offset(x) 0 > -#define dbg_redzone1(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) > -#define dbg_redzone2(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) > -#define dbg_userword(cachep, objp) ({BUG(); (void **)NULL;}) > - > -#endif > - > -/* > - * Do not go above this order unless 0 objects fit into the slab or > - * overridden on the command line. > - */ > -#define SLAB_MAX_ORDER_HI 1 > -#define SLAB_MAX_ORDER_LO 0 > -static int slab_max_order = SLAB_MAX_ORDER_LO; > -static bool slab_max_order_set __initdata; > - > -static inline void *index_to_obj(struct kmem_cache *cache, > - const struct slab *slab, unsigned int idx) > -{ > - return slab->s_mem + cache->size * idx; > -} > - > -#define BOOT_CPUCACHE_ENTRIES 1 > -/* internal cache of cache description objs */ > -static struct kmem_cache kmem_cache_boot = { > - .batchcount = 1, > - .limit = BOOT_CPUCACHE_ENTRIES, > - .shared = 1, > - .size = sizeof(struct kmem_cache), > - .name = "kmem_cache", > -}; > - > -static DEFINE_PER_CPU(struct delayed_work, slab_reap_work); > - > -static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) > -{ > - return this_cpu_ptr(cachep->cpu_cache); > -} > - > -/* > - * Calculate the number of objects and left-over bytes for a given buffer size. > - */ > -static unsigned int cache_estimate(unsigned long gfporder, size_t buffer_size, > - slab_flags_t flags, size_t *left_over) > -{ > - unsigned int num; > - size_t slab_size = PAGE_SIZE << gfporder; > - > - /* > - * The slab management structure can be either off the slab or > - * on it. For the latter case, the memory allocated for a > - * slab is used for: > - * > - * - @buffer_size bytes for each object > - * - One freelist_idx_t for each object > - * > - * We don't need to consider alignment of freelist because > - * freelist will be at the end of slab page. The objects will be > - * at the correct alignment. > - * > - * If the slab management structure is off the slab, then the > - * alignment will already be calculated into the size. Because > - * the slabs are all pages aligned, the objects will be at the > - * correct alignment when allocated. > - */ > - if (flags & (CFLGS_OBJFREELIST_SLAB | CFLGS_OFF_SLAB)) { > - num = slab_size / buffer_size; > - *left_over = slab_size % buffer_size; > - } else { > - num = slab_size / (buffer_size + sizeof(freelist_idx_t)); > - *left_over = slab_size % > - (buffer_size + sizeof(freelist_idx_t)); > - } > - > - return num; > -} > - > -#if DEBUG > -#define slab_error(cachep, msg) __slab_error(__func__, cachep, msg) > - > -static void __slab_error(const char *function, struct kmem_cache *cachep, > - char *msg) > -{ > - pr_err("slab error in %s(): cache `%s': %s\n", > - function, cachep->name, msg); > - dump_stack(); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > -#endif > - > -/* > - * By default on NUMA we use alien caches to stage the freeing of > - * objects allocated from other nodes. This causes massive memory > - * inefficiencies when using fake NUMA setup to split memory into a > - * large number of small nodes, so it can be disabled on the command > - * line > - */ > - > -static int use_alien_caches __read_mostly = 1; > -static int __init noaliencache_setup(char *s) > -{ > - use_alien_caches = 0; > - return 1; > -} > -__setup("noaliencache", noaliencache_setup); > - > -static int __init slab_max_order_setup(char *str) > -{ > - get_option(&str, &slab_max_order); > - slab_max_order = slab_max_order < 0 ? 0 : > - min(slab_max_order, MAX_ORDER - 1); > - slab_max_order_set = true; > - > - return 1; > -} > -__setup("slab_max_order=", slab_max_order_setup); > - > -#ifdef CONFIG_NUMA > -/* > - * Special reaping functions for NUMA systems called from cache_reap(). > - * These take care of doing round robin flushing of alien caches (containing > - * objects freed on different nodes from which they were allocated) and the > - * flushing of remote pcps by calling drain_node_pages. > - */ > -static DEFINE_PER_CPU(unsigned long, slab_reap_node); > - > -static void init_reap_node(int cpu) > -{ > - per_cpu(slab_reap_node, cpu) = next_node_in(cpu_to_mem(cpu), > - node_online_map); > -} > - > -static void next_reap_node(void) > -{ > - int node = __this_cpu_read(slab_reap_node); > - > - node = next_node_in(node, node_online_map); > - __this_cpu_write(slab_reap_node, node); > -} > - > -#else > -#define init_reap_node(cpu) do { } while (0) > -#define next_reap_node(void) do { } while (0) > -#endif > - > -/* > - * Initiate the reap timer running on the target CPU. We run at around 1 to 2Hz > - * via the workqueue/eventd. > - * Add the CPU number into the expiration time to minimize the possibility of > - * the CPUs getting into lockstep and contending for the global cache chain > - * lock. > - */ > -static void start_cpu_timer(int cpu) > -{ > - struct delayed_work *reap_work = &per_cpu(slab_reap_work, cpu); > - > - if (reap_work->work.func == NULL) { > - init_reap_node(cpu); > - INIT_DEFERRABLE_WORK(reap_work, cache_reap); > - schedule_delayed_work_on(cpu, reap_work, > - __round_jiffies_relative(HZ, cpu)); > - } > -} > - > -static void init_arraycache(struct array_cache *ac, int limit, int batch) > -{ > - if (ac) { > - ac->avail = 0; > - ac->limit = limit; > - ac->batchcount = batch; > - ac->touched = 0; > - } > -} > - > -static struct array_cache *alloc_arraycache(int node, int entries, > - int batchcount, gfp_t gfp) > -{ > - size_t memsize = sizeof(void *) * entries + sizeof(struct array_cache); > - struct array_cache *ac = NULL; > - > - ac = kmalloc_node(memsize, gfp, node); > - /* > - * The array_cache structures contain pointers to free object. > - * However, when such objects are allocated or transferred to another > - * cache the pointers are not cleared and they could be counted as > - * valid references during a kmemleak scan. Therefore, kmemleak must > - * not scan such objects. > - */ > - kmemleak_no_scan(ac); > - init_arraycache(ac, entries, batchcount); > - return ac; > -} > - > -static noinline void cache_free_pfmemalloc(struct kmem_cache *cachep, > - struct slab *slab, void *objp) > -{ > - struct kmem_cache_node *n; > - int slab_node; > - LIST_HEAD(list); > - > - slab_node = slab_nid(slab); > - n = get_node(cachep, slab_node); > - > - raw_spin_lock(&n->list_lock); > - free_block(cachep, &objp, 1, slab_node, &list); > - raw_spin_unlock(&n->list_lock); > - > - slabs_destroy(cachep, &list); > -} > - > -/* > - * Transfer objects in one arraycache to another. > - * Locking must be handled by the caller. > - * > - * Return the number of entries transferred. > - */ > -static int transfer_objects(struct array_cache *to, > - struct array_cache *from, unsigned int max) > -{ > - /* Figure out how many entries to transfer */ > - int nr = min3(from->avail, max, to->limit - to->avail); > - > - if (!nr) > - return 0; > - > - memcpy(to->entry + to->avail, from->entry + from->avail - nr, > - sizeof(void *) *nr); > - > - from->avail -= nr; > - to->avail += nr; > - return nr; > -} > - > -/* &alien->lock must be held by alien callers. */ > -static __always_inline void __free_one(struct array_cache *ac, void *objp) > -{ > - /* Avoid trivial double-free. */ > - if (IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && > - WARN_ON_ONCE(ac->avail > 0 && ac->entry[ac->avail - 1] == objp)) > - return; > - ac->entry[ac->avail++] = objp; > -} > - > -#ifndef CONFIG_NUMA > - > -#define drain_alien_cache(cachep, alien) do { } while (0) > -#define reap_alien(cachep, n) do { } while (0) > - > -static inline struct alien_cache **alloc_alien_cache(int node, > - int limit, gfp_t gfp) > -{ > - return NULL; > -} > - > -static inline void free_alien_cache(struct alien_cache **ac_ptr) > -{ > -} > - > -static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) > -{ > - return 0; > -} > - > -static inline gfp_t gfp_exact_node(gfp_t flags) > -{ > - return flags & ~__GFP_NOFAIL; > -} > - > -#else /* CONFIG_NUMA */ > - > -static struct alien_cache *__alloc_alien_cache(int node, int entries, > - int batch, gfp_t gfp) > -{ > - size_t memsize = sizeof(void *) * entries + sizeof(struct alien_cache); > - struct alien_cache *alc = NULL; > - > - alc = kmalloc_node(memsize, gfp, node); > - if (alc) { > - kmemleak_no_scan(alc); > - init_arraycache(&alc->ac, entries, batch); > - spin_lock_init(&alc->lock); > - } > - return alc; > -} > - > -static struct alien_cache **alloc_alien_cache(int node, int limit, gfp_t gfp) > -{ > - struct alien_cache **alc_ptr; > - int i; > - > - if (limit > 1) > - limit = 12; > - alc_ptr = kcalloc_node(nr_node_ids, sizeof(void *), gfp, node); > - if (!alc_ptr) > - return NULL; > - > - for_each_node(i) { > - if (i == node || !node_online(i)) > - continue; > - alc_ptr[i] = __alloc_alien_cache(node, limit, 0xbaadf00d, gfp); > - if (!alc_ptr[i]) { > - for (i--; i >= 0; i--) > - kfree(alc_ptr[i]); > - kfree(alc_ptr); > - return NULL; > - } > - } > - return alc_ptr; > -} > - > -static void free_alien_cache(struct alien_cache **alc_ptr) > -{ > - int i; > - > - if (!alc_ptr) > - return; > - for_each_node(i) > - kfree(alc_ptr[i]); > - kfree(alc_ptr); > -} > - > -static void __drain_alien_cache(struct kmem_cache *cachep, > - struct array_cache *ac, int node, > - struct list_head *list) > -{ > - struct kmem_cache_node *n = get_node(cachep, node); > - > - if (ac->avail) { > - raw_spin_lock(&n->list_lock); > - /* > - * Stuff objects into the remote nodes shared array first. > - * That way we could avoid the overhead of putting the objects > - * into the free lists and getting them back later. > - */ > - if (n->shared) > - transfer_objects(n->shared, ac, ac->limit); > - > - free_block(cachep, ac->entry, ac->avail, node, list); > - ac->avail = 0; > - raw_spin_unlock(&n->list_lock); > - } > -} > - > -/* > - * Called from cache_reap() to regularly drain alien caches round robin. > - */ > -static void reap_alien(struct kmem_cache *cachep, struct kmem_cache_node *n) > -{ > - int node = __this_cpu_read(slab_reap_node); > - > - if (n->alien) { > - struct alien_cache *alc = n->alien[node]; > - struct array_cache *ac; > - > - if (alc) { > - ac = &alc->ac; > - if (ac->avail && spin_trylock_irq(&alc->lock)) { > - LIST_HEAD(list); > - > - __drain_alien_cache(cachep, ac, node, &list); > - spin_unlock_irq(&alc->lock); > - slabs_destroy(cachep, &list); > - } > - } > - } > -} > - > -static void drain_alien_cache(struct kmem_cache *cachep, > - struct alien_cache **alien) > -{ > - int i = 0; > - struct alien_cache *alc; > - struct array_cache *ac; > - unsigned long flags; > - > - for_each_online_node(i) { > - alc = alien[i]; > - if (alc) { > - LIST_HEAD(list); > - > - ac = &alc->ac; > - spin_lock_irqsave(&alc->lock, flags); > - __drain_alien_cache(cachep, ac, i, &list); > - spin_unlock_irqrestore(&alc->lock, flags); > - slabs_destroy(cachep, &list); > - } > - } > -} > - > -static int __cache_free_alien(struct kmem_cache *cachep, void *objp, > - int node, int slab_node) > -{ > - struct kmem_cache_node *n; > - struct alien_cache *alien = NULL; > - struct array_cache *ac; > - LIST_HEAD(list); > - > - n = get_node(cachep, node); > - STATS_INC_NODEFREES(cachep); > - if (n->alien && n->alien[slab_node]) { > - alien = n->alien[slab_node]; > - ac = &alien->ac; > - spin_lock(&alien->lock); > - if (unlikely(ac->avail == ac->limit)) { > - STATS_INC_ACOVERFLOW(cachep); > - __drain_alien_cache(cachep, ac, slab_node, &list); > - } > - __free_one(ac, objp); > - spin_unlock(&alien->lock); > - slabs_destroy(cachep, &list); > - } else { > - n = get_node(cachep, slab_node); > - raw_spin_lock(&n->list_lock); > - free_block(cachep, &objp, 1, slab_node, &list); > - raw_spin_unlock(&n->list_lock); > - slabs_destroy(cachep, &list); > - } > - return 1; > -} > - > -static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) > -{ > - int slab_node = slab_nid(virt_to_slab(objp)); > - int node = numa_mem_id(); > - /* > - * Make sure we are not freeing an object from another node to the array > - * cache on this cpu. > - */ > - if (likely(node == slab_node)) > - return 0; > - > - return __cache_free_alien(cachep, objp, node, slab_node); > -} > - > -/* > - * Construct gfp mask to allocate from a specific node but do not reclaim or > - * warn about failures. > - */ > -static inline gfp_t gfp_exact_node(gfp_t flags) > -{ > - return (flags | __GFP_THISNODE | __GFP_NOWARN) & ~(__GFP_RECLAIM|__GFP_NOFAIL); > -} > -#endif > - > -static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp) > -{ > - struct kmem_cache_node *n; > - > - /* > - * Set up the kmem_cache_node for cpu before we can > - * begin anything. Make sure some other cpu on this > - * node has not already allocated this > - */ > - n = get_node(cachep, node); > - if (n) { > - raw_spin_lock_irq(&n->list_lock); > - n->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount + > - cachep->num; > - raw_spin_unlock_irq(&n->list_lock); > - > - return 0; > - } > - > - n = kmalloc_node(sizeof(struct kmem_cache_node), gfp, node); > - if (!n) > - return -ENOMEM; > - > - kmem_cache_node_init(n); > - n->next_reap = jiffies + REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - > - n->free_limit = > - (1 + nr_cpus_node(node)) * cachep->batchcount + cachep->num; > - > - /* > - * The kmem_cache_nodes don't come and go as CPUs > - * come and go. slab_mutex provides sufficient > - * protection here. > - */ > - cachep->node[node] = n; > - > - return 0; > -} > - > -#if defined(CONFIG_NUMA) || defined(CONFIG_SMP) > -/* > - * Allocates and initializes node for a node on each slab cache, used for > - * either memory or cpu hotplug. If memory is being hot-added, the kmem_cache_node > - * will be allocated off-node since memory is not yet online for the new node. > - * When hotplugging memory or a cpu, existing nodes are not replaced if > - * already in use. > - * > - * Must hold slab_mutex. > - */ > -static int init_cache_node_node(int node) > -{ > - int ret; > - struct kmem_cache *cachep; > - > - list_for_each_entry(cachep, &slab_caches, list) { > - ret = init_cache_node(cachep, node, GFP_KERNEL); > - if (ret) > - return ret; > - } > - > - return 0; > -} > -#endif > - > -static int setup_kmem_cache_node(struct kmem_cache *cachep, > - int node, gfp_t gfp, bool force_change) > -{ > - int ret = -ENOMEM; > - struct kmem_cache_node *n; > - struct array_cache *old_shared = NULL; > - struct array_cache *new_shared = NULL; > - struct alien_cache **new_alien = NULL; > - LIST_HEAD(list); > - > - if (use_alien_caches) { > - new_alien = alloc_alien_cache(node, cachep->limit, gfp); > - if (!new_alien) > - goto fail; > - } > - > - if (cachep->shared) { > - new_shared = alloc_arraycache(node, > - cachep->shared * cachep->batchcount, 0xbaadf00d, gfp); > - if (!new_shared) > - goto fail; > - } > - > - ret = init_cache_node(cachep, node, gfp); > - if (ret) > - goto fail; > - > - n = get_node(cachep, node); > - raw_spin_lock_irq(&n->list_lock); > - if (n->shared && force_change) { > - free_block(cachep, n->shared->entry, > - n->shared->avail, node, &list); > - n->shared->avail = 0; > - } > - > - if (!n->shared || force_change) { > - old_shared = n->shared; > - n->shared = new_shared; > - new_shared = NULL; > - } > - > - if (!n->alien) { > - n->alien = new_alien; > - new_alien = NULL; > - } > - > - raw_spin_unlock_irq(&n->list_lock); > - slabs_destroy(cachep, &list); > - > - /* > - * To protect lockless access to n->shared during irq disabled context. > - * If n->shared isn't NULL in irq disabled context, accessing to it is > - * guaranteed to be valid until irq is re-enabled, because it will be > - * freed after synchronize_rcu(). > - */ > - if (old_shared && force_change) > - synchronize_rcu(); > - > -fail: > - kfree(old_shared); > - kfree(new_shared); > - free_alien_cache(new_alien); > - > - return ret; > -} > - > -#ifdef CONFIG_SMP > - > -static void cpuup_canceled(long cpu) > -{ > - struct kmem_cache *cachep; > - struct kmem_cache_node *n = NULL; > - int node = cpu_to_mem(cpu); > - const struct cpumask *mask = cpumask_of_node(node); > - > - list_for_each_entry(cachep, &slab_caches, list) { > - struct array_cache *nc; > - struct array_cache *shared; > - struct alien_cache **alien; > - LIST_HEAD(list); > - > - n = get_node(cachep, node); > - if (!n) > - continue; > - > - raw_spin_lock_irq(&n->list_lock); > - > - /* Free limit for this kmem_cache_node */ > - n->free_limit -= cachep->batchcount; > - > - /* cpu is dead; no one can alloc from it. */ > - nc = per_cpu_ptr(cachep->cpu_cache, cpu); > - free_block(cachep, nc->entry, nc->avail, node, &list); > - nc->avail = 0; > - > - if (!cpumask_empty(mask)) { > - raw_spin_unlock_irq(&n->list_lock); > - goto free_slab; > - } > - > - shared = n->shared; > - if (shared) { > - free_block(cachep, shared->entry, > - shared->avail, node, &list); > - n->shared = NULL; > - } > - > - alien = n->alien; > - n->alien = NULL; > - > - raw_spin_unlock_irq(&n->list_lock); > - > - kfree(shared); > - if (alien) { > - drain_alien_cache(cachep, alien); > - free_alien_cache(alien); > - } > - > -free_slab: > - slabs_destroy(cachep, &list); > - } > - /* > - * In the previous loop, all the objects were freed to > - * the respective cache's slabs, now we can go ahead and > - * shrink each nodelist to its limit. > - */ > - list_for_each_entry(cachep, &slab_caches, list) { > - n = get_node(cachep, node); > - if (!n) > - continue; > - drain_freelist(cachep, n, INT_MAX); > - } > -} > - > -static int cpuup_prepare(long cpu) > -{ > - struct kmem_cache *cachep; > - int node = cpu_to_mem(cpu); > - int err; > - > - /* > - * We need to do this right in the beginning since > - * alloc_arraycache's are going to use this list. > - * kmalloc_node allows us to add the slab to the right > - * kmem_cache_node and not this cpu's kmem_cache_node > - */ > - err = init_cache_node_node(node); > - if (err < 0) > - goto bad; > - > - /* > - * Now we can go ahead with allocating the shared arrays and > - * array caches > - */ > - list_for_each_entry(cachep, &slab_caches, list) { > - err = setup_kmem_cache_node(cachep, node, GFP_KERNEL, false); > - if (err) > - goto bad; > - } > - > - return 0; > -bad: > - cpuup_canceled(cpu); > - return -ENOMEM; > -} > - > -int slab_prepare_cpu(unsigned int cpu) > -{ > - int err; > - > - mutex_lock(&slab_mutex); > - err = cpuup_prepare(cpu); > - mutex_unlock(&slab_mutex); > - return err; > -} > - > -/* > - * This is called for a failed online attempt and for a successful > - * offline. > - * > - * Even if all the cpus of a node are down, we don't free the > - * kmem_cache_node of any cache. This is to avoid a race between cpu_down, and > - * a kmalloc allocation from another cpu for memory from the node of > - * the cpu going down. The kmem_cache_node structure is usually allocated from > - * kmem_cache_create() and gets destroyed at kmem_cache_destroy(). > - */ > -int slab_dead_cpu(unsigned int cpu) > -{ > - mutex_lock(&slab_mutex); > - cpuup_canceled(cpu); > - mutex_unlock(&slab_mutex); > - return 0; > -} > -#endif > - > -static int slab_online_cpu(unsigned int cpu) > -{ > - start_cpu_timer(cpu); > - return 0; > -} > - > -static int slab_offline_cpu(unsigned int cpu) > -{ > - /* > - * Shutdown cache reaper. Note that the slab_mutex is held so > - * that if cache_reap() is invoked it cannot do anything > - * expensive but will only modify reap_work and reschedule the > - * timer. > - */ > - cancel_delayed_work_sync(&per_cpu(slab_reap_work, cpu)); > - /* Now the cache_reaper is guaranteed to be not running. */ > - per_cpu(slab_reap_work, cpu).work.func = NULL; > - return 0; > -} > - > -#if defined(CONFIG_NUMA) > -/* > - * Drains freelist for a node on each slab cache, used for memory hot-remove. > - * Returns -EBUSY if all objects cannot be drained so that the node is not > - * removed. > - * > - * Must hold slab_mutex. > - */ > -static int __meminit drain_cache_node_node(int node) > -{ > - struct kmem_cache *cachep; > - int ret = 0; > - > - list_for_each_entry(cachep, &slab_caches, list) { > - struct kmem_cache_node *n; > - > - n = get_node(cachep, node); > - if (!n) > - continue; > - > - drain_freelist(cachep, n, INT_MAX); > - > - if (!list_empty(&n->slabs_full) || > - !list_empty(&n->slabs_partial)) { > - ret = -EBUSY; > - break; > - } > - } > - return ret; > -} > - > -static int __meminit slab_memory_callback(struct notifier_block *self, > - unsigned long action, void *arg) > -{ > - struct memory_notify *mnb = arg; > - int ret = 0; > - int nid; > - > - nid = mnb->status_change_nid; > - if (nid < 0) > - goto out; > - > - switch (action) { > - case MEM_GOING_ONLINE: > - mutex_lock(&slab_mutex); > - ret = init_cache_node_node(nid); > - mutex_unlock(&slab_mutex); > - break; > - case MEM_GOING_OFFLINE: > - mutex_lock(&slab_mutex); > - ret = drain_cache_node_node(nid); > - mutex_unlock(&slab_mutex); > - break; > - case MEM_ONLINE: > - case MEM_OFFLINE: > - case MEM_CANCEL_ONLINE: > - case MEM_CANCEL_OFFLINE: > - break; > - } > -out: > - return notifier_from_errno(ret); > -} > -#endif /* CONFIG_NUMA */ > - > -/* > - * swap the static kmem_cache_node with kmalloced memory > - */ > -static void __init init_list(struct kmem_cache *cachep, struct kmem_cache_node *list, > - int nodeid) > -{ > - struct kmem_cache_node *ptr; > - > - ptr = kmalloc_node(sizeof(struct kmem_cache_node), GFP_NOWAIT, nodeid); > - BUG_ON(!ptr); > - > - memcpy(ptr, list, sizeof(struct kmem_cache_node)); > - /* > - * Do not assume that spinlocks can be initialized via memcpy: > - */ > - raw_spin_lock_init(&ptr->list_lock); > - > - MAKE_ALL_LISTS(cachep, ptr, nodeid); > - cachep->node[nodeid] = ptr; > -} > - > -/* > - * For setting up all the kmem_cache_node for cache whose buffer_size is same as > - * size of kmem_cache_node. > - */ > -static void __init set_up_node(struct kmem_cache *cachep, int index) > -{ > - int node; > - > - for_each_online_node(node) { > - cachep->node[node] = &init_kmem_cache_node[index + node]; > - cachep->node[node]->next_reap = jiffies + > - REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - } > -} > - > -/* > - * Initialisation. Called after the page allocator have been initialised and > - * before smp_init(). > - */ > -void __init kmem_cache_init(void) > -{ > - int i; > - > - kmem_cache = &kmem_cache_boot; > - > - if (!IS_ENABLED(CONFIG_NUMA) || num_possible_nodes() == 1) > - use_alien_caches = 0; > - > - for (i = 0; i < NUM_INIT_LISTS; i++) > - kmem_cache_node_init(&init_kmem_cache_node[i]); > - > - /* > - * Fragmentation resistance on low memory - only use bigger > - * page orders on machines with more than 32MB of memory if > - * not overridden on the command line. > - */ > - if (!slab_max_order_set && totalram_pages() > (32 << 20) >> PAGE_SHIFT) > - slab_max_order = SLAB_MAX_ORDER_HI; > - > - /* Bootstrap is tricky, because several objects are allocated > - * from caches that do not exist yet: > - * 1) initialize the kmem_cache cache: it contains the struct > - * kmem_cache structures of all caches, except kmem_cache itself: > - * kmem_cache is statically allocated. > - * Initially an __init data area is used for the head array and the > - * kmem_cache_node structures, it's replaced with a kmalloc allocated > - * array at the end of the bootstrap. > - * 2) Create the first kmalloc cache. > - * The struct kmem_cache for the new cache is allocated normally. > - * An __init data area is used for the head array. > - * 3) Create the remaining kmalloc caches, with minimally sized > - * head arrays. > - * 4) Replace the __init data head arrays for kmem_cache and the first > - * kmalloc cache with kmalloc allocated arrays. > - * 5) Replace the __init data for kmem_cache_node for kmem_cache and > - * the other cache's with kmalloc allocated memory. > - * 6) Resize the head arrays of the kmalloc caches to their final sizes. > - */ > - > - /* 1) create the kmem_cache */ > - > - /* > - * struct kmem_cache size depends on nr_node_ids & nr_cpu_ids > - */ > - create_boot_cache(kmem_cache, "kmem_cache", > - offsetof(struct kmem_cache, node) + > - nr_node_ids * sizeof(struct kmem_cache_node *), > - SLAB_HWCACHE_ALIGN, 0, 0); > - list_add(&kmem_cache->list, &slab_caches); > - slab_state = PARTIAL; > - > - /* > - * Initialize the caches that provide memory for the kmem_cache_node > - * structures first. Without this, further allocations will bug. > - */ > - kmalloc_caches[KMALLOC_NORMAL][INDEX_NODE] = create_kmalloc_cache( > - kmalloc_info[INDEX_NODE].name[KMALLOC_NORMAL], > - kmalloc_info[INDEX_NODE].size, > - ARCH_KMALLOC_FLAGS, 0, > - kmalloc_info[INDEX_NODE].size); > - slab_state = PARTIAL_NODE; > - setup_kmalloc_cache_index_table(); > - > - /* 5) Replace the bootstrap kmem_cache_node */ > - { > - int nid; > - > - for_each_online_node(nid) { > - init_list(kmem_cache, &init_kmem_cache_node[CACHE_CACHE + nid], nid); > - > - init_list(kmalloc_caches[KMALLOC_NORMAL][INDEX_NODE], > - &init_kmem_cache_node[SIZE_NODE + nid], nid); > - } > - } > - > - create_kmalloc_caches(ARCH_KMALLOC_FLAGS); > -} > - > -void __init kmem_cache_init_late(void) > -{ > - struct kmem_cache *cachep; > - > - /* 6) resize the head arrays to their final sizes */ > - mutex_lock(&slab_mutex); > - list_for_each_entry(cachep, &slab_caches, list) > - if (enable_cpucache(cachep, GFP_NOWAIT)) > - BUG(); > - mutex_unlock(&slab_mutex); > - > - /* Done! */ > - slab_state = FULL; > - > -#ifdef CONFIG_NUMA > - /* > - * Register a memory hotplug callback that initializes and frees > - * node. > - */ > - hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI); > -#endif > - > - /* > - * The reap timers are started later, with a module init call: That part > - * of the kernel is not yet operational. > - */ > -} > - > -static int __init cpucache_init(void) > -{ > - int ret; > - > - /* > - * Register the timers that return unneeded pages to the page allocator > - */ > - ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "SLAB online", > - slab_online_cpu, slab_offline_cpu); > - WARN_ON(ret < 0); > - > - return 0; > -} > -__initcall(cpucache_init); > - > -static noinline void > -slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid) > -{ > -#if DEBUG > - struct kmem_cache_node *n; > - unsigned long flags; > - int node; > - static DEFINE_RATELIMIT_STATE(slab_oom_rs, DEFAULT_RATELIMIT_INTERVAL, > - DEFAULT_RATELIMIT_BURST); > - > - if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slab_oom_rs)) > - return; > - > - pr_warn("SLAB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", > - nodeid, gfpflags, &gfpflags); > - pr_warn(" cache: %s, object size: %d, order: %d\n", > - cachep->name, cachep->size, cachep->gfporder); > - > - for_each_kmem_cache_node(cachep, node, n) { > - unsigned long total_slabs, free_slabs, free_objs; > - > - raw_spin_lock_irqsave(&n->list_lock, flags); > - total_slabs = n->total_slabs; > - free_slabs = n->free_slabs; > - free_objs = n->free_objects; > - raw_spin_unlock_irqrestore(&n->list_lock, flags); > - > - pr_warn(" node %d: slabs: %ld/%ld, objs: %ld/%ld\n", > - node, total_slabs - free_slabs, total_slabs, > - (total_slabs * cachep->num) - free_objs, > - total_slabs * cachep->num); > - } > -#endif > -} > - > -/* > - * Interface to system's page allocator. No need to hold the > - * kmem_cache_node ->list_lock. > - * > - * If we requested dmaable memory, we will get it. Even if we > - * did not request dmaable memory, we might get it, but that > - * would be relatively rare and ignorable. > - */ > -static struct slab *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, > - int nodeid) > -{ > - struct folio *folio; > - struct slab *slab; > - > - flags |= cachep->allocflags; > - > - folio = (struct folio *) __alloc_pages_node(nodeid, flags, cachep->gfporder); > - if (!folio) { > - slab_out_of_memory(cachep, flags, nodeid); > - return NULL; > - } > - > - slab = folio_slab(folio); > - > - account_slab(slab, cachep->gfporder, cachep, flags); > - __folio_set_slab(folio); > - /* Make the flag visible before any changes to folio->mapping */ > - smp_wmb(); > - /* Record if ALLOC_NO_WATERMARKS was set when allocating the slab */ > - if (sk_memalloc_socks() && folio_is_pfmemalloc(folio)) > - slab_set_pfmemalloc(slab); > - > - return slab; > -} > - > -/* > - * Interface to system's page release. > - */ > -static void kmem_freepages(struct kmem_cache *cachep, struct slab *slab) > -{ > - int order = cachep->gfporder; > - struct folio *folio = slab_folio(slab); > - > - BUG_ON(!folio_test_slab(folio)); > - __slab_clear_pfmemalloc(slab); > - page_mapcount_reset(&folio->page); > - folio->mapping = NULL; > - /* Make the mapping reset visible before clearing the flag */ > - smp_wmb(); > - __folio_clear_slab(folio); > - > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += 1 << order; > - unaccount_slab(slab, order, cachep); > - __free_pages(&folio->page, order); > -} > - > -static void kmem_rcu_free(struct rcu_head *head) > -{ > - struct kmem_cache *cachep; > - struct slab *slab; > - > - slab = container_of(head, struct slab, rcu_head); > - cachep = slab->slab_cache; > - > - kmem_freepages(cachep, slab); > -} > - > -#if DEBUG > -static inline bool is_debug_pagealloc_cache(struct kmem_cache *cachep) > -{ > - return debug_pagealloc_enabled_static() && OFF_SLAB(cachep) && > - ((cachep->size % PAGE_SIZE) == 0); > -} > - > -#ifdef CONFIG_DEBUG_PAGEALLOC > -static void slab_kernel_map(struct kmem_cache *cachep, void *objp, int map) > -{ > - if (!is_debug_pagealloc_cache(cachep)) > - return; > - > - __kernel_map_pages(virt_to_page(objp), cachep->size / PAGE_SIZE, map); > -} > - > -#else > -static inline void slab_kernel_map(struct kmem_cache *cachep, void *objp, > - int map) {} > - > -#endif > - > -static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val) > -{ > - int size = cachep->object_size; > - addr = &((char *)addr)[obj_offset(cachep)]; > - > - memset(addr, val, size); > - *(unsigned char *)(addr + size - 1) = POISON_END; > -} > - > -static void dump_line(char *data, int offset, int limit) > -{ > - int i; > - unsigned char error = 0; > - int bad_count = 0; > - > - pr_err("%03x: ", offset); > - for (i = 0; i < limit; i++) { > - if (data[offset + i] != POISON_FREE) { > - error = data[offset + i]; > - bad_count++; > - } > - } > - print_hex_dump(KERN_CONT, "", 0, 16, 1, > - &data[offset], limit, 1); > - > - if (bad_count == 1) { > - error ^= POISON_FREE; > - if (!(error & (error - 1))) { > - pr_err("Single bit error detected. Probably bad RAM.\n"); > -#ifdef CONFIG_X86 > - pr_err("Run memtest86+ or a similar memory test tool.\n"); > -#else > - pr_err("Run a memory test tool.\n"); > -#endif > - } > - } > -} > -#endif > - > -#if DEBUG > - > -static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines) > -{ > - int i, size; > - char *realobj; > - > - if (cachep->flags & SLAB_RED_ZONE) { > - pr_err("Redzone: 0x%llx/0x%llx\n", > - *dbg_redzone1(cachep, objp), > - *dbg_redzone2(cachep, objp)); > - } > - > - if (cachep->flags & SLAB_STORE_USER) > - pr_err("Last user: (%pSR)\n", *dbg_userword(cachep, objp)); > - realobj = (char *)objp + obj_offset(cachep); > - size = cachep->object_size; > - for (i = 0; i < size && lines; i += 16, lines--) { > - int limit; > - limit = 16; > - if (i + limit > size) > - limit = size - i; > - dump_line(realobj, i, limit); > - } > -} > - > -static void check_poison_obj(struct kmem_cache *cachep, void *objp) > -{ > - char *realobj; > - int size, i; > - int lines = 0; > - > - if (is_debug_pagealloc_cache(cachep)) > - return; > - > - realobj = (char *)objp + obj_offset(cachep); > - size = cachep->object_size; > - > - for (i = 0; i < size; i++) { > - char exp = POISON_FREE; > - if (i == size - 1) > - exp = POISON_END; > - if (realobj[i] != exp) { > - int limit; > - /* Mismatch ! */ > - /* Print header */ > - if (lines == 0) { > - pr_err("Slab corruption (%s): %s start=%px, len=%d\n", > - print_tainted(), cachep->name, > - realobj, size); > - print_objinfo(cachep, objp, 0); > - } > - /* Hexdump the affected line */ > - i = (i / 16) * 16; > - limit = 16; > - if (i + limit > size) > - limit = size - i; > - dump_line(realobj, i, limit); > - i += 16; > - lines++; > - /* Limit to 5 lines */ > - if (lines > 5) > - break; > - } > - } > - if (lines != 0) { > - /* Print some data about the neighboring objects, if they > - * exist: > - */ > - struct slab *slab = virt_to_slab(objp); > - unsigned int objnr; > - > - objnr = obj_to_index(cachep, slab, objp); > - if (objnr) { > - objp = index_to_obj(cachep, slab, objnr - 1); > - realobj = (char *)objp + obj_offset(cachep); > - pr_err("Prev obj: start=%px, len=%d\n", realobj, size); > - print_objinfo(cachep, objp, 2); > - } > - if (objnr + 1 < cachep->num) { > - objp = index_to_obj(cachep, slab, objnr + 1); > - realobj = (char *)objp + obj_offset(cachep); > - pr_err("Next obj: start=%px, len=%d\n", realobj, size); > - print_objinfo(cachep, objp, 2); > - } > - } > -} > -#endif > - > -#if DEBUG > -static void slab_destroy_debugcheck(struct kmem_cache *cachep, > - struct slab *slab) > -{ > - int i; > - > - if (OBJFREELIST_SLAB(cachep) && cachep->flags & SLAB_POISON) { > - poison_obj(cachep, slab->freelist - obj_offset(cachep), > - POISON_FREE); > - } > - > - for (i = 0; i < cachep->num; i++) { > - void *objp = index_to_obj(cachep, slab, i); > - > - if (cachep->flags & SLAB_POISON) { > - check_poison_obj(cachep, objp); > - slab_kernel_map(cachep, objp, 1); > - } > - if (cachep->flags & SLAB_RED_ZONE) { > - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "start of a freed object was overwritten"); > - if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "end of a freed object was overwritten"); > - } > - } > -} > -#else > -static void slab_destroy_debugcheck(struct kmem_cache *cachep, > - struct slab *slab) > -{ > -} > -#endif > - > -/** > - * slab_destroy - destroy and release all objects in a slab > - * @cachep: cache pointer being destroyed > - * @slab: slab being destroyed > - * > - * Destroy all the objs in a slab, and release the mem back to the system. > - * Before calling the slab must have been unlinked from the cache. The > - * kmem_cache_node ->list_lock is not held/needed. > - */ > -static void slab_destroy(struct kmem_cache *cachep, struct slab *slab) > -{ > - void *freelist; > - > - freelist = slab->freelist; > - slab_destroy_debugcheck(cachep, slab); > - if (unlikely(cachep->flags & SLAB_TYPESAFE_BY_RCU)) > - call_rcu(&slab->rcu_head, kmem_rcu_free); > - else > - kmem_freepages(cachep, slab); > - > - /* > - * From now on, we don't use freelist > - * although actual page can be freed in rcu context > - */ > - if (OFF_SLAB(cachep)) > - kfree(freelist); > -} > - > -/* > - * Update the size of the caches before calling slabs_destroy as it may > - * recursively call kfree. > - */ > -static void slabs_destroy(struct kmem_cache *cachep, struct list_head *list) > -{ > - struct slab *slab, *n; > - > - list_for_each_entry_safe(slab, n, list, slab_list) { > - list_del(&slab->slab_list); > - slab_destroy(cachep, slab); > - } > -} > - > -/** > - * calculate_slab_order - calculate size (page order) of slabs > - * @cachep: pointer to the cache that is being created > - * @size: size of objects to be created in this cache. > - * @flags: slab allocation flags > - * > - * Also calculates the number of objects per slab. > - * > - * This could be made much more intelligent. For now, try to avoid using > - * high order pages for slabs. When the gfp() functions are more friendly > - * towards high-order requests, this should be changed. > - * > - * Return: number of left-over bytes in a slab > - */ > -static size_t calculate_slab_order(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left_over = 0; > - int gfporder; > - > - for (gfporder = 0; gfporder <= KMALLOC_MAX_ORDER; gfporder++) { > - unsigned int num; > - size_t remainder; > - > - num = cache_estimate(gfporder, size, flags, &remainder); > - if (!num) > - continue; > - > - /* Can't handle number of objects more than SLAB_OBJ_MAX_NUM */ > - if (num > SLAB_OBJ_MAX_NUM) > - break; > - > - if (flags & CFLGS_OFF_SLAB) { > - struct kmem_cache *freelist_cache; > - size_t freelist_size; > - size_t freelist_cache_size; > - > - freelist_size = num * sizeof(freelist_idx_t); > - if (freelist_size > KMALLOC_MAX_CACHE_SIZE) { > - freelist_cache_size = PAGE_SIZE << get_order(freelist_size); > - } else { > - freelist_cache = kmalloc_slab(freelist_size, 0u); > - if (!freelist_cache) > - continue; > - freelist_cache_size = freelist_cache->size; > - > - /* > - * Needed to avoid possible looping condition > - * in cache_grow_begin() > - */ > - if (OFF_SLAB(freelist_cache)) > - continue; > - } > - > - /* check if off slab has enough benefit */ > - if (freelist_cache_size > cachep->size / 2) > - continue; > - } > - > - /* Found something acceptable - save it away */ > - cachep->num = num; > - cachep->gfporder = gfporder; > - left_over = remainder; > - > - /* > - * A VFS-reclaimable slab tends to have most allocations > - * as GFP_NOFS and we really don't want to have to be allocating > - * higher-order pages when we are unable to shrink dcache. > - */ > - if (flags & SLAB_RECLAIM_ACCOUNT) > - break; > - > - /* > - * Large number of objects is good, but very large slabs are > - * currently bad for the gfp()s. > - */ > - if (gfporder >= slab_max_order) > - break; > - > - /* > - * Acceptable internal fragmentation? > - */ > - if (left_over * 8 <= (PAGE_SIZE << gfporder)) > - break; > - } > - return left_over; > -} > - > -static struct array_cache __percpu *alloc_kmem_cache_cpus( > - struct kmem_cache *cachep, int entries, int batchcount) > -{ > - int cpu; > - size_t size; > - struct array_cache __percpu *cpu_cache; > - > - size = sizeof(void *) * entries + sizeof(struct array_cache); > - cpu_cache = __alloc_percpu(size, sizeof(void *)); > - > - if (!cpu_cache) > - return NULL; > - > - for_each_possible_cpu(cpu) { > - init_arraycache(per_cpu_ptr(cpu_cache, cpu), > - entries, batchcount); > - } > - > - return cpu_cache; > -} > - > -static int __ref setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp) > -{ > - if (slab_state >= FULL) > - return enable_cpucache(cachep, gfp); > - > - cachep->cpu_cache = alloc_kmem_cache_cpus(cachep, 1, 1); > - if (!cachep->cpu_cache) > - return 1; > - > - if (slab_state == DOWN) { > - /* Creation of first cache (kmem_cache). */ > - set_up_node(kmem_cache, CACHE_CACHE); > - } else if (slab_state == PARTIAL) { > - /* For kmem_cache_node */ > - set_up_node(cachep, SIZE_NODE); > - } else { > - int node; > - > - for_each_online_node(node) { > - cachep->node[node] = kmalloc_node( > - sizeof(struct kmem_cache_node), gfp, node); > - BUG_ON(!cachep->node[node]); > - kmem_cache_node_init(cachep->node[node]); > - } > - } > - > - cachep->node[numa_mem_id()]->next_reap = > - jiffies + REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - > - cpu_cache_get(cachep)->avail = 0; > - cpu_cache_get(cachep)->limit = BOOT_CPUCACHE_ENTRIES; > - cpu_cache_get(cachep)->batchcount = 1; > - cpu_cache_get(cachep)->touched = 0; > - cachep->batchcount = 1; > - cachep->limit = BOOT_CPUCACHE_ENTRIES; > - return 0; > -} > - > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name) > -{ > - return flags; > -} > - > -struct kmem_cache * > -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > - slab_flags_t flags, void (*ctor)(void *)) > -{ > - struct kmem_cache *cachep; > - > - cachep = find_mergeable(size, align, flags, name, ctor); > - if (cachep) { > - cachep->refcount++; > - > - /* > - * Adjust the object sizes so that we clear > - * the complete object on kzalloc. > - */ > - cachep->object_size = max_t(int, cachep->object_size, size); > - } > - return cachep; > -} > - > -static bool set_objfreelist_slab_cache(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left; > - > - cachep->num = 0; > - > - /* > - * If slab auto-initialization on free is enabled, store the freelist > - * off-slab, so that its contents don't end up in one of the allocated > - * objects. > - */ > - if (unlikely(slab_want_init_on_free(cachep))) > - return false; > - > - if (cachep->ctor || flags & SLAB_TYPESAFE_BY_RCU) > - return false; > - > - left = calculate_slab_order(cachep, size, > - flags | CFLGS_OBJFREELIST_SLAB); > - if (!cachep->num) > - return false; > - > - if (cachep->num * sizeof(freelist_idx_t) > cachep->object_size) > - return false; > - > - cachep->colour = left / cachep->colour_off; > - > - return true; > -} > - > -static bool set_off_slab_cache(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left; > - > - cachep->num = 0; > - > - /* > - * Always use on-slab management when SLAB_NOLEAKTRACE > - * to avoid recursive calls into kmemleak. > - */ > - if (flags & SLAB_NOLEAKTRACE) > - return false; > - > - /* > - * Size is large, assume best to place the slab management obj > - * off-slab (should allow better packing of objs). > - */ > - left = calculate_slab_order(cachep, size, flags | CFLGS_OFF_SLAB); > - if (!cachep->num) > - return false; > - > - /* > - * If the slab has been placed off-slab, and we have enough space then > - * move it on-slab. This is at the expense of any extra colouring. > - */ > - if (left >= cachep->num * sizeof(freelist_idx_t)) > - return false; > - > - cachep->colour = left / cachep->colour_off; > - > - return true; > -} > - > -static bool set_on_slab_cache(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left; > - > - cachep->num = 0; > - > - left = calculate_slab_order(cachep, size, flags); > - if (!cachep->num) > - return false; > - > - cachep->colour = left / cachep->colour_off; > - > - return true; > -} > - > -/** > - * __kmem_cache_create - Create a cache. > - * @cachep: cache management descriptor > - * @flags: SLAB flags > - * > - * Returns a ptr to the cache on success, NULL on failure. > - * Cannot be called within an int, but can be interrupted. > - * The @ctor is run when new pages are allocated by the cache. > - * > - * The flags are > - * > - * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5) > - * to catch references to uninitialised memory. > - * > - * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check > - * for buffer overruns. > - * > - * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware > - * cacheline. This can be beneficial if you're counting cycles as closely > - * as davem. > - * > - * Return: a pointer to the created cache or %NULL in case of error > - */ > -int __kmem_cache_create(struct kmem_cache *cachep, slab_flags_t flags) > -{ > - size_t ralign = BYTES_PER_WORD; > - gfp_t gfp; > - int err; > - unsigned int size = cachep->size; > - > -#if DEBUG > -#if FORCED_DEBUG > - /* > - * Enable redzoning and last user accounting, except for caches with > - * large objects, if the increased size would increase the object size > - * above the next power of two: caches with object sizes just above a > - * power of two have a significant amount of internal fragmentation. > - */ > - if (size < 4096 || fls(size - 1) == fls(size-1 + REDZONE_ALIGN + > - 2 * sizeof(unsigned long long))) > - flags |= SLAB_RED_ZONE | SLAB_STORE_USER; > - if (!(flags & SLAB_TYPESAFE_BY_RCU)) > - flags |= SLAB_POISON; > -#endif > -#endif > - > - /* > - * Check that size is in terms of words. This is needed to avoid > - * unaligned accesses for some archs when redzoning is used, and makes > - * sure any on-slab bufctl's are also correctly aligned. > - */ > - size = ALIGN(size, BYTES_PER_WORD); > - > - if (flags & SLAB_RED_ZONE) { > - ralign = REDZONE_ALIGN; > - /* If redzoning, ensure that the second redzone is suitably > - * aligned, by adjusting the object size accordingly. */ > - size = ALIGN(size, REDZONE_ALIGN); > - } > - > - /* 3) caller mandated alignment */ > - if (ralign < cachep->align) { > - ralign = cachep->align; > - } > - /* disable debug if necessary */ > - if (ralign > __alignof__(unsigned long long)) > - flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); > - /* > - * 4) Store it. > - */ > - cachep->align = ralign; > - cachep->colour_off = cache_line_size(); > - /* Offset must be a multiple of the alignment. */ > - if (cachep->colour_off < cachep->align) > - cachep->colour_off = cachep->align; > - > - if (slab_is_available()) > - gfp = GFP_KERNEL; > - else > - gfp = GFP_NOWAIT; > - > -#if DEBUG > - > - /* > - * Both debugging options require word-alignment which is calculated > - * into align above. > - */ > - if (flags & SLAB_RED_ZONE) { > - /* add space for red zone words */ > - cachep->obj_offset += sizeof(unsigned long long); > - size += 2 * sizeof(unsigned long long); > - } > - if (flags & SLAB_STORE_USER) { > - /* user store requires one word storage behind the end of > - * the real object. But if the second red zone needs to be > - * aligned to 64 bits, we must allow that much space. > - */ > - if (flags & SLAB_RED_ZONE) > - size += REDZONE_ALIGN; > - else > - size += BYTES_PER_WORD; > - } > -#endif > - > - kasan_cache_create(cachep, &size, &flags); > - > - size = ALIGN(size, cachep->align); > - /* > - * We should restrict the number of objects in a slab to implement > - * byte sized index. Refer comment on SLAB_OBJ_MIN_SIZE definition. > - */ > - if (FREELIST_BYTE_INDEX && size < SLAB_OBJ_MIN_SIZE) > - size = ALIGN(SLAB_OBJ_MIN_SIZE, cachep->align); > - > -#if DEBUG > - /* > - * To activate debug pagealloc, off-slab management is necessary > - * requirement. In early phase of initialization, small sized slab > - * doesn't get initialized so it would not be possible. So, we need > - * to check size >= 256. It guarantees that all necessary small > - * sized slab is initialized in current slab initialization sequence. > - */ > - if (debug_pagealloc_enabled_static() && (flags & SLAB_POISON) && > - size >= 256 && cachep->object_size > cache_line_size()) { > - if (size < PAGE_SIZE || size % PAGE_SIZE == 0) { > - size_t tmp_size = ALIGN(size, PAGE_SIZE); > - > - if (set_off_slab_cache(cachep, tmp_size, flags)) { > - flags |= CFLGS_OFF_SLAB; > - cachep->obj_offset += tmp_size - size; > - size = tmp_size; > - goto done; > - } > - } > - } > -#endif > - > - if (set_objfreelist_slab_cache(cachep, size, flags)) { > - flags |= CFLGS_OBJFREELIST_SLAB; > - goto done; > - } > - > - if (set_off_slab_cache(cachep, size, flags)) { > - flags |= CFLGS_OFF_SLAB; > - goto done; > - } > - > - if (set_on_slab_cache(cachep, size, flags)) > - goto done; > - > - return -E2BIG; > - > -done: > - cachep->freelist_size = cachep->num * sizeof(freelist_idx_t); > - cachep->flags = flags; > - cachep->allocflags = __GFP_COMP; > - if (flags & SLAB_CACHE_DMA) > - cachep->allocflags |= GFP_DMA; > - if (flags & SLAB_CACHE_DMA32) > - cachep->allocflags |= GFP_DMA32; > - if (flags & SLAB_RECLAIM_ACCOUNT) > - cachep->allocflags |= __GFP_RECLAIMABLE; > - cachep->size = size; > - cachep->reciprocal_buffer_size = reciprocal_value(size); > - > -#if DEBUG > - /* > - * If we're going to use the generic kernel_map_pages() > - * poisoning, then it's going to smash the contents of > - * the redzone and userword anyhow, so switch them off. > - */ > - if (IS_ENABLED(CONFIG_PAGE_POISONING) && > - (cachep->flags & SLAB_POISON) && > - is_debug_pagealloc_cache(cachep)) > - cachep->flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); > -#endif > - > - err = setup_cpu_cache(cachep, gfp); > - if (err) { > - __kmem_cache_release(cachep); > - return err; > - } > - > - return 0; > -} > - > -#if DEBUG > -static void check_irq_off(void) > -{ > - BUG_ON(!irqs_disabled()); > -} > - > -static void check_irq_on(void) > -{ > - BUG_ON(irqs_disabled()); > -} > - > -static void check_mutex_acquired(void) > -{ > - BUG_ON(!mutex_is_locked(&slab_mutex)); > -} > - > -static void check_spinlock_acquired(struct kmem_cache *cachep) > -{ > -#ifdef CONFIG_SMP > - check_irq_off(); > - assert_raw_spin_locked(&get_node(cachep, numa_mem_id())->list_lock); > -#endif > -} > - > -static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node) > -{ > -#ifdef CONFIG_SMP > - check_irq_off(); > - assert_raw_spin_locked(&get_node(cachep, node)->list_lock); > -#endif > -} > - > -#else > -#define check_irq_off() do { } while(0) > -#define check_irq_on() do { } while(0) > -#define check_mutex_acquired() do { } while(0) > -#define check_spinlock_acquired(x) do { } while(0) > -#define check_spinlock_acquired_node(x, y) do { } while(0) > -#endif > - > -static void drain_array_locked(struct kmem_cache *cachep, struct array_cache *ac, > - int node, bool free_all, struct list_head *list) > -{ > - int tofree; > - > - if (!ac || !ac->avail) > - return; > - > - tofree = free_all ? ac->avail : (ac->limit + 4) / 5; > - if (tofree > ac->avail) > - tofree = (ac->avail + 1) / 2; > - > - free_block(cachep, ac->entry, tofree, node, list); > - ac->avail -= tofree; > - memmove(ac->entry, &(ac->entry[tofree]), sizeof(void *) * ac->avail); > -} > - > -static void do_drain(void *arg) > -{ > - struct kmem_cache *cachep = arg; > - struct array_cache *ac; > - int node = numa_mem_id(); > - struct kmem_cache_node *n; > - LIST_HEAD(list); > - > - check_irq_off(); > - ac = cpu_cache_get(cachep); > - n = get_node(cachep, node); > - raw_spin_lock(&n->list_lock); > - free_block(cachep, ac->entry, ac->avail, node, &list); > - raw_spin_unlock(&n->list_lock); > - ac->avail = 0; > - slabs_destroy(cachep, &list); > -} > - > -static void drain_cpu_caches(struct kmem_cache *cachep) > -{ > - struct kmem_cache_node *n; > - int node; > - LIST_HEAD(list); > - > - on_each_cpu(do_drain, cachep, 1); > - check_irq_on(); > - for_each_kmem_cache_node(cachep, node, n) > - if (n->alien) > - drain_alien_cache(cachep, n->alien); > - > - for_each_kmem_cache_node(cachep, node, n) { > - raw_spin_lock_irq(&n->list_lock); > - drain_array_locked(cachep, n->shared, node, true, &list); > - raw_spin_unlock_irq(&n->list_lock); > - > - slabs_destroy(cachep, &list); > - } > -} > - > -/* > - * Remove slabs from the list of free slabs. > - * Specify the number of slabs to drain in tofree. > - * > - * Returns the actual number of slabs released. > - */ > -static int drain_freelist(struct kmem_cache *cache, > - struct kmem_cache_node *n, int tofree) > -{ > - struct list_head *p; > - int nr_freed; > - struct slab *slab; > - > - nr_freed = 0; > - while (nr_freed < tofree && !list_empty(&n->slabs_free)) { > - > - raw_spin_lock_irq(&n->list_lock); > - p = n->slabs_free.prev; > - if (p == &n->slabs_free) { > - raw_spin_unlock_irq(&n->list_lock); > - goto out; > - } > - > - slab = list_entry(p, struct slab, slab_list); > - list_del(&slab->slab_list); > - n->free_slabs--; > - n->total_slabs--; > - /* > - * Safe to drop the lock. The slab is no longer linked > - * to the cache. > - */ > - n->free_objects -= cache->num; > - raw_spin_unlock_irq(&n->list_lock); > - slab_destroy(cache, slab); > - nr_freed++; > - > - cond_resched(); > - } > -out: > - return nr_freed; > -} > - > -bool __kmem_cache_empty(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) > - if (!list_empty(&n->slabs_full) || > - !list_empty(&n->slabs_partial)) > - return false; > - return true; > -} > - > -int __kmem_cache_shrink(struct kmem_cache *cachep) > -{ > - int ret = 0; > - int node; > - struct kmem_cache_node *n; > - > - drain_cpu_caches(cachep); > - > - check_irq_on(); > - for_each_kmem_cache_node(cachep, node, n) { > - drain_freelist(cachep, n, INT_MAX); > - > - ret += !list_empty(&n->slabs_full) || > - !list_empty(&n->slabs_partial); > - } > - return (ret ? 1 : 0); > -} > - > -int __kmem_cache_shutdown(struct kmem_cache *cachep) > -{ > - return __kmem_cache_shrink(cachep); > -} > - > -void __kmem_cache_release(struct kmem_cache *cachep) > -{ > - int i; > - struct kmem_cache_node *n; > - > - cache_random_seq_destroy(cachep); > - > - free_percpu(cachep->cpu_cache); > - > - /* NUMA: free the node structures */ > - for_each_kmem_cache_node(cachep, i, n) { > - kfree(n->shared); > - free_alien_cache(n->alien); > - kfree(n); > - cachep->node[i] = NULL; > - } > -} > - > -/* > - * Get the memory for a slab management obj. > - * > - * For a slab cache when the slab descriptor is off-slab, the > - * slab descriptor can't come from the same cache which is being created, > - * Because if it is the case, that means we defer the creation of > - * the kmalloc_{dma,}_cache of size sizeof(slab descriptor) to this point. > - * And we eventually call down to __kmem_cache_create(), which > - * in turn looks up in the kmalloc_{dma,}_caches for the desired-size one. > - * This is a "chicken-and-egg" problem. > - * > - * So the off-slab slab descriptor shall come from the kmalloc_{dma,}_caches, > - * which are all initialized during kmem_cache_init(). > - */ > -static void *alloc_slabmgmt(struct kmem_cache *cachep, > - struct slab *slab, int colour_off, > - gfp_t local_flags, int nodeid) > -{ > - void *freelist; > - void *addr = slab_address(slab); > - > - slab->s_mem = addr + colour_off; > - slab->active = 0; > - > - if (OBJFREELIST_SLAB(cachep)) > - freelist = NULL; > - else if (OFF_SLAB(cachep)) { > - /* Slab management obj is off-slab. */ > - freelist = kmalloc_node(cachep->freelist_size, > - local_flags, nodeid); > - } else { > - /* We will use last bytes at the slab for freelist */ > - freelist = addr + (PAGE_SIZE << cachep->gfporder) - > - cachep->freelist_size; > - } > - > - return freelist; > -} > - > -static inline freelist_idx_t get_free_obj(struct slab *slab, unsigned int idx) > -{ > - return ((freelist_idx_t *) slab->freelist)[idx]; > -} > - > -static inline void set_free_obj(struct slab *slab, > - unsigned int idx, freelist_idx_t val) > -{ > - ((freelist_idx_t *)(slab->freelist))[idx] = val; > -} > - > -static void cache_init_objs_debug(struct kmem_cache *cachep, struct slab *slab) > -{ > -#if DEBUG > - int i; > - > - for (i = 0; i < cachep->num; i++) { > - void *objp = index_to_obj(cachep, slab, i); > - > - if (cachep->flags & SLAB_STORE_USER) > - *dbg_userword(cachep, objp) = NULL; > - > - if (cachep->flags & SLAB_RED_ZONE) { > - *dbg_redzone1(cachep, objp) = RED_INACTIVE; > - *dbg_redzone2(cachep, objp) = RED_INACTIVE; > - } > - /* > - * Constructors are not allowed to allocate memory from the same > - * cache which they are a constructor for. Otherwise, deadlock. > - * They must also be threaded. > - */ > - if (cachep->ctor && !(cachep->flags & SLAB_POISON)) { > - kasan_unpoison_object_data(cachep, > - objp + obj_offset(cachep)); > - cachep->ctor(objp + obj_offset(cachep)); > - kasan_poison_object_data( > - cachep, objp + obj_offset(cachep)); > - } > - > - if (cachep->flags & SLAB_RED_ZONE) { > - if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "constructor overwrote the end of an object"); > - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "constructor overwrote the start of an object"); > - } > - /* need to poison the objs? */ > - if (cachep->flags & SLAB_POISON) { > - poison_obj(cachep, objp, POISON_FREE); > - slab_kernel_map(cachep, objp, 0); > - } > - } > -#endif > -} > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -/* Hold information during a freelist initialization */ > -union freelist_init_state { > - struct { > - unsigned int pos; > - unsigned int *list; > - unsigned int count; > - }; > - struct rnd_state rnd_state; > -}; > - > -/* > - * Initialize the state based on the randomization method available. > - * return true if the pre-computed list is available, false otherwise. > - */ > -static bool freelist_state_initialize(union freelist_init_state *state, > - struct kmem_cache *cachep, > - unsigned int count) > -{ > - bool ret; > - unsigned int rand; > - > - /* Use best entropy available to define a random shift */ > - rand = get_random_u32(); > - > - /* Use a random state if the pre-computed list is not available */ > - if (!cachep->random_seq) { > - prandom_seed_state(&state->rnd_state, rand); > - ret = false; > - } else { > - state->list = cachep->random_seq; > - state->count = count; > - state->pos = rand % count; > - ret = true; > - } > - return ret; > -} > - > -/* Get the next entry on the list and randomize it using a random shift */ > -static freelist_idx_t next_random_slot(union freelist_init_state *state) > -{ > - if (state->pos >= state->count) > - state->pos = 0; > - return state->list[state->pos++]; > -} > - > -/* Swap two freelist entries */ > -static void swap_free_obj(struct slab *slab, unsigned int a, unsigned int b) > -{ > - swap(((freelist_idx_t *) slab->freelist)[a], > - ((freelist_idx_t *) slab->freelist)[b]); > -} > - > -/* > - * Shuffle the freelist initialization state based on pre-computed lists. > - * return true if the list was successfully shuffled, false otherwise. > - */ > -static bool shuffle_freelist(struct kmem_cache *cachep, struct slab *slab) > -{ > - unsigned int objfreelist = 0, i, rand, count = cachep->num; > - union freelist_init_state state; > - bool precomputed; > - > - if (count < 2) > - return false; > - > - precomputed = freelist_state_initialize(&state, cachep, count); > - > - /* Take a random entry as the objfreelist */ > - if (OBJFREELIST_SLAB(cachep)) { > - if (!precomputed) > - objfreelist = count - 1; > - else > - objfreelist = next_random_slot(&state); > - slab->freelist = index_to_obj(cachep, slab, objfreelist) + > - obj_offset(cachep); > - count--; > - } > - > - /* > - * On early boot, generate the list dynamically. > - * Later use a pre-computed list for speed. > - */ > - if (!precomputed) { > - for (i = 0; i < count; i++) > - set_free_obj(slab, i, i); > - > - /* Fisher-Yates shuffle */ > - for (i = count - 1; i > 0; i--) { > - rand = prandom_u32_state(&state.rnd_state); > - rand %= (i + 1); > - swap_free_obj(slab, i, rand); > - } > - } else { > - for (i = 0; i < count; i++) > - set_free_obj(slab, i, next_random_slot(&state)); > - } > - > - if (OBJFREELIST_SLAB(cachep)) > - set_free_obj(slab, cachep->num - 1, objfreelist); > - > - return true; > -} > -#else > -static inline bool shuffle_freelist(struct kmem_cache *cachep, > - struct slab *slab) > -{ > - return false; > -} > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > - > -static void cache_init_objs(struct kmem_cache *cachep, > - struct slab *slab) > -{ > - int i; > - void *objp; > - bool shuffled; > - > - cache_init_objs_debug(cachep, slab); > - > - /* Try to randomize the freelist if enabled */ > - shuffled = shuffle_freelist(cachep, slab); > - > - if (!shuffled && OBJFREELIST_SLAB(cachep)) { > - slab->freelist = index_to_obj(cachep, slab, cachep->num - 1) + > - obj_offset(cachep); > - } > - > - for (i = 0; i < cachep->num; i++) { > - objp = index_to_obj(cachep, slab, i); > - objp = kasan_init_slab_obj(cachep, objp); > - > - /* constructor could break poison info */ > - if (DEBUG == 0 && cachep->ctor) { > - kasan_unpoison_object_data(cachep, objp); > - cachep->ctor(objp); > - kasan_poison_object_data(cachep, objp); > - } > - > - if (!shuffled) > - set_free_obj(slab, i, i); > - } > -} > - > -static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slab) > -{ > - void *objp; > - > - objp = index_to_obj(cachep, slab, get_free_obj(slab, slab->active)); > - slab->active++; > - > - return objp; > -} > - > -static void slab_put_obj(struct kmem_cache *cachep, > - struct slab *slab, void *objp) > -{ > - unsigned int objnr = obj_to_index(cachep, slab, objp); > -#if DEBUG > - unsigned int i; > - > - /* Verify double free bug */ > - for (i = slab->active; i < cachep->num; i++) { > - if (get_free_obj(slab, i) == objnr) { > - pr_err("slab: double free detected in cache '%s', objp %px\n", > - cachep->name, objp); > - BUG(); > - } > - } > -#endif > - slab->active--; > - if (!slab->freelist) > - slab->freelist = objp + obj_offset(cachep); > - > - set_free_obj(slab, slab->active, objnr); > -} > - > -/* > - * Grow (by 1) the number of slabs within a cache. This is called by > - * kmem_cache_alloc() when there are no active objs left in a cache. > - */ > -static struct slab *cache_grow_begin(struct kmem_cache *cachep, > - gfp_t flags, int nodeid) > -{ > - void *freelist; > - size_t offset; > - gfp_t local_flags; > - int slab_node; > - struct kmem_cache_node *n; > - struct slab *slab; > - > - /* > - * Be lazy and only check for valid flags here, keeping it out of the > - * critical path in kmem_cache_alloc(). > - */ > - if (unlikely(flags & GFP_SLAB_BUG_MASK)) > - flags = kmalloc_fix_flags(flags); > - > - WARN_ON_ONCE(cachep->ctor && (flags & __GFP_ZERO)); > - local_flags = flags & (GFP_CONSTRAINT_MASK|GFP_RECLAIM_MASK); > - > - check_irq_off(); > - if (gfpflags_allow_blocking(local_flags)) > - local_irq_enable(); > - > - /* > - * Get mem for the objs. Attempt to allocate a physical page from > - * 'nodeid'. > - */ > - slab = kmem_getpages(cachep, local_flags, nodeid); > - if (!slab) > - goto failed; > - > - slab_node = slab_nid(slab); > - n = get_node(cachep, slab_node); > - > - /* Get colour for the slab, and cal the next value. */ > - n->colour_next++; > - if (n->colour_next >= cachep->colour) > - n->colour_next = 0; > - > - offset = n->colour_next; > - if (offset >= cachep->colour) > - offset = 0; > - > - offset *= cachep->colour_off; > - > - /* > - * Call kasan_poison_slab() before calling alloc_slabmgmt(), so > - * page_address() in the latter returns a non-tagged pointer, > - * as it should be for slab pages. > - */ > - kasan_poison_slab(slab); > - > - /* Get slab management. */ > - freelist = alloc_slabmgmt(cachep, slab, offset, > - local_flags & ~GFP_CONSTRAINT_MASK, slab_node); > - if (OFF_SLAB(cachep) && !freelist) > - goto opps1; > - > - slab->slab_cache = cachep; > - slab->freelist = freelist; > - > - cache_init_objs(cachep, slab); > - > - if (gfpflags_allow_blocking(local_flags)) > - local_irq_disable(); > - > - return slab; > - > -opps1: > - kmem_freepages(cachep, slab); > -failed: > - if (gfpflags_allow_blocking(local_flags)) > - local_irq_disable(); > - return NULL; > -} > - > -static void cache_grow_end(struct kmem_cache *cachep, struct slab *slab) > -{ > - struct kmem_cache_node *n; > - void *list = NULL; > - > - check_irq_off(); > - > - if (!slab) > - return; > - > - INIT_LIST_HEAD(&slab->slab_list); > - n = get_node(cachep, slab_nid(slab)); > - > - raw_spin_lock(&n->list_lock); > - n->total_slabs++; > - if (!slab->active) { > - list_add_tail(&slab->slab_list, &n->slabs_free); > - n->free_slabs++; > - } else > - fixup_slab_list(cachep, n, slab, &list); > - > - STATS_INC_GROWN(cachep); > - n->free_objects += cachep->num - slab->active; > - raw_spin_unlock(&n->list_lock); > - > - fixup_objfreelist_debug(cachep, &list); > -} > - > -#if DEBUG > - > -/* > - * Perform extra freeing checks: > - * - detect bad pointers. > - * - POISON/RED_ZONE checking > - */ > -static void kfree_debugcheck(const void *objp) > -{ > - if (!virt_addr_valid(objp)) { > - pr_err("kfree_debugcheck: out of range ptr %lxh\n", > - (unsigned long)objp); > - BUG(); > - } > -} > - > -static inline void verify_redzone_free(struct kmem_cache *cache, void *obj) > -{ > - unsigned long long redzone1, redzone2; > - > - redzone1 = *dbg_redzone1(cache, obj); > - redzone2 = *dbg_redzone2(cache, obj); > - > - /* > - * Redzone is ok. > - */ > - if (redzone1 == RED_ACTIVE && redzone2 == RED_ACTIVE) > - return; > - > - if (redzone1 == RED_INACTIVE && redzone2 == RED_INACTIVE) > - slab_error(cache, "double free detected"); > - else > - slab_error(cache, "memory outside object was overwritten"); > - > - pr_err("%px: redzone 1:0x%llx, redzone 2:0x%llx\n", > - obj, redzone1, redzone2); > -} > - > -static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - unsigned int objnr; > - struct slab *slab; > - > - BUG_ON(virt_to_cache(objp) != cachep); > - > - objp -= obj_offset(cachep); > - kfree_debugcheck(objp); > - slab = virt_to_slab(objp); > - > - if (cachep->flags & SLAB_RED_ZONE) { > - verify_redzone_free(cachep, objp); > - *dbg_redzone1(cachep, objp) = RED_INACTIVE; > - *dbg_redzone2(cachep, objp) = RED_INACTIVE; > - } > - if (cachep->flags & SLAB_STORE_USER) > - *dbg_userword(cachep, objp) = (void *)caller; > - > - objnr = obj_to_index(cachep, slab, objp); > - > - BUG_ON(objnr >= cachep->num); > - BUG_ON(objp != index_to_obj(cachep, slab, objnr)); > - > - if (cachep->flags & SLAB_POISON) { > - poison_obj(cachep, objp, POISON_FREE); > - slab_kernel_map(cachep, objp, 0); > - } > - return objp; > -} > - > -#else > -#define kfree_debugcheck(x) do { } while(0) > -#define cache_free_debugcheck(x, objp, z) (objp) > -#endif > - > -static inline void fixup_objfreelist_debug(struct kmem_cache *cachep, > - void **list) > -{ > -#if DEBUG > - void *next = *list; > - void *objp; > - > - while (next) { > - objp = next - obj_offset(cachep); > - next = *(void **)next; > - poison_obj(cachep, objp, POISON_FREE); > - } > -#endif > -} > - > -static inline void fixup_slab_list(struct kmem_cache *cachep, > - struct kmem_cache_node *n, struct slab *slab, > - void **list) > -{ > - /* move slabp to correct slabp list: */ > - list_del(&slab->slab_list); > - if (slab->active == cachep->num) { > - list_add(&slab->slab_list, &n->slabs_full); > - if (OBJFREELIST_SLAB(cachep)) { > -#if DEBUG > - /* Poisoning will be done without holding the lock */ > - if (cachep->flags & SLAB_POISON) { > - void **objp = slab->freelist; > - > - *objp = *list; > - *list = objp; > - } > -#endif > - slab->freelist = NULL; > - } > - } else > - list_add(&slab->slab_list, &n->slabs_partial); > -} > - > -/* Try to find non-pfmemalloc slab if needed */ > -static noinline struct slab *get_valid_first_slab(struct kmem_cache_node *n, > - struct slab *slab, bool pfmemalloc) > -{ > - if (!slab) > - return NULL; > - > - if (pfmemalloc) > - return slab; > - > - if (!slab_test_pfmemalloc(slab)) > - return slab; > - > - /* No need to keep pfmemalloc slab if we have enough free objects */ > - if (n->free_objects > n->free_limit) { > - slab_clear_pfmemalloc(slab); > - return slab; > - } > - > - /* Move pfmemalloc slab to the end of list to speed up next search */ > - list_del(&slab->slab_list); > - if (!slab->active) { > - list_add_tail(&slab->slab_list, &n->slabs_free); > - n->free_slabs++; > - } else > - list_add_tail(&slab->slab_list, &n->slabs_partial); > - > - list_for_each_entry(slab, &n->slabs_partial, slab_list) { > - if (!slab_test_pfmemalloc(slab)) > - return slab; > - } > - > - n->free_touched = 1; > - list_for_each_entry(slab, &n->slabs_free, slab_list) { > - if (!slab_test_pfmemalloc(slab)) { > - n->free_slabs--; > - return slab; > - } > - } > - > - return NULL; > -} > - > -static struct slab *get_first_slab(struct kmem_cache_node *n, bool pfmemalloc) > -{ > - struct slab *slab; > - > - assert_raw_spin_locked(&n->list_lock); > - slab = list_first_entry_or_null(&n->slabs_partial, struct slab, > - slab_list); > - if (!slab) { > - n->free_touched = 1; > - slab = list_first_entry_or_null(&n->slabs_free, struct slab, > - slab_list); > - if (slab) > - n->free_slabs--; > - } > - > - if (sk_memalloc_socks()) > - slab = get_valid_first_slab(n, slab, pfmemalloc); > - > - return slab; > -} > - > -static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep, > - struct kmem_cache_node *n, gfp_t flags) > -{ > - struct slab *slab; > - void *obj; > - void *list = NULL; > - > - if (!gfp_pfmemalloc_allowed(flags)) > - return NULL; > - > - raw_spin_lock(&n->list_lock); > - slab = get_first_slab(n, true); > - if (!slab) { > - raw_spin_unlock(&n->list_lock); > - return NULL; > - } > - > - obj = slab_get_obj(cachep, slab); > - n->free_objects--; > - > - fixup_slab_list(cachep, n, slab, &list); > - > - raw_spin_unlock(&n->list_lock); > - fixup_objfreelist_debug(cachep, &list); > - > - return obj; > -} > - > -/* > - * Slab list should be fixed up by fixup_slab_list() for existing slab > - * or cache_grow_end() for new slab > - */ > -static __always_inline int alloc_block(struct kmem_cache *cachep, > - struct array_cache *ac, struct slab *slab, int batchcount) > -{ > - /* > - * There must be at least one object available for > - * allocation. > - */ > - BUG_ON(slab->active >= cachep->num); > - > - while (slab->active < cachep->num && batchcount--) { > - STATS_INC_ALLOCED(cachep); > - STATS_INC_ACTIVE(cachep); > - STATS_SET_HIGH(cachep); > - > - ac->entry[ac->avail++] = slab_get_obj(cachep, slab); > - } > - > - return batchcount; > -} > - > -static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags) > -{ > - int batchcount; > - struct kmem_cache_node *n; > - struct array_cache *ac, *shared; > - int node; > - void *list = NULL; > - struct slab *slab; > - > - check_irq_off(); > - node = numa_mem_id(); > - > - ac = cpu_cache_get(cachep); > - batchcount = ac->batchcount; > - if (!ac->touched && batchcount > BATCHREFILL_LIMIT) { > - /* > - * If there was little recent activity on this cache, then > - * perform only a partial refill. Otherwise we could generate > - * refill bouncing. > - */ > - batchcount = BATCHREFILL_LIMIT; > - } > - n = get_node(cachep, node); > - > - BUG_ON(ac->avail > 0 || !n); > - shared = READ_ONCE(n->shared); > - if (!n->free_objects && (!shared || !shared->avail)) > - goto direct_grow; > - > - raw_spin_lock(&n->list_lock); > - shared = READ_ONCE(n->shared); > - > - /* See if we can refill from the shared array */ > - if (shared && transfer_objects(ac, shared, batchcount)) { > - shared->touched = 1; > - goto alloc_done; > - } > - > - while (batchcount > 0) { > - /* Get slab alloc is to come from. */ > - slab = get_first_slab(n, false); > - if (!slab) > - goto must_grow; > - > - check_spinlock_acquired(cachep); > - > - batchcount = alloc_block(cachep, ac, slab, batchcount); > - fixup_slab_list(cachep, n, slab, &list); > - } > - > -must_grow: > - n->free_objects -= ac->avail; > -alloc_done: > - raw_spin_unlock(&n->list_lock); > - fixup_objfreelist_debug(cachep, &list); > - > -direct_grow: > - if (unlikely(!ac->avail)) { > - /* Check if we can use obj in pfmemalloc slab */ > - if (sk_memalloc_socks()) { > - void *obj = cache_alloc_pfmemalloc(cachep, n, flags); > - > - if (obj) > - return obj; > - } > - > - slab = cache_grow_begin(cachep, gfp_exact_node(flags), node); > - > - /* > - * cache_grow_begin() can reenable interrupts, > - * then ac could change. > - */ > - ac = cpu_cache_get(cachep); > - if (!ac->avail && slab) > - alloc_block(cachep, ac, slab, batchcount); > - cache_grow_end(cachep, slab); > - > - if (!ac->avail) > - return NULL; > - } > - ac->touched = 1; > - > - return ac->entry[--ac->avail]; > -} > - > -#if DEBUG > -static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, > - gfp_t flags, void *objp, unsigned long caller) > -{ > - WARN_ON_ONCE(cachep->ctor && (flags & __GFP_ZERO)); > - if (!objp || is_kfence_address(objp)) > - return objp; > - if (cachep->flags & SLAB_POISON) { > - check_poison_obj(cachep, objp); > - slab_kernel_map(cachep, objp, 1); > - poison_obj(cachep, objp, POISON_INUSE); > - } > - if (cachep->flags & SLAB_STORE_USER) > - *dbg_userword(cachep, objp) = (void *)caller; > - > - if (cachep->flags & SLAB_RED_ZONE) { > - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE || > - *dbg_redzone2(cachep, objp) != RED_INACTIVE) { > - slab_error(cachep, "double free, or memory outside object was overwritten"); > - pr_err("%px: redzone 1:0x%llx, redzone 2:0x%llx\n", > - objp, *dbg_redzone1(cachep, objp), > - *dbg_redzone2(cachep, objp)); > - } > - *dbg_redzone1(cachep, objp) = RED_ACTIVE; > - *dbg_redzone2(cachep, objp) = RED_ACTIVE; > - } > - > - objp += obj_offset(cachep); > - if (cachep->ctor && cachep->flags & SLAB_POISON) > - cachep->ctor(objp); > - if ((unsigned long)objp & (arch_slab_minalign() - 1)) { > - pr_err("0x%px: not aligned to arch_slab_minalign()=%u\n", objp, > - arch_slab_minalign()); > - } > - return objp; > -} > -#else > -#define cache_alloc_debugcheck_after(a, b, objp, d) (objp) > -#endif > - > -static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - void *objp; > - struct array_cache *ac; > - > - check_irq_off(); > - > - ac = cpu_cache_get(cachep); > - if (likely(ac->avail)) { > - ac->touched = 1; > - objp = ac->entry[--ac->avail]; > - > - STATS_INC_ALLOCHIT(cachep); > - goto out; > - } > - > - STATS_INC_ALLOCMISS(cachep); > - objp = cache_alloc_refill(cachep, flags); > - /* > - * the 'ac' may be updated by cache_alloc_refill(), > - * and kmemleak_erase() requires its correct value. > - */ > - ac = cpu_cache_get(cachep); > - > -out: > - /* > - * To avoid a false negative, if an object that is in one of the > - * per-CPU caches is leaked, we need to make sure kmemleak doesn't > - * treat the array pointers as a reference to the object. > - */ > - if (objp) > - kmemleak_erase(&ac->entry[ac->avail]); > - return objp; > -} > - > -#ifdef CONFIG_NUMA > -static void *____cache_alloc_node(struct kmem_cache *, gfp_t, int); > - > -/* > - * Try allocating on another node if PFA_SPREAD_SLAB is a mempolicy is set. > - * > - * If we are in_interrupt, then process context, including cpusets and > - * mempolicy, may not apply and should not be used for allocation policy. > - */ > -static void *alternate_node_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - int nid_alloc, nid_here; > - > - if (in_interrupt() || (flags & __GFP_THISNODE)) > - return NULL; > - nid_alloc = nid_here = numa_mem_id(); > - if (cpuset_do_slab_mem_spread() && (cachep->flags & SLAB_MEM_SPREAD)) > - nid_alloc = cpuset_slab_spread_node(); > - else if (current->mempolicy) > - nid_alloc = mempolicy_slab_node(); > - if (nid_alloc != nid_here) > - return ____cache_alloc_node(cachep, flags, nid_alloc); > - return NULL; > -} > - > -/* > - * Fallback function if there was no memory available and no objects on a > - * certain node and fall back is permitted. First we scan all the > - * available node for available objects. If that fails then we > - * perform an allocation without specifying a node. This allows the page > - * allocator to do its reclaim / fallback magic. We then insert the > - * slab into the proper nodelist and then allocate from it. > - */ > -static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags) > -{ > - struct zonelist *zonelist; > - struct zoneref *z; > - struct zone *zone; > - enum zone_type highest_zoneidx = gfp_zone(flags); > - void *obj = NULL; > - struct slab *slab; > - int nid; > - unsigned int cpuset_mems_cookie; > - > - if (flags & __GFP_THISNODE) > - return NULL; > - > -retry_cpuset: > - cpuset_mems_cookie = read_mems_allowed_begin(); > - zonelist = node_zonelist(mempolicy_slab_node(), flags); > - > -retry: > - /* > - * Look through allowed nodes for objects available > - * from existing per node queues. > - */ > - for_each_zone_zonelist(zone, z, zonelist, highest_zoneidx) { > - nid = zone_to_nid(zone); > - > - if (cpuset_zone_allowed(zone, flags) && > - get_node(cache, nid) && > - get_node(cache, nid)->free_objects) { > - obj = ____cache_alloc_node(cache, > - gfp_exact_node(flags), nid); > - if (obj) > - break; > - } > - } > - > - if (!obj) { > - /* > - * This allocation will be performed within the constraints > - * of the current cpuset / memory policy requirements. > - * We may trigger various forms of reclaim on the allowed > - * set and go into memory reserves if necessary. > - */ > - slab = cache_grow_begin(cache, flags, numa_mem_id()); > - cache_grow_end(cache, slab); > - if (slab) { > - nid = slab_nid(slab); > - obj = ____cache_alloc_node(cache, > - gfp_exact_node(flags), nid); > - > - /* > - * Another processor may allocate the objects in > - * the slab since we are not holding any locks. > - */ > - if (!obj) > - goto retry; > - } > - } > - > - if (unlikely(!obj && read_mems_allowed_retry(cpuset_mems_cookie))) > - goto retry_cpuset; > - return obj; > -} > - > -/* > - * An interface to enable slab creation on nodeid > - */ > -static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, > - int nodeid) > -{ > - struct slab *slab; > - struct kmem_cache_node *n; > - void *obj = NULL; > - void *list = NULL; > - > - VM_BUG_ON(nodeid < 0 || nodeid >= MAX_NUMNODES); > - n = get_node(cachep, nodeid); > - BUG_ON(!n); > - > - check_irq_off(); > - raw_spin_lock(&n->list_lock); > - slab = get_first_slab(n, false); > - if (!slab) > - goto must_grow; > - > - check_spinlock_acquired_node(cachep, nodeid); > - > - STATS_INC_NODEALLOCS(cachep); > - STATS_INC_ACTIVE(cachep); > - STATS_SET_HIGH(cachep); > - > - BUG_ON(slab->active == cachep->num); > - > - obj = slab_get_obj(cachep, slab); > - n->free_objects--; > - > - fixup_slab_list(cachep, n, slab, &list); > - > - raw_spin_unlock(&n->list_lock); > - fixup_objfreelist_debug(cachep, &list); > - return obj; > - > -must_grow: > - raw_spin_unlock(&n->list_lock); > - slab = cache_grow_begin(cachep, gfp_exact_node(flags), nodeid); > - if (slab) { > - /* This slab isn't counted yet so don't update free_objects */ > - obj = slab_get_obj(cachep, slab); > - } > - cache_grow_end(cachep, slab); > - > - return obj ? obj : fallback_alloc(cachep, flags); > -} > - > -static __always_inline void * > -__do_cache_alloc(struct kmem_cache *cachep, gfp_t flags, int nodeid) > -{ > - void *objp = NULL; > - int slab_node = numa_mem_id(); > - > - if (nodeid == NUMA_NO_NODE) { > - if (current->mempolicy || cpuset_do_slab_mem_spread()) { > - objp = alternate_node_alloc(cachep, flags); > - if (objp) > - goto out; > - } > - /* > - * Use the locally cached objects if possible. > - * However ____cache_alloc does not allow fallback > - * to other nodes. It may fail while we still have > - * objects on other nodes available. > - */ > - objp = ____cache_alloc(cachep, flags); > - nodeid = slab_node; > - } else if (nodeid == slab_node) { > - objp = ____cache_alloc(cachep, flags); > - } else if (!get_node(cachep, nodeid)) { > - /* Node not bootstrapped yet */ > - objp = fallback_alloc(cachep, flags); > - goto out; > - } > - > - /* > - * We may just have run out of memory on the local node. > - * ____cache_alloc_node() knows how to locate memory on other nodes > - */ > - if (!objp) > - objp = ____cache_alloc_node(cachep, flags, nodeid); > -out: > - return objp; > -} > -#else > - > -static __always_inline void * > -__do_cache_alloc(struct kmem_cache *cachep, gfp_t flags, int nodeid __maybe_unused) > -{ > - return ____cache_alloc(cachep, flags); > -} > - > -#endif /* CONFIG_NUMA */ > - > -static __always_inline void * > -slab_alloc_node(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags, > - int nodeid, size_t orig_size, unsigned long caller) > -{ > - unsigned long save_flags; > - void *objp; > - struct obj_cgroup *objcg = NULL; > - bool init = false; > - > - flags &= gfp_allowed_mask; > - cachep = slab_pre_alloc_hook(cachep, lru, &objcg, 1, flags); > - if (unlikely(!cachep)) > - return NULL; > - > - objp = kfence_alloc(cachep, orig_size, flags); > - if (unlikely(objp)) > - goto out; > - > - local_irq_save(save_flags); > - objp = __do_cache_alloc(cachep, flags, nodeid); > - local_irq_restore(save_flags); > - objp = cache_alloc_debugcheck_after(cachep, flags, objp, caller); > - prefetchw(objp); > - init = slab_want_init_on_alloc(flags, cachep); > - > -out: > - slab_post_alloc_hook(cachep, objcg, flags, 1, &objp, init, > - cachep->object_size); > - return objp; > -} > - > -static __always_inline void * > -slab_alloc(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags, > - size_t orig_size, unsigned long caller) > -{ > - return slab_alloc_node(cachep, lru, flags, NUMA_NO_NODE, orig_size, > - caller); > -} > - > -/* > - * Caller needs to acquire correct kmem_cache_node's list_lock > - * @list: List of detached free slabs should be freed by caller > - */ > -static void free_block(struct kmem_cache *cachep, void **objpp, > - int nr_objects, int node, struct list_head *list) > -{ > - int i; > - struct kmem_cache_node *n = get_node(cachep, node); > - struct slab *slab; > - > - n->free_objects += nr_objects; > - > - for (i = 0; i < nr_objects; i++) { > - void *objp; > - struct slab *slab; > - > - objp = objpp[i]; > - > - slab = virt_to_slab(objp); > - list_del(&slab->slab_list); > - check_spinlock_acquired_node(cachep, node); > - slab_put_obj(cachep, slab, objp); > - STATS_DEC_ACTIVE(cachep); > - > - /* fixup slab chains */ > - if (slab->active == 0) { > - list_add(&slab->slab_list, &n->slabs_free); > - n->free_slabs++; > - } else { > - /* Unconditionally move a slab to the end of the > - * partial list on free - maximum time for the > - * other objects to be freed, too. > - */ > - list_add_tail(&slab->slab_list, &n->slabs_partial); > - } > - } > - > - while (n->free_objects > n->free_limit && !list_empty(&n->slabs_free)) { > - n->free_objects -= cachep->num; > - > - slab = list_last_entry(&n->slabs_free, struct slab, slab_list); > - list_move(&slab->slab_list, list); > - n->free_slabs--; > - n->total_slabs--; > - } > -} > - > -static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) > -{ > - int batchcount; > - struct kmem_cache_node *n; > - int node = numa_mem_id(); > - LIST_HEAD(list); > - > - batchcount = ac->batchcount; > - > - check_irq_off(); > - n = get_node(cachep, node); > - raw_spin_lock(&n->list_lock); > - if (n->shared) { > - struct array_cache *shared_array = n->shared; > - int max = shared_array->limit - shared_array->avail; > - if (max) { > - if (batchcount > max) > - batchcount = max; > - memcpy(&(shared_array->entry[shared_array->avail]), > - ac->entry, sizeof(void *) * batchcount); > - shared_array->avail += batchcount; > - goto free_done; > - } > - } > - > - free_block(cachep, ac->entry, batchcount, node, &list); > -free_done: > -#if STATS > - { > - int i = 0; > - struct slab *slab; > - > - list_for_each_entry(slab, &n->slabs_free, slab_list) { > - BUG_ON(slab->active); > - > - i++; > - } > - STATS_SET_FREEABLE(cachep, i); > - } > -#endif > - raw_spin_unlock(&n->list_lock); > - ac->avail -= batchcount; > - memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail); > - slabs_destroy(cachep, &list); > -} > - > -/* > - * Release an obj back to its cache. If the obj has a constructed state, it must > - * be in this state _before_ it is released. Called with disabled ints. > - */ > -static __always_inline void __cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - bool init; > - > - memcg_slab_free_hook(cachep, virt_to_slab(objp), &objp, 1); > - > - if (is_kfence_address(objp)) { > - kmemleak_free_recursive(objp, cachep->flags); > - __kfence_free(objp); > - return; > - } > - > - /* > - * As memory initialization might be integrated into KASAN, > - * kasan_slab_free and initialization memset must be > - * kept together to avoid discrepancies in behavior. > - */ > - init = slab_want_init_on_free(cachep); > - if (init && !kasan_has_integrated_init()) > - memset(objp, 0, cachep->object_size); > - /* KASAN might put objp into memory quarantine, delaying its reuse. */ > - if (kasan_slab_free(cachep, objp, init)) > - return; > - > - /* Use KCSAN to help debug racy use-after-free. */ > - if (!(cachep->flags & SLAB_TYPESAFE_BY_RCU)) > - __kcsan_check_access(objp, cachep->object_size, > - KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ASSERT); > - > - ___cache_free(cachep, objp, caller); > -} > - > -void ___cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - struct array_cache *ac = cpu_cache_get(cachep); > - > - check_irq_off(); > - kmemleak_free_recursive(objp, cachep->flags); > - objp = cache_free_debugcheck(cachep, objp, caller); > - > - /* > - * Skip calling cache_free_alien() when the platform is not numa. > - * This will avoid cache misses that happen while accessing slabp (which > - * is per page memory reference) to get nodeid. Instead use a global > - * variable to skip the call, which is mostly likely to be present in > - * the cache. > - */ > - if (nr_online_nodes > 1 && cache_free_alien(cachep, objp)) > - return; > - > - if (ac->avail < ac->limit) { > - STATS_INC_FREEHIT(cachep); > - } else { > - STATS_INC_FREEMISS(cachep); > - cache_flusharray(cachep, ac); > - } > - > - if (sk_memalloc_socks()) { > - struct slab *slab = virt_to_slab(objp); > - > - if (unlikely(slab_test_pfmemalloc(slab))) { > - cache_free_pfmemalloc(cachep, slab, objp); > - return; > - } > - } > - > - __free_one(ac, objp); > -} > - > -static __always_inline > -void *__kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, > - gfp_t flags) > -{ > - void *ret = slab_alloc(cachep, lru, flags, cachep->object_size, _RET_IP_); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, cachep, flags, NUMA_NO_NODE); > - > - return ret; > -} > - > -void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - return __kmem_cache_alloc_lru(cachep, NULL, flags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc); > - > -void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, > - gfp_t flags) > -{ > - return __kmem_cache_alloc_lru(cachep, lru, flags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_lru); > - > -static __always_inline void > -cache_alloc_debugcheck_after_bulk(struct kmem_cache *s, gfp_t flags, > - size_t size, void **p, unsigned long caller) > -{ > - size_t i; > - > - for (i = 0; i < size; i++) > - p[i] = cache_alloc_debugcheck_after(s, flags, p[i], caller); > -} > - > -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, > - void **p) > -{ > - struct obj_cgroup *objcg = NULL; > - unsigned long irqflags; > - size_t i; > - > - s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); > - if (!s) > - return 0; > - > - local_irq_save(irqflags); > - for (i = 0; i < size; i++) { > - void *objp = kfence_alloc(s, s->object_size, flags) ?: > - __do_cache_alloc(s, flags, NUMA_NO_NODE); > - > - if (unlikely(!objp)) > - goto error; > - p[i] = objp; > - } > - local_irq_restore(irqflags); > - > - cache_alloc_debugcheck_after_bulk(s, flags, size, p, _RET_IP_); > - > - /* > - * memcg and kmem_cache debug support and memory initialization. > - * Done outside of the IRQ disabled section. > - */ > - slab_post_alloc_hook(s, objcg, flags, size, p, > - slab_want_init_on_alloc(flags, s), s->object_size); > - /* FIXME: Trace call missing. Christoph would like a bulk variant */ > - return size; > -error: > - local_irq_restore(irqflags); > - cache_alloc_debugcheck_after_bulk(s, flags, i, p, _RET_IP_); > - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); > - kmem_cache_free_bulk(s, i, p); > - return 0; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_bulk); > - > -/** > - * kmem_cache_alloc_node - Allocate an object on the specified node > - * @cachep: The cache to allocate from. > - * @flags: See kmalloc(). > - * @nodeid: node number of the target node. > - * > - * Identical to kmem_cache_alloc but it will allocate memory on the given > - * node, which can improve the performance for cpu bound structures. > - * > - * Fallback to other node is possible if __GFP_THISNODE is not set. > - * > - * Return: pointer to the new object or %NULL in case of error > - */ > -void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) > -{ > - void *ret = slab_alloc_node(cachep, NULL, flags, nodeid, cachep->object_size, _RET_IP_); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, cachep, flags, nodeid); > - > - return ret; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_node); > - > -void *__kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, > - int nodeid, size_t orig_size, > - unsigned long caller) > -{ > - return slab_alloc_node(cachep, NULL, flags, nodeid, > - orig_size, caller); > -} > - > -#ifdef CONFIG_PRINTK > -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) > -{ > - struct kmem_cache *cachep; > - unsigned int objnr; > - void *objp; > - > - kpp->kp_ptr = object; > - kpp->kp_slab = slab; > - cachep = slab->slab_cache; > - kpp->kp_slab_cache = cachep; > - objp = object - obj_offset(cachep); > - kpp->kp_data_offset = obj_offset(cachep); > - slab = virt_to_slab(objp); > - objnr = obj_to_index(cachep, slab, objp); > - objp = index_to_obj(cachep, slab, objnr); > - kpp->kp_objp = objp; > - if (DEBUG && cachep->flags & SLAB_STORE_USER) > - kpp->kp_ret = *dbg_userword(cachep, objp); > -} > -#endif > - > -static __always_inline > -void __do_kmem_cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - unsigned long flags; > - > - local_irq_save(flags); > - debug_check_no_locks_freed(objp, cachep->object_size); > - if (!(cachep->flags & SLAB_DEBUG_OBJECTS)) > - debug_check_no_obj_freed(objp, cachep->object_size); > - __cache_free(cachep, objp, caller); > - local_irq_restore(flags); > -} > - > -void __kmem_cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - __do_kmem_cache_free(cachep, objp, caller); > -} > - > -/** > - * kmem_cache_free - Deallocate an object > - * @cachep: The cache the allocation was from. > - * @objp: The previously allocated object. > - * > - * Free an object which was previously allocated from this > - * cache. > - */ > -void kmem_cache_free(struct kmem_cache *cachep, void *objp) > -{ > - cachep = cache_from_obj(cachep, objp); > - if (!cachep) > - return; > - > - trace_kmem_cache_free(_RET_IP_, objp, cachep); > - __do_kmem_cache_free(cachep, objp, _RET_IP_); > -} > -EXPORT_SYMBOL(kmem_cache_free); > - > -void kmem_cache_free_bulk(struct kmem_cache *orig_s, size_t size, void **p) > -{ > - unsigned long flags; > - > - local_irq_save(flags); > - for (int i = 0; i < size; i++) { > - void *objp = p[i]; > - struct kmem_cache *s; > - > - if (!orig_s) { > - struct folio *folio = virt_to_folio(objp); > - > - /* called via kfree_bulk */ > - if (!folio_test_slab(folio)) { > - local_irq_restore(flags); > - free_large_kmalloc(folio, objp); > - local_irq_save(flags); > - continue; > - } > - s = folio_slab(folio)->slab_cache; > - } else { > - s = cache_from_obj(orig_s, objp); > - } > - > - if (!s) > - continue; > - > - debug_check_no_locks_freed(objp, s->object_size); > - if (!(s->flags & SLAB_DEBUG_OBJECTS)) > - debug_check_no_obj_freed(objp, s->object_size); > - > - __cache_free(s, objp, _RET_IP_); > - } > - local_irq_restore(flags); > - > - /* FIXME: add tracing */ > -} > -EXPORT_SYMBOL(kmem_cache_free_bulk); > - > -/* > - * This initializes kmem_cache_node or resizes various caches for all nodes. > - */ > -static int setup_kmem_cache_nodes(struct kmem_cache *cachep, gfp_t gfp) > -{ > - int ret; > - int node; > - struct kmem_cache_node *n; > - > - for_each_online_node(node) { > - ret = setup_kmem_cache_node(cachep, node, gfp, true); > - if (ret) > - goto fail; > - > - } > - > - return 0; > - > -fail: > - if (!cachep->list.next) { > - /* Cache is not active yet. Roll back what we did */ > - node--; > - while (node >= 0) { > - n = get_node(cachep, node); > - if (n) { > - kfree(n->shared); > - free_alien_cache(n->alien); > - kfree(n); > - cachep->node[node] = NULL; > - } > - node--; > - } > - } > - return -ENOMEM; > -} > - > -/* Always called with the slab_mutex held */ > -static int do_tune_cpucache(struct kmem_cache *cachep, int limit, > - int batchcount, int shared, gfp_t gfp) > -{ > - struct array_cache __percpu *cpu_cache, *prev; > - int cpu; > - > - cpu_cache = alloc_kmem_cache_cpus(cachep, limit, batchcount); > - if (!cpu_cache) > - return -ENOMEM; > - > - prev = cachep->cpu_cache; > - cachep->cpu_cache = cpu_cache; > - /* > - * Without a previous cpu_cache there's no need to synchronize remote > - * cpus, so skip the IPIs. > - */ > - if (prev) > - kick_all_cpus_sync(); > - > - check_irq_on(); > - cachep->batchcount = batchcount; > - cachep->limit = limit; > - cachep->shared = shared; > - > - if (!prev) > - goto setup_node; > - > - for_each_online_cpu(cpu) { > - LIST_HEAD(list); > - int node; > - struct kmem_cache_node *n; > - struct array_cache *ac = per_cpu_ptr(prev, cpu); > - > - node = cpu_to_mem(cpu); > - n = get_node(cachep, node); > - raw_spin_lock_irq(&n->list_lock); > - free_block(cachep, ac->entry, ac->avail, node, &list); > - raw_spin_unlock_irq(&n->list_lock); > - slabs_destroy(cachep, &list); > - } > - free_percpu(prev); > - > -setup_node: > - return setup_kmem_cache_nodes(cachep, gfp); > -} > - > -/* Called with slab_mutex held always */ > -static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp) > -{ > - int err; > - int limit = 0; > - int shared = 0; > - int batchcount = 0; > - > - err = cache_random_seq_create(cachep, cachep->num, gfp); > - if (err) > - goto end; > - > - /* > - * The head array serves three purposes: > - * - create a LIFO ordering, i.e. return objects that are cache-warm > - * - reduce the number of spinlock operations. > - * - reduce the number of linked list operations on the slab and > - * bufctl chains: array operations are cheaper. > - * The numbers are guessed, we should auto-tune as described by > - * Bonwick. > - */ > - if (cachep->size > 131072) > - limit = 1; > - else if (cachep->size > PAGE_SIZE) > - limit = 8; > - else if (cachep->size > 1024) > - limit = 24; > - else if (cachep->size > 256) > - limit = 54; > - else > - limit = 120; > - > - /* > - * CPU bound tasks (e.g. network routing) can exhibit cpu bound > - * allocation behaviour: Most allocs on one cpu, most free operations > - * on another cpu. For these cases, an efficient object passing between > - * cpus is necessary. This is provided by a shared array. The array > - * replaces Bonwick's magazine layer. > - * On uniprocessor, it's functionally equivalent (but less efficient) > - * to a larger limit. Thus disabled by default. > - */ > - shared = 0; > - if (cachep->size <= PAGE_SIZE && num_possible_cpus() > 1) > - shared = 8; > - > -#if DEBUG > - /* > - * With debugging enabled, large batchcount lead to excessively long > - * periods with disabled local interrupts. Limit the batchcount > - */ > - if (limit > 32) > - limit = 32; > -#endif > - batchcount = (limit + 1) / 2; > - err = do_tune_cpucache(cachep, limit, batchcount, shared, gfp); > -end: > - if (err) > - pr_err("enable_cpucache failed for %s, error %d\n", > - cachep->name, -err); > - return err; > -} > - > -/* > - * Drain an array if it contains any elements taking the node lock only if > - * necessary. Note that the node listlock also protects the array_cache > - * if drain_array() is used on the shared array. > - */ > -static void drain_array(struct kmem_cache *cachep, struct kmem_cache_node *n, > - struct array_cache *ac, int node) > -{ > - LIST_HEAD(list); > - > - /* ac from n->shared can be freed if we don't hold the slab_mutex. */ > - check_mutex_acquired(); > - > - if (!ac || !ac->avail) > - return; > - > - if (ac->touched) { > - ac->touched = 0; > - return; > - } > - > - raw_spin_lock_irq(&n->list_lock); > - drain_array_locked(cachep, ac, node, false, &list); > - raw_spin_unlock_irq(&n->list_lock); > - > - slabs_destroy(cachep, &list); > -} > - > -/** > - * cache_reap - Reclaim memory from caches. > - * @w: work descriptor > - * > - * Called from workqueue/eventd every few seconds. > - * Purpose: > - * - clear the per-cpu caches for this CPU. > - * - return freeable pages to the main free memory pool. > - * > - * If we cannot acquire the cache chain mutex then just give up - we'll try > - * again on the next iteration. > - */ > -static void cache_reap(struct work_struct *w) > -{ > - struct kmem_cache *searchp; > - struct kmem_cache_node *n; > - int node = numa_mem_id(); > - struct delayed_work *work = to_delayed_work(w); > - > - if (!mutex_trylock(&slab_mutex)) > - /* Give up. Setup the next iteration. */ > - goto out; > - > - list_for_each_entry(searchp, &slab_caches, list) { > - check_irq_on(); > - > - /* > - * We only take the node lock if absolutely necessary and we > - * have established with reasonable certainty that > - * we can do some work if the lock was obtained. > - */ > - n = get_node(searchp, node); > - > - reap_alien(searchp, n); > - > - drain_array(searchp, n, cpu_cache_get(searchp), node); > - > - /* > - * These are racy checks but it does not matter > - * if we skip one check or scan twice. > - */ > - if (time_after(n->next_reap, jiffies)) > - goto next; > - > - n->next_reap = jiffies + REAPTIMEOUT_NODE; > - > - drain_array(searchp, n, n->shared, node); > - > - if (n->free_touched) > - n->free_touched = 0; > - else { > - int freed; > - > - freed = drain_freelist(searchp, n, (n->free_limit + > - 5 * searchp->num - 1) / (5 * searchp->num)); > - STATS_ADD_REAPED(searchp, freed); > - } > -next: > - cond_resched(); > - } > - check_irq_on(); > - mutex_unlock(&slab_mutex); > - next_reap_node(); > -out: > - /* Set up the next iteration */ > - schedule_delayed_work_on(smp_processor_id(), work, > - round_jiffies_relative(REAPTIMEOUT_AC)); > -} > - > -void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo) > -{ > - unsigned long active_objs, num_objs, active_slabs; > - unsigned long total_slabs = 0, free_objs = 0, shared_avail = 0; > - unsigned long free_slabs = 0; > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(cachep, node, n) { > - check_irq_on(); > - raw_spin_lock_irq(&n->list_lock); > - > - total_slabs += n->total_slabs; > - free_slabs += n->free_slabs; > - free_objs += n->free_objects; > - > - if (n->shared) > - shared_avail += n->shared->avail; > - > - raw_spin_unlock_irq(&n->list_lock); > - } > - num_objs = total_slabs * cachep->num; > - active_slabs = total_slabs - free_slabs; > - active_objs = num_objs - free_objs; > - > - sinfo->active_objs = active_objs; > - sinfo->num_objs = num_objs; > - sinfo->active_slabs = active_slabs; > - sinfo->num_slabs = total_slabs; > - sinfo->shared_avail = shared_avail; > - sinfo->limit = cachep->limit; > - sinfo->batchcount = cachep->batchcount; > - sinfo->shared = cachep->shared; > - sinfo->objects_per_slab = cachep->num; > - sinfo->cache_order = cachep->gfporder; > -} > - > -void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *cachep) > -{ > -#if STATS > - { /* node stats */ > - unsigned long high = cachep->high_mark; > - unsigned long allocs = cachep->num_allocations; > - unsigned long grown = cachep->grown; > - unsigned long reaped = cachep->reaped; > - unsigned long errors = cachep->errors; > - unsigned long max_freeable = cachep->max_freeable; > - unsigned long node_allocs = cachep->node_allocs; > - unsigned long node_frees = cachep->node_frees; > - unsigned long overflows = cachep->node_overflow; > - > - seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu %4lu %4lu %4lu %4lu %4lu", > - allocs, high, grown, > - reaped, errors, max_freeable, node_allocs, > - node_frees, overflows); > - } > - /* cpu stats */ > - { > - unsigned long allochit = atomic_read(&cachep->allochit); > - unsigned long allocmiss = atomic_read(&cachep->allocmiss); > - unsigned long freehit = atomic_read(&cachep->freehit); > - unsigned long freemiss = atomic_read(&cachep->freemiss); > - > - seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu", > - allochit, allocmiss, freehit, freemiss); > - } > -#endif > -} > - > -#define MAX_SLABINFO_WRITE 128 > -/** > - * slabinfo_write - Tuning for the slab allocator > - * @file: unused > - * @buffer: user buffer > - * @count: data length > - * @ppos: unused > - * > - * Return: %0 on success, negative error code otherwise. > - */ > -ssize_t slabinfo_write(struct file *file, const char __user *buffer, > - size_t count, loff_t *ppos) > -{ > - char kbuf[MAX_SLABINFO_WRITE + 1], *tmp; > - int limit, batchcount, shared, res; > - struct kmem_cache *cachep; > - > - if (count > MAX_SLABINFO_WRITE) > - return -EINVAL; > - if (copy_from_user(&kbuf, buffer, count)) > - return -EFAULT; > - kbuf[MAX_SLABINFO_WRITE] = '\0'; > - > - tmp = strchr(kbuf, ' '); > - if (!tmp) > - return -EINVAL; > - *tmp = '\0'; > - tmp++; > - if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3) > - return -EINVAL; > - > - /* Find the cache in the chain of caches. */ > - mutex_lock(&slab_mutex); > - res = -EINVAL; > - list_for_each_entry(cachep, &slab_caches, list) { > - if (!strcmp(cachep->name, kbuf)) { > - if (limit < 1 || batchcount < 1 || > - batchcount > limit || shared < 0) { > - res = 0; > - } else { > - res = do_tune_cpucache(cachep, limit, > - batchcount, shared, > - GFP_KERNEL); > - } > - break; > - } > - } > - mutex_unlock(&slab_mutex); > - if (res >= 0) > - res = count; > - return res; > -} > - > -#ifdef CONFIG_HARDENED_USERCOPY > -/* > - * Rejects incorrectly sized objects and objects that are to be copied > - * to/from userspace but do not fall entirely within the containing slab > - * cache's usercopy region. > - * > - * Returns NULL if check passes, otherwise const char * to name of cache > - * to indicate an error. > - */ > -void __check_heap_object(const void *ptr, unsigned long n, > - const struct slab *slab, bool to_user) > -{ > - struct kmem_cache *cachep; > - unsigned int objnr; > - unsigned long offset; > - > - ptr = kasan_reset_tag(ptr); > - > - /* Find and validate object. */ > - cachep = slab->slab_cache; > - objnr = obj_to_index(cachep, slab, (void *)ptr); > - BUG_ON(objnr >= cachep->num); > - > - /* Find offset within object. */ > - if (is_kfence_address(ptr)) > - offset = ptr - kfence_object_start(ptr); > - else > - offset = ptr - index_to_obj(cachep, slab, objnr) - obj_offset(cachep); > - > - /* Allow address range falling entirely within usercopy region. */ > - if (offset >= cachep->useroffset && > - offset - cachep->useroffset <= cachep->usersize && > - n <= cachep->useroffset - offset + cachep->usersize) > - return; > - > - usercopy_abort("SLAB object", cachep->name, to_user, offset, n); > -} > -#endif /* CONFIG_HARDENED_USERCOPY */ > diff --git a/mm/slab.h b/mm/slab.h > index 43966aa5fadf..53e97b7640e9 100644 > --- a/mm/slab.h > +++ b/mm/slab.h > @@ -9,60 +9,12 @@ > struct slab { > unsigned long __page_flags; > > -#if defined(CONFIG_SLAB) > - > - struct kmem_cache *slab_cache; > - union { > - struct { > - struct list_head slab_list; > - void *freelist; /* array of free object indexes */ > - void *s_mem; /* first object */ > - }; > - struct rcu_head rcu_head; > - }; > - unsigned int active; > - > -#elif defined(CONFIG_SLUB) > - > - struct kmem_cache *slab_cache; > - union { > - struct { > - union { > - struct list_head slab_list; > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - struct { > - struct slab *next; > - int slabs; /* Nr of slabs left */ > - }; > -#endif > - }; > - /* Double-word boundary */ > - void *freelist; /* first free object */ > - union { > - unsigned long counters; > - struct { > - unsigned inuse:16; > - unsigned objects:15; > - unsigned frozen:1; > - }; > - }; > - }; > - struct rcu_head rcu_head; > - }; > - unsigned int __unused; > - > -#elif defined(CONFIG_SLOB) > - > struct list_head slab_list; > void *__unused_1; > void *freelist; /* first free block */ > long units; > unsigned int __unused_2; > > -#else > -#error "Unexpected slab allocator configured" > -#endif > - > atomic_t __page_refcount; > #ifdef CONFIG_MEMCG > unsigned long memcg_data; > @@ -72,20 +24,13 @@ struct slab { > #define SLAB_MATCH(pg, sl) \ > static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl)) > SLAB_MATCH(flags, __page_flags); > -#ifndef CONFIG_SLOB > -SLAB_MATCH(compound_head, slab_cache); /* Ensure bit 0 is clear */ > -#else > SLAB_MATCH(compound_head, slab_list); /* Ensure bit 0 is clear */ > -#endif > SLAB_MATCH(_refcount, __page_refcount); > #ifdef CONFIG_MEMCG > SLAB_MATCH(memcg_data, memcg_data); > #endif > #undef SLAB_MATCH > static_assert(sizeof(struct slab) <= sizeof(struct page)); > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && defined(CONFIG_SLUB) > -static_assert(IS_ALIGNED(offsetof(struct slab, freelist), 2*sizeof(void *))); > -#endif > > /** > * folio_slab - Converts from folio to slab. > @@ -200,7 +145,6 @@ static inline size_t slab_size(const struct slab *slab) > return PAGE_SIZE << slab_order(slab); > } > > -#ifdef CONFIG_SLOB > /* > * Common fields provided in kmem_cache by all slab allocators > * This struct is either used directly by the allocator (SLOB) > @@ -223,16 +167,6 @@ struct kmem_cache { > struct list_head list; /* List of all slab caches on the system */ > }; > > -#endif /* CONFIG_SLOB */ > - > -#ifdef CONFIG_SLAB > -#include <linux/slab_def.h> > -#endif > - > -#ifdef CONFIG_SLUB > -#include <linux/slub_def.h> > -#endif > - > #include <linux/memcontrol.h> > #include <linux/fault-inject.h> > #include <linux/kasan.h> > @@ -268,26 +202,6 @@ extern struct list_head slab_caches; > /* The slab cache that manages slab cache information */ > extern struct kmem_cache *kmem_cache; > > -/* A table of kmalloc cache names and sizes */ > -extern const struct kmalloc_info_struct { > - const char *name[NR_KMALLOC_TYPES]; > - unsigned int size; > -} kmalloc_info[]; > - > -#ifndef CONFIG_SLOB > -/* Kmalloc array related functions */ > -void setup_kmalloc_cache_index_table(void); > -void create_kmalloc_caches(slab_flags_t); > - > -/* Find the kmalloc slab corresponding for a certain size */ > -struct kmem_cache *kmalloc_slab(size_t, gfp_t); > - > -void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, > - int node, size_t orig_size, > - unsigned long caller); > -void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller); > -#endif > - > gfp_t kmalloc_fix_flags(gfp_t flags); > > /* Functions provided by the slab allocators */ > @@ -303,14 +217,6 @@ extern void create_boot_cache(struct kmem_cache *, const char *name, > int slab_unmergeable(struct kmem_cache *s); > struct kmem_cache *find_mergeable(unsigned size, unsigned align, > slab_flags_t flags, const char *name, void (*ctor)(void *)); > -#ifndef CONFIG_SLOB > -struct kmem_cache * > -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > - slab_flags_t flags, void (*ctor)(void *)); > - > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name); > -#else > static inline struct kmem_cache * > __kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > slab_flags_t flags, void (*ctor)(void *)) > @@ -321,15 +227,10 @@ static inline slab_flags_t kmem_cache_flags(unsigned int object_size, > { > return flags; > } > -#endif > > static inline bool is_kmalloc_cache(struct kmem_cache *s) > { > -#ifndef CONFIG_SLOB > - return (s->flags & SLAB_KMALLOC); > -#else > return false; > -#endif > } > > /* Legal flag mask for kmem_cache_create(), for various configurations */ > @@ -337,26 +238,9 @@ static inline bool is_kmalloc_cache(struct kmem_cache *s) > SLAB_CACHE_DMA32 | SLAB_PANIC | \ > SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS ) > > -#if defined(CONFIG_DEBUG_SLAB) > -#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) > -#elif defined(CONFIG_SLUB_DEBUG) > -#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ > - SLAB_TRACE | SLAB_CONSISTENCY_CHECKS) > -#else > #define SLAB_DEBUG_FLAGS (0) > -#endif > > -#if defined(CONFIG_SLAB) > -#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \ > - SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \ > - SLAB_ACCOUNT) > -#elif defined(CONFIG_SLUB) > -#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ > - SLAB_TEMPORARY | SLAB_ACCOUNT | \ > - SLAB_NO_USER_FLAGS | SLAB_KMALLOC) > -#else > #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE) > -#endif > > /* Common flags available with current configuration */ > #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS) > @@ -409,19 +293,6 @@ static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s) > NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B; > } > > -#ifdef CONFIG_SLUB_DEBUG > -#ifdef CONFIG_SLUB_DEBUG_ON > -DECLARE_STATIC_KEY_TRUE(slub_debug_enabled); > -#else > -DECLARE_STATIC_KEY_FALSE(slub_debug_enabled); > -#endif > -extern void print_tracking(struct kmem_cache *s, void *object); > -long validate_slab_cache(struct kmem_cache *s); > -static inline bool __slub_debug_enabled(void) > -{ > - return static_branch_unlikely(&slub_debug_enabled); > -} > -#else > static inline void print_tracking(struct kmem_cache *s, void *object) > { > } > @@ -429,7 +300,6 @@ static inline bool __slub_debug_enabled(void) > { > return false; > } > -#endif > > /* > * Returns true if any of the specified slub_debug flags is enabled for the > @@ -438,160 +308,9 @@ static inline bool __slub_debug_enabled(void) > */ > static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags) > { > - if (IS_ENABLED(CONFIG_SLUB_DEBUG)) > - VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS)); > - if (__slub_debug_enabled()) > - return s->flags & flags; > return false; > } > > -#ifdef CONFIG_MEMCG_KMEM > -/* > - * slab_objcgs - get the object cgroups vector associated with a slab > - * @slab: a pointer to the slab struct > - * > - * Returns a pointer to the object cgroups vector associated with the slab, > - * or NULL if no such vector has been associated yet. > - */ > -static inline struct obj_cgroup **slab_objcgs(struct slab *slab) > -{ > - unsigned long memcg_data = READ_ONCE(slab->memcg_data); > - > - VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), > - slab_page(slab)); > - VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, slab_page(slab)); > - > - return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); > -} > - > -int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s, > - gfp_t gfp, bool new_slab); > -void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, > - enum node_stat_item idx, int nr); > - > -static inline void memcg_free_slab_cgroups(struct slab *slab) > -{ > - kfree(slab_objcgs(slab)); > - slab->memcg_data = 0; > -} > - > -static inline size_t obj_full_size(struct kmem_cache *s) > -{ > - /* > - * For each accounted object there is an extra space which is used > - * to store obj_cgroup membership. Charge it too. > - */ > - return s->size + sizeof(struct obj_cgroup *); > -} > - > -/* > - * Returns false if the allocation should fail. > - */ > -static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, > - struct list_lru *lru, > - struct obj_cgroup **objcgp, > - size_t objects, gfp_t flags) > -{ > - struct obj_cgroup *objcg; > - > - if (!memcg_kmem_online()) > - return true; > - > - if (!(flags & __GFP_ACCOUNT) && !(s->flags & SLAB_ACCOUNT)) > - return true; > - > - objcg = get_obj_cgroup_from_current(); > - if (!objcg) > - return true; > - > - if (lru) { > - int ret; > - struct mem_cgroup *memcg; > - > - memcg = get_mem_cgroup_from_objcg(objcg); > - ret = memcg_list_lru_alloc(memcg, lru, flags); > - css_put(&memcg->css); > - > - if (ret) > - goto out; > - } > - > - if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s))) > - goto out; > - > - *objcgp = objcg; > - return true; > -out: > - obj_cgroup_put(objcg); > - return false; > -} > - > -static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, > - struct obj_cgroup *objcg, > - gfp_t flags, size_t size, > - void **p) > -{ > - struct slab *slab; > - unsigned long off; > - size_t i; > - > - if (!memcg_kmem_online() || !objcg) > - return; > - > - for (i = 0; i < size; i++) { > - if (likely(p[i])) { > - slab = virt_to_slab(p[i]); > - > - if (!slab_objcgs(slab) && > - memcg_alloc_slab_cgroups(slab, s, flags, > - false)) { > - obj_cgroup_uncharge(objcg, obj_full_size(s)); > - continue; > - } > - > - off = obj_to_index(s, slab, p[i]); > - obj_cgroup_get(objcg); > - slab_objcgs(slab)[off] = objcg; > - mod_objcg_state(objcg, slab_pgdat(slab), > - cache_vmstat_idx(s), obj_full_size(s)); > - } else { > - obj_cgroup_uncharge(objcg, obj_full_size(s)); > - } > - } > - obj_cgroup_put(objcg); > -} > - > -static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, > - void **p, int objects) > -{ > - struct obj_cgroup **objcgs; > - int i; > - > - if (!memcg_kmem_online()) > - return; > - > - objcgs = slab_objcgs(slab); > - if (!objcgs) > - return; > - > - for (i = 0; i < objects; i++) { > - struct obj_cgroup *objcg; > - unsigned int off; > - > - off = obj_to_index(s, slab, p[i]); > - objcg = objcgs[off]; > - if (!objcg) > - continue; > - > - objcgs[off] = NULL; > - obj_cgroup_uncharge(objcg, obj_full_size(s)); > - mod_objcg_state(objcg, slab_pgdat(slab), cache_vmstat_idx(s), > - -obj_full_size(s)); > - obj_cgroup_put(objcg); > - } > -} > - > -#else /* CONFIG_MEMCG_KMEM */ > static inline struct obj_cgroup **slab_objcgs(struct slab *slab) > { > return NULL; > @@ -632,90 +351,12 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, > void **p, int objects) > { > } > -#endif /* CONFIG_MEMCG_KMEM */ > - > -#ifndef CONFIG_SLOB > -static inline struct kmem_cache *virt_to_cache(const void *obj) > -{ > - struct slab *slab; > - > - slab = virt_to_slab(obj); > - if (WARN_ONCE(!slab, "%s: Object is not a Slab page!\n", > - __func__)) > - return NULL; > - return slab->slab_cache; > -} > - > -static __always_inline void account_slab(struct slab *slab, int order, > - struct kmem_cache *s, gfp_t gfp) > -{ > - if (memcg_kmem_online() && (s->flags & SLAB_ACCOUNT)) > - memcg_alloc_slab_cgroups(slab, s, gfp, true); > - > - mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), > - PAGE_SIZE << order); > -} > - > -static __always_inline void unaccount_slab(struct slab *slab, int order, > - struct kmem_cache *s) > -{ > - if (memcg_kmem_online()) > - memcg_free_slab_cgroups(slab); > - > - mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), > - -(PAGE_SIZE << order)); > -} > - > -static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) > -{ > - struct kmem_cache *cachep; > - > - if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && > - !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) > - return s; > - > - cachep = virt_to_cache(x); > - if (WARN(cachep && cachep != s, > - "%s: Wrong slab cache. %s but object is from %s\n", > - __func__, s->name, cachep->name)) > - print_tracking(cachep, x); > - return cachep; > -} > - > -void free_large_kmalloc(struct folio *folio, void *object); > - > -#endif /* CONFIG_SLOB */ > > size_t __ksize(const void *objp); > > static inline size_t slab_ksize(const struct kmem_cache *s) > { > -#ifndef CONFIG_SLUB > return s->object_size; > - > -#else /* CONFIG_SLUB */ > -# ifdef CONFIG_SLUB_DEBUG > - /* > - * Debugging requires use of the padding between object > - * and whatever may come after it. > - */ > - if (s->flags & (SLAB_RED_ZONE | SLAB_POISON)) > - return s->object_size; > -# endif > - if (s->flags & SLAB_KASAN) > - return s->object_size; > - /* > - * If we have the need to store the freelist pointer > - * back there or track user information then we can > - * only use the space before that information. > - */ > - if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER)) > - return s->inuse; > - /* > - * Else we can use all the padding etc for the allocation > - */ > - return s->size; > -#endif > } > > static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, > @@ -777,77 +418,18 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, > memcg_slab_post_alloc_hook(s, objcg, flags, size, p); > } > > -#ifndef CONFIG_SLOB > -/* > - * The slab lists for all objects. > - */ > -struct kmem_cache_node { > -#ifdef CONFIG_SLAB > - raw_spinlock_t list_lock; > - struct list_head slabs_partial; /* partial list first, better asm code */ > - struct list_head slabs_full; > - struct list_head slabs_free; > - unsigned long total_slabs; /* length of all slab lists */ > - unsigned long free_slabs; /* length of free slab list only */ > - unsigned long free_objects; > - unsigned int free_limit; > - unsigned int colour_next; /* Per-node cache coloring */ > - struct array_cache *shared; /* shared per node */ > - struct alien_cache **alien; /* on other nodes */ > - unsigned long next_reap; /* updated without locking */ > - int free_touched; /* updated without locking */ > -#endif > - > -#ifdef CONFIG_SLUB > - spinlock_t list_lock; > - unsigned long nr_partial; > - struct list_head partial; > -#ifdef CONFIG_SLUB_DEBUG > - atomic_long_t nr_slabs; > - atomic_long_t total_objects; > - struct list_head full; > -#endif > -#endif > - > -}; > - > -static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node) > -{ > - return s->node[node]; > -} > - > -/* > - * Iterator over all nodes. The body will be executed for each node that has > - * a kmem_cache_node structure allocated (which is true for all online nodes) > - */ > -#define for_each_kmem_cache_node(__s, __node, __n) \ > - for (__node = 0; __node < nr_node_ids; __node++) \ > - if ((__n = get_node(__s, __node))) > - > -#endif > - > -#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG) > -void dump_unreclaimable_slab(void); > -#else > static inline void dump_unreclaimable_slab(void) > { > } > -#endif > > void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr); > > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, > - gfp_t gfp); > -void cache_random_seq_destroy(struct kmem_cache *cachep); > -#else > static inline int cache_random_seq_create(struct kmem_cache *cachep, > unsigned int count, gfp_t gfp) > { > return 0; > } > static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { } > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > > static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c) > { > @@ -871,11 +453,7 @@ static inline bool slab_want_init_on_free(struct kmem_cache *c) > return false; > } > > -#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) > -void debugfs_slab_release(struct kmem_cache *); > -#else > static inline void debugfs_slab_release(struct kmem_cache *s) { } > -#endif > > #ifdef CONFIG_PRINTK > #define KS_ADDRS_COUNT 16 > @@ -903,8 +481,4 @@ void __check_heap_object(const void *ptr, unsigned long n, > } > #endif > > -#ifdef CONFIG_SLUB_DEBUG > -void skip_orig_size_check(struct kmem_cache *s, const void *object); > -#endif > - > #endif /* MM_SLAB_H */ > diff --git a/mm/slab_common.c b/mm/slab_common.c > index bf4e777cfe90..5f6a59e31abd 100644 > --- a/mm/slab_common.c > +++ b/mm/slab_common.c > @@ -69,11 +69,6 @@ static int __init setup_slab_merge(char *str) > return 1; > } > > -#ifdef CONFIG_SLUB > -__setup_param("slub_nomerge", slub_nomerge, setup_slab_nomerge, 0); > -__setup_param("slub_merge", slub_merge, setup_slab_merge, 0); > -#endif > - > __setup("slab_nomerge", setup_slab_nomerge); > __setup("slab_merge", setup_slab_merge); > > @@ -195,15 +190,29 @@ struct kmem_cache *find_mergeable(unsigned int size, unsigned int align, > if (s->size - size >= sizeof(void *)) > continue; > > - if (IS_ENABLED(CONFIG_SLAB) && align && > - (align > s->align || s->align % align)) > - continue; > - > return s; > } > return NULL; > } > > +struct slab_rcu { > + struct rcu_head head; > + int size; > +}; > + > +int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags) > +{ > + if (flags & SLAB_TYPESAFE_BY_RCU) { > + /* leave room for rcu footer at the end of object */ > + c->size += sizeof(struct slab_rcu); > + } > + > + /* Actual size allocated */ > + c->size = PAGE_SIZE << get_order(c->size); > + c->flags = flags; > + return 0; > +} > + > static struct kmem_cache *create_cache(const char *name, > unsigned int object_size, unsigned int align, > slab_flags_t flags, unsigned int useroffset, > @@ -285,20 +294,6 @@ kmem_cache_create_usercopy(const char *name, > const char *cache_name; > int err; > > -#ifdef CONFIG_SLUB_DEBUG > - /* > - * If no slub_debug was enabled globally, the static key is not yet > - * enabled by setup_slub_debug(). Enable it if the cache is being > - * created with any of the debugging flags passed explicitly. > - * It's also possible that this is the first cache created with > - * SLAB_STORE_USER and we should init stack_depot for it. > - */ > - if (flags & SLAB_DEBUG_FLAGS) > - static_branch_enable(&slub_debug_enabled); > - if (flags & SLAB_STORE_USER) > - stack_depot_init(); > -#endif > - > mutex_lock(&slab_mutex); > > err = kmem_cache_sanity_check(name, size); > @@ -552,7 +547,8 @@ static void kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab * > { > if (__kfence_obj_info(kpp, object, slab)) > return; > - __kmem_obj_info(kpp, object, slab); > + kpp->kp_ptr = object; > + kpp->kp_slab = slab; > } > > /** > @@ -625,462 +621,6 @@ void kmem_dump_obj(void *object) > EXPORT_SYMBOL_GPL(kmem_dump_obj); > #endif > > -#ifndef CONFIG_SLOB > -/* Create a cache during boot when no slab services are available yet */ > -void __init create_boot_cache(struct kmem_cache *s, const char *name, > - unsigned int size, slab_flags_t flags, > - unsigned int useroffset, unsigned int usersize) > -{ > - int err; > - unsigned int align = ARCH_KMALLOC_MINALIGN; > - > - s->name = name; > - s->size = s->object_size = size; > - > - /* > - * For power of two sizes, guarantee natural alignment for kmalloc > - * caches, regardless of SL*B debugging options. > - */ > - if (is_power_of_2(size)) > - align = max(align, size); > - s->align = calculate_alignment(flags, align, size); > - > -#ifdef CONFIG_HARDENED_USERCOPY > - s->useroffset = useroffset; > - s->usersize = usersize; > -#endif > - > - err = __kmem_cache_create(s, flags); > - > - if (err) > - panic("Creation of kmalloc slab %s size=%u failed. Reason %d\n", > - name, size, err); > - > - s->refcount = -1; /* Exempt from merging for now */ > -} > - > -struct kmem_cache *__init create_kmalloc_cache(const char *name, > - unsigned int size, slab_flags_t flags, > - unsigned int useroffset, unsigned int usersize) > -{ > - struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); > - > - if (!s) > - panic("Out of memory when creating slab %s\n", name); > - > - create_boot_cache(s, name, size, flags | SLAB_KMALLOC, useroffset, > - usersize); > - list_add(&s->list, &slab_caches); > - s->refcount = 1; > - return s; > -} > - > -struct kmem_cache * > -kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1] __ro_after_init = > -{ /* initialization for https://bugs.llvm.org/show_bug.cgi?id=42570 */ }; > -EXPORT_SYMBOL(kmalloc_caches); > - > -/* > - * Conversion table for small slabs sizes / 8 to the index in the > - * kmalloc array. This is necessary for slabs < 192 since we have non power > - * of two cache sizes there. The size of larger slabs can be determined using > - * fls. > - */ > -static u8 size_index[24] __ro_after_init = { > - 3, /* 8 */ > - 4, /* 16 */ > - 5, /* 24 */ > - 5, /* 32 */ > - 6, /* 40 */ > - 6, /* 48 */ > - 6, /* 56 */ > - 6, /* 64 */ > - 1, /* 72 */ > - 1, /* 80 */ > - 1, /* 88 */ > - 1, /* 96 */ > - 7, /* 104 */ > - 7, /* 112 */ > - 7, /* 120 */ > - 7, /* 128 */ > - 2, /* 136 */ > - 2, /* 144 */ > - 2, /* 152 */ > - 2, /* 160 */ > - 2, /* 168 */ > - 2, /* 176 */ > - 2, /* 184 */ > - 2 /* 192 */ > -}; > - > -static inline unsigned int size_index_elem(unsigned int bytes) > -{ > - return (bytes - 1) / 8; > -} > - > -/* > - * Find the kmem_cache structure that serves a given size of > - * allocation > - */ > -struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags) > -{ > - unsigned int index; > - > - if (size <= 192) { > - if (!size) > - return ZERO_SIZE_PTR; > - > - index = size_index[size_index_elem(size)]; > - } else { > - if (WARN_ON_ONCE(size > KMALLOC_MAX_CACHE_SIZE)) > - return NULL; > - index = fls(size - 1); > - } > - > - return kmalloc_caches[kmalloc_type(flags)][index]; > -} > - > -size_t kmalloc_size_roundup(size_t size) > -{ > - struct kmem_cache *c; > - > - /* Short-circuit the 0 size case. */ > - if (unlikely(size == 0)) > - return 0; > - /* Short-circuit saturated "too-large" case. */ > - if (unlikely(size == SIZE_MAX)) > - return SIZE_MAX; > - /* Above the smaller buckets, size is a multiple of page size. */ > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return PAGE_SIZE << get_order(size); > - > - /* The flags don't matter since size_index is common to all. */ > - c = kmalloc_slab(size, GFP_KERNEL); > - return c ? c->object_size : 0; > -} > -EXPORT_SYMBOL(kmalloc_size_roundup); > - > -#ifdef CONFIG_ZONE_DMA > -#define KMALLOC_DMA_NAME(sz) .name[KMALLOC_DMA] = "dma-kmalloc-" #sz, > -#else > -#define KMALLOC_DMA_NAME(sz) > -#endif > - > -#ifdef CONFIG_MEMCG_KMEM > -#define KMALLOC_CGROUP_NAME(sz) .name[KMALLOC_CGROUP] = "kmalloc-cg-" #sz, > -#else > -#define KMALLOC_CGROUP_NAME(sz) > -#endif > - > -#ifndef CONFIG_SLUB_TINY > -#define KMALLOC_RCL_NAME(sz) .name[KMALLOC_RECLAIM] = "kmalloc-rcl-" #sz, > -#else > -#define KMALLOC_RCL_NAME(sz) > -#endif > - > -#define INIT_KMALLOC_INFO(__size, __short_size) \ > -{ \ > - .name[KMALLOC_NORMAL] = "kmalloc-" #__short_size, \ > - KMALLOC_RCL_NAME(__short_size) \ > - KMALLOC_CGROUP_NAME(__short_size) \ > - KMALLOC_DMA_NAME(__short_size) \ > - .size = __size, \ > -} > - > -/* > - * kmalloc_info[] is to make slub_debug=,kmalloc-xx option work at boot time. > - * kmalloc_index() supports up to 2^21=2MB, so the final entry of the table is > - * kmalloc-2M. > - */ > -const struct kmalloc_info_struct kmalloc_info[] __initconst = { > - INIT_KMALLOC_INFO(0, 0), > - INIT_KMALLOC_INFO(96, 96), > - INIT_KMALLOC_INFO(192, 192), > - INIT_KMALLOC_INFO(8, 8), > - INIT_KMALLOC_INFO(16, 16), > - INIT_KMALLOC_INFO(32, 32), > - INIT_KMALLOC_INFO(64, 64), > - INIT_KMALLOC_INFO(128, 128), > - INIT_KMALLOC_INFO(256, 256), > - INIT_KMALLOC_INFO(512, 512), > - INIT_KMALLOC_INFO(1024, 1k), > - INIT_KMALLOC_INFO(2048, 2k), > - INIT_KMALLOC_INFO(4096, 4k), > - INIT_KMALLOC_INFO(8192, 8k), > - INIT_KMALLOC_INFO(16384, 16k), > - INIT_KMALLOC_INFO(32768, 32k), > - INIT_KMALLOC_INFO(65536, 64k), > - INIT_KMALLOC_INFO(131072, 128k), > - INIT_KMALLOC_INFO(262144, 256k), > - INIT_KMALLOC_INFO(524288, 512k), > - INIT_KMALLOC_INFO(1048576, 1M), > - INIT_KMALLOC_INFO(2097152, 2M) > -}; > - > -/* > - * Patch up the size_index table if we have strange large alignment > - * requirements for the kmalloc array. This is only the case for > - * MIPS it seems. The standard arches will not generate any code here. > - * > - * Largest permitted alignment is 256 bytes due to the way we > - * handle the index determination for the smaller caches. > - * > - * Make sure that nothing crazy happens if someone starts tinkering > - * around with ARCH_KMALLOC_MINALIGN > - */ > -void __init setup_kmalloc_cache_index_table(void) > -{ > - unsigned int i; > - > - BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 || > - !is_power_of_2(KMALLOC_MIN_SIZE)); > - > - for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) { > - unsigned int elem = size_index_elem(i); > - > - if (elem >= ARRAY_SIZE(size_index)) > - break; > - size_index[elem] = KMALLOC_SHIFT_LOW; > - } > - > - if (KMALLOC_MIN_SIZE >= 64) { > - /* > - * The 96 byte sized cache is not used if the alignment > - * is 64 byte. > - */ > - for (i = 64 + 8; i <= 96; i += 8) > - size_index[size_index_elem(i)] = 7; > - > - } > - > - if (KMALLOC_MIN_SIZE >= 128) { > - /* > - * The 192 byte sized cache is not used if the alignment > - * is 128 byte. Redirect kmalloc to use the 256 byte cache > - * instead. > - */ > - for (i = 128 + 8; i <= 192; i += 8) > - size_index[size_index_elem(i)] = 8; > - } > -} > - > -static void __init > -new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags) > -{ > - if ((KMALLOC_RECLAIM != KMALLOC_NORMAL) && (type == KMALLOC_RECLAIM)) { > - flags |= SLAB_RECLAIM_ACCOUNT; > - } else if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_CGROUP)) { > - if (mem_cgroup_kmem_disabled()) { > - kmalloc_caches[type][idx] = kmalloc_caches[KMALLOC_NORMAL][idx]; > - return; > - } > - flags |= SLAB_ACCOUNT; > - } else if (IS_ENABLED(CONFIG_ZONE_DMA) && (type == KMALLOC_DMA)) { > - flags |= SLAB_CACHE_DMA; > - } > - > - kmalloc_caches[type][idx] = create_kmalloc_cache( > - kmalloc_info[idx].name[type], > - kmalloc_info[idx].size, flags, 0, > - kmalloc_info[idx].size); > - > - /* > - * If CONFIG_MEMCG_KMEM is enabled, disable cache merging for > - * KMALLOC_NORMAL caches. > - */ > - if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_NORMAL)) > - kmalloc_caches[type][idx]->refcount = -1; > -} > - > -/* > - * Create the kmalloc array. Some of the regular kmalloc arrays > - * may already have been created because they were needed to > - * enable allocations for slab creation. > - */ > -void __init create_kmalloc_caches(slab_flags_t flags) > -{ > - int i; > - enum kmalloc_cache_type type; > - > - /* > - * Including KMALLOC_CGROUP if CONFIG_MEMCG_KMEM defined > - */ > - for (type = KMALLOC_NORMAL; type < NR_KMALLOC_TYPES; type++) { > - for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) { > - if (!kmalloc_caches[type][i]) > - new_kmalloc_cache(i, type, flags); > - > - /* > - * Caches that are not of the two-to-the-power-of size. > - * These have to be created immediately after the > - * earlier power of two caches > - */ > - if (KMALLOC_MIN_SIZE <= 32 && i == 6 && > - !kmalloc_caches[type][1]) > - new_kmalloc_cache(1, type, flags); > - if (KMALLOC_MIN_SIZE <= 64 && i == 7 && > - !kmalloc_caches[type][2]) > - new_kmalloc_cache(2, type, flags); > - } > - } > - > - /* Kmalloc array is now usable */ > - slab_state = UP; > -} > - > -void free_large_kmalloc(struct folio *folio, void *object) > -{ > - unsigned int order = folio_order(folio); > - > - if (WARN_ON_ONCE(order == 0)) > - pr_warn_once("object pointer: 0x%p\n", object); > - > - kmemleak_free(object); > - kasan_kfree_large(object); > - kmsan_kfree_large(object); > - > - mod_lruvec_page_state(folio_page(folio, 0), NR_SLAB_UNRECLAIMABLE_B, > - -(PAGE_SIZE << order)); > - __free_pages(folio_page(folio, 0), order); > -} > - > -static void *__kmalloc_large_node(size_t size, gfp_t flags, int node); > -static __always_inline > -void *__do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller) > -{ > - struct kmem_cache *s; > - void *ret; > - > - if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) { > - ret = __kmalloc_large_node(size, flags, node); > - trace_kmalloc(caller, ret, size, > - PAGE_SIZE << get_order(size), flags, node); > - return ret; > - } > - > - s = kmalloc_slab(size, flags); > - > - if (unlikely(ZERO_OR_NULL_PTR(s))) > - return s; > - > - ret = __kmem_cache_alloc_node(s, flags, node, size, caller); > - ret = kasan_kmalloc(s, ret, size, flags); > - trace_kmalloc(caller, ret, size, s->size, flags, node); > - return ret; > -} > - > -void *__kmalloc_node(size_t size, gfp_t flags, int node) > -{ > - return __do_kmalloc_node(size, flags, node, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc_node); > - > -void *__kmalloc(size_t size, gfp_t flags) > -{ > - return __do_kmalloc_node(size, flags, NUMA_NO_NODE, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc); > - > -void *__kmalloc_node_track_caller(size_t size, gfp_t flags, > - int node, unsigned long caller) > -{ > - return __do_kmalloc_node(size, flags, node, caller); > -} > -EXPORT_SYMBOL(__kmalloc_node_track_caller); > - > -/** > - * kfree - free previously allocated memory > - * @object: pointer returned by kmalloc. > - * > - * If @object is NULL, no operation is performed. > - * > - * Don't free memory not originally allocated by kmalloc() > - * or you will run into trouble. > - */ > -void kfree(const void *object) > -{ > - struct folio *folio; > - struct slab *slab; > - struct kmem_cache *s; > - > - trace_kfree(_RET_IP_, object); > - > - if (unlikely(ZERO_OR_NULL_PTR(object))) > - return; > - > - folio = virt_to_folio(object); > - if (unlikely(!folio_test_slab(folio))) { > - free_large_kmalloc(folio, (void *)object); > - return; > - } > - > - slab = folio_slab(folio); > - s = slab->slab_cache; > - __kmem_cache_free(s, (void *)object, _RET_IP_); > -} > -EXPORT_SYMBOL(kfree); > - > -/** > - * __ksize -- Report full size of underlying allocation > - * @object: pointer to the object > - * > - * This should only be used internally to query the true size of allocations. > - * It is not meant to be a way to discover the usable size of an allocation > - * after the fact. Instead, use kmalloc_size_roundup(). Using memory beyond > - * the originally requested allocation size may trigger KASAN, UBSAN_BOUNDS, > - * and/or FORTIFY_SOURCE. > - * > - * Return: size of the actual memory used by @object in bytes > - */ > -size_t __ksize(const void *object) > -{ > - struct folio *folio; > - > - if (unlikely(object == ZERO_SIZE_PTR)) > - return 0; > - > - folio = virt_to_folio(object); > - > - if (unlikely(!folio_test_slab(folio))) { > - if (WARN_ON(folio_size(folio) <= KMALLOC_MAX_CACHE_SIZE)) > - return 0; > - if (WARN_ON(object != folio_address(folio))) > - return 0; > - return folio_size(folio); > - } > - > -#ifdef CONFIG_SLUB_DEBUG > - skip_orig_size_check(folio_slab(folio)->slab_cache, object); > -#endif > - > - return slab_ksize(folio_slab(folio)->slab_cache); > -} > - > -void *kmalloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size) > -{ > - void *ret = __kmem_cache_alloc_node(s, gfpflags, NUMA_NO_NODE, > - size, _RET_IP_); > - > - trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags, NUMA_NO_NODE); > - > - ret = kasan_kmalloc(s, ret, size, gfpflags); > - return ret; > -} > -EXPORT_SYMBOL(kmalloc_trace); > - > -void *kmalloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, > - int node, size_t size) > -{ > - void *ret = __kmem_cache_alloc_node(s, gfpflags, node, size, _RET_IP_); > - > - trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags, node); > - > - ret = kasan_kmalloc(s, ret, size, gfpflags); > - return ret; > -} > -EXPORT_SYMBOL(kmalloc_node_trace); > -#endif /* !CONFIG_SLOB */ > - > gfp_t kmalloc_fix_flags(gfp_t flags) > { > gfp_t invalid_mask = flags & GFP_SLAB_BUG_MASK; > @@ -1144,202 +684,44 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) > } > EXPORT_SYMBOL(kmalloc_large_node); > > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -/* Randomize a generic freelist */ > -static void freelist_randomize(struct rnd_state *state, unsigned int *list, > - unsigned int count) > -{ > - unsigned int rand; > - unsigned int i; > - > - for (i = 0; i < count; i++) > - list[i] = i; > - > - /* Fisher-Yates shuffle */ > - for (i = count - 1; i > 0; i--) { > - rand = prandom_u32_state(state); > - rand %= (i + 1); > - swap(list[i], list[rand]); > - } > -} > - > -/* Create a random sequence per cache */ > -int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, > - gfp_t gfp) > -{ > - struct rnd_state state; > - > - if (count < 2 || cachep->random_seq) > - return 0; > - > - cachep->random_seq = kcalloc(count, sizeof(unsigned int), gfp); > - if (!cachep->random_seq) > - return -ENOMEM; > - > - /* Get best entropy at this stage of boot */ > - prandom_seed_state(&state, get_random_long()); > - > - freelist_randomize(&state, cachep->random_seq, count); > - return 0; > -} > - > -/* Destroy the per-cache random freelist sequence */ > -void cache_random_seq_destroy(struct kmem_cache *cachep) > -{ > - kfree(cachep->random_seq); > - cachep->random_seq = NULL; > -} > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > - > -#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG) > -#ifdef CONFIG_SLAB > -#define SLABINFO_RIGHTS (0600) > -#else > -#define SLABINFO_RIGHTS (0400) > -#endif > - > -static void print_slabinfo_header(struct seq_file *m) > -{ > - /* > - * Output format version, so at least we can change it > - * without _too_ many complaints. > - */ > -#ifdef CONFIG_DEBUG_SLAB > - seq_puts(m, "slabinfo - version: 2.1 (statistics)\n"); > -#else > - seq_puts(m, "slabinfo - version: 2.1\n"); > -#endif > - seq_puts(m, "# name <active_objs> <num_objs> <objsize> <objperslab> <pagesperslab>"); > - seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>"); > - seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>"); > -#ifdef CONFIG_DEBUG_SLAB > - seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> <error> <maxfreeable> <nodeallocs> <remotefrees> <alienoverflow>"); > - seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>"); > -#endif > - seq_putc(m, '\n'); > -} > - > -static void *slab_start(struct seq_file *m, loff_t *pos) > -{ > - mutex_lock(&slab_mutex); > - return seq_list_start(&slab_caches, *pos); > -} > - > -static void *slab_next(struct seq_file *m, void *p, loff_t *pos) > -{ > - return seq_list_next(p, &slab_caches, pos); > -} > - > -static void slab_stop(struct seq_file *m, void *p) > -{ > - mutex_unlock(&slab_mutex); > -} > - > -static void cache_show(struct kmem_cache *s, struct seq_file *m) > +static __always_inline void * > +__do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) > { > - struct slabinfo sinfo; > + void *ret; > > - memset(&sinfo, 0, sizeof(sinfo)); > - get_slabinfo(s, &sinfo); > + gfp &= gfp_allowed_mask; > > - seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", > - s->name, sinfo.active_objs, sinfo.num_objs, s->size, > - sinfo.objects_per_slab, (1 << sinfo.cache_order)); > + might_alloc(gfp); > > - seq_printf(m, " : tunables %4u %4u %4u", > - sinfo.limit, sinfo.batchcount, sinfo.shared); > - seq_printf(m, " : slabdata %6lu %6lu %6lu", > - sinfo.active_slabs, sinfo.num_slabs, sinfo.shared_avail); > - slabinfo_show_stats(m, s); > - seq_putc(m, '\n'); > -} > + if (unlikely(!size)) > + ret = ZERO_SIZE_PTR; > + else > + ret = __kmalloc_large_node(size, gfp, node); > > -static int slab_show(struct seq_file *m, void *p) > -{ > - struct kmem_cache *s = list_entry(p, struct kmem_cache, list); > + trace_kmalloc(caller, ret, size, PAGE_SIZE << get_order(size), gfp, node); > > - if (p == slab_caches.next) > - print_slabinfo_header(m); > - cache_show(s, m); > - return 0; > + kmemleak_alloc(ret, size, 1, gfp); > + return ret; > } > > -void dump_unreclaimable_slab(void) > +void *__kmalloc(size_t size, gfp_t gfp) > { > - struct kmem_cache *s; > - struct slabinfo sinfo; > - > - /* > - * Here acquiring slab_mutex is risky since we don't prefer to get > - * sleep in oom path. But, without mutex hold, it may introduce a > - * risk of crash. > - * Use mutex_trylock to protect the list traverse, dump nothing > - * without acquiring the mutex. > - */ > - if (!mutex_trylock(&slab_mutex)) { > - pr_warn("excessive unreclaimable slab but cannot dump stats\n"); > - return; > - } > - > - pr_info("Unreclaimable slab info:\n"); > - pr_info("Name Used Total\n"); > - > - list_for_each_entry(s, &slab_caches, list) { > - if (s->flags & SLAB_RECLAIM_ACCOUNT) > - continue; > - > - get_slabinfo(s, &sinfo); > - > - if (sinfo.num_objs > 0) > - pr_info("%-17s %10luKB %10luKB\n", s->name, > - (sinfo.active_objs * s->size) / 1024, > - (sinfo.num_objs * s->size) / 1024); > - } > - mutex_unlock(&slab_mutex); > + return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_); > } > +EXPORT_SYMBOL(__kmalloc); > > -/* > - * slabinfo_op - iterator that generates /proc/slabinfo > - * > - * Output layout: > - * cache-name > - * num-active-objs > - * total-objs > - * object size > - * num-active-slabs > - * total-slabs > - * num-pages-per-slab > - * + further values on SMP and with statistics enabled > - */ > -static const struct seq_operations slabinfo_op = { > - .start = slab_start, > - .next = slab_next, > - .stop = slab_stop, > - .show = slab_show, > -}; > - > -static int slabinfo_open(struct inode *inode, struct file *file) > +void *__kmalloc_node(size_t size, gfp_t gfp, int node) > { > - return seq_open(file, &slabinfo_op); > + return __do_kmalloc_node(size, gfp, node, _RET_IP_); > } > +EXPORT_SYMBOL(__kmalloc_node); > > -static const struct proc_ops slabinfo_proc_ops = { > - .proc_flags = PROC_ENTRY_PERMANENT, > - .proc_open = slabinfo_open, > - .proc_read = seq_read, > - .proc_write = slabinfo_write, > - .proc_lseek = seq_lseek, > - .proc_release = seq_release, > -}; > - > -static int __init slab_proc_init(void) > +void *__kmalloc_node_track_caller(size_t size, gfp_t gfp, > + int node, unsigned long caller) > { > - proc_create("slabinfo", SLABINFO_RIGHTS, NULL, &slabinfo_proc_ops); > - return 0; > + return __do_kmalloc_node(size, gfp, node, caller); > } > -module_init(slab_proc_init); > - > -#endif /* CONFIG_SLAB || CONFIG_SLUB_DEBUG */ > +EXPORT_SYMBOL(__kmalloc_node_track_caller); > > static __always_inline __realloc_size(2) void * > __do_krealloc(const void *p, size_t new_size, gfp_t flags) > @@ -1402,6 +784,27 @@ void *krealloc(const void *p, size_t new_size, gfp_t flags) > } > EXPORT_SYMBOL(krealloc); > > +void kfree(const void *block) > +{ > + struct folio *sp; > + unsigned int order; > + > + trace_kfree(_RET_IP_, block); > + > + if (unlikely(ZERO_OR_NULL_PTR(block))) > + return; > + kmemleak_free(block); > + > + sp = virt_to_folio(block); > + BUG_ON(folio_test_slab(sp)); > + order = folio_order(sp); > + > + mod_node_page_state(folio_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > + -(PAGE_SIZE << order)); > + __free_pages(folio_page(sp, 0), order); > +} > +EXPORT_SYMBOL(kfree); > + > /** > * kfree_sensitive - Clear sensitive information in memory before freeing > * @p: object to free memory of > @@ -1427,6 +830,34 @@ void kfree_sensitive(const void *p) > } > EXPORT_SYMBOL(kfree_sensitive); > > +size_t kmalloc_size_roundup(size_t size) > +{ > + /* Short-circuit the 0 size case. */ > + if (unlikely(size == 0)) > + return 0; > + /* Short-circuit saturated "too-large" case. */ > + if (unlikely(size == SIZE_MAX)) > + return SIZE_MAX; > + > + return PAGE_SIZE << get_order(size); > +} > + > +EXPORT_SYMBOL(kmalloc_size_roundup); > + > +/* can't use ksize for kmem_cache_alloc memory, only kmalloc */ > +size_t __ksize(const void *block) > +{ > + struct folio *folio; > + > + BUG_ON(!block); > + if (unlikely(block == ZERO_SIZE_PTR)) > + return 0; > + > + folio = virt_to_folio(block); > + BUG_ON(folio_test_slab(folio)); > + return folio_size(folio); > +} > + > size_t ksize(const void *objp) > { > /* > @@ -1451,6 +882,131 @@ size_t ksize(const void *objp) > } > EXPORT_SYMBOL(ksize); > > +static void *__kmem_cache_alloc_node(struct kmem_cache *c, gfp_t flags, int node) > +{ > + void *b; > + > + flags &= gfp_allowed_mask; > + > + might_alloc(flags); > + > + b = __kmalloc_large_node(c->size, flags, node); > + trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); > + > + if (b && c->ctor) { > + WARN_ON_ONCE(flags & __GFP_ZERO); > + c->ctor(b); > + } > + > + kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); > + return b; > +} > + > +void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) > +{ > + return __kmem_cache_alloc_node(cachep, flags, NUMA_NO_NODE); > +} > +EXPORT_SYMBOL(kmem_cache_alloc); > + > + > +void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags) > +{ > + return __kmem_cache_alloc_node(cachep, flags, NUMA_NO_NODE); > +} > +EXPORT_SYMBOL(kmem_cache_alloc_lru); > + > +void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node) > +{ > + return __kmem_cache_alloc_node(cachep, gfp, node); > +} > +EXPORT_SYMBOL(kmem_cache_alloc_node); > + > +static void kmem_rcu_free(struct rcu_head *head) > +{ > + struct slab_rcu *slab_rcu = (struct slab_rcu *)head; > + void *b = (void *)slab_rcu - (slab_rcu->size - sizeof(struct slab_rcu)); > + > + kfree(b); > +} > + > +void kmem_cache_free(struct kmem_cache *c, void *b) > +{ > + kmemleak_free_recursive(b, c->flags); > + trace_kmem_cache_free(_RET_IP_, b, c); > + if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) { > + struct slab_rcu *slab_rcu; > + slab_rcu = b + (c->size - sizeof(struct slab_rcu)); > + slab_rcu->size = c->size; > + call_rcu(&slab_rcu->head, kmem_rcu_free); > + } else { > + kfree(b); > + } > +} > +EXPORT_SYMBOL(kmem_cache_free); > + > +void kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p) > +{ > + size_t i; > + > + for (i = 0; i < nr; i++) { > + if (s) > + kmem_cache_free(s, p[i]); > + else > + kfree(p[i]); > + } > +} > +EXPORT_SYMBOL(kmem_cache_free_bulk); > + > +int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr, > + void **p) > +{ > + size_t i; > + > + for (i = 0; i < nr; i++) { > + void *x = p[i] = kmem_cache_alloc(s, flags); > + > + if (!x) { > + kmem_cache_free_bulk(s, i, p); > + return 0; > + } > + } > + return i; > +} > +EXPORT_SYMBOL(kmem_cache_alloc_bulk); > + > +int __kmem_cache_shutdown(struct kmem_cache *c) > +{ > + /* No way to check for remaining objects */ > + return 0; > +} > + > +void __kmem_cache_release(struct kmem_cache *c) > +{ > +} > + > +int __kmem_cache_shrink(struct kmem_cache *d) > +{ > + return 0; > +} > + > +static struct kmem_cache kmem_cache_boot = { > + .name = "kmem_cache", > + .size = sizeof(struct kmem_cache), > + .flags = SLAB_PANIC, > + .align = ARCH_KMALLOC_MINALIGN, > +}; > + > +void __init kmem_cache_init(void) > +{ > + kmem_cache = &kmem_cache_boot; > + slab_state = UP; > +} > + > +void __init kmem_cache_init_late(void) > +{ > + slab_state = FULL; > +} > + > /* Tracepoints definitions. */ > EXPORT_TRACEPOINT_SYMBOL(kmalloc); > EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc); > diff --git a/mm/slob.c b/mm/slob.c > deleted file mode 100644 > index fe567fcfa3a3..000000000000 > --- a/mm/slob.c > +++ /dev/null > @@ -1,757 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * SLOB Allocator: Simple List Of Blocks > - * > - * Matt Mackall <mpm@selenic.com> 12/30/03 > - * > - * NUMA support by Paul Mundt, 2007. > - * > - * How SLOB works: > - * > - * The core of SLOB is a traditional K&R style heap allocator, with > - * support for returning aligned objects. The granularity of this > - * allocator is as little as 2 bytes, however typically most architectures > - * will require 4 bytes on 32-bit and 8 bytes on 64-bit. > - * > - * The slob heap is a set of linked list of pages from alloc_pages(), > - * and within each page, there is a singly-linked list of free blocks > - * (slob_t). The heap is grown on demand. To reduce fragmentation, > - * heap pages are segregated into three lists, with objects less than > - * 256 bytes, objects less than 1024 bytes, and all other objects. > - * > - * Allocation from heap involves first searching for a page with > - * sufficient free blocks (using a next-fit-like approach) followed by > - * a first-fit scan of the page. Deallocation inserts objects back > - * into the free list in address order, so this is effectively an > - * address-ordered first fit. > - * > - * Above this is an implementation of kmalloc/kfree. Blocks returned > - * from kmalloc are prepended with a 4-byte header with the kmalloc size. > - * If kmalloc is asked for objects of PAGE_SIZE or larger, it calls > - * alloc_pages() directly, allocating compound pages so the page order > - * does not have to be separately tracked. > - * These objects are detected in kfree() because folio_test_slab() > - * is false for them. > - * > - * SLAB is emulated on top of SLOB by simply calling constructors and > - * destructors for every SLAB allocation. Objects are returned with the > - * 4-byte alignment unless the SLAB_HWCACHE_ALIGN flag is set, in which > - * case the low-level allocator will fragment blocks to create the proper > - * alignment. Again, objects of page-size or greater are allocated by > - * calling alloc_pages(). As SLAB objects know their size, no separate > - * size bookkeeping is necessary and there is essentially no allocation > - * space overhead, and compound pages aren't needed for multi-page > - * allocations. > - * > - * NUMA support in SLOB is fairly simplistic, pushing most of the real > - * logic down to the page allocator, and simply doing the node accounting > - * on the upper levels. In the event that a node id is explicitly > - * provided, __alloc_pages_node() with the specified node id is used > - * instead. The common case (or when the node id isn't explicitly provided) > - * will default to the current node, as per numa_node_id(). > - * > - * Node aware pages are still inserted in to the global freelist, and > - * these are scanned for by matching against the node id encoded in the > - * page flags. As a result, block allocations that can be satisfied from > - * the freelist will only be done so on pages residing on the same node, > - * in order to prevent random node placement. > - */ > - > -#include <linux/kernel.h> > -#include <linux/slab.h> > - > -#include <linux/mm.h> > -#include <linux/swap.h> /* struct reclaim_state */ > -#include <linux/cache.h> > -#include <linux/init.h> > -#include <linux/export.h> > -#include <linux/rcupdate.h> > -#include <linux/list.h> > -#include <linux/kmemleak.h> > - > -#include <trace/events/kmem.h> > - > -#include <linux/atomic.h> > - > -#include "slab.h" > -/* > - * slob_block has a field 'units', which indicates size of block if +ve, > - * or offset of next block if -ve (in SLOB_UNITs). > - * > - * Free blocks of size 1 unit simply contain the offset of the next block. > - * Those with larger size contain their size in the first SLOB_UNIT of > - * memory, and the offset of the next free block in the second SLOB_UNIT. > - */ > -#if PAGE_SIZE <= (32767 * 2) > -typedef s16 slobidx_t; > -#else > -typedef s32 slobidx_t; > -#endif > - > -struct slob_block { > - slobidx_t units; > -}; > -typedef struct slob_block slob_t; > - > -/* > - * All partially free slob pages go on these lists. > - */ > -#define SLOB_BREAK1 256 > -#define SLOB_BREAK2 1024 > -static LIST_HEAD(free_slob_small); > -static LIST_HEAD(free_slob_medium); > -static LIST_HEAD(free_slob_large); > - > -/* > - * slob_page_free: true for pages on free_slob_pages list. > - */ > -static inline int slob_page_free(struct slab *slab) > -{ > - return PageSlobFree(slab_page(slab)); > -} > - > -static void set_slob_page_free(struct slab *slab, struct list_head *list) > -{ > - list_add(&slab->slab_list, list); > - __SetPageSlobFree(slab_page(slab)); > -} > - > -static inline void clear_slob_page_free(struct slab *slab) > -{ > - list_del(&slab->slab_list); > - __ClearPageSlobFree(slab_page(slab)); > -} > - > -#define SLOB_UNIT sizeof(slob_t) > -#define SLOB_UNITS(size) DIV_ROUND_UP(size, SLOB_UNIT) > - > -/* > - * struct slob_rcu is inserted at the tail of allocated slob blocks, which > - * were created with a SLAB_TYPESAFE_BY_RCU slab. slob_rcu is used to free > - * the block using call_rcu. > - */ > -struct slob_rcu { > - struct rcu_head head; > - int size; > -}; > - > -/* > - * slob_lock protects all slob allocator structures. > - */ > -static DEFINE_SPINLOCK(slob_lock); > - > -/* > - * Encode the given size and next info into a free slob block s. > - */ > -static void set_slob(slob_t *s, slobidx_t size, slob_t *next) > -{ > - slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); > - slobidx_t offset = next - base; > - > - if (size > 1) { > - s[0].units = size; > - s[1].units = offset; > - } else > - s[0].units = -offset; > -} > - > -/* > - * Return the size of a slob block. > - */ > -static slobidx_t slob_units(slob_t *s) > -{ > - if (s->units > 0) > - return s->units; > - return 1; > -} > - > -/* > - * Return the next free slob block pointer after this one. > - */ > -static slob_t *slob_next(slob_t *s) > -{ > - slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); > - slobidx_t next; > - > - if (s[0].units < 0) > - next = -s[0].units; > - else > - next = s[1].units; > - return base+next; > -} > - > -/* > - * Returns true if s is the last free block in its page. > - */ > -static int slob_last(slob_t *s) > -{ > - return !((unsigned long)slob_next(s) & ~PAGE_MASK); > -} > - > -static void *slob_new_pages(gfp_t gfp, int order, int node) > -{ > - struct page *page; > - > -#ifdef CONFIG_NUMA > - if (node != NUMA_NO_NODE) > - page = __alloc_pages_node(node, gfp, order); > - else > -#endif > - page = alloc_pages(gfp, order); > - > - if (!page) > - return NULL; > - > - mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE_B, > - PAGE_SIZE << order); > - return page_address(page); > -} > - > -static void slob_free_pages(void *b, int order) > -{ > - struct page *sp = virt_to_page(b); > - > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += 1 << order; > - > - mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > - -(PAGE_SIZE << order)); > - __free_pages(sp, order); > -} > - > -/* > - * slob_page_alloc() - Allocate a slob block within a given slob_page sp. > - * @sp: Page to look in. > - * @size: Size of the allocation. > - * @align: Allocation alignment. > - * @align_offset: Offset in the allocated block that will be aligned. > - * @page_removed_from_list: Return parameter. > - * > - * Tries to find a chunk of memory at least @size bytes big within @page. > - * > - * Return: Pointer to memory if allocated, %NULL otherwise. If the > - * allocation fills up @page then the page is removed from the > - * freelist, in this case @page_removed_from_list will be set to > - * true (set to false otherwise). > - */ > -static void *slob_page_alloc(struct slab *sp, size_t size, int align, > - int align_offset, bool *page_removed_from_list) > -{ > - slob_t *prev, *cur, *aligned = NULL; > - int delta = 0, units = SLOB_UNITS(size); > - > - *page_removed_from_list = false; > - for (prev = NULL, cur = sp->freelist; ; prev = cur, cur = slob_next(cur)) { > - slobidx_t avail = slob_units(cur); > - > - /* > - * 'aligned' will hold the address of the slob block so that the > - * address 'aligned'+'align_offset' is aligned according to the > - * 'align' parameter. This is for kmalloc() which prepends the > - * allocated block with its size, so that the block itself is > - * aligned when needed. > - */ > - if (align) { > - aligned = (slob_t *) > - (ALIGN((unsigned long)cur + align_offset, align) > - - align_offset); > - delta = aligned - cur; > - } > - if (avail >= units + delta) { /* room enough? */ > - slob_t *next; > - > - if (delta) { /* need to fragment head to align? */ > - next = slob_next(cur); > - set_slob(aligned, avail - delta, next); > - set_slob(cur, delta, aligned); > - prev = cur; > - cur = aligned; > - avail = slob_units(cur); > - } > - > - next = slob_next(cur); > - if (avail == units) { /* exact fit? unlink. */ > - if (prev) > - set_slob(prev, slob_units(prev), next); > - else > - sp->freelist = next; > - } else { /* fragment */ > - if (prev) > - set_slob(prev, slob_units(prev), cur + units); > - else > - sp->freelist = cur + units; > - set_slob(cur + units, avail - units, next); > - } > - > - sp->units -= units; > - if (!sp->units) { > - clear_slob_page_free(sp); > - *page_removed_from_list = true; > - } > - return cur; > - } > - if (slob_last(cur)) > - return NULL; > - } > -} > - > -/* > - * slob_alloc: entry point into the slob allocator. > - */ > -static void *slob_alloc(size_t size, gfp_t gfp, int align, int node, > - int align_offset) > -{ > - struct folio *folio; > - struct slab *sp; > - struct list_head *slob_list; > - slob_t *b = NULL; > - unsigned long flags; > - bool _unused; > - > - if (size < SLOB_BREAK1) > - slob_list = &free_slob_small; > - else if (size < SLOB_BREAK2) > - slob_list = &free_slob_medium; > - else > - slob_list = &free_slob_large; > - > - spin_lock_irqsave(&slob_lock, flags); > - /* Iterate through each partially free page, try to find room */ > - list_for_each_entry(sp, slob_list, slab_list) { > - bool page_removed_from_list = false; > -#ifdef CONFIG_NUMA > - /* > - * If there's a node specification, search for a partial > - * page with a matching node id in the freelist. > - */ > - if (node != NUMA_NO_NODE && slab_nid(sp) != node) > - continue; > -#endif > - /* Enough room on this page? */ > - if (sp->units < SLOB_UNITS(size)) > - continue; > - > - b = slob_page_alloc(sp, size, align, align_offset, &page_removed_from_list); > - if (!b) > - continue; > - > - /* > - * If slob_page_alloc() removed sp from the list then we > - * cannot call list functions on sp. If so allocation > - * did not fragment the page anyway so optimisation is > - * unnecessary. > - */ > - if (!page_removed_from_list) { > - /* > - * Improve fragment distribution and reduce our average > - * search time by starting our next search here. (see > - * Knuth vol 1, sec 2.5, pg 449) > - */ > - if (!list_is_first(&sp->slab_list, slob_list)) > - list_rotate_to_front(&sp->slab_list, slob_list); > - } > - break; > - } > - spin_unlock_irqrestore(&slob_lock, flags); > - > - /* Not enough space: must allocate a new page */ > - if (!b) { > - b = slob_new_pages(gfp & ~__GFP_ZERO, 0, node); > - if (!b) > - return NULL; > - folio = virt_to_folio(b); > - __folio_set_slab(folio); > - sp = folio_slab(folio); > - > - spin_lock_irqsave(&slob_lock, flags); > - sp->units = SLOB_UNITS(PAGE_SIZE); > - sp->freelist = b; > - INIT_LIST_HEAD(&sp->slab_list); > - set_slob(b, SLOB_UNITS(PAGE_SIZE), b + SLOB_UNITS(PAGE_SIZE)); > - set_slob_page_free(sp, slob_list); > - b = slob_page_alloc(sp, size, align, align_offset, &_unused); > - BUG_ON(!b); > - spin_unlock_irqrestore(&slob_lock, flags); > - } > - if (unlikely(gfp & __GFP_ZERO)) > - memset(b, 0, size); > - return b; > -} > - > -/* > - * slob_free: entry point into the slob allocator. > - */ > -static void slob_free(void *block, int size) > -{ > - struct slab *sp; > - slob_t *prev, *next, *b = (slob_t *)block; > - slobidx_t units; > - unsigned long flags; > - struct list_head *slob_list; > - > - if (unlikely(ZERO_OR_NULL_PTR(block))) > - return; > - BUG_ON(!size); > - > - sp = virt_to_slab(block); > - units = SLOB_UNITS(size); > - > - spin_lock_irqsave(&slob_lock, flags); > - > - if (sp->units + units == SLOB_UNITS(PAGE_SIZE)) { > - /* Go directly to page allocator. Do not pass slob allocator */ > - if (slob_page_free(sp)) > - clear_slob_page_free(sp); > - spin_unlock_irqrestore(&slob_lock, flags); > - __folio_clear_slab(slab_folio(sp)); > - slob_free_pages(b, 0); > - return; > - } > - > - if (!slob_page_free(sp)) { > - /* This slob page is about to become partially free. Easy! */ > - sp->units = units; > - sp->freelist = b; > - set_slob(b, units, > - (void *)((unsigned long)(b + > - SLOB_UNITS(PAGE_SIZE)) & PAGE_MASK)); > - if (size < SLOB_BREAK1) > - slob_list = &free_slob_small; > - else if (size < SLOB_BREAK2) > - slob_list = &free_slob_medium; > - else > - slob_list = &free_slob_large; > - set_slob_page_free(sp, slob_list); > - goto out; > - } > - > - /* > - * Otherwise the page is already partially free, so find reinsertion > - * point. > - */ > - sp->units += units; > - > - if (b < (slob_t *)sp->freelist) { > - if (b + units == sp->freelist) { > - units += slob_units(sp->freelist); > - sp->freelist = slob_next(sp->freelist); > - } > - set_slob(b, units, sp->freelist); > - sp->freelist = b; > - } else { > - prev = sp->freelist; > - next = slob_next(prev); > - while (b > next) { > - prev = next; > - next = slob_next(prev); > - } > - > - if (!slob_last(prev) && b + units == next) { > - units += slob_units(next); > - set_slob(b, units, slob_next(next)); > - } else > - set_slob(b, units, next); > - > - if (prev + slob_units(prev) == b) { > - units = slob_units(b) + slob_units(prev); > - set_slob(prev, units, slob_next(b)); > - } else > - set_slob(prev, slob_units(prev), b); > - } > -out: > - spin_unlock_irqrestore(&slob_lock, flags); > -} > - > -#ifdef CONFIG_PRINTK > -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) > -{ > - kpp->kp_ptr = object; > - kpp->kp_slab = slab; > -} > -#endif > - > -/* > - * End of slob allocator proper. Begin kmem_cache_alloc and kmalloc frontend. > - */ > - > -static __always_inline void * > -__do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) > -{ > - unsigned int *m; > - unsigned int minalign; > - void *ret; > - > - minalign = max_t(unsigned int, ARCH_KMALLOC_MINALIGN, > - arch_slab_minalign()); > - gfp &= gfp_allowed_mask; > - > - might_alloc(gfp); > - > - if (size < PAGE_SIZE - minalign) { > - int align = minalign; > - > - /* > - * For power of two sizes, guarantee natural alignment for > - * kmalloc()'d objects. > - */ > - if (is_power_of_2(size)) > - align = max_t(unsigned int, minalign, size); > - > - if (!size) > - return ZERO_SIZE_PTR; > - > - m = slob_alloc(size + minalign, gfp, align, node, minalign); > - > - if (!m) > - return NULL; > - *m = size; > - ret = (void *)m + minalign; > - > - trace_kmalloc(caller, ret, size, size + minalign, gfp, node); > - } else { > - unsigned int order = get_order(size); > - > - if (likely(order)) > - gfp |= __GFP_COMP; > - ret = slob_new_pages(gfp, order, node); > - > - trace_kmalloc(caller, ret, size, PAGE_SIZE << order, gfp, node); > - } > - > - kmemleak_alloc(ret, size, 1, gfp); > - return ret; > -} > - > -void *__kmalloc(size_t size, gfp_t gfp) > -{ > - return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc); > - > -void *__kmalloc_node_track_caller(size_t size, gfp_t gfp, > - int node, unsigned long caller) > -{ > - return __do_kmalloc_node(size, gfp, node, caller); > -} > -EXPORT_SYMBOL(__kmalloc_node_track_caller); > - > -void kfree(const void *block) > -{ > - struct folio *sp; > - > - trace_kfree(_RET_IP_, block); > - > - if (unlikely(ZERO_OR_NULL_PTR(block))) > - return; > - kmemleak_free(block); > - > - sp = virt_to_folio(block); > - if (folio_test_slab(sp)) { > - unsigned int align = max_t(unsigned int, > - ARCH_KMALLOC_MINALIGN, > - arch_slab_minalign()); > - unsigned int *m = (unsigned int *)(block - align); > - > - slob_free(m, *m + align); > - } else { > - unsigned int order = folio_order(sp); > - > - mod_node_page_state(folio_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > - -(PAGE_SIZE << order)); > - __free_pages(folio_page(sp, 0), order); > - > - } > -} > -EXPORT_SYMBOL(kfree); > - > -size_t kmalloc_size_roundup(size_t size) > -{ > - /* Short-circuit the 0 size case. */ > - if (unlikely(size == 0)) > - return 0; > - /* Short-circuit saturated "too-large" case. */ > - if (unlikely(size == SIZE_MAX)) > - return SIZE_MAX; > - > - return ALIGN(size, ARCH_KMALLOC_MINALIGN); > -} > - > -EXPORT_SYMBOL(kmalloc_size_roundup); > - > -/* can't use ksize for kmem_cache_alloc memory, only kmalloc */ > -size_t __ksize(const void *block) > -{ > - struct folio *folio; > - unsigned int align; > - unsigned int *m; > - > - BUG_ON(!block); > - if (unlikely(block == ZERO_SIZE_PTR)) > - return 0; > - > - folio = virt_to_folio(block); > - if (unlikely(!folio_test_slab(folio))) > - return folio_size(folio); > - > - align = max_t(unsigned int, ARCH_KMALLOC_MINALIGN, > - arch_slab_minalign()); > - m = (unsigned int *)(block - align); > - return SLOB_UNITS(*m) * SLOB_UNIT; > -} > - > -int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags) > -{ > - if (flags & SLAB_TYPESAFE_BY_RCU) { > - /* leave room for rcu footer at the end of object */ > - c->size += sizeof(struct slob_rcu); > - } > - > - /* Actual size allocated */ > - c->size = SLOB_UNITS(c->size) * SLOB_UNIT; > - c->flags = flags; > - return 0; > -} > - > -static void *slob_alloc_node(struct kmem_cache *c, gfp_t flags, int node) > -{ > - void *b; > - > - flags &= gfp_allowed_mask; > - > - might_alloc(flags); > - > - if (c->size < PAGE_SIZE) { > - b = slob_alloc(c->size, flags, c->align, node, 0); > - trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); > - } else { > - b = slob_new_pages(flags, get_order(c->size), node); > - trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); > - } > - > - if (b && c->ctor) { > - WARN_ON_ONCE(flags & __GFP_ZERO); > - c->ctor(b); > - } > - > - kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); > - return b; > -} > - > -void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - return slob_alloc_node(cachep, flags, NUMA_NO_NODE); > -} > -EXPORT_SYMBOL(kmem_cache_alloc); > - > - > -void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags) > -{ > - return slob_alloc_node(cachep, flags, NUMA_NO_NODE); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_lru); > - > -void *__kmalloc_node(size_t size, gfp_t gfp, int node) > -{ > - return __do_kmalloc_node(size, gfp, node, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc_node); > - > -void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node) > -{ > - return slob_alloc_node(cachep, gfp, node); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_node); > - > -static void __kmem_cache_free(void *b, int size) > -{ > - if (size < PAGE_SIZE) > - slob_free(b, size); > - else > - slob_free_pages(b, get_order(size)); > -} > - > -static void kmem_rcu_free(struct rcu_head *head) > -{ > - struct slob_rcu *slob_rcu = (struct slob_rcu *)head; > - void *b = (void *)slob_rcu - (slob_rcu->size - sizeof(struct slob_rcu)); > - > - __kmem_cache_free(b, slob_rcu->size); > -} > - > -void kmem_cache_free(struct kmem_cache *c, void *b) > -{ > - kmemleak_free_recursive(b, c->flags); > - trace_kmem_cache_free(_RET_IP_, b, c); > - if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) { > - struct slob_rcu *slob_rcu; > - slob_rcu = b + (c->size - sizeof(struct slob_rcu)); > - slob_rcu->size = c->size; > - call_rcu(&slob_rcu->head, kmem_rcu_free); > - } else { > - __kmem_cache_free(b, c->size); > - } > -} > -EXPORT_SYMBOL(kmem_cache_free); > - > -void kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p) > -{ > - size_t i; > - > - for (i = 0; i < nr; i++) { > - if (s) > - kmem_cache_free(s, p[i]); > - else > - kfree(p[i]); > - } > -} > -EXPORT_SYMBOL(kmem_cache_free_bulk); > - > -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr, > - void **p) > -{ > - size_t i; > - > - for (i = 0; i < nr; i++) { > - void *x = p[i] = kmem_cache_alloc(s, flags); > - > - if (!x) { > - kmem_cache_free_bulk(s, i, p); > - return 0; > - } > - } > - return i; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_bulk); > - > -int __kmem_cache_shutdown(struct kmem_cache *c) > -{ > - /* No way to check for remaining objects */ > - return 0; > -} > - > -void __kmem_cache_release(struct kmem_cache *c) > -{ > -} > - > -int __kmem_cache_shrink(struct kmem_cache *d) > -{ > - return 0; > -} > - > -static struct kmem_cache kmem_cache_boot = { > - .name = "kmem_cache", > - .size = sizeof(struct kmem_cache), > - .flags = SLAB_PANIC, > - .align = ARCH_KMALLOC_MINALIGN, > -}; > - > -void __init kmem_cache_init(void) > -{ > - kmem_cache = &kmem_cache_boot; > - slab_state = UP; > -} > - > -void __init kmem_cache_init_late(void) > -{ > - slab_state = FULL; > -} > diff --git a/mm/slub.c b/mm/slub.c > deleted file mode 100644 > index 39327e98fce3..000000000000 > --- a/mm/slub.c > +++ /dev/null > @@ -1,6506 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * SLUB: A slab allocator that limits cache line use instead of queuing > - * objects in per cpu and per node lists. > - * > - * The allocator synchronizes using per slab locks or atomic operations > - * and only uses a centralized lock to manage a pool of partial slabs. > - * > - * (C) 2007 SGI, Christoph Lameter > - * (C) 2011 Linux Foundation, Christoph Lameter > - */ > - > -#include <linux/mm.h> > -#include <linux/swap.h> /* struct reclaim_state */ > -#include <linux/module.h> > -#include <linux/bit_spinlock.h> > -#include <linux/interrupt.h> > -#include <linux/swab.h> > -#include <linux/bitops.h> > -#include <linux/slab.h> > -#include "slab.h" > -#include <linux/proc_fs.h> > -#include <linux/seq_file.h> > -#include <linux/kasan.h> > -#include <linux/kmsan.h> > -#include <linux/cpu.h> > -#include <linux/cpuset.h> > -#include <linux/mempolicy.h> > -#include <linux/ctype.h> > -#include <linux/stackdepot.h> > -#include <linux/debugobjects.h> > -#include <linux/kallsyms.h> > -#include <linux/kfence.h> > -#include <linux/memory.h> > -#include <linux/math64.h> > -#include <linux/fault-inject.h> > -#include <linux/stacktrace.h> > -#include <linux/prefetch.h> > -#include <linux/memcontrol.h> > -#include <linux/random.h> > -#include <kunit/test.h> > -#include <kunit/test-bug.h> > -#include <linux/sort.h> > - > -#include <linux/debugfs.h> > -#include <trace/events/kmem.h> > - > -#include "internal.h" > - > -/* > - * Lock order: > - * 1. slab_mutex (Global Mutex) > - * 2. node->list_lock (Spinlock) > - * 3. kmem_cache->cpu_slab->lock (Local lock) > - * 4. slab_lock(slab) (Only on some arches) > - * 5. object_map_lock (Only for debugging) > - * > - * slab_mutex > - * > - * The role of the slab_mutex is to protect the list of all the slabs > - * and to synchronize major metadata changes to slab cache structures. > - * Also synchronizes memory hotplug callbacks. > - * > - * slab_lock > - * > - * The slab_lock is a wrapper around the page lock, thus it is a bit > - * spinlock. > - * > - * The slab_lock is only used on arches that do not have the ability > - * to do a cmpxchg_double. It only protects: > - * > - * A. slab->freelist -> List of free objects in a slab > - * B. slab->inuse -> Number of objects in use > - * C. slab->objects -> Number of objects in slab > - * D. slab->frozen -> frozen state > - * > - * Frozen slabs > - * > - * If a slab is frozen then it is exempt from list management. It is not > - * on any list except per cpu partial list. The processor that froze the > - * slab is the one who can perform list operations on the slab. Other > - * processors may put objects onto the freelist but the processor that > - * froze the slab is the only one that can retrieve the objects from the > - * slab's freelist. > - * > - * list_lock > - * > - * The list_lock protects the partial and full list on each node and > - * the partial slab counter. If taken then no new slabs may be added or > - * removed from the lists nor make the number of partial slabs be modified. > - * (Note that the total number of slabs is an atomic value that may be > - * modified without taking the list lock). > - * > - * The list_lock is a centralized lock and thus we avoid taking it as > - * much as possible. As long as SLUB does not have to handle partial > - * slabs, operations can continue without any centralized lock. F.e. > - * allocating a long series of objects that fill up slabs does not require > - * the list lock. > - * > - * For debug caches, all allocations are forced to go through a list_lock > - * protected region to serialize against concurrent validation. > - * > - * cpu_slab->lock local lock > - * > - * This locks protect slowpath manipulation of all kmem_cache_cpu fields > - * except the stat counters. This is a percpu structure manipulated only by > - * the local cpu, so the lock protects against being preempted or interrupted > - * by an irq. Fast path operations rely on lockless operations instead. > - * > - * On PREEMPT_RT, the local lock neither disables interrupts nor preemption > - * which means the lockless fastpath cannot be used as it might interfere with > - * an in-progress slow path operations. In this case the local lock is always > - * taken but it still utilizes the freelist for the common operations. > - * > - * lockless fastpaths > - * > - * The fast path allocation (slab_alloc_node()) and freeing (do_slab_free()) > - * are fully lockless when satisfied from the percpu slab (and when > - * cmpxchg_double is possible to use, otherwise slab_lock is taken). > - * They also don't disable preemption or migration or irqs. They rely on > - * the transaction id (tid) field to detect being preempted or moved to > - * another cpu. > - * > - * irq, preemption, migration considerations > - * > - * Interrupts are disabled as part of list_lock or local_lock operations, or > - * around the slab_lock operation, in order to make the slab allocator safe > - * to use in the context of an irq. > - * > - * In addition, preemption (or migration on PREEMPT_RT) is disabled in the > - * allocation slowpath, bulk allocation, and put_cpu_partial(), so that the > - * local cpu doesn't change in the process and e.g. the kmem_cache_cpu pointer > - * doesn't have to be revalidated in each section protected by the local lock. > - * > - * SLUB assigns one slab for allocation to each processor. > - * Allocations only occur from these slabs called cpu slabs. > - * > - * Slabs with free elements are kept on a partial list and during regular > - * operations no list for full slabs is used. If an object in a full slab is > - * freed then the slab will show up again on the partial lists. > - * We track full slabs for debugging purposes though because otherwise we > - * cannot scan all objects. > - * > - * Slabs are freed when they become empty. Teardown and setup is > - * minimal so we rely on the page allocators per cpu caches for > - * fast frees and allocs. > - * > - * slab->frozen The slab is frozen and exempt from list processing. > - * This means that the slab is dedicated to a purpose > - * such as satisfying allocations for a specific > - * processor. Objects may be freed in the slab while > - * it is frozen but slab_free will then skip the usual > - * list operations. It is up to the processor holding > - * the slab to integrate the slab into the slab lists > - * when the slab is no longer needed. > - * > - * One use of this flag is to mark slabs that are > - * used for allocations. Then such a slab becomes a cpu > - * slab. The cpu slab may be equipped with an additional > - * freelist that allows lockless access to > - * free objects in addition to the regular freelist > - * that requires the slab lock. > - * > - * SLAB_DEBUG_FLAGS Slab requires special handling due to debug > - * options set. This moves slab handling out of > - * the fast path and disables lockless freelists. > - */ > - > -/* > - * We could simply use migrate_disable()/enable() but as long as it's a > - * function call even on !PREEMPT_RT, use inline preempt_disable() there. > - */ > -#ifndef CONFIG_PREEMPT_RT > -#define slub_get_cpu_ptr(var) get_cpu_ptr(var) > -#define slub_put_cpu_ptr(var) put_cpu_ptr(var) > -#define USE_LOCKLESS_FAST_PATH() (true) > -#else > -#define slub_get_cpu_ptr(var) \ > -({ \ > - migrate_disable(); \ > - this_cpu_ptr(var); \ > -}) > -#define slub_put_cpu_ptr(var) \ > -do { \ > - (void)(var); \ > - migrate_enable(); \ > -} while (0) > -#define USE_LOCKLESS_FAST_PATH() (false) > -#endif > - > -#ifndef CONFIG_SLUB_TINY > -#define __fastpath_inline __always_inline > -#else > -#define __fastpath_inline > -#endif > - > -#ifdef CONFIG_SLUB_DEBUG > -#ifdef CONFIG_SLUB_DEBUG_ON > -DEFINE_STATIC_KEY_TRUE(slub_debug_enabled); > -#else > -DEFINE_STATIC_KEY_FALSE(slub_debug_enabled); > -#endif > -#endif /* CONFIG_SLUB_DEBUG */ > - > -/* Structure holding parameters for get_partial() call chain */ > -struct partial_context { > - struct slab **slab; > - gfp_t flags; > - unsigned int orig_size; > -}; > - > -static inline bool kmem_cache_debug(struct kmem_cache *s) > -{ > - return kmem_cache_debug_flags(s, SLAB_DEBUG_FLAGS); > -} > - > -static inline bool slub_debug_orig_size(struct kmem_cache *s) > -{ > - return (kmem_cache_debug_flags(s, SLAB_STORE_USER) && > - (s->flags & SLAB_KMALLOC)); > -} > - > -void *fixup_red_left(struct kmem_cache *s, void *p) > -{ > - if (kmem_cache_debug_flags(s, SLAB_RED_ZONE)) > - p += s->red_left_pad; > - > - return p; > -} > - > -static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s) > -{ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - return !kmem_cache_debug(s); > -#else > - return false; > -#endif > -} > - > -/* > - * Issues still to be resolved: > - * > - * - Support PAGE_ALLOC_DEBUG. Should be easy to do. > - * > - * - Variable sizing of the per node arrays > - */ > - > -/* Enable to log cmpxchg failures */ > -#undef SLUB_DEBUG_CMPXCHG > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Minimum number of partial slabs. These will be left on the partial > - * lists even if they are empty. kmem_cache_shrink may reclaim them. > - */ > -#define MIN_PARTIAL 5 > - > -/* > - * Maximum number of desirable partial slabs. > - * The existence of more partial slabs makes kmem_cache_shrink > - * sort the partial list by the number of objects in use. > - */ > -#define MAX_PARTIAL 10 > -#else > -#define MIN_PARTIAL 0 > -#define MAX_PARTIAL 0 > -#endif > - > -#define DEBUG_DEFAULT_FLAGS (SLAB_CONSISTENCY_CHECKS | SLAB_RED_ZONE | \ > - SLAB_POISON | SLAB_STORE_USER) > - > -/* > - * These debug flags cannot use CMPXCHG because there might be consistency > - * issues when checking or reading debug information > - */ > -#define SLAB_NO_CMPXCHG (SLAB_CONSISTENCY_CHECKS | SLAB_STORE_USER | \ > - SLAB_TRACE) > - > - > -/* > - * Debugging flags that require metadata to be stored in the slab. These get > - * disabled when slub_debug=O is used and a cache's min order increases with > - * metadata. > - */ > -#define DEBUG_METADATA_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) > - > -#define OO_SHIFT 16 > -#define OO_MASK ((1 << OO_SHIFT) - 1) > -#define MAX_OBJS_PER_PAGE 32767 /* since slab.objects is u15 */ > - > -/* Internal SLUB flags */ > -/* Poison object */ > -#define __OBJECT_POISON ((slab_flags_t __force)0x80000000U) > -/* Use cmpxchg_double */ > -#define __CMPXCHG_DOUBLE ((slab_flags_t __force)0x40000000U) > - > -/* > - * Tracking user of a slab. > - */ > -#define TRACK_ADDRS_COUNT 16 > -struct track { > - unsigned long addr; /* Called from address */ > -#ifdef CONFIG_STACKDEPOT > - depot_stack_handle_t handle; > -#endif > - int cpu; /* Was running on cpu */ > - int pid; /* Pid context */ > - unsigned long when; /* When did the operation occur */ > -}; > - > -enum track_item { TRACK_ALLOC, TRACK_FREE }; > - > -#ifdef SLAB_SUPPORTS_SYSFS > -static int sysfs_slab_add(struct kmem_cache *); > -static int sysfs_slab_alias(struct kmem_cache *, const char *); > -#else > -static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; } > -static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) > - { return 0; } > -#endif > - > -#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) > -static void debugfs_slab_add(struct kmem_cache *); > -#else > -static inline void debugfs_slab_add(struct kmem_cache *s) { } > -#endif > - > -static inline void stat(const struct kmem_cache *s, enum stat_item si) > -{ > -#ifdef CONFIG_SLUB_STATS > - /* > - * The rmw is racy on a preemptible kernel but this is acceptable, so > - * avoid this_cpu_add()'s irq-disable overhead. > - */ > - raw_cpu_inc(s->cpu_slab->stat[si]); > -#endif > -} > - > -/* > - * Tracks for which NUMA nodes we have kmem_cache_nodes allocated. > - * Corresponds to node_state[N_NORMAL_MEMORY], but can temporarily > - * differ during memory hotplug/hotremove operations. > - * Protected by slab_mutex. > - */ > -static nodemask_t slab_nodes; > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Workqueue used for flush_cpu_slab(). > - */ > -static struct workqueue_struct *flushwq; > -#endif > - > -/******************************************************************** > - * Core slab cache functions > - *******************************************************************/ > - > -/* > - * Returns freelist pointer (ptr). With hardening, this is obfuscated > - * with an XOR of the address where the pointer is held and a per-cache > - * random number. > - */ > -static inline void *freelist_ptr(const struct kmem_cache *s, void *ptr, > - unsigned long ptr_addr) > -{ > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - /* > - * When CONFIG_KASAN_SW/HW_TAGS is enabled, ptr_addr might be tagged. > - * Normally, this doesn't cause any issues, as both set_freepointer() > - * and get_freepointer() are called with a pointer with the same tag. > - * However, there are some issues with CONFIG_SLUB_DEBUG code. For > - * example, when __free_slub() iterates over objects in a cache, it > - * passes untagged pointers to check_object(). check_object() in turns > - * calls get_freepointer() with an untagged pointer, which causes the > - * freepointer to be restored incorrectly. > - */ > - return (void *)((unsigned long)ptr ^ s->random ^ > - swab((unsigned long)kasan_reset_tag((void *)ptr_addr))); > -#else > - return ptr; > -#endif > -} > - > -/* Returns the freelist pointer recorded at location ptr_addr. */ > -static inline void *freelist_dereference(const struct kmem_cache *s, > - void *ptr_addr) > -{ > - return freelist_ptr(s, (void *)*(unsigned long *)(ptr_addr), > - (unsigned long)ptr_addr); > -} > - > -static inline void *get_freepointer(struct kmem_cache *s, void *object) > -{ > - object = kasan_reset_tag(object); > - return freelist_dereference(s, object + s->offset); > -} > - > -#ifndef CONFIG_SLUB_TINY > -static void prefetch_freepointer(const struct kmem_cache *s, void *object) > -{ > - prefetchw(object + s->offset); > -} > -#endif > - > -/* > - * When running under KMSAN, get_freepointer_safe() may return an uninitialized > - * pointer value in the case the current thread loses the race for the next > - * memory chunk in the freelist. In that case this_cpu_cmpxchg_double() in > - * slab_alloc_node() will fail, so the uninitialized value won't be used, but > - * KMSAN will still check all arguments of cmpxchg because of imperfect > - * handling of inline assembly. > - * To work around this problem, we apply __no_kmsan_checks to ensure that > - * get_freepointer_safe() returns initialized memory. > - */ > -__no_kmsan_checks > -static inline void *get_freepointer_safe(struct kmem_cache *s, void *object) > -{ > - unsigned long freepointer_addr; > - void *p; > - > - if (!debug_pagealloc_enabled_static()) > - return get_freepointer(s, object); > - > - object = kasan_reset_tag(object); > - freepointer_addr = (unsigned long)object + s->offset; > - copy_from_kernel_nofault(&p, (void **)freepointer_addr, sizeof(p)); > - return freelist_ptr(s, p, freepointer_addr); > -} > - > -static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) > -{ > - unsigned long freeptr_addr = (unsigned long)object + s->offset; > - > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - BUG_ON(object == fp); /* naive detection of double free or corruption */ > -#endif > - > - freeptr_addr = (unsigned long)kasan_reset_tag((void *)freeptr_addr); > - *(void **)freeptr_addr = freelist_ptr(s, fp, freeptr_addr); > -} > - > -/* Loop over all objects in a slab */ > -#define for_each_object(__p, __s, __addr, __objects) \ > - for (__p = fixup_red_left(__s, __addr); \ > - __p < (__addr) + (__objects) * (__s)->size; \ > - __p += (__s)->size) > - > -static inline unsigned int order_objects(unsigned int order, unsigned int size) > -{ > - return ((unsigned int)PAGE_SIZE << order) / size; > -} > - > -static inline struct kmem_cache_order_objects oo_make(unsigned int order, > - unsigned int size) > -{ > - struct kmem_cache_order_objects x = { > - (order << OO_SHIFT) + order_objects(order, size) > - }; > - > - return x; > -} > - > -static inline unsigned int oo_order(struct kmem_cache_order_objects x) > -{ > - return x.x >> OO_SHIFT; > -} > - > -static inline unsigned int oo_objects(struct kmem_cache_order_objects x) > -{ > - return x.x & OO_MASK; > -} > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -static void slub_set_cpu_partial(struct kmem_cache *s, unsigned int nr_objects) > -{ > - unsigned int nr_slabs; > - > - s->cpu_partial = nr_objects; > - > - /* > - * We take the number of objects but actually limit the number of > - * slabs on the per cpu partial list, in order to limit excessive > - * growth of the list. For simplicity we assume that the slabs will > - * be half-full. > - */ > - nr_slabs = DIV_ROUND_UP(nr_objects * 2, oo_objects(s->oo)); > - s->cpu_partial_slabs = nr_slabs; > -} > -#else > -static inline void > -slub_set_cpu_partial(struct kmem_cache *s, unsigned int nr_objects) > -{ > -} > -#endif /* CONFIG_SLUB_CPU_PARTIAL */ > - > -/* > - * Per slab locking using the pagelock > - */ > -static __always_inline void slab_lock(struct slab *slab) > -{ > - struct page *page = slab_page(slab); > - > - VM_BUG_ON_PAGE(PageTail(page), page); > - bit_spin_lock(PG_locked, &page->flags); > -} > - > -static __always_inline void slab_unlock(struct slab *slab) > -{ > - struct page *page = slab_page(slab); > - > - VM_BUG_ON_PAGE(PageTail(page), page); > - __bit_spin_unlock(PG_locked, &page->flags); > -} > - > -/* > - * Interrupts must be disabled (for the fallback code to work right), typically > - * by an _irqsave() lock variant. On PREEMPT_RT the preempt_disable(), which is > - * part of bit_spin_lock(), is sufficient because the policy is not to allow any > - * allocation/ free operation in hardirq context. Therefore nothing can > - * interrupt the operation. > - */ > -static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab, > - void *freelist_old, unsigned long counters_old, > - void *freelist_new, unsigned long counters_new, > - const char *n) > -{ > - if (USE_LOCKLESS_FAST_PATH()) > - lockdep_assert_irqs_disabled(); > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ > - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) > - if (s->flags & __CMPXCHG_DOUBLE) { > - if (cmpxchg_double(&slab->freelist, &slab->counters, > - freelist_old, counters_old, > - freelist_new, counters_new)) > - return true; > - } else > -#endif > - { > - slab_lock(slab); > - if (slab->freelist == freelist_old && > - slab->counters == counters_old) { > - slab->freelist = freelist_new; > - slab->counters = counters_new; > - slab_unlock(slab); > - return true; > - } > - slab_unlock(slab); > - } > - > - cpu_relax(); > - stat(s, CMPXCHG_DOUBLE_FAIL); > - > -#ifdef SLUB_DEBUG_CMPXCHG > - pr_info("%s %s: cmpxchg double redo ", n, s->name); > -#endif > - > - return false; > -} > - > -static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab, > - void *freelist_old, unsigned long counters_old, > - void *freelist_new, unsigned long counters_new, > - const char *n) > -{ > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ > - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) > - if (s->flags & __CMPXCHG_DOUBLE) { > - if (cmpxchg_double(&slab->freelist, &slab->counters, > - freelist_old, counters_old, > - freelist_new, counters_new)) > - return true; > - } else > -#endif > - { > - unsigned long flags; > - > - local_irq_save(flags); > - slab_lock(slab); > - if (slab->freelist == freelist_old && > - slab->counters == counters_old) { > - slab->freelist = freelist_new; > - slab->counters = counters_new; > - slab_unlock(slab); > - local_irq_restore(flags); > - return true; > - } > - slab_unlock(slab); > - local_irq_restore(flags); > - } > - > - cpu_relax(); > - stat(s, CMPXCHG_DOUBLE_FAIL); > - > -#ifdef SLUB_DEBUG_CMPXCHG > - pr_info("%s %s: cmpxchg double redo ", n, s->name); > -#endif > - > - return false; > -} > - > -#ifdef CONFIG_SLUB_DEBUG > -static unsigned long object_map[BITS_TO_LONGS(MAX_OBJS_PER_PAGE)]; > -static DEFINE_SPINLOCK(object_map_lock); > - > -static void __fill_map(unsigned long *obj_map, struct kmem_cache *s, > - struct slab *slab) > -{ > - void *addr = slab_address(slab); > - void *p; > - > - bitmap_zero(obj_map, slab->objects); > - > - for (p = slab->freelist; p; p = get_freepointer(s, p)) > - set_bit(__obj_to_index(s, addr, p), obj_map); > -} > - > -#if IS_ENABLED(CONFIG_KUNIT) > -static bool slab_add_kunit_errors(void) > -{ > - struct kunit_resource *resource; > - > - if (!kunit_get_current_test()) > - return false; > - > - resource = kunit_find_named_resource(current->kunit_test, "slab_errors"); > - if (!resource) > - return false; > - > - (*(int *)resource->data)++; > - kunit_put_resource(resource); > - return true; > -} > -#else > -static inline bool slab_add_kunit_errors(void) { return false; } > -#endif > - > -static inline unsigned int size_from_object(struct kmem_cache *s) > -{ > - if (s->flags & SLAB_RED_ZONE) > - return s->size - s->red_left_pad; > - > - return s->size; > -} > - > -static inline void *restore_red_left(struct kmem_cache *s, void *p) > -{ > - if (s->flags & SLAB_RED_ZONE) > - p -= s->red_left_pad; > - > - return p; > -} > - > -/* > - * Debug settings: > - */ > -#if defined(CONFIG_SLUB_DEBUG_ON) > -static slab_flags_t slub_debug = DEBUG_DEFAULT_FLAGS; > -#else > -static slab_flags_t slub_debug; > -#endif > - > -static char *slub_debug_string; > -static int disable_higher_order_debug; > - > -/* > - * slub is about to manipulate internal object metadata. This memory lies > - * outside the range of the allocated object, so accessing it would normally > - * be reported by kasan as a bounds error. metadata_access_enable() is used > - * to tell kasan that these accesses are OK. > - */ > -static inline void metadata_access_enable(void) > -{ > - kasan_disable_current(); > -} > - > -static inline void metadata_access_disable(void) > -{ > - kasan_enable_current(); > -} > - > -/* > - * Object debugging > - */ > - > -/* Verify that a pointer has an address that is valid within a slab page */ > -static inline int check_valid_pointer(struct kmem_cache *s, > - struct slab *slab, void *object) > -{ > - void *base; > - > - if (!object) > - return 1; > - > - base = slab_address(slab); > - object = kasan_reset_tag(object); > - object = restore_red_left(s, object); > - if (object < base || object >= base + slab->objects * s->size || > - (object - base) % s->size) { > - return 0; > - } > - > - return 1; > -} > - > -static void print_section(char *level, char *text, u8 *addr, > - unsigned int length) > -{ > - metadata_access_enable(); > - print_hex_dump(level, text, DUMP_PREFIX_ADDRESS, > - 16, 1, kasan_reset_tag((void *)addr), length, 1); > - metadata_access_disable(); > -} > - > -/* > - * See comment in calculate_sizes(). > - */ > -static inline bool freeptr_outside_object(struct kmem_cache *s) > -{ > - return s->offset >= s->inuse; > -} > - > -/* > - * Return offset of the end of info block which is inuse + free pointer if > - * not overlapping with object. > - */ > -static inline unsigned int get_info_end(struct kmem_cache *s) > -{ > - if (freeptr_outside_object(s)) > - return s->inuse + sizeof(void *); > - else > - return s->inuse; > -} > - > -static struct track *get_track(struct kmem_cache *s, void *object, > - enum track_item alloc) > -{ > - struct track *p; > - > - p = object + get_info_end(s); > - > - return kasan_reset_tag(p + alloc); > -} > - > -#ifdef CONFIG_STACKDEPOT > -static noinline depot_stack_handle_t set_track_prepare(void) > -{ > - depot_stack_handle_t handle; > - unsigned long entries[TRACK_ADDRS_COUNT]; > - unsigned int nr_entries; > - > - nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 3); > - handle = stack_depot_save(entries, nr_entries, GFP_NOWAIT); > - > - return handle; > -} > -#else > -static inline depot_stack_handle_t set_track_prepare(void) > -{ > - return 0; > -} > -#endif > - > -static void set_track_update(struct kmem_cache *s, void *object, > - enum track_item alloc, unsigned long addr, > - depot_stack_handle_t handle) > -{ > - struct track *p = get_track(s, object, alloc); > - > -#ifdef CONFIG_STACKDEPOT > - p->handle = handle; > -#endif > - p->addr = addr; > - p->cpu = smp_processor_id(); > - p->pid = current->pid; > - p->when = jiffies; > -} > - > -static __always_inline void set_track(struct kmem_cache *s, void *object, > - enum track_item alloc, unsigned long addr) > -{ > - depot_stack_handle_t handle = set_track_prepare(); > - > - set_track_update(s, object, alloc, addr, handle); > -} > - > -static void init_tracking(struct kmem_cache *s, void *object) > -{ > - struct track *p; > - > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - p = get_track(s, object, TRACK_ALLOC); > - memset(p, 0, 2*sizeof(struct track)); > -} > - > -static void print_track(const char *s, struct track *t, unsigned long pr_time) > -{ > - depot_stack_handle_t handle __maybe_unused; > - > - if (!t->addr) > - return; > - > - pr_err("%s in %pS age=%lu cpu=%u pid=%d\n", > - s, (void *)t->addr, pr_time - t->when, t->cpu, t->pid); > -#ifdef CONFIG_STACKDEPOT > - handle = READ_ONCE(t->handle); > - if (handle) > - stack_depot_print(handle); > - else > - pr_err("object allocation/free stack trace missing\n"); > -#endif > -} > - > -void print_tracking(struct kmem_cache *s, void *object) > -{ > - unsigned long pr_time = jiffies; > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - print_track("Allocated", get_track(s, object, TRACK_ALLOC), pr_time); > - print_track("Freed", get_track(s, object, TRACK_FREE), pr_time); > -} > - > -static void print_slab_info(const struct slab *slab) > -{ > - struct folio *folio = (struct folio *)slab_folio(slab); > - > - pr_err("Slab 0x%p objects=%u used=%u fp=0x%p flags=%pGp\n", > - slab, slab->objects, slab->inuse, slab->freelist, > - folio_flags(folio, 0)); > -} > - > -/* > - * kmalloc caches has fixed sizes (mostly power of 2), and kmalloc() API > - * family will round up the real request size to these fixed ones, so > - * there could be an extra area than what is requested. Save the original > - * request size in the meta data area, for better debug and sanity check. > - */ > -static inline void set_orig_size(struct kmem_cache *s, > - void *object, unsigned int orig_size) > -{ > - void *p = kasan_reset_tag(object); > - > - if (!slub_debug_orig_size(s)) > - return; > - > -#ifdef CONFIG_KASAN_GENERIC > - /* > - * KASAN could save its free meta data in object's data area at > - * offset 0, if the size is larger than 'orig_size', it will > - * overlap the data redzone in [orig_size+1, object_size], and > - * the check should be skipped. > - */ > - if (kasan_metadata_size(s, true) > orig_size) > - orig_size = s->object_size; > -#endif > - > - p += get_info_end(s); > - p += sizeof(struct track) * 2; > - > - *(unsigned int *)p = orig_size; > -} > - > -static inline unsigned int get_orig_size(struct kmem_cache *s, void *object) > -{ > - void *p = kasan_reset_tag(object); > - > - if (!slub_debug_orig_size(s)) > - return s->object_size; > - > - p += get_info_end(s); > - p += sizeof(struct track) * 2; > - > - return *(unsigned int *)p; > -} > - > -void skip_orig_size_check(struct kmem_cache *s, const void *object) > -{ > - set_orig_size(s, (void *)object, s->object_size); > -} > - > -static void slab_bug(struct kmem_cache *s, char *fmt, ...) > -{ > - struct va_format vaf; > - va_list args; > - > - va_start(args, fmt); > - vaf.fmt = fmt; > - vaf.va = &args; > - pr_err("=============================================================================\n"); > - pr_err("BUG %s (%s): %pV\n", s->name, print_tainted(), &vaf); > - pr_err("-----------------------------------------------------------------------------\n\n"); > - va_end(args); > -} > - > -__printf(2, 3) > -static void slab_fix(struct kmem_cache *s, char *fmt, ...) > -{ > - struct va_format vaf; > - va_list args; > - > - if (slab_add_kunit_errors()) > - return; > - > - va_start(args, fmt); > - vaf.fmt = fmt; > - vaf.va = &args; > - pr_err("FIX %s: %pV\n", s->name, &vaf); > - va_end(args); > -} > - > -static void print_trailer(struct kmem_cache *s, struct slab *slab, u8 *p) > -{ > - unsigned int off; /* Offset of last byte */ > - u8 *addr = slab_address(slab); > - > - print_tracking(s, p); > - > - print_slab_info(slab); > - > - pr_err("Object 0x%p @offset=%tu fp=0x%p\n\n", > - p, p - addr, get_freepointer(s, p)); > - > - if (s->flags & SLAB_RED_ZONE) > - print_section(KERN_ERR, "Redzone ", p - s->red_left_pad, > - s->red_left_pad); > - else if (p > addr + 16) > - print_section(KERN_ERR, "Bytes b4 ", p - 16, 16); > - > - print_section(KERN_ERR, "Object ", p, > - min_t(unsigned int, s->object_size, PAGE_SIZE)); > - if (s->flags & SLAB_RED_ZONE) > - print_section(KERN_ERR, "Redzone ", p + s->object_size, > - s->inuse - s->object_size); > - > - off = get_info_end(s); > - > - if (s->flags & SLAB_STORE_USER) > - off += 2 * sizeof(struct track); > - > - if (slub_debug_orig_size(s)) > - off += sizeof(unsigned int); > - > - off += kasan_metadata_size(s, false); > - > - if (off != size_from_object(s)) > - /* Beginning of the filler is the free pointer */ > - print_section(KERN_ERR, "Padding ", p + off, > - size_from_object(s) - off); > - > - dump_stack(); > -} > - > -static void object_err(struct kmem_cache *s, struct slab *slab, > - u8 *object, char *reason) > -{ > - if (slab_add_kunit_errors()) > - return; > - > - slab_bug(s, "%s", reason); > - print_trailer(s, slab, object); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > - > -static bool freelist_corrupted(struct kmem_cache *s, struct slab *slab, > - void **freelist, void *nextfree) > -{ > - if ((s->flags & SLAB_CONSISTENCY_CHECKS) && > - !check_valid_pointer(s, slab, nextfree) && freelist) { > - object_err(s, slab, *freelist, "Freechain corrupt"); > - *freelist = NULL; > - slab_fix(s, "Isolate corrupted freechain"); > - return true; > - } > - > - return false; > -} > - > -static __printf(3, 4) void slab_err(struct kmem_cache *s, struct slab *slab, > - const char *fmt, ...) > -{ > - va_list args; > - char buf[100]; > - > - if (slab_add_kunit_errors()) > - return; > - > - va_start(args, fmt); > - vsnprintf(buf, sizeof(buf), fmt, args); > - va_end(args); > - slab_bug(s, "%s", buf); > - print_slab_info(slab); > - dump_stack(); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > - > -static void init_object(struct kmem_cache *s, void *object, u8 val) > -{ > - u8 *p = kasan_reset_tag(object); > - unsigned int poison_size = s->object_size; > - > - if (s->flags & SLAB_RED_ZONE) { > - memset(p - s->red_left_pad, val, s->red_left_pad); > - > - if (slub_debug_orig_size(s) && val == SLUB_RED_ACTIVE) { > - /* > - * Redzone the extra allocated space by kmalloc than > - * requested, and the poison size will be limited to > - * the original request size accordingly. > - */ > - poison_size = get_orig_size(s, object); > - } > - } > - > - if (s->flags & __OBJECT_POISON) { > - memset(p, POISON_FREE, poison_size - 1); > - p[poison_size - 1] = POISON_END; > - } > - > - if (s->flags & SLAB_RED_ZONE) > - memset(p + poison_size, val, s->inuse - poison_size); > -} > - > -static void restore_bytes(struct kmem_cache *s, char *message, u8 data, > - void *from, void *to) > -{ > - slab_fix(s, "Restoring %s 0x%p-0x%p=0x%x", message, from, to - 1, data); > - memset(from, data, to - from); > -} > - > -static int check_bytes_and_report(struct kmem_cache *s, struct slab *slab, > - u8 *object, char *what, > - u8 *start, unsigned int value, unsigned int bytes) > -{ > - u8 *fault; > - u8 *end; > - u8 *addr = slab_address(slab); > - > - metadata_access_enable(); > - fault = memchr_inv(kasan_reset_tag(start), value, bytes); > - metadata_access_disable(); > - if (!fault) > - return 1; > - > - end = start + bytes; > - while (end > fault && end[-1] == value) > - end--; > - > - if (slab_add_kunit_errors()) > - goto skip_bug_print; > - > - slab_bug(s, "%s overwritten", what); > - pr_err("0x%p-0x%p @offset=%tu. First byte 0x%x instead of 0x%x\n", > - fault, end - 1, fault - addr, > - fault[0], value); > - print_trailer(s, slab, object); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > - > -skip_bug_print: > - restore_bytes(s, what, value, fault, end); > - return 0; > -} > - > -/* > - * Object layout: > - * > - * object address > - * Bytes of the object to be managed. > - * If the freepointer may overlay the object then the free > - * pointer is at the middle of the object. > - * > - * Poisoning uses 0x6b (POISON_FREE) and the last byte is > - * 0xa5 (POISON_END) > - * > - * object + s->object_size > - * Padding to reach word boundary. This is also used for Redzoning. > - * Padding is extended by another word if Redzoning is enabled and > - * object_size == inuse. > - * > - * We fill with 0xbb (RED_INACTIVE) for inactive objects and with > - * 0xcc (RED_ACTIVE) for objects in use. > - * > - * object + s->inuse > - * Meta data starts here. > - * > - * A. Free pointer (if we cannot overwrite object on free) > - * B. Tracking data for SLAB_STORE_USER > - * C. Original request size for kmalloc object (SLAB_STORE_USER enabled) > - * D. Padding to reach required alignment boundary or at minimum > - * one word if debugging is on to be able to detect writes > - * before the word boundary. > - * > - * Padding is done using 0x5a (POISON_INUSE) > - * > - * object + s->size > - * Nothing is used beyond s->size. > - * > - * If slabcaches are merged then the object_size and inuse boundaries are mostly > - * ignored. And therefore no slab options that rely on these boundaries > - * may be used with merged slabcaches. > - */ > - > -static int check_pad_bytes(struct kmem_cache *s, struct slab *slab, u8 *p) > -{ > - unsigned long off = get_info_end(s); /* The end of info */ > - > - if (s->flags & SLAB_STORE_USER) { > - /* We also have user information there */ > - off += 2 * sizeof(struct track); > - > - if (s->flags & SLAB_KMALLOC) > - off += sizeof(unsigned int); > - } > - > - off += kasan_metadata_size(s, false); > - > - if (size_from_object(s) == off) > - return 1; > - > - return check_bytes_and_report(s, slab, p, "Object padding", > - p + off, POISON_INUSE, size_from_object(s) - off); > -} > - > -/* Check the pad bytes at the end of a slab page */ > -static void slab_pad_check(struct kmem_cache *s, struct slab *slab) > -{ > - u8 *start; > - u8 *fault; > - u8 *end; > - u8 *pad; > - int length; > - int remainder; > - > - if (!(s->flags & SLAB_POISON)) > - return; > - > - start = slab_address(slab); > - length = slab_size(slab); > - end = start + length; > - remainder = length % s->size; > - if (!remainder) > - return; > - > - pad = end - remainder; > - metadata_access_enable(); > - fault = memchr_inv(kasan_reset_tag(pad), POISON_INUSE, remainder); > - metadata_access_disable(); > - if (!fault) > - return; > - while (end > fault && end[-1] == POISON_INUSE) > - end--; > - > - slab_err(s, slab, "Padding overwritten. 0x%p-0x%p @offset=%tu", > - fault, end - 1, fault - start); > - print_section(KERN_ERR, "Padding ", pad, remainder); > - > - restore_bytes(s, "slab padding", POISON_INUSE, fault, end); > -} > - > -static int check_object(struct kmem_cache *s, struct slab *slab, > - void *object, u8 val) > -{ > - u8 *p = object; > - u8 *endobject = object + s->object_size; > - unsigned int orig_size; > - > - if (s->flags & SLAB_RED_ZONE) { > - if (!check_bytes_and_report(s, slab, object, "Left Redzone", > - object - s->red_left_pad, val, s->red_left_pad)) > - return 0; > - > - if (!check_bytes_and_report(s, slab, object, "Right Redzone", > - endobject, val, s->inuse - s->object_size)) > - return 0; > - > - if (slub_debug_orig_size(s) && val == SLUB_RED_ACTIVE) { > - orig_size = get_orig_size(s, object); > - > - if (s->object_size > orig_size && > - !check_bytes_and_report(s, slab, object, > - "kmalloc Redzone", p + orig_size, > - val, s->object_size - orig_size)) { > - return 0; > - } > - } > - } else { > - if ((s->flags & SLAB_POISON) && s->object_size < s->inuse) { > - check_bytes_and_report(s, slab, p, "Alignment padding", > - endobject, POISON_INUSE, > - s->inuse - s->object_size); > - } > - } > - > - if (s->flags & SLAB_POISON) { > - if (val != SLUB_RED_ACTIVE && (s->flags & __OBJECT_POISON) && > - (!check_bytes_and_report(s, slab, p, "Poison", p, > - POISON_FREE, s->object_size - 1) || > - !check_bytes_and_report(s, slab, p, "End Poison", > - p + s->object_size - 1, POISON_END, 1))) > - return 0; > - /* > - * check_pad_bytes cleans up on its own. > - */ > - check_pad_bytes(s, slab, p); > - } > - > - if (!freeptr_outside_object(s) && val == SLUB_RED_ACTIVE) > - /* > - * Object and freepointer overlap. Cannot check > - * freepointer while object is allocated. > - */ > - return 1; > - > - /* Check free pointer validity */ > - if (!check_valid_pointer(s, slab, get_freepointer(s, p))) { > - object_err(s, slab, p, "Freepointer corrupt"); > - /* > - * No choice but to zap it and thus lose the remainder > - * of the free objects in this slab. May cause > - * another error because the object count is now wrong. > - */ > - set_freepointer(s, p, NULL); > - return 0; > - } > - return 1; > -} > - > -static int check_slab(struct kmem_cache *s, struct slab *slab) > -{ > - int maxobj; > - > - if (!folio_test_slab(slab_folio(slab))) { > - slab_err(s, slab, "Not a valid slab page"); > - return 0; > - } > - > - maxobj = order_objects(slab_order(slab), s->size); > - if (slab->objects > maxobj) { > - slab_err(s, slab, "objects %u > max %u", > - slab->objects, maxobj); > - return 0; > - } > - if (slab->inuse > slab->objects) { > - slab_err(s, slab, "inuse %u > max %u", > - slab->inuse, slab->objects); > - return 0; > - } > - /* Slab_pad_check fixes things up after itself */ > - slab_pad_check(s, slab); > - return 1; > -} > - > -/* > - * Determine if a certain object in a slab is on the freelist. Must hold the > - * slab lock to guarantee that the chains are in a consistent state. > - */ > -static int on_freelist(struct kmem_cache *s, struct slab *slab, void *search) > -{ > - int nr = 0; > - void *fp; > - void *object = NULL; > - int max_objects; > - > - fp = slab->freelist; > - while (fp && nr <= slab->objects) { > - if (fp == search) > - return 1; > - if (!check_valid_pointer(s, slab, fp)) { > - if (object) { > - object_err(s, slab, object, > - "Freechain corrupt"); > - set_freepointer(s, object, NULL); > - } else { > - slab_err(s, slab, "Freepointer corrupt"); > - slab->freelist = NULL; > - slab->inuse = slab->objects; > - slab_fix(s, "Freelist cleared"); > - return 0; > - } > - break; > - } > - object = fp; > - fp = get_freepointer(s, object); > - nr++; > - } > - > - max_objects = order_objects(slab_order(slab), s->size); > - if (max_objects > MAX_OBJS_PER_PAGE) > - max_objects = MAX_OBJS_PER_PAGE; > - > - if (slab->objects != max_objects) { > - slab_err(s, slab, "Wrong number of objects. Found %d but should be %d", > - slab->objects, max_objects); > - slab->objects = max_objects; > - slab_fix(s, "Number of objects adjusted"); > - } > - if (slab->inuse != slab->objects - nr) { > - slab_err(s, slab, "Wrong object count. Counter is %d but counted were %d", > - slab->inuse, slab->objects - nr); > - slab->inuse = slab->objects - nr; > - slab_fix(s, "Object count adjusted"); > - } > - return search == NULL; > -} > - > -static void trace(struct kmem_cache *s, struct slab *slab, void *object, > - int alloc) > -{ > - if (s->flags & SLAB_TRACE) { > - pr_info("TRACE %s %s 0x%p inuse=%d fp=0x%p\n", > - s->name, > - alloc ? "alloc" : "free", > - object, slab->inuse, > - slab->freelist); > - > - if (!alloc) > - print_section(KERN_INFO, "Object ", (void *)object, > - s->object_size); > - > - dump_stack(); > - } > -} > - > -/* > - * Tracking of fully allocated slabs for debugging purposes. > - */ > -static void add_full(struct kmem_cache *s, > - struct kmem_cache_node *n, struct slab *slab) > -{ > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - lockdep_assert_held(&n->list_lock); > - list_add(&slab->slab_list, &n->full); > -} > - > -static void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, struct slab *slab) > -{ > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - lockdep_assert_held(&n->list_lock); > - list_del(&slab->slab_list); > -} > - > -/* Tracking of the number of slabs for debugging purposes */ > -static inline unsigned long slabs_node(struct kmem_cache *s, int node) > -{ > - struct kmem_cache_node *n = get_node(s, node); > - > - return atomic_long_read(&n->nr_slabs); > -} > - > -static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) > -{ > - return atomic_long_read(&n->nr_slabs); > -} > - > -static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects) > -{ > - struct kmem_cache_node *n = get_node(s, node); > - > - /* > - * May be called early in order to allocate a slab for the > - * kmem_cache_node structure. Solve the chicken-egg > - * dilemma by deferring the increment of the count during > - * bootstrap (see early_kmem_cache_node_alloc). > - */ > - if (likely(n)) { > - atomic_long_inc(&n->nr_slabs); > - atomic_long_add(objects, &n->total_objects); > - } > -} > -static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects) > -{ > - struct kmem_cache_node *n = get_node(s, node); > - > - atomic_long_dec(&n->nr_slabs); > - atomic_long_sub(objects, &n->total_objects); > -} > - > -/* Object debug checks for alloc/free paths */ > -static void setup_object_debug(struct kmem_cache *s, void *object) > -{ > - if (!kmem_cache_debug_flags(s, SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON)) > - return; > - > - init_object(s, object, SLUB_RED_INACTIVE); > - init_tracking(s, object); > -} > - > -static > -void setup_slab_debug(struct kmem_cache *s, struct slab *slab, void *addr) > -{ > - if (!kmem_cache_debug_flags(s, SLAB_POISON)) > - return; > - > - metadata_access_enable(); > - memset(kasan_reset_tag(addr), POISON_INUSE, slab_size(slab)); > - metadata_access_disable(); > -} > - > -static inline int alloc_consistency_checks(struct kmem_cache *s, > - struct slab *slab, void *object) > -{ > - if (!check_slab(s, slab)) > - return 0; > - > - if (!check_valid_pointer(s, slab, object)) { > - object_err(s, slab, object, "Freelist Pointer check fails"); > - return 0; > - } > - > - if (!check_object(s, slab, object, SLUB_RED_INACTIVE)) > - return 0; > - > - return 1; > -} > - > -static noinline bool alloc_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *object, int orig_size) > -{ > - if (s->flags & SLAB_CONSISTENCY_CHECKS) { > - if (!alloc_consistency_checks(s, slab, object)) > - goto bad; > - } > - > - /* Success. Perform special debug activities for allocs */ > - trace(s, slab, object, 1); > - set_orig_size(s, object, orig_size); > - init_object(s, object, SLUB_RED_ACTIVE); > - return true; > - > -bad: > - if (folio_test_slab(slab_folio(slab))) { > - /* > - * If this is a slab page then lets do the best we can > - * to avoid issues in the future. Marking all objects > - * as used avoids touching the remaining objects. > - */ > - slab_fix(s, "Marking all objects used"); > - slab->inuse = slab->objects; > - slab->freelist = NULL; > - } > - return false; > -} > - > -static inline int free_consistency_checks(struct kmem_cache *s, > - struct slab *slab, void *object, unsigned long addr) > -{ > - if (!check_valid_pointer(s, slab, object)) { > - slab_err(s, slab, "Invalid object pointer 0x%p", object); > - return 0; > - } > - > - if (on_freelist(s, slab, object)) { > - object_err(s, slab, object, "Object already free"); > - return 0; > - } > - > - if (!check_object(s, slab, object, SLUB_RED_ACTIVE)) > - return 0; > - > - if (unlikely(s != slab->slab_cache)) { > - if (!folio_test_slab(slab_folio(slab))) { > - slab_err(s, slab, "Attempt to free object(0x%p) outside of slab", > - object); > - } else if (!slab->slab_cache) { > - pr_err("SLUB <none>: no slab for object 0x%p.\n", > - object); > - dump_stack(); > - } else > - object_err(s, slab, object, > - "page slab pointer corrupt."); > - return 0; > - } > - return 1; > -} > - > -/* > - * Parse a block of slub_debug options. Blocks are delimited by ';' > - * > - * @str: start of block > - * @flags: returns parsed flags, or DEBUG_DEFAULT_FLAGS if none specified > - * @slabs: return start of list of slabs, or NULL when there's no list > - * @init: assume this is initial parsing and not per-kmem-create parsing > - * > - * returns the start of next block if there's any, or NULL > - */ > -static char * > -parse_slub_debug_flags(char *str, slab_flags_t *flags, char **slabs, bool init) > -{ > - bool higher_order_disable = false; > - > - /* Skip any completely empty blocks */ > - while (*str && *str == ';') > - str++; > - > - if (*str == ',') { > - /* > - * No options but restriction on slabs. This means full > - * debugging for slabs matching a pattern. > - */ > - *flags = DEBUG_DEFAULT_FLAGS; > - goto check_slabs; > - } > - *flags = 0; > - > - /* Determine which debug features should be switched on */ > - for (; *str && *str != ',' && *str != ';'; str++) { > - switch (tolower(*str)) { > - case '-': > - *flags = 0; > - break; > - case 'f': > - *flags |= SLAB_CONSISTENCY_CHECKS; > - break; > - case 'z': > - *flags |= SLAB_RED_ZONE; > - break; > - case 'p': > - *flags |= SLAB_POISON; > - break; > - case 'u': > - *flags |= SLAB_STORE_USER; > - break; > - case 't': > - *flags |= SLAB_TRACE; > - break; > - case 'a': > - *flags |= SLAB_FAILSLAB; > - break; > - case 'o': > - /* > - * Avoid enabling debugging on caches if its minimum > - * order would increase as a result. > - */ > - higher_order_disable = true; > - break; > - default: > - if (init) > - pr_err("slub_debug option '%c' unknown. skipped\n", *str); > - } > - } > -check_slabs: > - if (*str == ',') > - *slabs = ++str; > - else > - *slabs = NULL; > - > - /* Skip over the slab list */ > - while (*str && *str != ';') > - str++; > - > - /* Skip any completely empty blocks */ > - while (*str && *str == ';') > - str++; > - > - if (init && higher_order_disable) > - disable_higher_order_debug = 1; > - > - if (*str) > - return str; > - else > - return NULL; > -} > - > -static int __init setup_slub_debug(char *str) > -{ > - slab_flags_t flags; > - slab_flags_t global_flags; > - char *saved_str; > - char *slab_list; > - bool global_slub_debug_changed = false; > - bool slab_list_specified = false; > - > - global_flags = DEBUG_DEFAULT_FLAGS; > - if (*str++ != '=' || !*str) > - /* > - * No options specified. Switch on full debugging. > - */ > - goto out; > - > - saved_str = str; > - while (str) { > - str = parse_slub_debug_flags(str, &flags, &slab_list, true); > - > - if (!slab_list) { > - global_flags = flags; > - global_slub_debug_changed = true; > - } else { > - slab_list_specified = true; > - if (flags & SLAB_STORE_USER) > - stack_depot_request_early_init(); > - } > - } > - > - /* > - * For backwards compatibility, a single list of flags with list of > - * slabs means debugging is only changed for those slabs, so the global > - * slub_debug should be unchanged (0 or DEBUG_DEFAULT_FLAGS, depending > - * on CONFIG_SLUB_DEBUG_ON). We can extended that to multiple lists as > - * long as there is no option specifying flags without a slab list. > - */ > - if (slab_list_specified) { > - if (!global_slub_debug_changed) > - global_flags = slub_debug; > - slub_debug_string = saved_str; > - } > -out: > - slub_debug = global_flags; > - if (slub_debug & SLAB_STORE_USER) > - stack_depot_request_early_init(); > - if (slub_debug != 0 || slub_debug_string) > - static_branch_enable(&slub_debug_enabled); > - else > - static_branch_disable(&slub_debug_enabled); > - if ((static_branch_unlikely(&init_on_alloc) || > - static_branch_unlikely(&init_on_free)) && > - (slub_debug & SLAB_POISON)) > - pr_info("mem auto-init: SLAB_POISON will take precedence over init_on_alloc/init_on_free\n"); > - return 1; > -} > - > -__setup("slub_debug", setup_slub_debug); > - > -/* > - * kmem_cache_flags - apply debugging options to the cache > - * @object_size: the size of an object without meta data > - * @flags: flags to set > - * @name: name of the cache > - * > - * Debug option(s) are applied to @flags. In addition to the debug > - * option(s), if a slab name (or multiple) is specified i.e. > - * slub_debug=<Debug-Options>,<slab name1>,<slab name2> ... > - * then only the select slabs will receive the debug option(s). > - */ > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name) > -{ > - char *iter; > - size_t len; > - char *next_block; > - slab_flags_t block_flags; > - slab_flags_t slub_debug_local = slub_debug; > - > - if (flags & SLAB_NO_USER_FLAGS) > - return flags; > - > - /* > - * If the slab cache is for debugging (e.g. kmemleak) then > - * don't store user (stack trace) information by default, > - * but let the user enable it via the command line below. > - */ > - if (flags & SLAB_NOLEAKTRACE) > - slub_debug_local &= ~SLAB_STORE_USER; > - > - len = strlen(name); > - next_block = slub_debug_string; > - /* Go through all blocks of debug options, see if any matches our slab's name */ > - while (next_block) { > - next_block = parse_slub_debug_flags(next_block, &block_flags, &iter, false); > - if (!iter) > - continue; > - /* Found a block that has a slab list, search it */ > - while (*iter) { > - char *end, *glob; > - size_t cmplen; > - > - end = strchrnul(iter, ','); > - if (next_block && next_block < end) > - end = next_block - 1; > - > - glob = strnchr(iter, end - iter, '*'); > - if (glob) > - cmplen = glob - iter; > - else > - cmplen = max_t(size_t, len, (end - iter)); > - > - if (!strncmp(name, iter, cmplen)) { > - flags |= block_flags; > - return flags; > - } > - > - if (!*end || *end == ';') > - break; > - iter = end + 1; > - } > - } > - > - return flags | slub_debug_local; > -} > -#else /* !CONFIG_SLUB_DEBUG */ > -static inline void setup_object_debug(struct kmem_cache *s, void *object) {} > -static inline > -void setup_slab_debug(struct kmem_cache *s, struct slab *slab, void *addr) {} > - > -static inline bool alloc_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *object, int orig_size) { return true; } > - > -static inline bool free_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, int *bulk_cnt, > - unsigned long addr, depot_stack_handle_t handle) { return true; } > - > -static inline void slab_pad_check(struct kmem_cache *s, struct slab *slab) {} > -static inline int check_object(struct kmem_cache *s, struct slab *slab, > - void *object, u8 val) { return 1; } > -static inline depot_stack_handle_t set_track_prepare(void) { return 0; } > -static inline void set_track(struct kmem_cache *s, void *object, > - enum track_item alloc, unsigned long addr) {} > -static inline void add_full(struct kmem_cache *s, struct kmem_cache_node *n, > - struct slab *slab) {} > -static inline void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, > - struct slab *slab) {} > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name) > -{ > - return flags; > -} > -#define slub_debug 0 > - > -#define disable_higher_order_debug 0 > - > -static inline unsigned long slabs_node(struct kmem_cache *s, int node) > - { return 0; } > -static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) > - { return 0; } > -static inline void inc_slabs_node(struct kmem_cache *s, int node, > - int objects) {} > -static inline void dec_slabs_node(struct kmem_cache *s, int node, > - int objects) {} > - > -#ifndef CONFIG_SLUB_TINY > -static bool freelist_corrupted(struct kmem_cache *s, struct slab *slab, > - void **freelist, void *nextfree) > -{ > - return false; > -} > -#endif > -#endif /* CONFIG_SLUB_DEBUG */ > - > -/* > - * Hooks for other subsystems that check memory allocations. In a typical > - * production configuration these hooks all should produce no code at all. > - */ > -static __always_inline bool slab_free_hook(struct kmem_cache *s, > - void *x, bool init) > -{ > - kmemleak_free_recursive(x, s->flags); > - kmsan_slab_free(s, x); > - > - debug_check_no_locks_freed(x, s->object_size); > - > - if (!(s->flags & SLAB_DEBUG_OBJECTS)) > - debug_check_no_obj_freed(x, s->object_size); > - > - /* Use KCSAN to help debug racy use-after-free. */ > - if (!(s->flags & SLAB_TYPESAFE_BY_RCU)) > - __kcsan_check_access(x, s->object_size, > - KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ASSERT); > - > - /* > - * As memory initialization might be integrated into KASAN, > - * kasan_slab_free and initialization memset's must be > - * kept together to avoid discrepancies in behavior. > - * > - * The initialization memset's clear the object and the metadata, > - * but don't touch the SLAB redzone. > - */ > - if (init) { > - int rsize; > - > - if (!kasan_has_integrated_init()) > - memset(kasan_reset_tag(x), 0, s->object_size); > - rsize = (s->flags & SLAB_RED_ZONE) ? s->red_left_pad : 0; > - memset((char *)kasan_reset_tag(x) + s->inuse, 0, > - s->size - s->inuse - rsize); > - } > - /* KASAN might put x into memory quarantine, delaying its reuse. */ > - return kasan_slab_free(s, x, init); > -} > - > -static inline bool slab_free_freelist_hook(struct kmem_cache *s, > - void **head, void **tail, > - int *cnt) > -{ > - > - void *object; > - void *next = *head; > - void *old_tail = *tail ? *tail : *head; > - > - if (is_kfence_address(next)) { > - slab_free_hook(s, next, false); > - return true; > - } > - > - /* Head and tail of the reconstructed freelist */ > - *head = NULL; > - *tail = NULL; > - > - do { > - object = next; > - next = get_freepointer(s, object); > - > - /* If object's reuse doesn't have to be delayed */ > - if (!slab_free_hook(s, object, slab_want_init_on_free(s))) { > - /* Move object to the new freelist */ > - set_freepointer(s, object, *head); > - *head = object; > - if (!*tail) > - *tail = object; > - } else { > - /* > - * Adjust the reconstructed freelist depth > - * accordingly if object's reuse is delayed. > - */ > - --(*cnt); > - } > - } while (object != old_tail); > - > - if (*head == *tail) > - *tail = NULL; > - > - return *head != NULL; > -} > - > -static void *setup_object(struct kmem_cache *s, void *object) > -{ > - setup_object_debug(s, object); > - object = kasan_init_slab_obj(s, object); > - if (unlikely(s->ctor)) { > - kasan_unpoison_object_data(s, object); > - s->ctor(object); > - kasan_poison_object_data(s, object); > - } > - return object; > -} > - > -/* > - * Slab allocation and freeing > - */ > -static inline struct slab *alloc_slab_page(gfp_t flags, int node, > - struct kmem_cache_order_objects oo) > -{ > - struct folio *folio; > - struct slab *slab; > - unsigned int order = oo_order(oo); > - > - if (node == NUMA_NO_NODE) > - folio = (struct folio *)alloc_pages(flags, order); > - else > - folio = (struct folio *)__alloc_pages_node(node, flags, order); > - > - if (!folio) > - return NULL; > - > - slab = folio_slab(folio); > - __folio_set_slab(folio); > - /* Make the flag visible before any changes to folio->mapping */ > - smp_wmb(); > - if (folio_is_pfmemalloc(folio)) > - slab_set_pfmemalloc(slab); > - > - return slab; > -} > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -/* Pre-initialize the random sequence cache */ > -static int init_cache_random_seq(struct kmem_cache *s) > -{ > - unsigned int count = oo_objects(s->oo); > - int err; > - > - /* Bailout if already initialised */ > - if (s->random_seq) > - return 0; > - > - err = cache_random_seq_create(s, count, GFP_KERNEL); > - if (err) { > - pr_err("SLUB: Unable to initialize free list for %s\n", > - s->name); > - return err; > - } > - > - /* Transform to an offset on the set of pages */ > - if (s->random_seq) { > - unsigned int i; > - > - for (i = 0; i < count; i++) > - s->random_seq[i] *= s->size; > - } > - return 0; > -} > - > -/* Initialize each random sequence freelist per cache */ > -static void __init init_freelist_randomization(void) > -{ > - struct kmem_cache *s; > - > - mutex_lock(&slab_mutex); > - > - list_for_each_entry(s, &slab_caches, list) > - init_cache_random_seq(s); > - > - mutex_unlock(&slab_mutex); > -} > - > -/* Get the next entry on the pre-computed freelist randomized */ > -static void *next_freelist_entry(struct kmem_cache *s, struct slab *slab, > - unsigned long *pos, void *start, > - unsigned long page_limit, > - unsigned long freelist_count) > -{ > - unsigned int idx; > - > - /* > - * If the target page allocation failed, the number of objects on the > - * page might be smaller than the usual size defined by the cache. > - */ > - do { > - idx = s->random_seq[*pos]; > - *pos += 1; > - if (*pos >= freelist_count) > - *pos = 0; > - } while (unlikely(idx >= page_limit)); > - > - return (char *)start + idx; > -} > - > -/* Shuffle the single linked freelist based on a random pre-computed sequence */ > -static bool shuffle_freelist(struct kmem_cache *s, struct slab *slab) > -{ > - void *start; > - void *cur; > - void *next; > - unsigned long idx, pos, page_limit, freelist_count; > - > - if (slab->objects < 2 || !s->random_seq) > - return false; > - > - freelist_count = oo_objects(s->oo); > - pos = get_random_u32_below(freelist_count); > - > - page_limit = slab->objects * s->size; > - start = fixup_red_left(s, slab_address(slab)); > - > - /* First entry is used as the base of the freelist */ > - cur = next_freelist_entry(s, slab, &pos, start, page_limit, > - freelist_count); > - cur = setup_object(s, cur); > - slab->freelist = cur; > - > - for (idx = 1; idx < slab->objects; idx++) { > - next = next_freelist_entry(s, slab, &pos, start, page_limit, > - freelist_count); > - next = setup_object(s, next); > - set_freepointer(s, cur, next); > - cur = next; > - } > - set_freepointer(s, cur, NULL); > - > - return true; > -} > -#else > -static inline int init_cache_random_seq(struct kmem_cache *s) > -{ > - return 0; > -} > -static inline void init_freelist_randomization(void) { } > -static inline bool shuffle_freelist(struct kmem_cache *s, struct slab *slab) > -{ > - return false; > -} > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > - > -static struct slab *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) > -{ > - struct slab *slab; > - struct kmem_cache_order_objects oo = s->oo; > - gfp_t alloc_gfp; > - void *start, *p, *next; > - int idx; > - bool shuffle; > - > - flags &= gfp_allowed_mask; > - > - flags |= s->allocflags; > - > - /* > - * Let the initial higher-order allocation fail under memory pressure > - * so we fall-back to the minimum order allocation. > - */ > - alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL; > - if ((alloc_gfp & __GFP_DIRECT_RECLAIM) && oo_order(oo) > oo_order(s->min)) > - alloc_gfp = (alloc_gfp | __GFP_NOMEMALLOC) & ~__GFP_RECLAIM; > - > - slab = alloc_slab_page(alloc_gfp, node, oo); > - if (unlikely(!slab)) { > - oo = s->min; > - alloc_gfp = flags; > - /* > - * Allocation may have failed due to fragmentation. > - * Try a lower order alloc if possible > - */ > - slab = alloc_slab_page(alloc_gfp, node, oo); > - if (unlikely(!slab)) > - return NULL; > - stat(s, ORDER_FALLBACK); > - } > - > - slab->objects = oo_objects(oo); > - slab->inuse = 0; > - slab->frozen = 0; > - > - account_slab(slab, oo_order(oo), s, flags); > - > - slab->slab_cache = s; > - > - kasan_poison_slab(slab); > - > - start = slab_address(slab); > - > - setup_slab_debug(s, slab, start); > - > - shuffle = shuffle_freelist(s, slab); > - > - if (!shuffle) { > - start = fixup_red_left(s, start); > - start = setup_object(s, start); > - slab->freelist = start; > - for (idx = 0, p = start; idx < slab->objects - 1; idx++) { > - next = p + s->size; > - next = setup_object(s, next); > - set_freepointer(s, p, next); > - p = next; > - } > - set_freepointer(s, p, NULL); > - } > - > - return slab; > -} > - > -static struct slab *new_slab(struct kmem_cache *s, gfp_t flags, int node) > -{ > - if (unlikely(flags & GFP_SLAB_BUG_MASK)) > - flags = kmalloc_fix_flags(flags); > - > - WARN_ON_ONCE(s->ctor && (flags & __GFP_ZERO)); > - > - return allocate_slab(s, > - flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node); > -} > - > -static void __free_slab(struct kmem_cache *s, struct slab *slab) > -{ > - struct folio *folio = slab_folio(slab); > - int order = folio_order(folio); > - int pages = 1 << order; > - > - __slab_clear_pfmemalloc(slab); > - folio->mapping = NULL; > - /* Make the mapping reset visible before clearing the flag */ > - smp_wmb(); > - __folio_clear_slab(folio); > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += pages; > - unaccount_slab(slab, order, s); > - __free_pages(&folio->page, order); > -} > - > -static void rcu_free_slab(struct rcu_head *h) > -{ > - struct slab *slab = container_of(h, struct slab, rcu_head); > - > - __free_slab(slab->slab_cache, slab); > -} > - > -static void free_slab(struct kmem_cache *s, struct slab *slab) > -{ > - if (kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) { > - void *p; > - > - slab_pad_check(s, slab); > - for_each_object(p, s, slab_address(slab), slab->objects) > - check_object(s, slab, p, SLUB_RED_INACTIVE); > - } > - > - if (unlikely(s->flags & SLAB_TYPESAFE_BY_RCU)) > - call_rcu(&slab->rcu_head, rcu_free_slab); > - else > - __free_slab(s, slab); > -} > - > -static void discard_slab(struct kmem_cache *s, struct slab *slab) > -{ > - dec_slabs_node(s, slab_nid(slab), slab->objects); > - free_slab(s, slab); > -} > - > -/* > - * Management of partially allocated slabs. > - */ > -static inline void > -__add_partial(struct kmem_cache_node *n, struct slab *slab, int tail) > -{ > - n->nr_partial++; > - if (tail == DEACTIVATE_TO_TAIL) > - list_add_tail(&slab->slab_list, &n->partial); > - else > - list_add(&slab->slab_list, &n->partial); > -} > - > -static inline void add_partial(struct kmem_cache_node *n, > - struct slab *slab, int tail) > -{ > - lockdep_assert_held(&n->list_lock); > - __add_partial(n, slab, tail); > -} > - > -static inline void remove_partial(struct kmem_cache_node *n, > - struct slab *slab) > -{ > - lockdep_assert_held(&n->list_lock); > - list_del(&slab->slab_list); > - n->nr_partial--; > -} > - > -/* > - * Called only for kmem_cache_debug() caches instead of acquire_slab(), with a > - * slab from the n->partial list. Remove only a single object from the slab, do > - * the alloc_debug_processing() checks and leave the slab on the list, or move > - * it to full list if it was the last free object. > - */ > -static void *alloc_single_from_partial(struct kmem_cache *s, > - struct kmem_cache_node *n, struct slab *slab, int orig_size) > -{ > - void *object; > - > - lockdep_assert_held(&n->list_lock); > - > - object = slab->freelist; > - slab->freelist = get_freepointer(s, object); > - slab->inuse++; > - > - if (!alloc_debug_processing(s, slab, object, orig_size)) { > - remove_partial(n, slab); > - return NULL; > - } > - > - if (slab->inuse == slab->objects) { > - remove_partial(n, slab); > - add_full(s, n, slab); > - } > - > - return object; > -} > - > -/* > - * Called only for kmem_cache_debug() caches to allocate from a freshly > - * allocated slab. Allocate a single object instead of whole freelist > - * and put the slab to the partial (or full) list. > - */ > -static void *alloc_single_from_new_slab(struct kmem_cache *s, > - struct slab *slab, int orig_size) > -{ > - int nid = slab_nid(slab); > - struct kmem_cache_node *n = get_node(s, nid); > - unsigned long flags; > - void *object; > - > - > - object = slab->freelist; > - slab->freelist = get_freepointer(s, object); > - slab->inuse = 1; > - > - if (!alloc_debug_processing(s, slab, object, orig_size)) > - /* > - * It's not really expected that this would fail on a > - * freshly allocated slab, but a concurrent memory > - * corruption in theory could cause that. > - */ > - return NULL; > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - if (slab->inuse == slab->objects) > - add_full(s, n, slab); > - else > - add_partial(n, slab, DEACTIVATE_TO_HEAD); > - > - inc_slabs_node(s, nid, slab->objects); > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - return object; > -} > - > -/* > - * Remove slab from the partial list, freeze it and > - * return the pointer to the freelist. > - * > - * Returns a list of objects or NULL if it fails. > - */ > -static inline void *acquire_slab(struct kmem_cache *s, > - struct kmem_cache_node *n, struct slab *slab, > - int mode) > -{ > - void *freelist; > - unsigned long counters; > - struct slab new; > - > - lockdep_assert_held(&n->list_lock); > - > - /* > - * Zap the freelist and set the frozen bit. > - * The old freelist is the list of objects for the > - * per cpu allocation list. > - */ > - freelist = slab->freelist; > - counters = slab->counters; > - new.counters = counters; > - if (mode) { > - new.inuse = slab->objects; > - new.freelist = NULL; > - } else { > - new.freelist = freelist; > - } > - > - VM_BUG_ON(new.frozen); > - new.frozen = 1; > - > - if (!__cmpxchg_double_slab(s, slab, > - freelist, counters, > - new.freelist, new.counters, > - "acquire_slab")) > - return NULL; > - > - remove_partial(n, slab); > - WARN_ON(!freelist); > - return freelist; > -} > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -static void put_cpu_partial(struct kmem_cache *s, struct slab *slab, int drain); > -#else > -static inline void put_cpu_partial(struct kmem_cache *s, struct slab *slab, > - int drain) { } > -#endif > -static inline bool pfmemalloc_match(struct slab *slab, gfp_t gfpflags); > - > -/* > - * Try to allocate a partial slab from a specific node. > - */ > -static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n, > - struct partial_context *pc) > -{ > - struct slab *slab, *slab2; > - void *object = NULL; > - unsigned long flags; > - unsigned int partial_slabs = 0; > - > - /* > - * Racy check. If we mistakenly see no partial slabs then we > - * just allocate an empty slab. If we mistakenly try to get a > - * partial slab and there is none available then get_partial() > - * will return NULL. > - */ > - if (!n || !n->nr_partial) > - return NULL; > - > - spin_lock_irqsave(&n->list_lock, flags); > - list_for_each_entry_safe(slab, slab2, &n->partial, slab_list) { > - void *t; > - > - if (!pfmemalloc_match(slab, pc->flags)) > - continue; > - > - if (IS_ENABLED(CONFIG_SLUB_TINY) || kmem_cache_debug(s)) { > - object = alloc_single_from_partial(s, n, slab, > - pc->orig_size); > - if (object) > - break; > - continue; > - } > - > - t = acquire_slab(s, n, slab, object == NULL); > - if (!t) > - break; > - > - if (!object) { > - *pc->slab = slab; > - stat(s, ALLOC_FROM_PARTIAL); > - object = t; > - } else { > - put_cpu_partial(s, slab, 0); > - stat(s, CPU_PARTIAL_NODE); > - partial_slabs++; > - } > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - if (!kmem_cache_has_cpu_partial(s) > - || partial_slabs > s->cpu_partial_slabs / 2) > - break; > -#else > - break; > -#endif > - > - } > - spin_unlock_irqrestore(&n->list_lock, flags); > - return object; > -} > - > -/* > - * Get a slab from somewhere. Search in increasing NUMA distances. > - */ > -static void *get_any_partial(struct kmem_cache *s, struct partial_context *pc) > -{ > -#ifdef CONFIG_NUMA > - struct zonelist *zonelist; > - struct zoneref *z; > - struct zone *zone; > - enum zone_type highest_zoneidx = gfp_zone(pc->flags); > - void *object; > - unsigned int cpuset_mems_cookie; > - > - /* > - * The defrag ratio allows a configuration of the tradeoffs between > - * inter node defragmentation and node local allocations. A lower > - * defrag_ratio increases the tendency to do local allocations > - * instead of attempting to obtain partial slabs from other nodes. > - * > - * If the defrag_ratio is set to 0 then kmalloc() always > - * returns node local objects. If the ratio is higher then kmalloc() > - * may return off node objects because partial slabs are obtained > - * from other nodes and filled up. > - * > - * If /sys/kernel/slab/xx/remote_node_defrag_ratio is set to 100 > - * (which makes defrag_ratio = 1000) then every (well almost) > - * allocation will first attempt to defrag slab caches on other nodes. > - * This means scanning over all nodes to look for partial slabs which > - * may be expensive if we do it every time we are trying to find a slab > - * with available objects. > - */ > - if (!s->remote_node_defrag_ratio || > - get_cycles() % 1024 > s->remote_node_defrag_ratio) > - return NULL; > - > - do { > - cpuset_mems_cookie = read_mems_allowed_begin(); > - zonelist = node_zonelist(mempolicy_slab_node(), pc->flags); > - for_each_zone_zonelist(zone, z, zonelist, highest_zoneidx) { > - struct kmem_cache_node *n; > - > - n = get_node(s, zone_to_nid(zone)); > - > - if (n && cpuset_zone_allowed(zone, pc->flags) && > - n->nr_partial > s->min_partial) { > - object = get_partial_node(s, n, pc); > - if (object) { > - /* > - * Don't check read_mems_allowed_retry() > - * here - if mems_allowed was updated in > - * parallel, that was a harmless race > - * between allocation and the cpuset > - * update > - */ > - return object; > - } > - } > - } > - } while (read_mems_allowed_retry(cpuset_mems_cookie)); > -#endif /* CONFIG_NUMA */ > - return NULL; > -} > - > -/* > - * Get a partial slab, lock it and return it. > - */ > -static void *get_partial(struct kmem_cache *s, int node, struct partial_context *pc) > -{ > - void *object; > - int searchnode = node; > - > - if (node == NUMA_NO_NODE) > - searchnode = numa_mem_id(); > - > - object = get_partial_node(s, get_node(s, searchnode), pc); > - if (object || node != NUMA_NO_NODE) > - return object; > - > - return get_any_partial(s, pc); > -} > - > -#ifndef CONFIG_SLUB_TINY > - > -#ifdef CONFIG_PREEMPTION > -/* > - * Calculate the next globally unique transaction for disambiguation > - * during cmpxchg. The transactions start with the cpu number and are then > - * incremented by CONFIG_NR_CPUS. > - */ > -#define TID_STEP roundup_pow_of_two(CONFIG_NR_CPUS) > -#else > -/* > - * No preemption supported therefore also no need to check for > - * different cpus. > - */ > -#define TID_STEP 1 > -#endif /* CONFIG_PREEMPTION */ > - > -static inline unsigned long next_tid(unsigned long tid) > -{ > - return tid + TID_STEP; > -} > - > -#ifdef SLUB_DEBUG_CMPXCHG > -static inline unsigned int tid_to_cpu(unsigned long tid) > -{ > - return tid % TID_STEP; > -} > - > -static inline unsigned long tid_to_event(unsigned long tid) > -{ > - return tid / TID_STEP; > -} > -#endif > - > -static inline unsigned int init_tid(int cpu) > -{ > - return cpu; > -} > - > -static inline void note_cmpxchg_failure(const char *n, > - const struct kmem_cache *s, unsigned long tid) > -{ > -#ifdef SLUB_DEBUG_CMPXCHG > - unsigned long actual_tid = __this_cpu_read(s->cpu_slab->tid); > - > - pr_info("%s %s: cmpxchg redo ", n, s->name); > - > -#ifdef CONFIG_PREEMPTION > - if (tid_to_cpu(tid) != tid_to_cpu(actual_tid)) > - pr_warn("due to cpu change %d -> %d\n", > - tid_to_cpu(tid), tid_to_cpu(actual_tid)); > - else > -#endif > - if (tid_to_event(tid) != tid_to_event(actual_tid)) > - pr_warn("due to cpu running other code. Event %ld->%ld\n", > - tid_to_event(tid), tid_to_event(actual_tid)); > - else > - pr_warn("for unknown reason: actual=%lx was=%lx target=%lx\n", > - actual_tid, tid, next_tid(tid)); > -#endif > - stat(s, CMPXCHG_DOUBLE_CPU_FAIL); > -} > - > -static void init_kmem_cache_cpus(struct kmem_cache *s) > -{ > - int cpu; > - struct kmem_cache_cpu *c; > - > - for_each_possible_cpu(cpu) { > - c = per_cpu_ptr(s->cpu_slab, cpu); > - local_lock_init(&c->lock); > - c->tid = init_tid(cpu); > - } > -} > - > -/* > - * Finishes removing the cpu slab. Merges cpu's freelist with slab's freelist, > - * unfreezes the slabs and puts it on the proper list. > - * Assumes the slab has been already safely taken away from kmem_cache_cpu > - * by the caller. > - */ > -static void deactivate_slab(struct kmem_cache *s, struct slab *slab, > - void *freelist) > -{ > - enum slab_modes { M_NONE, M_PARTIAL, M_FREE, M_FULL_NOLIST }; > - struct kmem_cache_node *n = get_node(s, slab_nid(slab)); > - int free_delta = 0; > - enum slab_modes mode = M_NONE; > - void *nextfree, *freelist_iter, *freelist_tail; > - int tail = DEACTIVATE_TO_HEAD; > - unsigned long flags = 0; > - struct slab new; > - struct slab old; > - > - if (slab->freelist) { > - stat(s, DEACTIVATE_REMOTE_FREES); > - tail = DEACTIVATE_TO_TAIL; > - } > - > - /* > - * Stage one: Count the objects on cpu's freelist as free_delta and > - * remember the last object in freelist_tail for later splicing. > - */ > - freelist_tail = NULL; > - freelist_iter = freelist; > - while (freelist_iter) { > - nextfree = get_freepointer(s, freelist_iter); > - > - /* > - * If 'nextfree' is invalid, it is possible that the object at > - * 'freelist_iter' is already corrupted. So isolate all objects > - * starting at 'freelist_iter' by skipping them. > - */ > - if (freelist_corrupted(s, slab, &freelist_iter, nextfree)) > - break; > - > - freelist_tail = freelist_iter; > - free_delta++; > - > - freelist_iter = nextfree; > - } > - > - /* > - * Stage two: Unfreeze the slab while splicing the per-cpu > - * freelist to the head of slab's freelist. > - * > - * Ensure that the slab is unfrozen while the list presence > - * reflects the actual number of objects during unfreeze. > - * > - * We first perform cmpxchg holding lock and insert to list > - * when it succeed. If there is mismatch then the slab is not > - * unfrozen and number of objects in the slab may have changed. > - * Then release lock and retry cmpxchg again. > - */ > -redo: > - > - old.freelist = READ_ONCE(slab->freelist); > - old.counters = READ_ONCE(slab->counters); > - VM_BUG_ON(!old.frozen); > - > - /* Determine target state of the slab */ > - new.counters = old.counters; > - if (freelist_tail) { > - new.inuse -= free_delta; > - set_freepointer(s, freelist_tail, old.freelist); > - new.freelist = freelist; > - } else > - new.freelist = old.freelist; > - > - new.frozen = 0; > - > - if (!new.inuse && n->nr_partial >= s->min_partial) { > - mode = M_FREE; > - } else if (new.freelist) { > - mode = M_PARTIAL; > - /* > - * Taking the spinlock removes the possibility that > - * acquire_slab() will see a slab that is frozen > - */ > - spin_lock_irqsave(&n->list_lock, flags); > - } else { > - mode = M_FULL_NOLIST; > - } > - > - > - if (!cmpxchg_double_slab(s, slab, > - old.freelist, old.counters, > - new.freelist, new.counters, > - "unfreezing slab")) { > - if (mode == M_PARTIAL) > - spin_unlock_irqrestore(&n->list_lock, flags); > - goto redo; > - } > - > - > - if (mode == M_PARTIAL) { > - add_partial(n, slab, tail); > - spin_unlock_irqrestore(&n->list_lock, flags); > - stat(s, tail); > - } else if (mode == M_FREE) { > - stat(s, DEACTIVATE_EMPTY); > - discard_slab(s, slab); > - stat(s, FREE_SLAB); > - } else if (mode == M_FULL_NOLIST) { > - stat(s, DEACTIVATE_FULL); > - } > -} > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -static void __unfreeze_partials(struct kmem_cache *s, struct slab *partial_slab) > -{ > - struct kmem_cache_node *n = NULL, *n2 = NULL; > - struct slab *slab, *slab_to_discard = NULL; > - unsigned long flags = 0; > - > - while (partial_slab) { > - struct slab new; > - struct slab old; > - > - slab = partial_slab; > - partial_slab = slab->next; > - > - n2 = get_node(s, slab_nid(slab)); > - if (n != n2) { > - if (n) > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - n = n2; > - spin_lock_irqsave(&n->list_lock, flags); > - } > - > - do { > - > - old.freelist = slab->freelist; > - old.counters = slab->counters; > - VM_BUG_ON(!old.frozen); > - > - new.counters = old.counters; > - new.freelist = old.freelist; > - > - new.frozen = 0; > - > - } while (!__cmpxchg_double_slab(s, slab, > - old.freelist, old.counters, > - new.freelist, new.counters, > - "unfreezing slab")); > - > - if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) { > - slab->next = slab_to_discard; > - slab_to_discard = slab; > - } else { > - add_partial(n, slab, DEACTIVATE_TO_TAIL); > - stat(s, FREE_ADD_PARTIAL); > - } > - } > - > - if (n) > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - while (slab_to_discard) { > - slab = slab_to_discard; > - slab_to_discard = slab_to_discard->next; > - > - stat(s, DEACTIVATE_EMPTY); > - discard_slab(s, slab); > - stat(s, FREE_SLAB); > - } > -} > - > -/* > - * Unfreeze all the cpu partial slabs. > - */ > -static void unfreeze_partials(struct kmem_cache *s) > -{ > - struct slab *partial_slab; > - unsigned long flags; > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - partial_slab = this_cpu_read(s->cpu_slab->partial); > - this_cpu_write(s->cpu_slab->partial, NULL); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - if (partial_slab) > - __unfreeze_partials(s, partial_slab); > -} > - > -static void unfreeze_partials_cpu(struct kmem_cache *s, > - struct kmem_cache_cpu *c) > -{ > - struct slab *partial_slab; > - > - partial_slab = slub_percpu_partial(c); > - c->partial = NULL; > - > - if (partial_slab) > - __unfreeze_partials(s, partial_slab); > -} > - > -/* > - * Put a slab that was just frozen (in __slab_free|get_partial_node) into a > - * partial slab slot if available. > - * > - * If we did not find a slot then simply move all the partials to the > - * per node partial list. > - */ > -static void put_cpu_partial(struct kmem_cache *s, struct slab *slab, int drain) > -{ > - struct slab *oldslab; > - struct slab *slab_to_unfreeze = NULL; > - unsigned long flags; > - int slabs = 0; > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - > - oldslab = this_cpu_read(s->cpu_slab->partial); > - > - if (oldslab) { > - if (drain && oldslab->slabs >= s->cpu_partial_slabs) { > - /* > - * Partial array is full. Move the existing set to the > - * per node partial list. Postpone the actual unfreezing > - * outside of the critical section. > - */ > - slab_to_unfreeze = oldslab; > - oldslab = NULL; > - } else { > - slabs = oldslab->slabs; > - } > - } > - > - slabs++; > - > - slab->slabs = slabs; > - slab->next = oldslab; > - > - this_cpu_write(s->cpu_slab->partial, slab); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - if (slab_to_unfreeze) { > - __unfreeze_partials(s, slab_to_unfreeze); > - stat(s, CPU_PARTIAL_DRAIN); > - } > -} > - > -#else /* CONFIG_SLUB_CPU_PARTIAL */ > - > -static inline void unfreeze_partials(struct kmem_cache *s) { } > -static inline void unfreeze_partials_cpu(struct kmem_cache *s, > - struct kmem_cache_cpu *c) { } > - > -#endif /* CONFIG_SLUB_CPU_PARTIAL */ > - > -static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) > -{ > - unsigned long flags; > - struct slab *slab; > - void *freelist; > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - > - slab = c->slab; > - freelist = c->freelist; > - > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - if (slab) { > - deactivate_slab(s, slab, freelist); > - stat(s, CPUSLAB_FLUSH); > - } > -} > - > -static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) > -{ > - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); > - void *freelist = c->freelist; > - struct slab *slab = c->slab; > - > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - > - if (slab) { > - deactivate_slab(s, slab, freelist); > - stat(s, CPUSLAB_FLUSH); > - } > - > - unfreeze_partials_cpu(s, c); > -} > - > -struct slub_flush_work { > - struct work_struct work; > - struct kmem_cache *s; > - bool skip; > -}; > - > -/* > - * Flush cpu slab. > - * > - * Called from CPU work handler with migration disabled. > - */ > -static void flush_cpu_slab(struct work_struct *w) > -{ > - struct kmem_cache *s; > - struct kmem_cache_cpu *c; > - struct slub_flush_work *sfw; > - > - sfw = container_of(w, struct slub_flush_work, work); > - > - s = sfw->s; > - c = this_cpu_ptr(s->cpu_slab); > - > - if (c->slab) > - flush_slab(s, c); > - > - unfreeze_partials(s); > -} > - > -static bool has_cpu_slab(int cpu, struct kmem_cache *s) > -{ > - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); > - > - return c->slab || slub_percpu_partial(c); > -} > - > -static DEFINE_MUTEX(flush_lock); > -static DEFINE_PER_CPU(struct slub_flush_work, slub_flush); > - > -static void flush_all_cpus_locked(struct kmem_cache *s) > -{ > - struct slub_flush_work *sfw; > - unsigned int cpu; > - > - lockdep_assert_cpus_held(); > - mutex_lock(&flush_lock); > - > - for_each_online_cpu(cpu) { > - sfw = &per_cpu(slub_flush, cpu); > - if (!has_cpu_slab(cpu, s)) { > - sfw->skip = true; > - continue; > - } > - INIT_WORK(&sfw->work, flush_cpu_slab); > - sfw->skip = false; > - sfw->s = s; > - queue_work_on(cpu, flushwq, &sfw->work); > - } > - > - for_each_online_cpu(cpu) { > - sfw = &per_cpu(slub_flush, cpu); > - if (sfw->skip) > - continue; > - flush_work(&sfw->work); > - } > - > - mutex_unlock(&flush_lock); > -} > - > -static void flush_all(struct kmem_cache *s) > -{ > - cpus_read_lock(); > - flush_all_cpus_locked(s); > - cpus_read_unlock(); > -} > - > -/* > - * Use the cpu notifier to insure that the cpu slabs are flushed when > - * necessary. > - */ > -static int slub_cpu_dead(unsigned int cpu) > -{ > - struct kmem_cache *s; > - > - mutex_lock(&slab_mutex); > - list_for_each_entry(s, &slab_caches, list) > - __flush_cpu_slab(s, cpu); > - mutex_unlock(&slab_mutex); > - return 0; > -} > - > -#else /* CONFIG_SLUB_TINY */ > -static inline void flush_all_cpus_locked(struct kmem_cache *s) { } > -static inline void flush_all(struct kmem_cache *s) { } > -static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) { } > -static inline int slub_cpu_dead(unsigned int cpu) { return 0; } > -#endif /* CONFIG_SLUB_TINY */ > - > -/* > - * Check if the objects in a per cpu structure fit numa > - * locality expectations. > - */ > -static inline int node_match(struct slab *slab, int node) > -{ > -#ifdef CONFIG_NUMA > - if (node != NUMA_NO_NODE && slab_nid(slab) != node) > - return 0; > -#endif > - return 1; > -} > - > -#ifdef CONFIG_SLUB_DEBUG > -static int count_free(struct slab *slab) > -{ > - return slab->objects - slab->inuse; > -} > - > -static inline unsigned long node_nr_objs(struct kmem_cache_node *n) > -{ > - return atomic_long_read(&n->total_objects); > -} > - > -/* Supports checking bulk free of a constructed freelist */ > -static inline bool free_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, int *bulk_cnt, > - unsigned long addr, depot_stack_handle_t handle) > -{ > - bool checks_ok = false; > - void *object = head; > - int cnt = 0; > - > - if (s->flags & SLAB_CONSISTENCY_CHECKS) { > - if (!check_slab(s, slab)) > - goto out; > - } > - > - if (slab->inuse < *bulk_cnt) { > - slab_err(s, slab, "Slab has %d allocated objects but %d are to be freed\n", > - slab->inuse, *bulk_cnt); > - goto out; > - } > - > -next_object: > - > - if (++cnt > *bulk_cnt) > - goto out_cnt; > - > - if (s->flags & SLAB_CONSISTENCY_CHECKS) { > - if (!free_consistency_checks(s, slab, object, addr)) > - goto out; > - } > - > - if (s->flags & SLAB_STORE_USER) > - set_track_update(s, object, TRACK_FREE, addr, handle); > - trace(s, slab, object, 0); > - /* Freepointer not overwritten by init_object(), SLAB_POISON moved it */ > - init_object(s, object, SLUB_RED_INACTIVE); > - > - /* Reached end of constructed freelist yet? */ > - if (object != tail) { > - object = get_freepointer(s, object); > - goto next_object; > - } > - checks_ok = true; > - > -out_cnt: > - if (cnt != *bulk_cnt) { > - slab_err(s, slab, "Bulk free expected %d objects but found %d\n", > - *bulk_cnt, cnt); > - *bulk_cnt = cnt; > - } > - > -out: > - > - if (!checks_ok) > - slab_fix(s, "Object at 0x%p not freed", object); > - > - return checks_ok; > -} > -#endif /* CONFIG_SLUB_DEBUG */ > - > -#if defined(CONFIG_SLUB_DEBUG) || defined(SLAB_SUPPORTS_SYSFS) > -static unsigned long count_partial(struct kmem_cache_node *n, > - int (*get_count)(struct slab *)) > -{ > - unsigned long flags; > - unsigned long x = 0; > - struct slab *slab; > - > - spin_lock_irqsave(&n->list_lock, flags); > - list_for_each_entry(slab, &n->partial, slab_list) > - x += get_count(slab); > - spin_unlock_irqrestore(&n->list_lock, flags); > - return x; > -} > -#endif /* CONFIG_SLUB_DEBUG || SLAB_SUPPORTS_SYSFS */ > - > -#ifdef CONFIG_SLUB_DEBUG > -static noinline void > -slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) > -{ > - static DEFINE_RATELIMIT_STATE(slub_oom_rs, DEFAULT_RATELIMIT_INTERVAL, > - DEFAULT_RATELIMIT_BURST); > - int node; > - struct kmem_cache_node *n; > - > - if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slub_oom_rs)) > - return; > - > - pr_warn("SLUB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", > - nid, gfpflags, &gfpflags); > - pr_warn(" cache: %s, object size: %u, buffer size: %u, default order: %u, min order: %u\n", > - s->name, s->object_size, s->size, oo_order(s->oo), > - oo_order(s->min)); > - > - if (oo_order(s->min) > get_order(s->object_size)) > - pr_warn(" %s debugging increased min order, use slub_debug=O to disable.\n", > - s->name); > - > - for_each_kmem_cache_node(s, node, n) { > - unsigned long nr_slabs; > - unsigned long nr_objs; > - unsigned long nr_free; > - > - nr_free = count_partial(n, count_free); > - nr_slabs = node_nr_slabs(n); > - nr_objs = node_nr_objs(n); > - > - pr_warn(" node %d: slabs: %ld, objs: %ld, free: %ld\n", > - node, nr_slabs, nr_objs, nr_free); > - } > -} > -#else /* CONFIG_SLUB_DEBUG */ > -static inline void > -slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) { } > -#endif > - > -static inline bool pfmemalloc_match(struct slab *slab, gfp_t gfpflags) > -{ > - if (unlikely(slab_test_pfmemalloc(slab))) > - return gfp_pfmemalloc_allowed(gfpflags); > - > - return true; > -} > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Check the slab->freelist and either transfer the freelist to the > - * per cpu freelist or deactivate the slab. > - * > - * The slab is still frozen if the return value is not NULL. > - * > - * If this function returns NULL then the slab has been unfrozen. > - */ > -static inline void *get_freelist(struct kmem_cache *s, struct slab *slab) > -{ > - struct slab new; > - unsigned long counters; > - void *freelist; > - > - lockdep_assert_held(this_cpu_ptr(&s->cpu_slab->lock)); > - > - do { > - freelist = slab->freelist; > - counters = slab->counters; > - > - new.counters = counters; > - VM_BUG_ON(!new.frozen); > - > - new.inuse = slab->objects; > - new.frozen = freelist != NULL; > - > - } while (!__cmpxchg_double_slab(s, slab, > - freelist, counters, > - NULL, new.counters, > - "get_freelist")); > - > - return freelist; > -} > - > -/* > - * Slow path. The lockless freelist is empty or we need to perform > - * debugging duties. > - * > - * Processing is still very fast if new objects have been freed to the > - * regular freelist. In that case we simply take over the regular freelist > - * as the lockless freelist and zap the regular freelist. > - * > - * If that is not working then we fall back to the partial lists. We take the > - * first element of the freelist as the object to allocate now and move the > - * rest of the freelist to the lockless freelist. > - * > - * And if we were unable to get a new slab from the partial slab lists then > - * we need to allocate a new slab. This is the slowest path since it involves > - * a call to the page allocator and the setup of a new slab. > - * > - * Version of __slab_alloc to use when we know that preemption is > - * already disabled (which is the case for bulk allocation). > - */ > -static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, > - unsigned long addr, struct kmem_cache_cpu *c, unsigned int orig_size) > -{ > - void *freelist; > - struct slab *slab; > - unsigned long flags; > - struct partial_context pc; > - > - stat(s, ALLOC_SLOWPATH); > - > -reread_slab: > - > - slab = READ_ONCE(c->slab); > - if (!slab) { > - /* > - * if the node is not online or has no normal memory, just > - * ignore the node constraint > - */ > - if (unlikely(node != NUMA_NO_NODE && > - !node_isset(node, slab_nodes))) > - node = NUMA_NO_NODE; > - goto new_slab; > - } > -redo: > - > - if (unlikely(!node_match(slab, node))) { > - /* > - * same as above but node_match() being false already > - * implies node != NUMA_NO_NODE > - */ > - if (!node_isset(node, slab_nodes)) { > - node = NUMA_NO_NODE; > - } else { > - stat(s, ALLOC_NODE_MISMATCH); > - goto deactivate_slab; > - } > - } > - > - /* > - * By rights, we should be searching for a slab page that was > - * PFMEMALLOC but right now, we are losing the pfmemalloc > - * information when the page leaves the per-cpu allocator > - */ > - if (unlikely(!pfmemalloc_match(slab, gfpflags))) > - goto deactivate_slab; > - > - /* must check again c->slab in case we got preempted and it changed */ > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (unlikely(slab != c->slab)) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - goto reread_slab; > - } > - freelist = c->freelist; > - if (freelist) > - goto load_freelist; > - > - freelist = get_freelist(s, slab); > - > - if (!freelist) { > - c->slab = NULL; > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - stat(s, DEACTIVATE_BYPASS); > - goto new_slab; > - } > - > - stat(s, ALLOC_REFILL); > - > -load_freelist: > - > - lockdep_assert_held(this_cpu_ptr(&s->cpu_slab->lock)); > - > - /* > - * freelist is pointing to the list of objects to be used. > - * slab is pointing to the slab from which the objects are obtained. > - * That slab must be frozen for per cpu allocations to work. > - */ > - VM_BUG_ON(!c->slab->frozen); > - c->freelist = get_freepointer(s, freelist); > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - return freelist; > - > -deactivate_slab: > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (slab != c->slab) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - goto reread_slab; > - } > - freelist = c->freelist; > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - deactivate_slab(s, slab, freelist); > - > -new_slab: > - > - if (slub_percpu_partial(c)) { > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (unlikely(c->slab)) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - goto reread_slab; > - } > - if (unlikely(!slub_percpu_partial(c))) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - /* we were preempted and partial list got empty */ > - goto new_objects; > - } > - > - slab = c->slab = slub_percpu_partial(c); > - slub_set_percpu_partial(c, slab); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - stat(s, CPU_PARTIAL_ALLOC); > - goto redo; > - } > - > -new_objects: > - > - pc.flags = gfpflags; > - pc.slab = &slab; > - pc.orig_size = orig_size; > - freelist = get_partial(s, node, &pc); > - if (freelist) > - goto check_new_slab; > - > - slub_put_cpu_ptr(s->cpu_slab); > - slab = new_slab(s, gfpflags, node); > - c = slub_get_cpu_ptr(s->cpu_slab); > - > - if (unlikely(!slab)) { > - slab_out_of_memory(s, gfpflags, node); > - return NULL; > - } > - > - stat(s, ALLOC_SLAB); > - > - if (kmem_cache_debug(s)) { > - freelist = alloc_single_from_new_slab(s, slab, orig_size); > - > - if (unlikely(!freelist)) > - goto new_objects; > - > - if (s->flags & SLAB_STORE_USER) > - set_track(s, freelist, TRACK_ALLOC, addr); > - > - return freelist; > - } > - > - /* > - * No other reference to the slab yet so we can > - * muck around with it freely without cmpxchg > - */ > - freelist = slab->freelist; > - slab->freelist = NULL; > - slab->inuse = slab->objects; > - slab->frozen = 1; > - > - inc_slabs_node(s, slab_nid(slab), slab->objects); > - > -check_new_slab: > - > - if (kmem_cache_debug(s)) { > - /* > - * For debug caches here we had to go through > - * alloc_single_from_partial() so just store the tracking info > - * and return the object > - */ > - if (s->flags & SLAB_STORE_USER) > - set_track(s, freelist, TRACK_ALLOC, addr); > - > - return freelist; > - } > - > - if (unlikely(!pfmemalloc_match(slab, gfpflags))) { > - /* > - * For !pfmemalloc_match() case we don't load freelist so that > - * we don't make further mismatched allocations easier. > - */ > - deactivate_slab(s, slab, get_freepointer(s, freelist)); > - return freelist; > - } > - > -retry_load_slab: > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (unlikely(c->slab)) { > - void *flush_freelist = c->freelist; > - struct slab *flush_slab = c->slab; > - > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - deactivate_slab(s, flush_slab, flush_freelist); > - > - stat(s, CPUSLAB_FLUSH); > - > - goto retry_load_slab; > - } > - c->slab = slab; > - > - goto load_freelist; > -} > - > -/* > - * A wrapper for ___slab_alloc() for contexts where preemption is not yet > - * disabled. Compensates for possible cpu changes by refetching the per cpu area > - * pointer. > - */ > -static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, > - unsigned long addr, struct kmem_cache_cpu *c, unsigned int orig_size) > -{ > - void *p; > - > -#ifdef CONFIG_PREEMPT_COUNT > - /* > - * We may have been preempted and rescheduled on a different > - * cpu before disabling preemption. Need to reload cpu area > - * pointer. > - */ > - c = slub_get_cpu_ptr(s->cpu_slab); > -#endif > - > - p = ___slab_alloc(s, gfpflags, node, addr, c, orig_size); > -#ifdef CONFIG_PREEMPT_COUNT > - slub_put_cpu_ptr(s->cpu_slab); > -#endif > - return p; > -} > - > -static __always_inline void *__slab_alloc_node(struct kmem_cache *s, > - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) > -{ > - struct kmem_cache_cpu *c; > - struct slab *slab; > - unsigned long tid; > - void *object; > - > -redo: > - /* > - * Must read kmem_cache cpu data via this cpu ptr. Preemption is > - * enabled. We may switch back and forth between cpus while > - * reading from one cpu area. That does not matter as long > - * as we end up on the original cpu again when doing the cmpxchg. > - * > - * We must guarantee that tid and kmem_cache_cpu are retrieved on the > - * same cpu. We read first the kmem_cache_cpu pointer and use it to read > - * the tid. If we are preempted and switched to another cpu between the > - * two reads, it's OK as the two are still associated with the same cpu > - * and cmpxchg later will validate the cpu. > - */ > - c = raw_cpu_ptr(s->cpu_slab); > - tid = READ_ONCE(c->tid); > - > - /* > - * Irqless object alloc/free algorithm used here depends on sequence > - * of fetching cpu_slab's data. tid should be fetched before anything > - * on c to guarantee that object and slab associated with previous tid > - * won't be used with current tid. If we fetch tid first, object and > - * slab could be one associated with next tid and our alloc/free > - * request will be failed. In this case, we will retry. So, no problem. > - */ > - barrier(); > - > - /* > - * The transaction ids are globally unique per cpu and per operation on > - * a per cpu queue. Thus they can be guarantee that the cmpxchg_double > - * occurs on the right processor and that there was no operation on the > - * linked list in between. > - */ > - > - object = c->freelist; > - slab = c->slab; > - > - if (!USE_LOCKLESS_FAST_PATH() || > - unlikely(!object || !slab || !node_match(slab, node))) { > - object = __slab_alloc(s, gfpflags, node, addr, c, orig_size); > - } else { > - void *next_object = get_freepointer_safe(s, object); > - > - /* > - * The cmpxchg will only match if there was no additional > - * operation and if we are on the right processor. > - * > - * The cmpxchg does the following atomically (without lock > - * semantics!) > - * 1. Relocate first pointer to the current per cpu area. > - * 2. Verify that tid and freelist have not been changed > - * 3. If they were not changed replace tid and freelist > - * > - * Since this is without lock semantics the protection is only > - * against code executing on this cpu *not* from access by > - * other cpus. > - */ > - if (unlikely(!this_cpu_cmpxchg_double( > - s->cpu_slab->freelist, s->cpu_slab->tid, > - object, tid, > - next_object, next_tid(tid)))) { > - > - note_cmpxchg_failure("slab_alloc", s, tid); > - goto redo; > - } > - prefetch_freepointer(s, next_object); > - stat(s, ALLOC_FASTPATH); > - } > - > - return object; > -} > -#else /* CONFIG_SLUB_TINY */ > -static void *__slab_alloc_node(struct kmem_cache *s, > - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) > -{ > - struct partial_context pc; > - struct slab *slab; > - void *object; > - > - pc.flags = gfpflags; > - pc.slab = &slab; > - pc.orig_size = orig_size; > - object = get_partial(s, node, &pc); > - > - if (object) > - return object; > - > - slab = new_slab(s, gfpflags, node); > - if (unlikely(!slab)) { > - slab_out_of_memory(s, gfpflags, node); > - return NULL; > - } > - > - object = alloc_single_from_new_slab(s, slab, orig_size); > - > - return object; > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -/* > - * If the object has been wiped upon free, make sure it's fully initialized by > - * zeroing out freelist pointer. > - */ > -static __always_inline void maybe_wipe_obj_freeptr(struct kmem_cache *s, > - void *obj) > -{ > - if (unlikely(slab_want_init_on_free(s)) && obj) > - memset((void *)((char *)kasan_reset_tag(obj) + s->offset), > - 0, sizeof(void *)); > -} > - > -/* > - * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc) > - * have the fastpath folded into their functions. So no function call > - * overhead for requests that can be satisfied on the fastpath. > - * > - * The fastpath works by first checking if the lockless freelist can be used. > - * If not then __slab_alloc is called for slow processing. > - * > - * Otherwise we can simply pick the next object from the lockless free list. > - */ > -static __fastpath_inline void *slab_alloc_node(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) > -{ > - void *object; > - struct obj_cgroup *objcg = NULL; > - bool init = false; > - > - s = slab_pre_alloc_hook(s, lru, &objcg, 1, gfpflags); > - if (!s) > - return NULL; > - > - object = kfence_alloc(s, orig_size, gfpflags); > - if (unlikely(object)) > - goto out; > - > - object = __slab_alloc_node(s, gfpflags, node, addr, orig_size); > - > - maybe_wipe_obj_freeptr(s, object); > - init = slab_want_init_on_alloc(gfpflags, s); > - > -out: > - /* > - * When init equals 'true', like for kzalloc() family, only > - * @orig_size bytes might be zeroed instead of s->object_size > - */ > - slab_post_alloc_hook(s, objcg, gfpflags, 1, &object, init, orig_size); > - > - return object; > -} > - > -static __fastpath_inline void *slab_alloc(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags, unsigned long addr, size_t orig_size) > -{ > - return slab_alloc_node(s, lru, gfpflags, NUMA_NO_NODE, addr, orig_size); > -} > - > -static __fastpath_inline > -void *__kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags) > -{ > - void *ret = slab_alloc(s, lru, gfpflags, _RET_IP_, s->object_size); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, s, gfpflags, NUMA_NO_NODE); > - > - return ret; > -} > - > -void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) > -{ > - return __kmem_cache_alloc_lru(s, NULL, gfpflags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc); > - > -void *kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags) > -{ > - return __kmem_cache_alloc_lru(s, lru, gfpflags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_lru); > - > -void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, > - int node, size_t orig_size, > - unsigned long caller) > -{ > - return slab_alloc_node(s, NULL, gfpflags, node, > - caller, orig_size); > -} > - > -void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node) > -{ > - void *ret = slab_alloc_node(s, NULL, gfpflags, node, _RET_IP_, s->object_size); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, s, gfpflags, node); > - > - return ret; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_node); > - > -static noinline void free_to_partial_list( > - struct kmem_cache *s, struct slab *slab, > - void *head, void *tail, int bulk_cnt, > - unsigned long addr) > -{ > - struct kmem_cache_node *n = get_node(s, slab_nid(slab)); > - struct slab *slab_free = NULL; > - int cnt = bulk_cnt; > - unsigned long flags; > - depot_stack_handle_t handle = 0; > - > - if (s->flags & SLAB_STORE_USER) > - handle = set_track_prepare(); > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - if (free_debug_processing(s, slab, head, tail, &cnt, addr, handle)) { > - void *prior = slab->freelist; > - > - /* Perform the actual freeing while we still hold the locks */ > - slab->inuse -= cnt; > - set_freepointer(s, tail, prior); > - slab->freelist = head; > - > - /* > - * If the slab is empty, and node's partial list is full, > - * it should be discarded anyway no matter it's on full or > - * partial list. > - */ > - if (slab->inuse == 0 && n->nr_partial >= s->min_partial) > - slab_free = slab; > - > - if (!prior) { > - /* was on full list */ > - remove_full(s, n, slab); > - if (!slab_free) { > - add_partial(n, slab, DEACTIVATE_TO_TAIL); > - stat(s, FREE_ADD_PARTIAL); > - } > - } else if (slab_free) { > - remove_partial(n, slab); > - stat(s, FREE_REMOVE_PARTIAL); > - } > - } > - > - if (slab_free) { > - /* > - * Update the counters while still holding n->list_lock to > - * prevent spurious validation warnings > - */ > - dec_slabs_node(s, slab_nid(slab_free), slab_free->objects); > - } > - > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - if (slab_free) { > - stat(s, FREE_SLAB); > - free_slab(s, slab_free); > - } > -} > - > -/* > - * Slow path handling. This may still be called frequently since objects > - * have a longer lifetime than the cpu slabs in most processing loads. > - * > - * So we still attempt to reduce cache line usage. Just take the slab > - * lock and free the item. If there is no additional partial slab > - * handling required then we can return immediately. > - */ > -static void __slab_free(struct kmem_cache *s, struct slab *slab, > - void *head, void *tail, int cnt, > - unsigned long addr) > - > -{ > - void *prior; > - int was_frozen; > - struct slab new; > - unsigned long counters; > - struct kmem_cache_node *n = NULL; > - unsigned long flags; > - > - stat(s, FREE_SLOWPATH); > - > - if (kfence_free(head)) > - return; > - > - if (IS_ENABLED(CONFIG_SLUB_TINY) || kmem_cache_debug(s)) { > - free_to_partial_list(s, slab, head, tail, cnt, addr); > - return; > - } > - > - do { > - if (unlikely(n)) { > - spin_unlock_irqrestore(&n->list_lock, flags); > - n = NULL; > - } > - prior = slab->freelist; > - counters = slab->counters; > - set_freepointer(s, tail, prior); > - new.counters = counters; > - was_frozen = new.frozen; > - new.inuse -= cnt; > - if ((!new.inuse || !prior) && !was_frozen) { > - > - if (kmem_cache_has_cpu_partial(s) && !prior) { > - > - /* > - * Slab was on no list before and will be > - * partially empty > - * We can defer the list move and instead > - * freeze it. > - */ > - new.frozen = 1; > - > - } else { /* Needs to be taken off a list */ > - > - n = get_node(s, slab_nid(slab)); > - /* > - * Speculatively acquire the list_lock. > - * If the cmpxchg does not succeed then we may > - * drop the list_lock without any processing. > - * > - * Otherwise the list_lock will synchronize with > - * other processors updating the list of slabs. > - */ > - spin_lock_irqsave(&n->list_lock, flags); > - > - } > - } > - > - } while (!cmpxchg_double_slab(s, slab, > - prior, counters, > - head, new.counters, > - "__slab_free")); > - > - if (likely(!n)) { > - > - if (likely(was_frozen)) { > - /* > - * The list lock was not taken therefore no list > - * activity can be necessary. > - */ > - stat(s, FREE_FROZEN); > - } else if (new.frozen) { > - /* > - * If we just froze the slab then put it onto the > - * per cpu partial list. > - */ > - put_cpu_partial(s, slab, 1); > - stat(s, CPU_PARTIAL_FREE); > - } > - > - return; > - } > - > - if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) > - goto slab_empty; > - > - /* > - * Objects left in the slab. If it was not on the partial list before > - * then add it. > - */ > - if (!kmem_cache_has_cpu_partial(s) && unlikely(!prior)) { > - remove_full(s, n, slab); > - add_partial(n, slab, DEACTIVATE_TO_TAIL); > - stat(s, FREE_ADD_PARTIAL); > - } > - spin_unlock_irqrestore(&n->list_lock, flags); > - return; > - > -slab_empty: > - if (prior) { > - /* > - * Slab on the partial list. > - */ > - remove_partial(n, slab); > - stat(s, FREE_REMOVE_PARTIAL); > - } else { > - /* Slab must be on the full list */ > - remove_full(s, n, slab); > - } > - > - spin_unlock_irqrestore(&n->list_lock, flags); > - stat(s, FREE_SLAB); > - discard_slab(s, slab); > -} > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Fastpath with forced inlining to produce a kfree and kmem_cache_free that > - * can perform fastpath freeing without additional function calls. > - * > - * The fastpath is only possible if we are freeing to the current cpu slab > - * of this processor. This typically the case if we have just allocated > - * the item before. > - * > - * If fastpath is not possible then fall back to __slab_free where we deal > - * with all sorts of special processing. > - * > - * Bulk free of a freelist with several objects (all pointing to the > - * same slab) possible by specifying head and tail ptr, plus objects > - * count (cnt). Bulk free indicated by tail pointer being set. > - */ > -static __always_inline void do_slab_free(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, > - int cnt, unsigned long addr) > -{ > - void *tail_obj = tail ? : head; > - struct kmem_cache_cpu *c; > - unsigned long tid; > - void **freelist; > - > -redo: > - /* > - * Determine the currently cpus per cpu slab. > - * The cpu may change afterward. However that does not matter since > - * data is retrieved via this pointer. If we are on the same cpu > - * during the cmpxchg then the free will succeed. > - */ > - c = raw_cpu_ptr(s->cpu_slab); > - tid = READ_ONCE(c->tid); > - > - /* Same with comment on barrier() in slab_alloc_node() */ > - barrier(); > - > - if (unlikely(slab != c->slab)) { > - __slab_free(s, slab, head, tail_obj, cnt, addr); > - return; > - } > - > - if (USE_LOCKLESS_FAST_PATH()) { > - freelist = READ_ONCE(c->freelist); > - > - set_freepointer(s, tail_obj, freelist); > - > - if (unlikely(!this_cpu_cmpxchg_double( > - s->cpu_slab->freelist, s->cpu_slab->tid, > - freelist, tid, > - head, next_tid(tid)))) { > - > - note_cmpxchg_failure("slab_free", s, tid); > - goto redo; > - } > - } else { > - /* Update the free list under the local lock */ > - local_lock(&s->cpu_slab->lock); > - c = this_cpu_ptr(s->cpu_slab); > - if (unlikely(slab != c->slab)) { > - local_unlock(&s->cpu_slab->lock); > - goto redo; > - } > - tid = c->tid; > - freelist = c->freelist; > - > - set_freepointer(s, tail_obj, freelist); > - c->freelist = head; > - c->tid = next_tid(tid); > - > - local_unlock(&s->cpu_slab->lock); > - } > - stat(s, FREE_FASTPATH); > -} > -#else /* CONFIG_SLUB_TINY */ > -static void do_slab_free(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, > - int cnt, unsigned long addr) > -{ > - void *tail_obj = tail ? : head; > - > - __slab_free(s, slab, head, tail_obj, cnt, addr); > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -static __fastpath_inline void slab_free(struct kmem_cache *s, struct slab *slab, > - void *head, void *tail, void **p, int cnt, > - unsigned long addr) > -{ > - memcg_slab_free_hook(s, slab, p, cnt); > - /* > - * With KASAN enabled slab_free_freelist_hook modifies the freelist > - * to remove objects, whose reuse must be delayed. > - */ > - if (slab_free_freelist_hook(s, &head, &tail, &cnt)) > - do_slab_free(s, slab, head, tail, cnt, addr); > -} > - > -#ifdef CONFIG_KASAN_GENERIC > -void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr) > -{ > - do_slab_free(cache, virt_to_slab(x), x, NULL, 1, addr); > -} > -#endif > - > -void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller) > -{ > - slab_free(s, virt_to_slab(x), x, NULL, &x, 1, caller); > -} > - > -void kmem_cache_free(struct kmem_cache *s, void *x) > -{ > - s = cache_from_obj(s, x); > - if (!s) > - return; > - trace_kmem_cache_free(_RET_IP_, x, s); > - slab_free(s, virt_to_slab(x), x, NULL, &x, 1, _RET_IP_); > -} > -EXPORT_SYMBOL(kmem_cache_free); > - > -struct detached_freelist { > - struct slab *slab; > - void *tail; > - void *freelist; > - int cnt; > - struct kmem_cache *s; > -}; > - > -/* > - * This function progressively scans the array with free objects (with > - * a limited look ahead) and extract objects belonging to the same > - * slab. It builds a detached freelist directly within the given > - * slab/objects. This can happen without any need for > - * synchronization, because the objects are owned by running process. > - * The freelist is build up as a single linked list in the objects. > - * The idea is, that this detached freelist can then be bulk > - * transferred to the real freelist(s), but only requiring a single > - * synchronization primitive. Look ahead in the array is limited due > - * to performance reasons. > - */ > -static inline > -int build_detached_freelist(struct kmem_cache *s, size_t size, > - void **p, struct detached_freelist *df) > -{ > - int lookahead = 3; > - void *object; > - struct folio *folio; > - size_t same; > - > - object = p[--size]; > - folio = virt_to_folio(object); > - if (!s) { > - /* Handle kalloc'ed objects */ > - if (unlikely(!folio_test_slab(folio))) { > - free_large_kmalloc(folio, object); > - df->slab = NULL; > - return size; > - } > - /* Derive kmem_cache from object */ > - df->slab = folio_slab(folio); > - df->s = df->slab->slab_cache; > - } else { > - df->slab = folio_slab(folio); > - df->s = cache_from_obj(s, object); /* Support for memcg */ > - } > - > - /* Start new detached freelist */ > - df->tail = object; > - df->freelist = object; > - df->cnt = 1; > - > - if (is_kfence_address(object)) > - return size; > - > - set_freepointer(df->s, object, NULL); > - > - same = size; > - while (size) { > - object = p[--size]; > - /* df->slab is always set at this point */ > - if (df->slab == virt_to_slab(object)) { > - /* Opportunity build freelist */ > - set_freepointer(df->s, object, df->freelist); > - df->freelist = object; > - df->cnt++; > - same--; > - if (size != same) > - swap(p[size], p[same]); > - continue; > - } > - > - /* Limit look ahead search */ > - if (!--lookahead) > - break; > - } > - > - return same; > -} > - > -/* Note that interrupts must be enabled when calling this function. */ > -void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p) > -{ > - if (!size) > - return; > - > - do { > - struct detached_freelist df; > - > - size = build_detached_freelist(s, size, p, &df); > - if (!df.slab) > - continue; > - > - slab_free(df.s, df.slab, df.freelist, df.tail, &p[size], df.cnt, > - _RET_IP_); > - } while (likely(size)); > -} > -EXPORT_SYMBOL(kmem_cache_free_bulk); > - > -#ifndef CONFIG_SLUB_TINY > -static inline int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, > - size_t size, void **p, struct obj_cgroup *objcg) > -{ > - struct kmem_cache_cpu *c; > - unsigned long irqflags; > - int i; > - > - /* > - * Drain objects in the per cpu slab, while disabling local > - * IRQs, which protects against PREEMPT and interrupts > - * handlers invoking normal fastpath. > - */ > - c = slub_get_cpu_ptr(s->cpu_slab); > - local_lock_irqsave(&s->cpu_slab->lock, irqflags); > - > - for (i = 0; i < size; i++) { > - void *object = kfence_alloc(s, s->object_size, flags); > - > - if (unlikely(object)) { > - p[i] = object; > - continue; > - } > - > - object = c->freelist; > - if (unlikely(!object)) { > - /* > - * We may have removed an object from c->freelist using > - * the fastpath in the previous iteration; in that case, > - * c->tid has not been bumped yet. > - * Since ___slab_alloc() may reenable interrupts while > - * allocating memory, we should bump c->tid now. > - */ > - c->tid = next_tid(c->tid); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, irqflags); > - > - /* > - * Invoking slow path likely have side-effect > - * of re-populating per CPU c->freelist > - */ > - p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE, > - _RET_IP_, c, s->object_size); > - if (unlikely(!p[i])) > - goto error; > - > - c = this_cpu_ptr(s->cpu_slab); > - maybe_wipe_obj_freeptr(s, p[i]); > - > - local_lock_irqsave(&s->cpu_slab->lock, irqflags); > - > - continue; /* goto for-loop */ > - } > - c->freelist = get_freepointer(s, object); > - p[i] = object; > - maybe_wipe_obj_freeptr(s, p[i]); > - } > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, irqflags); > - slub_put_cpu_ptr(s->cpu_slab); > - > - return i; > - > -error: > - slub_put_cpu_ptr(s->cpu_slab); > - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); > - kmem_cache_free_bulk(s, i, p); > - return 0; > - > -} > -#else /* CONFIG_SLUB_TINY */ > -static int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, > - size_t size, void **p, struct obj_cgroup *objcg) > -{ > - int i; > - > - for (i = 0; i < size; i++) { > - void *object = kfence_alloc(s, s->object_size, flags); > - > - if (unlikely(object)) { > - p[i] = object; > - continue; > - } > - > - p[i] = __slab_alloc_node(s, flags, NUMA_NO_NODE, > - _RET_IP_, s->object_size); > - if (unlikely(!p[i])) > - goto error; > - > - maybe_wipe_obj_freeptr(s, p[i]); > - } > - > - return i; > - > -error: > - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); > - kmem_cache_free_bulk(s, i, p); > - return 0; > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -/* Note that interrupts must be enabled when calling this function. */ > -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, > - void **p) > -{ > - int i; > - struct obj_cgroup *objcg = NULL; > - > - if (!size) > - return 0; > - > - /* memcg and kmem_cache debug support */ > - s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); > - if (unlikely(!s)) > - return 0; > - > - i = __kmem_cache_alloc_bulk(s, flags, size, p, objcg); > - > - /* > - * memcg and kmem_cache debug support and memory initialization. > - * Done outside of the IRQ disabled fastpath loop. > - */ > - if (i != 0) > - slab_post_alloc_hook(s, objcg, flags, size, p, > - slab_want_init_on_alloc(flags, s), s->object_size); > - return i; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_bulk); > - > - > -/* > - * Object placement in a slab is made very easy because we always start at > - * offset 0. If we tune the size of the object to the alignment then we can > - * get the required alignment by putting one properly sized object after > - * another. > - * > - * Notice that the allocation order determines the sizes of the per cpu > - * caches. Each processor has always one slab available for allocations. > - * Increasing the allocation order reduces the number of times that slabs > - * must be moved on and off the partial lists and is therefore a factor in > - * locking overhead. > - */ > - > -/* > - * Minimum / Maximum order of slab pages. This influences locking overhead > - * and slab fragmentation. A higher order reduces the number of partial slabs > - * and increases the number of allocations possible without having to > - * take the list_lock. > - */ > -static unsigned int slub_min_order; > -static unsigned int slub_max_order = > - IS_ENABLED(CONFIG_SLUB_TINY) ? 1 : PAGE_ALLOC_COSTLY_ORDER; > -static unsigned int slub_min_objects; > - > -/* > - * Calculate the order of allocation given an slab object size. > - * > - * The order of allocation has significant impact on performance and other > - * system components. Generally order 0 allocations should be preferred since > - * order 0 does not cause fragmentation in the page allocator. Larger objects > - * be problematic to put into order 0 slabs because there may be too much > - * unused space left. We go to a higher order if more than 1/16th of the slab > - * would be wasted. > - * > - * In order to reach satisfactory performance we must ensure that a minimum > - * number of objects is in one slab. Otherwise we may generate too much > - * activity on the partial lists which requires taking the list_lock. This is > - * less a concern for large slabs though which are rarely used. > - * > - * slub_max_order specifies the order where we begin to stop considering the > - * number of objects in a slab as critical. If we reach slub_max_order then > - * we try to keep the page order as low as possible. So we accept more waste > - * of space in favor of a small page order. > - * > - * Higher order allocations also allow the placement of more objects in a > - * slab and thereby reduce object handling overhead. If the user has > - * requested a higher minimum order then we start with that one instead of > - * the smallest order which will fit the object. > - */ > -static inline unsigned int calc_slab_order(unsigned int size, > - unsigned int min_objects, unsigned int max_order, > - unsigned int fract_leftover) > -{ > - unsigned int min_order = slub_min_order; > - unsigned int order; > - > - if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE) > - return get_order(size * MAX_OBJS_PER_PAGE) - 1; > - > - for (order = max(min_order, (unsigned int)get_order(min_objects * size)); > - order <= max_order; order++) { > - > - unsigned int slab_size = (unsigned int)PAGE_SIZE << order; > - unsigned int rem; > - > - rem = slab_size % size; > - > - if (rem <= slab_size / fract_leftover) > - break; > - } > - > - return order; > -} > - > -static inline int calculate_order(unsigned int size) > -{ > - unsigned int order; > - unsigned int min_objects; > - unsigned int max_objects; > - unsigned int nr_cpus; > - > - /* > - * Attempt to find best configuration for a slab. This > - * works by first attempting to generate a layout with > - * the best configuration and backing off gradually. > - * > - * First we increase the acceptable waste in a slab. Then > - * we reduce the minimum objects required in a slab. > - */ > - min_objects = slub_min_objects; > - if (!min_objects) { > - /* > - * Some architectures will only update present cpus when > - * onlining them, so don't trust the number if it's just 1. But > - * we also don't want to use nr_cpu_ids always, as on some other > - * architectures, there can be many possible cpus, but never > - * onlined. Here we compromise between trying to avoid too high > - * order on systems that appear larger than they are, and too > - * low order on systems that appear smaller than they are. > - */ > - nr_cpus = num_present_cpus(); > - if (nr_cpus <= 1) > - nr_cpus = nr_cpu_ids; > - min_objects = 4 * (fls(nr_cpus) + 1); > - } > - max_objects = order_objects(slub_max_order, size); > - min_objects = min(min_objects, max_objects); > - > - while (min_objects > 1) { > - unsigned int fraction; > - > - fraction = 16; > - while (fraction >= 4) { > - order = calc_slab_order(size, min_objects, > - slub_max_order, fraction); > - if (order <= slub_max_order) > - return order; > - fraction /= 2; > - } > - min_objects--; > - } > - > - /* > - * We were unable to place multiple objects in a slab. Now > - * lets see if we can place a single object there. > - */ > - order = calc_slab_order(size, 1, slub_max_order, 1); > - if (order <= slub_max_order) > - return order; > - > - /* > - * Doh this slab cannot be placed using slub_max_order. > - */ > - order = calc_slab_order(size, 1, MAX_ORDER, 1); > - if (order < MAX_ORDER) > - return order; > - return -ENOSYS; > -} > - > -static void > -init_kmem_cache_node(struct kmem_cache_node *n) > -{ > - n->nr_partial = 0; > - spin_lock_init(&n->list_lock); > - INIT_LIST_HEAD(&n->partial); > -#ifdef CONFIG_SLUB_DEBUG > - atomic_long_set(&n->nr_slabs, 0); > - atomic_long_set(&n->total_objects, 0); > - INIT_LIST_HEAD(&n->full); > -#endif > -} > - > -#ifndef CONFIG_SLUB_TINY > -static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) > -{ > - BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE < > - NR_KMALLOC_TYPES * KMALLOC_SHIFT_HIGH * > - sizeof(struct kmem_cache_cpu)); > - > - /* > - * Must align to double word boundary for the double cmpxchg > - * instructions to work; see __pcpu_double_call_return_bool(). > - */ > - s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu), > - 2 * sizeof(void *)); > - > - if (!s->cpu_slab) > - return 0; > - > - init_kmem_cache_cpus(s); > - > - return 1; > -} > -#else > -static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) > -{ > - return 1; > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -static struct kmem_cache *kmem_cache_node; > - > -/* > - * No kmalloc_node yet so do it by hand. We know that this is the first > - * slab on the node for this slabcache. There are no concurrent accesses > - * possible. > - * > - * Note that this function only works on the kmem_cache_node > - * when allocating for the kmem_cache_node. This is used for bootstrapping > - * memory on a fresh node that has no slab structures yet. > - */ > -static void early_kmem_cache_node_alloc(int node) > -{ > - struct slab *slab; > - struct kmem_cache_node *n; > - > - BUG_ON(kmem_cache_node->size < sizeof(struct kmem_cache_node)); > - > - slab = new_slab(kmem_cache_node, GFP_NOWAIT, node); > - > - BUG_ON(!slab); > - inc_slabs_node(kmem_cache_node, slab_nid(slab), slab->objects); > - if (slab_nid(slab) != node) { > - pr_err("SLUB: Unable to allocate memory from node %d\n", node); > - pr_err("SLUB: Allocating a useless per node structure in order to be able to continue\n"); > - } > - > - n = slab->freelist; > - BUG_ON(!n); > -#ifdef CONFIG_SLUB_DEBUG > - init_object(kmem_cache_node, n, SLUB_RED_ACTIVE); > - init_tracking(kmem_cache_node, n); > -#endif > - n = kasan_slab_alloc(kmem_cache_node, n, GFP_KERNEL, false); > - slab->freelist = get_freepointer(kmem_cache_node, n); > - slab->inuse = 1; > - kmem_cache_node->node[node] = n; > - init_kmem_cache_node(n); > - inc_slabs_node(kmem_cache_node, node, slab->objects); > - > - /* > - * No locks need to be taken here as it has just been > - * initialized and there is no concurrent access. > - */ > - __add_partial(n, slab, DEACTIVATE_TO_HEAD); > -} > - > -static void free_kmem_cache_nodes(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - s->node[node] = NULL; > - kmem_cache_free(kmem_cache_node, n); > - } > -} > - > -void __kmem_cache_release(struct kmem_cache *s) > -{ > - cache_random_seq_destroy(s); > -#ifndef CONFIG_SLUB_TINY > - free_percpu(s->cpu_slab); > -#endif > - free_kmem_cache_nodes(s); > -} > - > -static int init_kmem_cache_nodes(struct kmem_cache *s) > -{ > - int node; > - > - for_each_node_mask(node, slab_nodes) { > - struct kmem_cache_node *n; > - > - if (slab_state == DOWN) { > - early_kmem_cache_node_alloc(node); > - continue; > - } > - n = kmem_cache_alloc_node(kmem_cache_node, > - GFP_KERNEL, node); > - > - if (!n) { > - free_kmem_cache_nodes(s); > - return 0; > - } > - > - init_kmem_cache_node(n); > - s->node[node] = n; > - } > - return 1; > -} > - > -static void set_cpu_partial(struct kmem_cache *s) > -{ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - unsigned int nr_objects; > - > - /* > - * cpu_partial determined the maximum number of objects kept in the > - * per cpu partial lists of a processor. > - * > - * Per cpu partial lists mainly contain slabs that just have one > - * object freed. If they are used for allocation then they can be > - * filled up again with minimal effort. The slab will never hit the > - * per node partial lists and therefore no locking will be required. > - * > - * For backwards compatibility reasons, this is determined as number > - * of objects, even though we now limit maximum number of pages, see > - * slub_set_cpu_partial() > - */ > - if (!kmem_cache_has_cpu_partial(s)) > - nr_objects = 0; > - else if (s->size >= PAGE_SIZE) > - nr_objects = 6; > - else if (s->size >= 1024) > - nr_objects = 24; > - else if (s->size >= 256) > - nr_objects = 52; > - else > - nr_objects = 120; > - > - slub_set_cpu_partial(s, nr_objects); > -#endif > -} > - > -/* > - * calculate_sizes() determines the order and the distribution of data within > - * a slab object. > - */ > -static int calculate_sizes(struct kmem_cache *s) > -{ > - slab_flags_t flags = s->flags; > - unsigned int size = s->object_size; > - unsigned int order; > - > - /* > - * Round up object size to the next word boundary. We can only > - * place the free pointer at word boundaries and this determines > - * the possible location of the free pointer. > - */ > - size = ALIGN(size, sizeof(void *)); > - > -#ifdef CONFIG_SLUB_DEBUG > - /* > - * Determine if we can poison the object itself. If the user of > - * the slab may touch the object after free or before allocation > - * then we should never poison the object itself. > - */ > - if ((flags & SLAB_POISON) && !(flags & SLAB_TYPESAFE_BY_RCU) && > - !s->ctor) > - s->flags |= __OBJECT_POISON; > - else > - s->flags &= ~__OBJECT_POISON; > - > - > - /* > - * If we are Redzoning then check if there is some space between the > - * end of the object and the free pointer. If not then add an > - * additional word to have some bytes to store Redzone information. > - */ > - if ((flags & SLAB_RED_ZONE) && size == s->object_size) > - size += sizeof(void *); > -#endif > - > - /* > - * With that we have determined the number of bytes in actual use > - * by the object and redzoning. > - */ > - s->inuse = size; > - > - if (slub_debug_orig_size(s) || > - (flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) || > - ((flags & SLAB_RED_ZONE) && s->object_size < sizeof(void *)) || > - s->ctor) { > - /* > - * Relocate free pointer after the object if it is not > - * permitted to overwrite the first word of the object on > - * kmem_cache_free. > - * > - * This is the case if we do RCU, have a constructor or > - * destructor, are poisoning the objects, or are > - * redzoning an object smaller than sizeof(void *). > - * > - * The assumption that s->offset >= s->inuse means free > - * pointer is outside of the object is used in the > - * freeptr_outside_object() function. If that is no > - * longer true, the function needs to be modified. > - */ > - s->offset = size; > - size += sizeof(void *); > - } else { > - /* > - * Store freelist pointer near middle of object to keep > - * it away from the edges of the object to avoid small > - * sized over/underflows from neighboring allocations. > - */ > - s->offset = ALIGN_DOWN(s->object_size / 2, sizeof(void *)); > - } > - > -#ifdef CONFIG_SLUB_DEBUG > - if (flags & SLAB_STORE_USER) { > - /* > - * Need to store information about allocs and frees after > - * the object. > - */ > - size += 2 * sizeof(struct track); > - > - /* Save the original kmalloc request size */ > - if (flags & SLAB_KMALLOC) > - size += sizeof(unsigned int); > - } > -#endif > - > - kasan_cache_create(s, &size, &s->flags); > -#ifdef CONFIG_SLUB_DEBUG > - if (flags & SLAB_RED_ZONE) { > - /* > - * Add some empty padding so that we can catch > - * overwrites from earlier objects rather than let > - * tracking information or the free pointer be > - * corrupted if a user writes before the start > - * of the object. > - */ > - size += sizeof(void *); > - > - s->red_left_pad = sizeof(void *); > - s->red_left_pad = ALIGN(s->red_left_pad, s->align); > - size += s->red_left_pad; > - } > -#endif > - > - /* > - * SLUB stores one object immediately after another beginning from > - * offset 0. In order to align the objects we have to simply size > - * each object to conform to the alignment. > - */ > - size = ALIGN(size, s->align); > - s->size = size; > - s->reciprocal_size = reciprocal_value(size); > - order = calculate_order(size); > - > - if ((int)order < 0) > - return 0; > - > - s->allocflags = 0; > - if (order) > - s->allocflags |= __GFP_COMP; > - > - if (s->flags & SLAB_CACHE_DMA) > - s->allocflags |= GFP_DMA; > - > - if (s->flags & SLAB_CACHE_DMA32) > - s->allocflags |= GFP_DMA32; > - > - if (s->flags & SLAB_RECLAIM_ACCOUNT) > - s->allocflags |= __GFP_RECLAIMABLE; > - > - /* > - * Determine the number of objects per slab > - */ > - s->oo = oo_make(order, size); > - s->min = oo_make(get_order(size), size); > - > - return !!oo_objects(s->oo); > -} > - > -static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags) > -{ > - s->flags = kmem_cache_flags(s->size, flags, s->name); > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - s->random = get_random_long(); > -#endif > - > - if (!calculate_sizes(s)) > - goto error; > - if (disable_higher_order_debug) { > - /* > - * Disable debugging flags that store metadata if the min slab > - * order increased. > - */ > - if (get_order(s->size) > get_order(s->object_size)) { > - s->flags &= ~DEBUG_METADATA_FLAGS; > - s->offset = 0; > - if (!calculate_sizes(s)) > - goto error; > - } > - } > - > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ > - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) > - if (system_has_cmpxchg_double() && (s->flags & SLAB_NO_CMPXCHG) == 0) > - /* Enable fast mode */ > - s->flags |= __CMPXCHG_DOUBLE; > -#endif > - > - /* > - * The larger the object size is, the more slabs we want on the partial > - * list to avoid pounding the page allocator excessively. > - */ > - s->min_partial = min_t(unsigned long, MAX_PARTIAL, ilog2(s->size) / 2); > - s->min_partial = max_t(unsigned long, MIN_PARTIAL, s->min_partial); > - > - set_cpu_partial(s); > - > -#ifdef CONFIG_NUMA > - s->remote_node_defrag_ratio = 1000; > -#endif > - > - /* Initialize the pre-computed randomized freelist if slab is up */ > - if (slab_state >= UP) { > - if (init_cache_random_seq(s)) > - goto error; > - } > - > - if (!init_kmem_cache_nodes(s)) > - goto error; > - > - if (alloc_kmem_cache_cpus(s)) > - return 0; > - > -error: > - __kmem_cache_release(s); > - return -EINVAL; > -} > - > -static void list_slab_objects(struct kmem_cache *s, struct slab *slab, > - const char *text) > -{ > -#ifdef CONFIG_SLUB_DEBUG > - void *addr = slab_address(slab); > - void *p; > - > - slab_err(s, slab, text, s->name); > - > - spin_lock(&object_map_lock); > - __fill_map(object_map, s, slab); > - > - for_each_object(p, s, addr, slab->objects) { > - > - if (!test_bit(__obj_to_index(s, addr, p), object_map)) { > - pr_err("Object 0x%p @offset=%tu\n", p, p - addr); > - print_tracking(s, p); > - } > - } > - spin_unlock(&object_map_lock); > -#endif > -} > - > -/* > - * Attempt to free all partial slabs on a node. > - * This is called from __kmem_cache_shutdown(). We must take list_lock > - * because sysfs file might still access partial list after the shutdowning. > - */ > -static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n) > -{ > - LIST_HEAD(discard); > - struct slab *slab, *h; > - > - BUG_ON(irqs_disabled()); > - spin_lock_irq(&n->list_lock); > - list_for_each_entry_safe(slab, h, &n->partial, slab_list) { > - if (!slab->inuse) { > - remove_partial(n, slab); > - list_add(&slab->slab_list, &discard); > - } else { > - list_slab_objects(s, slab, > - "Objects remaining in %s on __kmem_cache_shutdown()"); > - } > - } > - spin_unlock_irq(&n->list_lock); > - > - list_for_each_entry_safe(slab, h, &discard, slab_list) > - discard_slab(s, slab); > -} > - > -bool __kmem_cache_empty(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) > - if (n->nr_partial || slabs_node(s, node)) > - return false; > - return true; > -} > - > -/* > - * Release all resources used by a slab cache. > - */ > -int __kmem_cache_shutdown(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - flush_all_cpus_locked(s); > - /* Attempt to free all objects */ > - for_each_kmem_cache_node(s, node, n) { > - free_partial(s, n); > - if (n->nr_partial || slabs_node(s, node)) > - return 1; > - } > - return 0; > -} > - > -#ifdef CONFIG_PRINTK > -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) > -{ > - void *base; > - int __maybe_unused i; > - unsigned int objnr; > - void *objp; > - void *objp0; > - struct kmem_cache *s = slab->slab_cache; > - struct track __maybe_unused *trackp; > - > - kpp->kp_ptr = object; > - kpp->kp_slab = slab; > - kpp->kp_slab_cache = s; > - base = slab_address(slab); > - objp0 = kasan_reset_tag(object); > -#ifdef CONFIG_SLUB_DEBUG > - objp = restore_red_left(s, objp0); > -#else > - objp = objp0; > -#endif > - objnr = obj_to_index(s, slab, objp); > - kpp->kp_data_offset = (unsigned long)((char *)objp0 - (char *)objp); > - objp = base + s->size * objnr; > - kpp->kp_objp = objp; > - if (WARN_ON_ONCE(objp < base || objp >= base + slab->objects * s->size > - || (objp - base) % s->size) || > - !(s->flags & SLAB_STORE_USER)) > - return; > -#ifdef CONFIG_SLUB_DEBUG > - objp = fixup_red_left(s, objp); > - trackp = get_track(s, objp, TRACK_ALLOC); > - kpp->kp_ret = (void *)trackp->addr; > -#ifdef CONFIG_STACKDEPOT > - { > - depot_stack_handle_t handle; > - unsigned long *entries; > - unsigned int nr_entries; > - > - handle = READ_ONCE(trackp->handle); > - if (handle) { > - nr_entries = stack_depot_fetch(handle, &entries); > - for (i = 0; i < KS_ADDRS_COUNT && i < nr_entries; i++) > - kpp->kp_stack[i] = (void *)entries[i]; > - } > - > - trackp = get_track(s, objp, TRACK_FREE); > - handle = READ_ONCE(trackp->handle); > - if (handle) { > - nr_entries = stack_depot_fetch(handle, &entries); > - for (i = 0; i < KS_ADDRS_COUNT && i < nr_entries; i++) > - kpp->kp_free_stack[i] = (void *)entries[i]; > - } > - } > -#endif > -#endif > -} > -#endif > - > -/******************************************************************** > - * Kmalloc subsystem > - *******************************************************************/ > - > -static int __init setup_slub_min_order(char *str) > -{ > - get_option(&str, (int *)&slub_min_order); > - > - return 1; > -} > - > -__setup("slub_min_order=", setup_slub_min_order); > - > -static int __init setup_slub_max_order(char *str) > -{ > - get_option(&str, (int *)&slub_max_order); > - slub_max_order = min(slub_max_order, (unsigned int)MAX_ORDER - 1); > - > - return 1; > -} > - > -__setup("slub_max_order=", setup_slub_max_order); > - > -static int __init setup_slub_min_objects(char *str) > -{ > - get_option(&str, (int *)&slub_min_objects); > - > - return 1; > -} > - > -__setup("slub_min_objects=", setup_slub_min_objects); > - > -#ifdef CONFIG_HARDENED_USERCOPY > -/* > - * Rejects incorrectly sized objects and objects that are to be copied > - * to/from userspace but do not fall entirely within the containing slab > - * cache's usercopy region. > - * > - * Returns NULL if check passes, otherwise const char * to name of cache > - * to indicate an error. > - */ > -void __check_heap_object(const void *ptr, unsigned long n, > - const struct slab *slab, bool to_user) > -{ > - struct kmem_cache *s; > - unsigned int offset; > - bool is_kfence = is_kfence_address(ptr); > - > - ptr = kasan_reset_tag(ptr); > - > - /* Find object and usable object size. */ > - s = slab->slab_cache; > - > - /* Reject impossible pointers. */ > - if (ptr < slab_address(slab)) > - usercopy_abort("SLUB object not in SLUB page?!", NULL, > - to_user, 0, n); > - > - /* Find offset within object. */ > - if (is_kfence) > - offset = ptr - kfence_object_start(ptr); > - else > - offset = (ptr - slab_address(slab)) % s->size; > - > - /* Adjust for redzone and reject if within the redzone. */ > - if (!is_kfence && kmem_cache_debug_flags(s, SLAB_RED_ZONE)) { > - if (offset < s->red_left_pad) > - usercopy_abort("SLUB object in left red zone", > - s->name, to_user, offset, n); > - offset -= s->red_left_pad; > - } > - > - /* Allow address range falling entirely within usercopy region. */ > - if (offset >= s->useroffset && > - offset - s->useroffset <= s->usersize && > - n <= s->useroffset - offset + s->usersize) > - return; > - > - usercopy_abort("SLUB object", s->name, to_user, offset, n); > -} > -#endif /* CONFIG_HARDENED_USERCOPY */ > - > -#define SHRINK_PROMOTE_MAX 32 > - > -/* > - * kmem_cache_shrink discards empty slabs and promotes the slabs filled > - * up most to the head of the partial lists. New allocations will then > - * fill those up and thus they can be removed from the partial lists. > - * > - * The slabs with the least items are placed last. This results in them > - * being allocated from last increasing the chance that the last objects > - * are freed in them. > - */ > -static int __kmem_cache_do_shrink(struct kmem_cache *s) > -{ > - int node; > - int i; > - struct kmem_cache_node *n; > - struct slab *slab; > - struct slab *t; > - struct list_head discard; > - struct list_head promote[SHRINK_PROMOTE_MAX]; > - unsigned long flags; > - int ret = 0; > - > - for_each_kmem_cache_node(s, node, n) { > - INIT_LIST_HEAD(&discard); > - for (i = 0; i < SHRINK_PROMOTE_MAX; i++) > - INIT_LIST_HEAD(promote + i); > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - /* > - * Build lists of slabs to discard or promote. > - * > - * Note that concurrent frees may occur while we hold the > - * list_lock. slab->inuse here is the upper limit. > - */ > - list_for_each_entry_safe(slab, t, &n->partial, slab_list) { > - int free = slab->objects - slab->inuse; > - > - /* Do not reread slab->inuse */ > - barrier(); > - > - /* We do not keep full slabs on the list */ > - BUG_ON(free <= 0); > - > - if (free == slab->objects) { > - list_move(&slab->slab_list, &discard); > - n->nr_partial--; > - dec_slabs_node(s, node, slab->objects); > - } else if (free <= SHRINK_PROMOTE_MAX) > - list_move(&slab->slab_list, promote + free - 1); > - } > - > - /* > - * Promote the slabs filled up most to the head of the > - * partial list. > - */ > - for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--) > - list_splice(promote + i, &n->partial); > - > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - /* Release empty slabs */ > - list_for_each_entry_safe(slab, t, &discard, slab_list) > - free_slab(s, slab); > - > - if (slabs_node(s, node)) > - ret = 1; > - } > - > - return ret; > -} > - > -int __kmem_cache_shrink(struct kmem_cache *s) > -{ > - flush_all(s); > - return __kmem_cache_do_shrink(s); > -} > - > -static int slab_mem_going_offline_callback(void *arg) > -{ > - struct kmem_cache *s; > - > - mutex_lock(&slab_mutex); > - list_for_each_entry(s, &slab_caches, list) { > - flush_all_cpus_locked(s); > - __kmem_cache_do_shrink(s); > - } > - mutex_unlock(&slab_mutex); > - > - return 0; > -} > - > -static void slab_mem_offline_callback(void *arg) > -{ > - struct memory_notify *marg = arg; > - int offline_node; > - > - offline_node = marg->status_change_nid_normal; > - > - /* > - * If the node still has available memory. we need kmem_cache_node > - * for it yet. > - */ > - if (offline_node < 0) > - return; > - > - mutex_lock(&slab_mutex); > - node_clear(offline_node, slab_nodes); > - /* > - * We no longer free kmem_cache_node structures here, as it would be > - * racy with all get_node() users, and infeasible to protect them with > - * slab_mutex. > - */ > - mutex_unlock(&slab_mutex); > -} > - > -static int slab_mem_going_online_callback(void *arg) > -{ > - struct kmem_cache_node *n; > - struct kmem_cache *s; > - struct memory_notify *marg = arg; > - int nid = marg->status_change_nid_normal; > - int ret = 0; > - > - /* > - * If the node's memory is already available, then kmem_cache_node is > - * already created. Nothing to do. > - */ > - if (nid < 0) > - return 0; > - > - /* > - * We are bringing a node online. No memory is available yet. We must > - * allocate a kmem_cache_node structure in order to bring the node > - * online. > - */ > - mutex_lock(&slab_mutex); > - list_for_each_entry(s, &slab_caches, list) { > - /* > - * The structure may already exist if the node was previously > - * onlined and offlined. > - */ > - if (get_node(s, nid)) > - continue; > - /* > - * XXX: kmem_cache_alloc_node will fallback to other nodes > - * since memory is not yet available from the node that > - * is brought up. > - */ > - n = kmem_cache_alloc(kmem_cache_node, GFP_KERNEL); > - if (!n) { > - ret = -ENOMEM; > - goto out; > - } > - init_kmem_cache_node(n); > - s->node[nid] = n; > - } > - /* > - * Any cache created after this point will also have kmem_cache_node > - * initialized for the new node. > - */ > - node_set(nid, slab_nodes); > -out: > - mutex_unlock(&slab_mutex); > - return ret; > -} > - > -static int slab_memory_callback(struct notifier_block *self, > - unsigned long action, void *arg) > -{ > - int ret = 0; > - > - switch (action) { > - case MEM_GOING_ONLINE: > - ret = slab_mem_going_online_callback(arg); > - break; > - case MEM_GOING_OFFLINE: > - ret = slab_mem_going_offline_callback(arg); > - break; > - case MEM_OFFLINE: > - case MEM_CANCEL_ONLINE: > - slab_mem_offline_callback(arg); > - break; > - case MEM_ONLINE: > - case MEM_CANCEL_OFFLINE: > - break; > - } > - if (ret) > - ret = notifier_from_errno(ret); > - else > - ret = NOTIFY_OK; > - return ret; > -} > - > -/******************************************************************** > - * Basic setup of slabs > - *******************************************************************/ > - > -/* > - * Used for early kmem_cache structures that were allocated using > - * the page allocator. Allocate them properly then fix up the pointers > - * that may be pointing to the wrong kmem_cache structure. > - */ > - > -static struct kmem_cache * __init bootstrap(struct kmem_cache *static_cache) > -{ > - int node; > - struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); > - struct kmem_cache_node *n; > - > - memcpy(s, static_cache, kmem_cache->object_size); > - > - /* > - * This runs very early, and only the boot processor is supposed to be > - * up. Even if it weren't true, IRQs are not up so we couldn't fire > - * IPIs around. > - */ > - __flush_cpu_slab(s, smp_processor_id()); > - for_each_kmem_cache_node(s, node, n) { > - struct slab *p; > - > - list_for_each_entry(p, &n->partial, slab_list) > - p->slab_cache = s; > - > -#ifdef CONFIG_SLUB_DEBUG > - list_for_each_entry(p, &n->full, slab_list) > - p->slab_cache = s; > -#endif > - } > - list_add(&s->list, &slab_caches); > - return s; > -} > - > -void __init kmem_cache_init(void) > -{ > - static __initdata struct kmem_cache boot_kmem_cache, > - boot_kmem_cache_node; > - int node; > - > - if (debug_guardpage_minorder()) > - slub_max_order = 0; > - > - /* Print slub debugging pointers without hashing */ > - if (__slub_debug_enabled()) > - no_hash_pointers_enable(NULL); > - > - kmem_cache_node = &boot_kmem_cache_node; > - kmem_cache = &boot_kmem_cache; > - > - /* > - * Initialize the nodemask for which we will allocate per node > - * structures. Here we don't need taking slab_mutex yet. > - */ > - for_each_node_state(node, N_NORMAL_MEMORY) > - node_set(node, slab_nodes); > - > - create_boot_cache(kmem_cache_node, "kmem_cache_node", > - sizeof(struct kmem_cache_node), SLAB_HWCACHE_ALIGN, 0, 0); > - > - hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI); > - > - /* Able to allocate the per node structures */ > - slab_state = PARTIAL; > - > - create_boot_cache(kmem_cache, "kmem_cache", > - offsetof(struct kmem_cache, node) + > - nr_node_ids * sizeof(struct kmem_cache_node *), > - SLAB_HWCACHE_ALIGN, 0, 0); > - > - kmem_cache = bootstrap(&boot_kmem_cache); > - kmem_cache_node = bootstrap(&boot_kmem_cache_node); > - > - /* Now we can use the kmem_cache to allocate kmalloc slabs */ > - setup_kmalloc_cache_index_table(); > - create_kmalloc_caches(0); > - > - /* Setup random freelists for each cache */ > - init_freelist_randomization(); > - > - cpuhp_setup_state_nocalls(CPUHP_SLUB_DEAD, "slub:dead", NULL, > - slub_cpu_dead); > - > - pr_info("SLUB: HWalign=%d, Order=%u-%u, MinObjects=%u, CPUs=%u, Nodes=%u\n", > - cache_line_size(), > - slub_min_order, slub_max_order, slub_min_objects, > - nr_cpu_ids, nr_node_ids); > -} > - > -void __init kmem_cache_init_late(void) > -{ > -#ifndef CONFIG_SLUB_TINY > - flushwq = alloc_workqueue("slub_flushwq", WQ_MEM_RECLAIM, 0); > - WARN_ON(!flushwq); > -#endif > -} > - > -struct kmem_cache * > -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > - slab_flags_t flags, void (*ctor)(void *)) > -{ > - struct kmem_cache *s; > - > - s = find_mergeable(size, align, flags, name, ctor); > - if (s) { > - if (sysfs_slab_alias(s, name)) > - return NULL; > - > - s->refcount++; > - > - /* > - * Adjust the object sizes so that we clear > - * the complete object on kzalloc. > - */ > - s->object_size = max(s->object_size, size); > - s->inuse = max(s->inuse, ALIGN(size, sizeof(void *))); > - } > - > - return s; > -} > - > -int __kmem_cache_create(struct kmem_cache *s, slab_flags_t flags) > -{ > - int err; > - > - err = kmem_cache_open(s, flags); > - if (err) > - return err; > - > - /* Mutex is not taken during early boot */ > - if (slab_state <= UP) > - return 0; > - > - err = sysfs_slab_add(s); > - if (err) { > - __kmem_cache_release(s); > - return err; > - } > - > - if (s->flags & SLAB_STORE_USER) > - debugfs_slab_add(s); > - > - return 0; > -} > - > -#ifdef SLAB_SUPPORTS_SYSFS > -static int count_inuse(struct slab *slab) > -{ > - return slab->inuse; > -} > - > -static int count_total(struct slab *slab) > -{ > - return slab->objects; > -} > -#endif > - > -#ifdef CONFIG_SLUB_DEBUG > -static void validate_slab(struct kmem_cache *s, struct slab *slab, > - unsigned long *obj_map) > -{ > - void *p; > - void *addr = slab_address(slab); > - > - if (!check_slab(s, slab) || !on_freelist(s, slab, NULL)) > - return; > - > - /* Now we know that a valid freelist exists */ > - __fill_map(obj_map, s, slab); > - for_each_object(p, s, addr, slab->objects) { > - u8 val = test_bit(__obj_to_index(s, addr, p), obj_map) ? > - SLUB_RED_INACTIVE : SLUB_RED_ACTIVE; > - > - if (!check_object(s, slab, p, val)) > - break; > - } > -} > - > -static int validate_slab_node(struct kmem_cache *s, > - struct kmem_cache_node *n, unsigned long *obj_map) > -{ > - unsigned long count = 0; > - struct slab *slab; > - unsigned long flags; > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - list_for_each_entry(slab, &n->partial, slab_list) { > - validate_slab(s, slab, obj_map); > - count++; > - } > - if (count != n->nr_partial) { > - pr_err("SLUB %s: %ld partial slabs counted but counter=%ld\n", > - s->name, count, n->nr_partial); > - slab_add_kunit_errors(); > - } > - > - if (!(s->flags & SLAB_STORE_USER)) > - goto out; > - > - list_for_each_entry(slab, &n->full, slab_list) { > - validate_slab(s, slab, obj_map); > - count++; > - } > - if (count != atomic_long_read(&n->nr_slabs)) { > - pr_err("SLUB: %s %ld slabs counted but counter=%ld\n", > - s->name, count, atomic_long_read(&n->nr_slabs)); > - slab_add_kunit_errors(); > - } > - > -out: > - spin_unlock_irqrestore(&n->list_lock, flags); > - return count; > -} > - > -long validate_slab_cache(struct kmem_cache *s) > -{ > - int node; > - unsigned long count = 0; > - struct kmem_cache_node *n; > - unsigned long *obj_map; > - > - obj_map = bitmap_alloc(oo_objects(s->oo), GFP_KERNEL); > - if (!obj_map) > - return -ENOMEM; > - > - flush_all(s); > - for_each_kmem_cache_node(s, node, n) > - count += validate_slab_node(s, n, obj_map); > - > - bitmap_free(obj_map); > - > - return count; > -} > -EXPORT_SYMBOL(validate_slab_cache); > - > -#ifdef CONFIG_DEBUG_FS > -/* > - * Generate lists of code addresses where slabcache objects are allocated > - * and freed. > - */ > - > -struct location { > - depot_stack_handle_t handle; > - unsigned long count; > - unsigned long addr; > - unsigned long waste; > - long long sum_time; > - long min_time; > - long max_time; > - long min_pid; > - long max_pid; > - DECLARE_BITMAP(cpus, NR_CPUS); > - nodemask_t nodes; > -}; > - > -struct loc_track { > - unsigned long max; > - unsigned long count; > - struct location *loc; > - loff_t idx; > -}; > - > -static struct dentry *slab_debugfs_root; > - > -static void free_loc_track(struct loc_track *t) > -{ > - if (t->max) > - free_pages((unsigned long)t->loc, > - get_order(sizeof(struct location) * t->max)); > -} > - > -static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags) > -{ > - struct location *l; > - int order; > - > - order = get_order(sizeof(struct location) * max); > - > - l = (void *)__get_free_pages(flags, order); > - if (!l) > - return 0; > - > - if (t->count) { > - memcpy(l, t->loc, sizeof(struct location) * t->count); > - free_loc_track(t); > - } > - t->max = max; > - t->loc = l; > - return 1; > -} > - > -static int add_location(struct loc_track *t, struct kmem_cache *s, > - const struct track *track, > - unsigned int orig_size) > -{ > - long start, end, pos; > - struct location *l; > - unsigned long caddr, chandle, cwaste; > - unsigned long age = jiffies - track->when; > - depot_stack_handle_t handle = 0; > - unsigned int waste = s->object_size - orig_size; > - > -#ifdef CONFIG_STACKDEPOT > - handle = READ_ONCE(track->handle); > -#endif > - start = -1; > - end = t->count; > - > - for ( ; ; ) { > - pos = start + (end - start + 1) / 2; > - > - /* > - * There is nothing at "end". If we end up there > - * we need to add something to before end. > - */ > - if (pos == end) > - break; > - > - l = &t->loc[pos]; > - caddr = l->addr; > - chandle = l->handle; > - cwaste = l->waste; > - if ((track->addr == caddr) && (handle == chandle) && > - (waste == cwaste)) { > - > - l->count++; > - if (track->when) { > - l->sum_time += age; > - if (age < l->min_time) > - l->min_time = age; > - if (age > l->max_time) > - l->max_time = age; > - > - if (track->pid < l->min_pid) > - l->min_pid = track->pid; > - if (track->pid > l->max_pid) > - l->max_pid = track->pid; > - > - cpumask_set_cpu(track->cpu, > - to_cpumask(l->cpus)); > - } > - node_set(page_to_nid(virt_to_page(track)), l->nodes); > - return 1; > - } > - > - if (track->addr < caddr) > - end = pos; > - else if (track->addr == caddr && handle < chandle) > - end = pos; > - else if (track->addr == caddr && handle == chandle && > - waste < cwaste) > - end = pos; > - else > - start = pos; > - } > - > - /* > - * Not found. Insert new tracking element. > - */ > - if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC)) > - return 0; > - > - l = t->loc + pos; > - if (pos < t->count) > - memmove(l + 1, l, > - (t->count - pos) * sizeof(struct location)); > - t->count++; > - l->count = 1; > - l->addr = track->addr; > - l->sum_time = age; > - l->min_time = age; > - l->max_time = age; > - l->min_pid = track->pid; > - l->max_pid = track->pid; > - l->handle = handle; > - l->waste = waste; > - cpumask_clear(to_cpumask(l->cpus)); > - cpumask_set_cpu(track->cpu, to_cpumask(l->cpus)); > - nodes_clear(l->nodes); > - node_set(page_to_nid(virt_to_page(track)), l->nodes); > - return 1; > -} > - > -static void process_slab(struct loc_track *t, struct kmem_cache *s, > - struct slab *slab, enum track_item alloc, > - unsigned long *obj_map) > -{ > - void *addr = slab_address(slab); > - bool is_alloc = (alloc == TRACK_ALLOC); > - void *p; > - > - __fill_map(obj_map, s, slab); > - > - for_each_object(p, s, addr, slab->objects) > - if (!test_bit(__obj_to_index(s, addr, p), obj_map)) > - add_location(t, s, get_track(s, p, alloc), > - is_alloc ? get_orig_size(s, p) : > - s->object_size); > -} > -#endif /* CONFIG_DEBUG_FS */ > -#endif /* CONFIG_SLUB_DEBUG */ > - > -#ifdef SLAB_SUPPORTS_SYSFS > -enum slab_stat_type { > - SL_ALL, /* All slabs */ > - SL_PARTIAL, /* Only partially allocated slabs */ > - SL_CPU, /* Only slabs used for cpu caches */ > - SL_OBJECTS, /* Determine allocated objects not slabs */ > - SL_TOTAL /* Determine object capacity not slabs */ > -}; > - > -#define SO_ALL (1 << SL_ALL) > -#define SO_PARTIAL (1 << SL_PARTIAL) > -#define SO_CPU (1 << SL_CPU) > -#define SO_OBJECTS (1 << SL_OBJECTS) > -#define SO_TOTAL (1 << SL_TOTAL) > - > -static ssize_t show_slab_objects(struct kmem_cache *s, > - char *buf, unsigned long flags) > -{ > - unsigned long total = 0; > - int node; > - int x; > - unsigned long *nodes; > - int len = 0; > - > - nodes = kcalloc(nr_node_ids, sizeof(unsigned long), GFP_KERNEL); > - if (!nodes) > - return -ENOMEM; > - > - if (flags & SO_CPU) { > - int cpu; > - > - for_each_possible_cpu(cpu) { > - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, > - cpu); > - int node; > - struct slab *slab; > - > - slab = READ_ONCE(c->slab); > - if (!slab) > - continue; > - > - node = slab_nid(slab); > - if (flags & SO_TOTAL) > - x = slab->objects; > - else if (flags & SO_OBJECTS) > - x = slab->inuse; > - else > - x = 1; > - > - total += x; > - nodes[node] += x; > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - slab = slub_percpu_partial_read_once(c); > - if (slab) { > - node = slab_nid(slab); > - if (flags & SO_TOTAL) > - WARN_ON_ONCE(1); > - else if (flags & SO_OBJECTS) > - WARN_ON_ONCE(1); > - else > - x = slab->slabs; > - total += x; > - nodes[node] += x; > - } > -#endif > - } > - } > - > - /* > - * It is impossible to take "mem_hotplug_lock" here with "kernfs_mutex" > - * already held which will conflict with an existing lock order: > - * > - * mem_hotplug_lock->slab_mutex->kernfs_mutex > - * > - * We don't really need mem_hotplug_lock (to hold off > - * slab_mem_going_offline_callback) here because slab's memory hot > - * unplug code doesn't destroy the kmem_cache->node[] data. > - */ > - > -#ifdef CONFIG_SLUB_DEBUG > - if (flags & SO_ALL) { > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - > - if (flags & SO_TOTAL) > - x = atomic_long_read(&n->total_objects); > - else if (flags & SO_OBJECTS) > - x = atomic_long_read(&n->total_objects) - > - count_partial(n, count_free); > - else > - x = atomic_long_read(&n->nr_slabs); > - total += x; > - nodes[node] += x; > - } > - > - } else > -#endif > - if (flags & SO_PARTIAL) { > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - if (flags & SO_TOTAL) > - x = count_partial(n, count_total); > - else if (flags & SO_OBJECTS) > - x = count_partial(n, count_inuse); > - else > - x = n->nr_partial; > - total += x; > - nodes[node] += x; > - } > - } > - > - len += sysfs_emit_at(buf, len, "%lu", total); > -#ifdef CONFIG_NUMA > - for (node = 0; node < nr_node_ids; node++) { > - if (nodes[node]) > - len += sysfs_emit_at(buf, len, " N%d=%lu", > - node, nodes[node]); > - } > -#endif > - len += sysfs_emit_at(buf, len, "\n"); > - kfree(nodes); > - > - return len; > -} > - > -#define to_slab_attr(n) container_of(n, struct slab_attribute, attr) > -#define to_slab(n) container_of(n, struct kmem_cache, kobj) > - > -struct slab_attribute { > - struct attribute attr; > - ssize_t (*show)(struct kmem_cache *s, char *buf); > - ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count); > -}; > - > -#define SLAB_ATTR_RO(_name) \ > - static struct slab_attribute _name##_attr = __ATTR_RO_MODE(_name, 0400) > - > -#define SLAB_ATTR(_name) \ > - static struct slab_attribute _name##_attr = __ATTR_RW_MODE(_name, 0600) > - > -static ssize_t slab_size_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->size); > -} > -SLAB_ATTR_RO(slab_size); > - > -static ssize_t align_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->align); > -} > -SLAB_ATTR_RO(align); > - > -static ssize_t object_size_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->object_size); > -} > -SLAB_ATTR_RO(object_size); > - > -static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", oo_objects(s->oo)); > -} > -SLAB_ATTR_RO(objs_per_slab); > - > -static ssize_t order_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", oo_order(s->oo)); > -} > -SLAB_ATTR_RO(order); > - > -static ssize_t min_partial_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%lu\n", s->min_partial); > -} > - > -static ssize_t min_partial_store(struct kmem_cache *s, const char *buf, > - size_t length) > -{ > - unsigned long min; > - int err; > - > - err = kstrtoul(buf, 10, &min); > - if (err) > - return err; > - > - s->min_partial = min; > - return length; > -} > -SLAB_ATTR(min_partial); > - > -static ssize_t cpu_partial_show(struct kmem_cache *s, char *buf) > -{ > - unsigned int nr_partial = 0; > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - nr_partial = s->cpu_partial; > -#endif > - > - return sysfs_emit(buf, "%u\n", nr_partial); > -} > - > -static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf, > - size_t length) > -{ > - unsigned int objects; > - int err; > - > - err = kstrtouint(buf, 10, &objects); > - if (err) > - return err; > - if (objects && !kmem_cache_has_cpu_partial(s)) > - return -EINVAL; > - > - slub_set_cpu_partial(s, objects); > - flush_all(s); > - return length; > -} > -SLAB_ATTR(cpu_partial); > - > -static ssize_t ctor_show(struct kmem_cache *s, char *buf) > -{ > - if (!s->ctor) > - return 0; > - return sysfs_emit(buf, "%pS\n", s->ctor); > -} > -SLAB_ATTR_RO(ctor); > - > -static ssize_t aliases_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", s->refcount < 0 ? 0 : s->refcount - 1); > -} > -SLAB_ATTR_RO(aliases); > - > -static ssize_t partial_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_PARTIAL); > -} > -SLAB_ATTR_RO(partial); > - > -static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_CPU); > -} > -SLAB_ATTR_RO(cpu_slabs); > - > -static ssize_t objects_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS); > -} > -SLAB_ATTR_RO(objects); > - > -static ssize_t objects_partial_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS); > -} > -SLAB_ATTR_RO(objects_partial); > - > -static ssize_t slabs_cpu_partial_show(struct kmem_cache *s, char *buf) > -{ > - int objects = 0; > - int slabs = 0; > - int cpu __maybe_unused; > - int len = 0; > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - for_each_online_cpu(cpu) { > - struct slab *slab; > - > - slab = slub_percpu_partial(per_cpu_ptr(s->cpu_slab, cpu)); > - > - if (slab) > - slabs += slab->slabs; > - } > -#endif > - > - /* Approximate half-full slabs, see slub_set_cpu_partial() */ > - objects = (slabs * oo_objects(s->oo)) / 2; > - len += sysfs_emit_at(buf, len, "%d(%d)", objects, slabs); > - > -#if defined(CONFIG_SLUB_CPU_PARTIAL) && defined(CONFIG_SMP) > - for_each_online_cpu(cpu) { > - struct slab *slab; > - > - slab = slub_percpu_partial(per_cpu_ptr(s->cpu_slab, cpu)); > - if (slab) { > - slabs = READ_ONCE(slab->slabs); > - objects = (slabs * oo_objects(s->oo)) / 2; > - len += sysfs_emit_at(buf, len, " C%d=%d(%d)", > - cpu, objects, slabs); > - } > - } > -#endif > - len += sysfs_emit_at(buf, len, "\n"); > - > - return len; > -} > -SLAB_ATTR_RO(slabs_cpu_partial); > - > -static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT)); > -} > -SLAB_ATTR_RO(reclaim_account); > - > -static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN)); > -} > -SLAB_ATTR_RO(hwcache_align); > - > -#ifdef CONFIG_ZONE_DMA > -static ssize_t cache_dma_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA)); > -} > -SLAB_ATTR_RO(cache_dma); > -#endif > - > -#ifdef CONFIG_HARDENED_USERCOPY > -static ssize_t usersize_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->usersize); > -} > -SLAB_ATTR_RO(usersize); > -#endif > - > -static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_TYPESAFE_BY_RCU)); > -} > -SLAB_ATTR_RO(destroy_by_rcu); > - > -#ifdef CONFIG_SLUB_DEBUG > -static ssize_t slabs_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_ALL); > -} > -SLAB_ATTR_RO(slabs); > - > -static ssize_t total_objects_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_ALL|SO_TOTAL); > -} > -SLAB_ATTR_RO(total_objects); > - > -static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_CONSISTENCY_CHECKS)); > -} > -SLAB_ATTR_RO(sanity_checks); > - > -static ssize_t trace_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_TRACE)); > -} > -SLAB_ATTR_RO(trace); > - > -static ssize_t red_zone_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE)); > -} > - > -SLAB_ATTR_RO(red_zone); > - > -static ssize_t poison_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_POISON)); > -} > - > -SLAB_ATTR_RO(poison); > - > -static ssize_t store_user_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_STORE_USER)); > -} > - > -SLAB_ATTR_RO(store_user); > - > -static ssize_t validate_show(struct kmem_cache *s, char *buf) > -{ > - return 0; > -} > - > -static ssize_t validate_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - int ret = -EINVAL; > - > - if (buf[0] == '1' && kmem_cache_debug(s)) { > - ret = validate_slab_cache(s); > - if (ret >= 0) > - ret = length; > - } > - return ret; > -} > -SLAB_ATTR(validate); > - > -#endif /* CONFIG_SLUB_DEBUG */ > - > -#ifdef CONFIG_FAILSLAB > -static ssize_t failslab_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB)); > -} > - > -static ssize_t failslab_store(struct kmem_cache *s, const char *buf, > - size_t length) > -{ > - if (s->refcount > 1) > - return -EINVAL; > - > - if (buf[0] == '1') > - WRITE_ONCE(s->flags, s->flags | SLAB_FAILSLAB); > - else > - WRITE_ONCE(s->flags, s->flags & ~SLAB_FAILSLAB); > - > - return length; > -} > -SLAB_ATTR(failslab); > -#endif > - > -static ssize_t shrink_show(struct kmem_cache *s, char *buf) > -{ > - return 0; > -} > - > -static ssize_t shrink_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - if (buf[0] == '1') > - kmem_cache_shrink(s); > - else > - return -EINVAL; > - return length; > -} > -SLAB_ATTR(shrink); > - > -#ifdef CONFIG_NUMA > -static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->remote_node_defrag_ratio / 10); > -} > - > -static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - unsigned int ratio; > - int err; > - > - err = kstrtouint(buf, 10, &ratio); > - if (err) > - return err; > - if (ratio > 100) > - return -ERANGE; > - > - s->remote_node_defrag_ratio = ratio * 10; > - > - return length; > -} > -SLAB_ATTR(remote_node_defrag_ratio); > -#endif > - > -#ifdef CONFIG_SLUB_STATS > -static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si) > -{ > - unsigned long sum = 0; > - int cpu; > - int len = 0; > - int *data = kmalloc_array(nr_cpu_ids, sizeof(int), GFP_KERNEL); > - > - if (!data) > - return -ENOMEM; > - > - for_each_online_cpu(cpu) { > - unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si]; > - > - data[cpu] = x; > - sum += x; > - } > - > - len += sysfs_emit_at(buf, len, "%lu", sum); > - > -#ifdef CONFIG_SMP > - for_each_online_cpu(cpu) { > - if (data[cpu]) > - len += sysfs_emit_at(buf, len, " C%d=%u", > - cpu, data[cpu]); > - } > -#endif > - kfree(data); > - len += sysfs_emit_at(buf, len, "\n"); > - > - return len; > -} > - > -static void clear_stat(struct kmem_cache *s, enum stat_item si) > -{ > - int cpu; > - > - for_each_online_cpu(cpu) > - per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0; > -} > - > -#define STAT_ATTR(si, text) \ > -static ssize_t text##_show(struct kmem_cache *s, char *buf) \ > -{ \ > - return show_stat(s, buf, si); \ > -} \ > -static ssize_t text##_store(struct kmem_cache *s, \ > - const char *buf, size_t length) \ > -{ \ > - if (buf[0] != '0') \ > - return -EINVAL; \ > - clear_stat(s, si); \ > - return length; \ > -} \ > -SLAB_ATTR(text); \ > - > -STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath); > -STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath); > -STAT_ATTR(FREE_FASTPATH, free_fastpath); > -STAT_ATTR(FREE_SLOWPATH, free_slowpath); > -STAT_ATTR(FREE_FROZEN, free_frozen); > -STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial); > -STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial); > -STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial); > -STAT_ATTR(ALLOC_SLAB, alloc_slab); > -STAT_ATTR(ALLOC_REFILL, alloc_refill); > -STAT_ATTR(ALLOC_NODE_MISMATCH, alloc_node_mismatch); > -STAT_ATTR(FREE_SLAB, free_slab); > -STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush); > -STAT_ATTR(DEACTIVATE_FULL, deactivate_full); > -STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty); > -STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head); > -STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail); > -STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees); > -STAT_ATTR(DEACTIVATE_BYPASS, deactivate_bypass); > -STAT_ATTR(ORDER_FALLBACK, order_fallback); > -STAT_ATTR(CMPXCHG_DOUBLE_CPU_FAIL, cmpxchg_double_cpu_fail); > -STAT_ATTR(CMPXCHG_DOUBLE_FAIL, cmpxchg_double_fail); > -STAT_ATTR(CPU_PARTIAL_ALLOC, cpu_partial_alloc); > -STAT_ATTR(CPU_PARTIAL_FREE, cpu_partial_free); > -STAT_ATTR(CPU_PARTIAL_NODE, cpu_partial_node); > -STAT_ATTR(CPU_PARTIAL_DRAIN, cpu_partial_drain); > -#endif /* CONFIG_SLUB_STATS */ > - > -#ifdef CONFIG_KFENCE > -static ssize_t skip_kfence_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_SKIP_KFENCE)); > -} > - > -static ssize_t skip_kfence_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - int ret = length; > - > - if (buf[0] == '0') > - s->flags &= ~SLAB_SKIP_KFENCE; > - else if (buf[0] == '1') > - s->flags |= SLAB_SKIP_KFENCE; > - else > - ret = -EINVAL; > - > - return ret; > -} > -SLAB_ATTR(skip_kfence); > -#endif > - > -static struct attribute *slab_attrs[] = { > - &slab_size_attr.attr, > - &object_size_attr.attr, > - &objs_per_slab_attr.attr, > - &order_attr.attr, > - &min_partial_attr.attr, > - &cpu_partial_attr.attr, > - &objects_attr.attr, > - &objects_partial_attr.attr, > - &partial_attr.attr, > - &cpu_slabs_attr.attr, > - &ctor_attr.attr, > - &aliases_attr.attr, > - &align_attr.attr, > - &hwcache_align_attr.attr, > - &reclaim_account_attr.attr, > - &destroy_by_rcu_attr.attr, > - &shrink_attr.attr, > - &slabs_cpu_partial_attr.attr, > -#ifdef CONFIG_SLUB_DEBUG > - &total_objects_attr.attr, > - &slabs_attr.attr, > - &sanity_checks_attr.attr, > - &trace_attr.attr, > - &red_zone_attr.attr, > - &poison_attr.attr, > - &store_user_attr.attr, > - &validate_attr.attr, > -#endif > -#ifdef CONFIG_ZONE_DMA > - &cache_dma_attr.attr, > -#endif > -#ifdef CONFIG_NUMA > - &remote_node_defrag_ratio_attr.attr, > -#endif > -#ifdef CONFIG_SLUB_STATS > - &alloc_fastpath_attr.attr, > - &alloc_slowpath_attr.attr, > - &free_fastpath_attr.attr, > - &free_slowpath_attr.attr, > - &free_frozen_attr.attr, > - &free_add_partial_attr.attr, > - &free_remove_partial_attr.attr, > - &alloc_from_partial_attr.attr, > - &alloc_slab_attr.attr, > - &alloc_refill_attr.attr, > - &alloc_node_mismatch_attr.attr, > - &free_slab_attr.attr, > - &cpuslab_flush_attr.attr, > - &deactivate_full_attr.attr, > - &deactivate_empty_attr.attr, > - &deactivate_to_head_attr.attr, > - &deactivate_to_tail_attr.attr, > - &deactivate_remote_frees_attr.attr, > - &deactivate_bypass_attr.attr, > - &order_fallback_attr.attr, > - &cmpxchg_double_fail_attr.attr, > - &cmpxchg_double_cpu_fail_attr.attr, > - &cpu_partial_alloc_attr.attr, > - &cpu_partial_free_attr.attr, > - &cpu_partial_node_attr.attr, > - &cpu_partial_drain_attr.attr, > -#endif > -#ifdef CONFIG_FAILSLAB > - &failslab_attr.attr, > -#endif > -#ifdef CONFIG_HARDENED_USERCOPY > - &usersize_attr.attr, > -#endif > -#ifdef CONFIG_KFENCE > - &skip_kfence_attr.attr, > -#endif > - > - NULL > -}; > - > -static const struct attribute_group slab_attr_group = { > - .attrs = slab_attrs, > -}; > - > -static ssize_t slab_attr_show(struct kobject *kobj, > - struct attribute *attr, > - char *buf) > -{ > - struct slab_attribute *attribute; > - struct kmem_cache *s; > - > - attribute = to_slab_attr(attr); > - s = to_slab(kobj); > - > - if (!attribute->show) > - return -EIO; > - > - return attribute->show(s, buf); > -} > - > -static ssize_t slab_attr_store(struct kobject *kobj, > - struct attribute *attr, > - const char *buf, size_t len) > -{ > - struct slab_attribute *attribute; > - struct kmem_cache *s; > - > - attribute = to_slab_attr(attr); > - s = to_slab(kobj); > - > - if (!attribute->store) > - return -EIO; > - > - return attribute->store(s, buf, len); > -} > - > -static void kmem_cache_release(struct kobject *k) > -{ > - slab_kmem_cache_release(to_slab(k)); > -} > - > -static const struct sysfs_ops slab_sysfs_ops = { > - .show = slab_attr_show, > - .store = slab_attr_store, > -}; > - > -static struct kobj_type slab_ktype = { > - .sysfs_ops = &slab_sysfs_ops, > - .release = kmem_cache_release, > -}; > - > -static struct kset *slab_kset; > - > -static inline struct kset *cache_kset(struct kmem_cache *s) > -{ > - return slab_kset; > -} > - > -#define ID_STR_LENGTH 32 > - > -/* Create a unique string id for a slab cache: > - * > - * Format :[flags-]size > - */ > -static char *create_unique_id(struct kmem_cache *s) > -{ > - char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL); > - char *p = name; > - > - if (!name) > - return ERR_PTR(-ENOMEM); > - > - *p++ = ':'; > - /* > - * First flags affecting slabcache operations. We will only > - * get here for aliasable slabs so we do not need to support > - * too many flags. The flags here must cover all flags that > - * are matched during merging to guarantee that the id is > - * unique. > - */ > - if (s->flags & SLAB_CACHE_DMA) > - *p++ = 'd'; > - if (s->flags & SLAB_CACHE_DMA32) > - *p++ = 'D'; > - if (s->flags & SLAB_RECLAIM_ACCOUNT) > - *p++ = 'a'; > - if (s->flags & SLAB_CONSISTENCY_CHECKS) > - *p++ = 'F'; > - if (s->flags & SLAB_ACCOUNT) > - *p++ = 'A'; > - if (p != name + 1) > - *p++ = '-'; > - p += snprintf(p, ID_STR_LENGTH - (p - name), "%07u", s->size); > - > - if (WARN_ON(p > name + ID_STR_LENGTH - 1)) { > - kfree(name); > - return ERR_PTR(-EINVAL); > - } > - kmsan_unpoison_memory(name, p - name); > - return name; > -} > - > -static int sysfs_slab_add(struct kmem_cache *s) > -{ > - int err; > - const char *name; > - struct kset *kset = cache_kset(s); > - int unmergeable = slab_unmergeable(s); > - > - if (!unmergeable && disable_higher_order_debug && > - (slub_debug & DEBUG_METADATA_FLAGS)) > - unmergeable = 1; > - > - if (unmergeable) { > - /* > - * Slabcache can never be merged so we can use the name proper. > - * This is typically the case for debug situations. In that > - * case we can catch duplicate names easily. > - */ > - sysfs_remove_link(&slab_kset->kobj, s->name); > - name = s->name; > - } else { > - /* > - * Create a unique name for the slab as a target > - * for the symlinks. > - */ > - name = create_unique_id(s); > - if (IS_ERR(name)) > - return PTR_ERR(name); > - } > - > - s->kobj.kset = kset; > - err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, "%s", name); > - if (err) > - goto out; > - > - err = sysfs_create_group(&s->kobj, &slab_attr_group); > - if (err) > - goto out_del_kobj; > - > - if (!unmergeable) { > - /* Setup first alias */ > - sysfs_slab_alias(s, s->name); > - } > -out: > - if (!unmergeable) > - kfree(name); > - return err; > -out_del_kobj: > - kobject_del(&s->kobj); > - goto out; > -} > - > -void sysfs_slab_unlink(struct kmem_cache *s) > -{ > - if (slab_state >= FULL) > - kobject_del(&s->kobj); > -} > - > -void sysfs_slab_release(struct kmem_cache *s) > -{ > - if (slab_state >= FULL) > - kobject_put(&s->kobj); > -} > - > -/* > - * Need to buffer aliases during bootup until sysfs becomes > - * available lest we lose that information. > - */ > -struct saved_alias { > - struct kmem_cache *s; > - const char *name; > - struct saved_alias *next; > -}; > - > -static struct saved_alias *alias_list; > - > -static int sysfs_slab_alias(struct kmem_cache *s, const char *name) > -{ > - struct saved_alias *al; > - > - if (slab_state == FULL) { > - /* > - * If we have a leftover link then remove it. > - */ > - sysfs_remove_link(&slab_kset->kobj, name); > - return sysfs_create_link(&slab_kset->kobj, &s->kobj, name); > - } > - > - al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL); > - if (!al) > - return -ENOMEM; > - > - al->s = s; > - al->name = name; > - al->next = alias_list; > - alias_list = al; > - kmsan_unpoison_memory(al, sizeof(*al)); > - return 0; > -} > - > -static int __init slab_sysfs_init(void) > -{ > - struct kmem_cache *s; > - int err; > - > - mutex_lock(&slab_mutex); > - > - slab_kset = kset_create_and_add("slab", NULL, kernel_kobj); > - if (!slab_kset) { > - mutex_unlock(&slab_mutex); > - pr_err("Cannot register slab subsystem.\n"); > - return -ENOSYS; > - } > - > - slab_state = FULL; > - > - list_for_each_entry(s, &slab_caches, list) { > - err = sysfs_slab_add(s); > - if (err) > - pr_err("SLUB: Unable to add boot slab %s to sysfs\n", > - s->name); > - } > - > - while (alias_list) { > - struct saved_alias *al = alias_list; > - > - alias_list = alias_list->next; > - err = sysfs_slab_alias(al->s, al->name); > - if (err) > - pr_err("SLUB: Unable to add boot slab alias %s to sysfs\n", > - al->name); > - kfree(al); > - } > - > - mutex_unlock(&slab_mutex); > - return 0; > -} > -late_initcall(slab_sysfs_init); > -#endif /* SLAB_SUPPORTS_SYSFS */ > - > -#if defined(CONFIG_SLUB_DEBUG) && defined(CONFIG_DEBUG_FS) > -static int slab_debugfs_show(struct seq_file *seq, void *v) > -{ > - struct loc_track *t = seq->private; > - struct location *l; > - unsigned long idx; > - > - idx = (unsigned long) t->idx; > - if (idx < t->count) { > - l = &t->loc[idx]; > - > - seq_printf(seq, "%7ld ", l->count); > - > - if (l->addr) > - seq_printf(seq, "%pS", (void *)l->addr); > - else > - seq_puts(seq, "<not-available>"); > - > - if (l->waste) > - seq_printf(seq, " waste=%lu/%lu", > - l->count * l->waste, l->waste); > - > - if (l->sum_time != l->min_time) { > - seq_printf(seq, " age=%ld/%llu/%ld", > - l->min_time, div_u64(l->sum_time, l->count), > - l->max_time); > - } else > - seq_printf(seq, " age=%ld", l->min_time); > - > - if (l->min_pid != l->max_pid) > - seq_printf(seq, " pid=%ld-%ld", l->min_pid, l->max_pid); > - else > - seq_printf(seq, " pid=%ld", > - l->min_pid); > - > - if (num_online_cpus() > 1 && !cpumask_empty(to_cpumask(l->cpus))) > - seq_printf(seq, " cpus=%*pbl", > - cpumask_pr_args(to_cpumask(l->cpus))); > - > - if (nr_online_nodes > 1 && !nodes_empty(l->nodes)) > - seq_printf(seq, " nodes=%*pbl", > - nodemask_pr_args(&l->nodes)); > - > -#ifdef CONFIG_STACKDEPOT > - { > - depot_stack_handle_t handle; > - unsigned long *entries; > - unsigned int nr_entries, j; > - > - handle = READ_ONCE(l->handle); > - if (handle) { > - nr_entries = stack_depot_fetch(handle, &entries); > - seq_puts(seq, "\n"); > - for (j = 0; j < nr_entries; j++) > - seq_printf(seq, " %pS\n", (void *)entries[j]); > - } > - } > -#endif > - seq_puts(seq, "\n"); > - } > - > - if (!idx && !t->count) > - seq_puts(seq, "No data\n"); > - > - return 0; > -} > - > -static void slab_debugfs_stop(struct seq_file *seq, void *v) > -{ > -} > - > -static void *slab_debugfs_next(struct seq_file *seq, void *v, loff_t *ppos) > -{ > - struct loc_track *t = seq->private; > - > - t->idx = ++(*ppos); > - if (*ppos <= t->count) > - return ppos; > - > - return NULL; > -} > - > -static int cmp_loc_by_count(const void *a, const void *b, const void *data) > -{ > - struct location *loc1 = (struct location *)a; > - struct location *loc2 = (struct location *)b; > - > - if (loc1->count > loc2->count) > - return -1; > - else > - return 1; > -} > - > -static void *slab_debugfs_start(struct seq_file *seq, loff_t *ppos) > -{ > - struct loc_track *t = seq->private; > - > - t->idx = *ppos; > - return ppos; > -} > - > -static const struct seq_operations slab_debugfs_sops = { > - .start = slab_debugfs_start, > - .next = slab_debugfs_next, > - .stop = slab_debugfs_stop, > - .show = slab_debugfs_show, > -}; > - > -static int slab_debug_trace_open(struct inode *inode, struct file *filep) > -{ > - > - struct kmem_cache_node *n; > - enum track_item alloc; > - int node; > - struct loc_track *t = __seq_open_private(filep, &slab_debugfs_sops, > - sizeof(struct loc_track)); > - struct kmem_cache *s = file_inode(filep)->i_private; > - unsigned long *obj_map; > - > - if (!t) > - return -ENOMEM; > - > - obj_map = bitmap_alloc(oo_objects(s->oo), GFP_KERNEL); > - if (!obj_map) { > - seq_release_private(inode, filep); > - return -ENOMEM; > - } > - > - if (strcmp(filep->f_path.dentry->d_name.name, "alloc_traces") == 0) > - alloc = TRACK_ALLOC; > - else > - alloc = TRACK_FREE; > - > - if (!alloc_loc_track(t, PAGE_SIZE / sizeof(struct location), GFP_KERNEL)) { > - bitmap_free(obj_map); > - seq_release_private(inode, filep); > - return -ENOMEM; > - } > - > - for_each_kmem_cache_node(s, node, n) { > - unsigned long flags; > - struct slab *slab; > - > - if (!atomic_long_read(&n->nr_slabs)) > - continue; > - > - spin_lock_irqsave(&n->list_lock, flags); > - list_for_each_entry(slab, &n->partial, slab_list) > - process_slab(t, s, slab, alloc, obj_map); > - list_for_each_entry(slab, &n->full, slab_list) > - process_slab(t, s, slab, alloc, obj_map); > - spin_unlock_irqrestore(&n->list_lock, flags); > - } > - > - /* Sort locations by count */ > - sort_r(t->loc, t->count, sizeof(struct location), > - cmp_loc_by_count, NULL, NULL); > - > - bitmap_free(obj_map); > - return 0; > -} > - > -static int slab_debug_trace_release(struct inode *inode, struct file *file) > -{ > - struct seq_file *seq = file->private_data; > - struct loc_track *t = seq->private; > - > - free_loc_track(t); > - return seq_release_private(inode, file); > -} > - > -static const struct file_operations slab_debugfs_fops = { > - .open = slab_debug_trace_open, > - .read = seq_read, > - .llseek = seq_lseek, > - .release = slab_debug_trace_release, > -}; > - > -static void debugfs_slab_add(struct kmem_cache *s) > -{ > - struct dentry *slab_cache_dir; > - > - if (unlikely(!slab_debugfs_root)) > - return; > - > - slab_cache_dir = debugfs_create_dir(s->name, slab_debugfs_root); > - > - debugfs_create_file("alloc_traces", 0400, > - slab_cache_dir, s, &slab_debugfs_fops); > - > - debugfs_create_file("free_traces", 0400, > - slab_cache_dir, s, &slab_debugfs_fops); > -} > - > -void debugfs_slab_release(struct kmem_cache *s) > -{ > - debugfs_lookup_and_remove(s->name, slab_debugfs_root); > -} > - > -static int __init slab_debugfs_init(void) > -{ > - struct kmem_cache *s; > - > - slab_debugfs_root = debugfs_create_dir("slab", NULL); > - > - list_for_each_entry(s, &slab_caches, list) > - if (s->flags & SLAB_STORE_USER) > - debugfs_slab_add(s); > - > - return 0; > - > -} > -__initcall(slab_debugfs_init); > -#endif > -/* > - * The /proc/slabinfo ABI > - */ > -#ifdef CONFIG_SLUB_DEBUG > -void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo) > -{ > - unsigned long nr_slabs = 0; > - unsigned long nr_objs = 0; > - unsigned long nr_free = 0; > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - nr_slabs += node_nr_slabs(n); > - nr_objs += node_nr_objs(n); > - nr_free += count_partial(n, count_free); > - } > - > - sinfo->active_objs = nr_objs - nr_free; > - sinfo->num_objs = nr_objs; > - sinfo->active_slabs = nr_slabs; > - sinfo->num_slabs = nr_slabs; > - sinfo->objects_per_slab = oo_objects(s->oo); > - sinfo->cache_order = oo_order(s->oo); > -} > - > -void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s) > -{ > -} > - > -ssize_t slabinfo_write(struct file *file, const char __user *buffer, > - size_t count, loff_t *ppos) > -{ > - return -EIO; > -} > -#endif /* CONFIG_SLUB_DEBUG */ > -- > 2.40.0 > This is such a trivial fixup that it barely even requires review (I imagine Andrew will just take it as-is) but for the sake of being pedantic:- Unnecessarily-Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
On Sat, Apr 1, 2023 at 2:47 AM Vlastimil Babka <vbabka@suse.cz> wrote: > > As the SLOB removal is on track and the SLAB removal is planned, I have > realized - why should we stop there and not remove also SLUB? What's a > slab allocator good for in 2023? The RAM sizes are getting larger and > the modules cheaper [1]. The object constructor trick was perhaps > interesting in 1994, but not with contemporary CPUs. So all the slab > allocator does today is just adding an unnecessary layer of complexity > over the page allocator. > > Thus, with this patch, all three slab allocators are removed, and only a > layer that passes everything to the page allocator remains in the slab.h > and mm/slab_common.c files. This will allow users to gradually > transition away and use the page allocator directly. To summarize the > advantages: > > - Less code to maintain: over 13k lines are removed by this patch, and > more could be removed if I wast^Wspent more time on this, and later as > users are transitioned from the legacy layer. This no longer needs a > separate subsystem so remove it from MAINTAINERS (I hope I can keep the > kernel.org account anyway, though). > > - Simplified MEMCG_KMEM accounting: while I was lazy and just marked it > BROKEN in this patch, it should be trivial to use the page memcg > accounting now that we use the page allocator. The per-object > accounting went through several iterations in the past and was always > complex and added overhead. Page accounting is much simpler by > comparison. > > - Simplified KASAN and friends: also was lazy in this patch so they > can't be enabled but should be easy to fix up and work just on the > page level. > > - Simpler debugging: just use debug_pagealloc=on, no need to look up the > exact syntax of the absurdly complex slub_debug parameter. > > - Speed: didn't measure, but for the page allocator we have pcplists, so > it should scale just fine. No need for the crazy SLUB's cmpxchg_double() > craziness. Maybe that thing could be now removed too? Yeah I can see > just two remaining users. > > Any downsides? Let's look at memory usage after virtme boot: > > Before (with SLUB): > Slab: 26304 kB > > After: > Slab: 295592 kB Good catch. Easy 10x win in memory footprint. Acked-by: Donald Duck <donald@duck.com> > > Well, that's not so bad, see [1]. > > [1] https://www.theregister.com/2023/03/29/dram_prices_crash/ > --- > MAINTAINERS | 15 - > include/linux/slab.h | 211 +- > include/linux/slab_def.h | 124 - > include/linux/slub_def.h | 198 -- > init/Kconfig | 2 +- > mm/Kconfig | 134 +- > mm/Makefile | 10 - > mm/slab.c | 4046 ------------------------ > mm/slab.h | 426 --- > mm/slab_common.c | 876 ++--- > mm/slob.c | 757 ----- > mm/slub.c | 6506 -------------------------------------- > 12 files changed, 228 insertions(+), 13077 deletions(-) > delete mode 100644 include/linux/slab_def.h > delete mode 100644 include/linux/slub_def.h > delete mode 100644 mm/slab.c > delete mode 100644 mm/slob.c > delete mode 100644 mm/slub.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 1dc8bd26b6cf..40b05ad03cd0 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -19183,21 +19183,6 @@ F: drivers/irqchip/irq-sl28cpld.c > F: drivers/pwm/pwm-sl28cpld.c > F: drivers/watchdog/sl28cpld_wdt.c > > -SLAB ALLOCATOR > -M: Christoph Lameter <cl@linux.com> > -M: Pekka Enberg <penberg@kernel.org> > -M: David Rientjes <rientjes@google.com> > -M: Joonsoo Kim <iamjoonsoo.kim@lge.com> > -M: Andrew Morton <akpm@linux-foundation.org> > -M: Vlastimil Babka <vbabka@suse.cz> > -R: Roman Gushchin <roman.gushchin@linux.dev> > -R: Hyeonggon Yoo <42.hyeyoo@gmail.com> > -L: linux-mm@kvack.org > -S: Maintained > -T: git git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab.git > -F: include/linux/sl?b*.h > -F: mm/sl?b* > - > SLCAN CAN NETWORK DRIVER > M: Dario Binacchi <dario.binacchi@amarulasolutions.com> > L: linux-can@vger.kernel.org > diff --git a/include/linux/slab.h b/include/linux/slab.h > index 45af70315a94..61602d54b1d0 100644 > --- a/include/linux/slab.h > +++ b/include/linux/slab.h > @@ -140,13 +140,14 @@ > > /* The following flags affect the page allocator grouping pages by mobility */ > /* Objects are reclaimable */ > -#ifndef CONFIG_SLUB_TINY > #define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U) > -#else > -#define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0) > -#endif > #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */ > > +#define KMALLOC_NOT_NORMAL_BITS \ > + (__GFP_RECLAIMABLE | \ > + (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ > + (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) > + > /* > * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests. > * > @@ -278,38 +279,11 @@ static inline unsigned int arch_slab_minalign(void) > * Kmalloc array related definitions > */ > > -#ifdef CONFIG_SLAB > -/* > - * SLAB and SLUB directly allocates requests fitting in to an order-1 page > - * (PAGE_SIZE*2). Larger requests are passed to the page allocator. > - */ > -#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) > -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > -#ifndef KMALLOC_SHIFT_LOW > -#define KMALLOC_SHIFT_LOW 5 > -#endif > -#endif > - > -#ifdef CONFIG_SLUB > -#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) > -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > -#ifndef KMALLOC_SHIFT_LOW > -#define KMALLOC_SHIFT_LOW 3 > -#endif > -#endif > - > -#ifdef CONFIG_SLOB > -/* > - * SLOB passes all requests larger than one page to the page allocator. > - * No kmalloc array is necessary since objects of different sizes can > - * be allocated from the same page. > - */ > #define KMALLOC_SHIFT_HIGH PAGE_SHIFT > #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > #ifndef KMALLOC_SHIFT_LOW > #define KMALLOC_SHIFT_LOW 3 > #endif > -#endif > > /* Maximum allocatable size */ > #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX) > @@ -336,130 +310,6 @@ static inline unsigned int arch_slab_minalign(void) > #define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \ > (KMALLOC_MIN_SIZE) : 16) > > -/* > - * Whenever changing this, take care of that kmalloc_type() and > - * create_kmalloc_caches() still work as intended. > - * > - * KMALLOC_NORMAL can contain only unaccounted objects whereas KMALLOC_CGROUP > - * is for accounted but unreclaimable and non-dma objects. All the other > - * kmem caches can have both accounted and unaccounted objects. > - */ > -enum kmalloc_cache_type { > - KMALLOC_NORMAL = 0, > -#ifndef CONFIG_ZONE_DMA > - KMALLOC_DMA = KMALLOC_NORMAL, > -#endif > -#ifndef CONFIG_MEMCG_KMEM > - KMALLOC_CGROUP = KMALLOC_NORMAL, > -#endif > -#ifdef CONFIG_SLUB_TINY > - KMALLOC_RECLAIM = KMALLOC_NORMAL, > -#else > - KMALLOC_RECLAIM, > -#endif > -#ifdef CONFIG_ZONE_DMA > - KMALLOC_DMA, > -#endif > -#ifdef CONFIG_MEMCG_KMEM > - KMALLOC_CGROUP, > -#endif > - NR_KMALLOC_TYPES > -}; > - > -#ifndef CONFIG_SLOB > -extern struct kmem_cache * > -kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1]; > - > -/* > - * Define gfp bits that should not be set for KMALLOC_NORMAL. > - */ > -#define KMALLOC_NOT_NORMAL_BITS \ > - (__GFP_RECLAIMABLE | \ > - (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ > - (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) > - > -static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) > -{ > - /* > - * The most common case is KMALLOC_NORMAL, so test for it > - * with a single branch for all the relevant flags. > - */ > - if (likely((flags & KMALLOC_NOT_NORMAL_BITS) == 0)) > - return KMALLOC_NORMAL; > - > - /* > - * At least one of the flags has to be set. Their priorities in > - * decreasing order are: > - * 1) __GFP_DMA > - * 2) __GFP_RECLAIMABLE > - * 3) __GFP_ACCOUNT > - */ > - if (IS_ENABLED(CONFIG_ZONE_DMA) && (flags & __GFP_DMA)) > - return KMALLOC_DMA; > - if (!IS_ENABLED(CONFIG_MEMCG_KMEM) || (flags & __GFP_RECLAIMABLE)) > - return KMALLOC_RECLAIM; > - else > - return KMALLOC_CGROUP; > -} > - > -/* > - * Figure out which kmalloc slab an allocation of a certain size > - * belongs to. > - * 0 = zero alloc > - * 1 = 65 .. 96 bytes > - * 2 = 129 .. 192 bytes > - * n = 2^(n-1)+1 .. 2^n > - * > - * Note: __kmalloc_index() is compile-time optimized, and not runtime optimized; > - * typical usage is via kmalloc_index() and therefore evaluated at compile-time. > - * Callers where !size_is_constant should only be test modules, where runtime > - * overheads of __kmalloc_index() can be tolerated. Also see kmalloc_slab(). > - */ > -static __always_inline unsigned int __kmalloc_index(size_t size, > - bool size_is_constant) > -{ > - if (!size) > - return 0; > - > - if (size <= KMALLOC_MIN_SIZE) > - return KMALLOC_SHIFT_LOW; > - > - if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96) > - return 1; > - if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192) > - return 2; > - if (size <= 8) return 3; > - if (size <= 16) return 4; > - if (size <= 32) return 5; > - if (size <= 64) return 6; > - if (size <= 128) return 7; > - if (size <= 256) return 8; > - if (size <= 512) return 9; > - if (size <= 1024) return 10; > - if (size <= 2 * 1024) return 11; > - if (size <= 4 * 1024) return 12; > - if (size <= 8 * 1024) return 13; > - if (size <= 16 * 1024) return 14; > - if (size <= 32 * 1024) return 15; > - if (size <= 64 * 1024) return 16; > - if (size <= 128 * 1024) return 17; > - if (size <= 256 * 1024) return 18; > - if (size <= 512 * 1024) return 19; > - if (size <= 1024 * 1024) return 20; > - if (size <= 2 * 1024 * 1024) return 21; > - > - if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant) > - BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()"); > - else > - BUG(); > - > - /* Will never be reached. Needed because the compiler may complain */ > - return -1; > -} > -static_assert(PAGE_SHIFT <= 20); > -#define kmalloc_index(s) __kmalloc_index(s, true) > -#endif /* !CONFIG_SLOB */ > - > void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __alloc_size(1); > > /** > @@ -567,57 +417,15 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) __assume_page_align > * Try really hard to succeed the allocation but fail > * eventually. > */ > -#ifndef CONFIG_SLOB > -static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) > -{ > - if (__builtin_constant_p(size) && size) { > - unsigned int index; > - > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large(size, flags); > - > - index = kmalloc_index(size); > - return kmalloc_trace( > - kmalloc_caches[kmalloc_type(flags)][index], > - flags, size); > - } > - return __kmalloc(size, flags); > -} > -#else > static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) > { > - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large(size, flags); > - > - return __kmalloc(size, flags); > + return kmalloc_large(size, flags); > } > -#endif > > -#ifndef CONFIG_SLOB > static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) > { > - if (__builtin_constant_p(size) && size) { > - unsigned int index; > - > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large_node(size, flags, node); > - > - index = kmalloc_index(size); > - return kmalloc_node_trace( > - kmalloc_caches[kmalloc_type(flags)][index], > - flags, node, size); > - } > - return __kmalloc_node(size, flags, node); > + return kmalloc_large_node(size, flags, node); > } > -#else > -static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) > -{ > - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large_node(size, flags, node); > - > - return __kmalloc_node(size, flags, node); > -} > -#endif > > /** > * kmalloc_array - allocate memory for an array. > @@ -785,12 +593,7 @@ size_t kmalloc_size_roundup(size_t size); > > void __init kmem_cache_init_late(void); > > -#if defined(CONFIG_SMP) && defined(CONFIG_SLAB) > -int slab_prepare_cpu(unsigned int cpu); > -int slab_dead_cpu(unsigned int cpu); > -#else > #define slab_prepare_cpu NULL > #define slab_dead_cpu NULL > -#endif > > #endif /* _LINUX_SLAB_H */ > diff --git a/include/linux/slab_def.h b/include/linux/slab_def.h > deleted file mode 100644 > index a61e7d55d0d3..000000000000 > --- a/include/linux/slab_def.h > +++ /dev/null > @@ -1,124 +0,0 @@ > -/* SPDX-License-Identifier: GPL-2.0 */ > -#ifndef _LINUX_SLAB_DEF_H > -#define _LINUX_SLAB_DEF_H > - > -#include <linux/kfence.h> > -#include <linux/reciprocal_div.h> > - > -/* > - * Definitions unique to the original Linux SLAB allocator. > - */ > - > -struct kmem_cache { > - struct array_cache __percpu *cpu_cache; > - > -/* 1) Cache tunables. Protected by slab_mutex */ > - unsigned int batchcount; > - unsigned int limit; > - unsigned int shared; > - > - unsigned int size; > - struct reciprocal_value reciprocal_buffer_size; > -/* 2) touched by every alloc & free from the backend */ > - > - slab_flags_t flags; /* constant flags */ > - unsigned int num; /* # of objs per slab */ > - > -/* 3) cache_grow/shrink */ > - /* order of pgs per slab (2^n) */ > - unsigned int gfporder; > - > - /* force GFP flags, e.g. GFP_DMA */ > - gfp_t allocflags; > - > - size_t colour; /* cache colouring range */ > - unsigned int colour_off; /* colour offset */ > - unsigned int freelist_size; > - > - /* constructor func */ > - void (*ctor)(void *obj); > - > -/* 4) cache creation/removal */ > - const char *name; > - struct list_head list; > - int refcount; > - int object_size; > - int align; > - > -/* 5) statistics */ > -#ifdef CONFIG_DEBUG_SLAB > - unsigned long num_active; > - unsigned long num_allocations; > - unsigned long high_mark; > - unsigned long grown; > - unsigned long reaped; > - unsigned long errors; > - unsigned long max_freeable; > - unsigned long node_allocs; > - unsigned long node_frees; > - unsigned long node_overflow; > - atomic_t allochit; > - atomic_t allocmiss; > - atomic_t freehit; > - atomic_t freemiss; > - > - /* > - * If debugging is enabled, then the allocator can add additional > - * fields and/or padding to every object. 'size' contains the total > - * object size including these internal fields, while 'obj_offset' > - * and 'object_size' contain the offset to the user object and its > - * size. > - */ > - int obj_offset; > -#endif /* CONFIG_DEBUG_SLAB */ > - > -#ifdef CONFIG_KASAN_GENERIC > - struct kasan_cache kasan_info; > -#endif > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > - unsigned int *random_seq; > -#endif > - > -#ifdef CONFIG_HARDENED_USERCOPY > - unsigned int useroffset; /* Usercopy region offset */ > - unsigned int usersize; /* Usercopy region size */ > -#endif > - > - struct kmem_cache_node *node[MAX_NUMNODES]; > -}; > - > -static inline void *nearest_obj(struct kmem_cache *cache, const struct slab *slab, > - void *x) > -{ > - void *object = x - (x - slab->s_mem) % cache->size; > - void *last_object = slab->s_mem + (cache->num - 1) * cache->size; > - > - if (unlikely(object > last_object)) > - return last_object; > - else > - return object; > -} > - > -/* > - * We want to avoid an expensive divide : (offset / cache->size) > - * Using the fact that size is a constant for a particular cache, > - * we can replace (offset / cache->size) by > - * reciprocal_divide(offset, cache->reciprocal_buffer_size) > - */ > -static inline unsigned int obj_to_index(const struct kmem_cache *cache, > - const struct slab *slab, void *obj) > -{ > - u32 offset = (obj - slab->s_mem); > - return reciprocal_divide(offset, cache->reciprocal_buffer_size); > -} > - > -static inline int objs_per_slab(const struct kmem_cache *cache, > - const struct slab *slab) > -{ > - if (is_kfence_address(slab_address(slab))) > - return 1; > - return cache->num; > -} > - > -#endif /* _LINUX_SLAB_DEF_H */ > diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h > deleted file mode 100644 > index f6df03f934e5..000000000000 > --- a/include/linux/slub_def.h > +++ /dev/null > @@ -1,198 +0,0 @@ > -/* SPDX-License-Identifier: GPL-2.0 */ > -#ifndef _LINUX_SLUB_DEF_H > -#define _LINUX_SLUB_DEF_H > - > -/* > - * SLUB : A Slab allocator without object queues. > - * > - * (C) 2007 SGI, Christoph Lameter > - */ > -#include <linux/kfence.h> > -#include <linux/kobject.h> > -#include <linux/reciprocal_div.h> > -#include <linux/local_lock.h> > - > -enum stat_item { > - ALLOC_FASTPATH, /* Allocation from cpu slab */ > - ALLOC_SLOWPATH, /* Allocation by getting a new cpu slab */ > - FREE_FASTPATH, /* Free to cpu slab */ > - FREE_SLOWPATH, /* Freeing not to cpu slab */ > - FREE_FROZEN, /* Freeing to frozen slab */ > - FREE_ADD_PARTIAL, /* Freeing moves slab to partial list */ > - FREE_REMOVE_PARTIAL, /* Freeing removes last object */ > - ALLOC_FROM_PARTIAL, /* Cpu slab acquired from node partial list */ > - ALLOC_SLAB, /* Cpu slab acquired from page allocator */ > - ALLOC_REFILL, /* Refill cpu slab from slab freelist */ > - ALLOC_NODE_MISMATCH, /* Switching cpu slab */ > - FREE_SLAB, /* Slab freed to the page allocator */ > - CPUSLAB_FLUSH, /* Abandoning of the cpu slab */ > - DEACTIVATE_FULL, /* Cpu slab was full when deactivated */ > - DEACTIVATE_EMPTY, /* Cpu slab was empty when deactivated */ > - DEACTIVATE_TO_HEAD, /* Cpu slab was moved to the head of partials */ > - DEACTIVATE_TO_TAIL, /* Cpu slab was moved to the tail of partials */ > - DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */ > - DEACTIVATE_BYPASS, /* Implicit deactivation */ > - ORDER_FALLBACK, /* Number of times fallback was necessary */ > - CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */ > - CMPXCHG_DOUBLE_FAIL, /* Number of times that cmpxchg double did not match */ > - CPU_PARTIAL_ALLOC, /* Used cpu partial on alloc */ > - CPU_PARTIAL_FREE, /* Refill cpu partial on free */ > - CPU_PARTIAL_NODE, /* Refill cpu partial from node partial */ > - CPU_PARTIAL_DRAIN, /* Drain cpu partial to node partial */ > - NR_SLUB_STAT_ITEMS }; > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * When changing the layout, make sure freelist and tid are still compatible > - * with this_cpu_cmpxchg_double() alignment requirements. > - */ > -struct kmem_cache_cpu { > - void **freelist; /* Pointer to next available object */ > - unsigned long tid; /* Globally unique transaction id */ > - struct slab *slab; /* The slab from which we are allocating */ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - struct slab *partial; /* Partially allocated frozen slabs */ > -#endif > - local_lock_t lock; /* Protects the fields above */ > -#ifdef CONFIG_SLUB_STATS > - unsigned stat[NR_SLUB_STAT_ITEMS]; > -#endif > -}; > -#endif /* CONFIG_SLUB_TINY */ > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -#define slub_percpu_partial(c) ((c)->partial) > - > -#define slub_set_percpu_partial(c, p) \ > -({ \ > - slub_percpu_partial(c) = (p)->next; \ > -}) > - > -#define slub_percpu_partial_read_once(c) READ_ONCE(slub_percpu_partial(c)) > -#else > -#define slub_percpu_partial(c) NULL > - > -#define slub_set_percpu_partial(c, p) > - > -#define slub_percpu_partial_read_once(c) NULL > -#endif // CONFIG_SLUB_CPU_PARTIAL > - > -/* > - * Word size structure that can be atomically updated or read and that > - * contains both the order and the number of objects that a slab of the > - * given order would contain. > - */ > -struct kmem_cache_order_objects { > - unsigned int x; > -}; > - > -/* > - * Slab cache management. > - */ > -struct kmem_cache { > -#ifndef CONFIG_SLUB_TINY > - struct kmem_cache_cpu __percpu *cpu_slab; > -#endif > - /* Used for retrieving partial slabs, etc. */ > - slab_flags_t flags; > - unsigned long min_partial; > - unsigned int size; /* The size of an object including metadata */ > - unsigned int object_size;/* The size of an object without metadata */ > - struct reciprocal_value reciprocal_size; > - unsigned int offset; /* Free pointer offset */ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - /* Number of per cpu partial objects to keep around */ > - unsigned int cpu_partial; > - /* Number of per cpu partial slabs to keep around */ > - unsigned int cpu_partial_slabs; > -#endif > - struct kmem_cache_order_objects oo; > - > - /* Allocation and freeing of slabs */ > - struct kmem_cache_order_objects min; > - gfp_t allocflags; /* gfp flags to use on each alloc */ > - int refcount; /* Refcount for slab cache destroy */ > - void (*ctor)(void *); > - unsigned int inuse; /* Offset to metadata */ > - unsigned int align; /* Alignment */ > - unsigned int red_left_pad; /* Left redzone padding size */ > - const char *name; /* Name (only for display!) */ > - struct list_head list; /* List of slab caches */ > -#ifdef CONFIG_SYSFS > - struct kobject kobj; /* For sysfs */ > -#endif > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - unsigned long random; > -#endif > - > -#ifdef CONFIG_NUMA > - /* > - * Defragmentation by allocating from a remote node. > - */ > - unsigned int remote_node_defrag_ratio; > -#endif > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > - unsigned int *random_seq; > -#endif > - > -#ifdef CONFIG_KASAN_GENERIC > - struct kasan_cache kasan_info; > -#endif > - > -#ifdef CONFIG_HARDENED_USERCOPY > - unsigned int useroffset; /* Usercopy region offset */ > - unsigned int usersize; /* Usercopy region size */ > -#endif > - > - struct kmem_cache_node *node[MAX_NUMNODES]; > -}; > - > -#if defined(CONFIG_SYSFS) && !defined(CONFIG_SLUB_TINY) > -#define SLAB_SUPPORTS_SYSFS > -void sysfs_slab_unlink(struct kmem_cache *); > -void sysfs_slab_release(struct kmem_cache *); > -#else > -static inline void sysfs_slab_unlink(struct kmem_cache *s) > -{ > -} > -static inline void sysfs_slab_release(struct kmem_cache *s) > -{ > -} > -#endif > - > -void *fixup_red_left(struct kmem_cache *s, void *p); > - > -static inline void *nearest_obj(struct kmem_cache *cache, const struct slab *slab, > - void *x) { > - void *object = x - (x - slab_address(slab)) % cache->size; > - void *last_object = slab_address(slab) + > - (slab->objects - 1) * cache->size; > - void *result = (unlikely(object > last_object)) ? last_object : object; > - > - result = fixup_red_left(cache, result); > - return result; > -} > - > -/* Determine object index from a given position */ > -static inline unsigned int __obj_to_index(const struct kmem_cache *cache, > - void *addr, void *obj) > -{ > - return reciprocal_divide(kasan_reset_tag(obj) - addr, > - cache->reciprocal_size); > -} > - > -static inline unsigned int obj_to_index(const struct kmem_cache *cache, > - const struct slab *slab, void *obj) > -{ > - if (is_kfence_address(obj)) > - return 0; > - return __obj_to_index(cache, slab_address(slab), obj); > -} > - > -static inline int objs_per_slab(const struct kmem_cache *cache, > - const struct slab *slab) > -{ > - return slab->objects; > -} > -#endif /* _LINUX_SLUB_DEF_H */ > diff --git a/init/Kconfig b/init/Kconfig > index 1fb5f313d18f..45be2eedf75c 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -973,7 +973,7 @@ config MEMCG > > config MEMCG_KMEM > bool > - depends on MEMCG && !SLOB > + depends on MEMCG && BROKEN > default y > > config BLK_CGROUP > diff --git a/mm/Kconfig b/mm/Kconfig > index 4751031f3f05..f07e81bca39e 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -210,134 +210,9 @@ config ZSMALLOC_CHAIN_SIZE > > For more information, see zsmalloc documentation. > > -menu "SLAB allocator options" > - > -choice > - prompt "Choose SLAB allocator" > - default SLUB > - help > - This option allows to select a slab allocator. > - > -config SLAB > - bool "SLAB" > - depends on !PREEMPT_RT > - select HAVE_HARDENED_USERCOPY_ALLOCATOR > - help > - The regular slab allocator that is established and known to work > - well in all environments. It organizes cache hot objects in > - per cpu and per node queues. > - > -config SLUB > - bool "SLUB (Unqueued Allocator)" > - select HAVE_HARDENED_USERCOPY_ALLOCATOR > - help > - SLUB is a slab allocator that minimizes cache line usage > - instead of managing queues of cached objects (SLAB approach). > - Per cpu caching is realized using slabs of objects instead > - of queues of objects. SLUB can use memory efficiently > - and has enhanced diagnostics. SLUB is the default choice for > - a slab allocator. > - > -config SLOB_DEPRECATED > - depends on EXPERT > - bool "SLOB (Simple Allocator - DEPRECATED)" > - depends on !PREEMPT_RT > - help > - Deprecated and scheduled for removal in a few cycles. SLUB > - recommended as replacement. CONFIG_SLUB_TINY can be considered > - on systems with 16MB or less RAM. > - > - If you need SLOB to stay, please contact linux-mm@kvack.org and > - people listed in the SLAB ALLOCATOR section of MAINTAINERS file, > - with your use case. > - > - SLOB replaces the stock allocator with a drastically simpler > - allocator. SLOB is generally more space efficient but > - does not perform as well on large systems. > - > -endchoice > - > -config SLOB > - bool > - default y > - depends on SLOB_DEPRECATED > - > -config SLUB_TINY > - bool "Configure SLUB for minimal memory footprint" > - depends on SLUB && EXPERT > - select SLAB_MERGE_DEFAULT > - help > - Configures the SLUB allocator in a way to achieve minimal memory > - footprint, sacrificing scalability, debugging and other features. > - This is intended only for the smallest system that had used the > - SLOB allocator and is not recommended for systems with more than > - 16MB RAM. > - > - If unsure, say N. > - > -config SLAB_MERGE_DEFAULT > - bool "Allow slab caches to be merged" > - default y > - depends on SLAB || SLUB > - help > - For reduced kernel memory fragmentation, slab caches can be > - merged when they share the same size and other characteristics. > - This carries a risk of kernel heap overflows being able to > - overwrite objects from merged caches (and more easily control > - cache layout), which makes such heap attacks easier to exploit > - by attackers. By keeping caches unmerged, these kinds of exploits > - can usually only damage objects in the same cache. To disable > - merging at runtime, "slab_nomerge" can be passed on the kernel > - command line. > - > -config SLAB_FREELIST_RANDOM > - bool "Randomize slab freelist" > - depends on SLAB || (SLUB && !SLUB_TINY) > - help > - Randomizes the freelist order used on creating new pages. This > - security feature reduces the predictability of the kernel slab > - allocator against heap overflows. > - > -config SLAB_FREELIST_HARDENED > - bool "Harden slab freelist metadata" > - depends on SLAB || (SLUB && !SLUB_TINY) > - help > - Many kernel heap attacks try to target slab cache metadata and > - other infrastructure. This options makes minor performance > - sacrifices to harden the kernel slab allocator against common > - freelist exploit methods. Some slab implementations have more > - sanity-checking than others. This option is most effective with > - CONFIG_SLUB. > - > -config SLUB_STATS > - default n > - bool "Enable SLUB performance statistics" > - depends on SLUB && SYSFS && !SLUB_TINY > - help > - SLUB statistics are useful to debug SLUBs allocation behavior in > - order find ways to optimize the allocator. This should never be > - enabled for production use since keeping statistics slows down > - the allocator by a few percentage points. The slabinfo command > - supports the determination of the most active slabs to figure > - out which slabs are relevant to a particular load. > - Try running: slabinfo -DA > - > -config SLUB_CPU_PARTIAL > - default y > - depends on SLUB && SMP && !SLUB_TINY > - bool "SLUB per cpu partial cache" > - help > - Per cpu partial caches accelerate objects allocation and freeing > - that is local to a processor at the price of more indeterminism > - in the latency of the free. On overflow these caches will be cleared > - which requires the taking of locks that may cause latency spikes. > - Typically one would choose no for a realtime system. > - > -endmenu # SLAB allocator options > - > config SHUFFLE_PAGE_ALLOCATOR > bool "Page allocator randomization" > - default SLAB_FREELIST_RANDOM && ACPI_NUMA > + default ACPI_NUMA > help > Randomization of the page allocator improves the average > utilization of a direct-mapped memory-side-cache. See section > @@ -345,10 +220,9 @@ config SHUFFLE_PAGE_ALLOCATOR > 6.2a specification for an example of how a platform advertises > the presence of a memory-side-cache. There are also incidental > security benefits as it reduces the predictability of page > - allocations to compliment SLAB_FREELIST_RANDOM, but the > - default granularity of shuffling on the "MAX_ORDER - 1" i.e, > - 10th order of pages is selected based on cache utilization > - benefits on x86. > + allocations, but the default granularity of shuffling on the > + "MAX_ORDER - 1" i.e, 10th order of pages is selected based on > + cache utilization benefits on x86. > > While the randomization improves cache utilization it may > negatively impact workloads on platforms without a cache. For > diff --git a/mm/Makefile b/mm/Makefile > index 8e105e5b3e29..18b0bb245fc3 100644 > --- a/mm/Makefile > +++ b/mm/Makefile > @@ -4,16 +4,12 @@ > # > > KASAN_SANITIZE_slab_common.o := n > -KASAN_SANITIZE_slab.o := n > -KASAN_SANITIZE_slub.o := n > KCSAN_SANITIZE_kmemleak.o := n > > # These produce frequent data race reports: most of them are due to races on > # the same word but accesses to different bits of that word. Re-enable KCSAN > # for these when we have more consensus on what to do about them. > KCSAN_SANITIZE_slab_common.o := n > -KCSAN_SANITIZE_slab.o := n > -KCSAN_SANITIZE_slub.o := n > KCSAN_SANITIZE_page_alloc.o := n > # But enable explicit instrumentation for memory barriers. > KCSAN_INSTRUMENT_BARRIERS := y > @@ -22,9 +18,6 @@ KCSAN_INSTRUMENT_BARRIERS := y > # flaky coverage that is not a function of syscall inputs. E.g. slab is out of > # free pages, or a task is migrated between nodes. > KCOV_INSTRUMENT_slab_common.o := n > -KCOV_INSTRUMENT_slob.o := n > -KCOV_INSTRUMENT_slab.o := n > -KCOV_INSTRUMENT_slub.o := n > KCOV_INSTRUMENT_page_alloc.o := n > KCOV_INSTRUMENT_debug-pagealloc.o := n > KCOV_INSTRUMENT_kmemleak.o := n > @@ -81,12 +74,9 @@ obj-$(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP) += hugetlb_vmemmap.o > obj-$(CONFIG_NUMA) += mempolicy.o > obj-$(CONFIG_SPARSEMEM) += sparse.o > obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o > -obj-$(CONFIG_SLOB) += slob.o > obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o > obj-$(CONFIG_KSM) += ksm.o > obj-$(CONFIG_PAGE_POISONING) += page_poison.o > -obj-$(CONFIG_SLAB) += slab.o > -obj-$(CONFIG_SLUB) += slub.o > obj-$(CONFIG_KASAN) += kasan/ > obj-$(CONFIG_KFENCE) += kfence/ > obj-$(CONFIG_KMSAN) += kmsan/ > diff --git a/mm/slab.c b/mm/slab.c > deleted file mode 100644 > index edbe722fb906..000000000000 > --- a/mm/slab.c > +++ /dev/null > @@ -1,4046 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * linux/mm/slab.c > - * Written by Mark Hemment, 1996/97. > - * (markhe@nextd.demon.co.uk) > - * > - * kmem_cache_destroy() + some cleanup - 1999 Andrea Arcangeli > - * > - * Major cleanup, different bufctl logic, per-cpu arrays > - * (c) 2000 Manfred Spraul > - * > - * Cleanup, make the head arrays unconditional, preparation for NUMA > - * (c) 2002 Manfred Spraul > - * > - * An implementation of the Slab Allocator as described in outline in; > - * UNIX Internals: The New Frontiers by Uresh Vahalia > - * Pub: Prentice Hall ISBN 0-13-101908-2 > - * or with a little more detail in; > - * The Slab Allocator: An Object-Caching Kernel Memory Allocator > - * Jeff Bonwick (Sun Microsystems). > - * Presented at: USENIX Summer 1994 Technical Conference > - * > - * The memory is organized in caches, one cache for each object type. > - * (e.g. inode_cache, dentry_cache, buffer_head, vm_area_struct) > - * Each cache consists out of many slabs (they are small (usually one > - * page long) and always contiguous), and each slab contains multiple > - * initialized objects. > - * > - * This means, that your constructor is used only for newly allocated > - * slabs and you must pass objects with the same initializations to > - * kmem_cache_free. > - * > - * Each cache can only support one memory type (GFP_DMA, GFP_HIGHMEM, > - * normal). If you need a special memory type, then must create a new > - * cache for that memory type. > - * > - * In order to reduce fragmentation, the slabs are sorted in 3 groups: > - * full slabs with 0 free objects > - * partial slabs > - * empty slabs with no allocated objects > - * > - * If partial slabs exist, then new allocations come from these slabs, > - * otherwise from empty slabs or new slabs are allocated. > - * > - * kmem_cache_destroy() CAN CRASH if you try to allocate from the cache > - * during kmem_cache_destroy(). The caller must prevent concurrent allocs. > - * > - * Each cache has a short per-cpu head array, most allocs > - * and frees go into that array, and if that array overflows, then 1/2 > - * of the entries in the array are given back into the global cache. > - * The head array is strictly LIFO and should improve the cache hit rates. > - * On SMP, it additionally reduces the spinlock operations. > - * > - * The c_cpuarray may not be read with enabled local interrupts - > - * it's changed with a smp_call_function(). > - * > - * SMP synchronization: > - * constructors and destructors are called without any locking. > - * Several members in struct kmem_cache and struct slab never change, they > - * are accessed without any locking. > - * The per-cpu arrays are never accessed from the wrong cpu, no locking, > - * and local interrupts are disabled so slab code is preempt-safe. > - * The non-constant members are protected with a per-cache irq spinlock. > - * > - * Many thanks to Mark Hemment, who wrote another per-cpu slab patch > - * in 2000 - many ideas in the current implementation are derived from > - * his patch. > - * > - * Further notes from the original documentation: > - * > - * 11 April '97. Started multi-threading - markhe > - * The global cache-chain is protected by the mutex 'slab_mutex'. > - * The sem is only needed when accessing/extending the cache-chain, which > - * can never happen inside an interrupt (kmem_cache_create(), > - * kmem_cache_shrink() and kmem_cache_reap()). > - * > - * At present, each engine can be growing a cache. This should be blocked. > - * > - * 15 March 2005. NUMA slab allocator. > - * Shai Fultheim <shai@scalex86.org>. > - * Shobhit Dayal <shobhit@calsoftinc.com> > - * Alok N Kataria <alokk@calsoftinc.com> > - * Christoph Lameter <christoph@lameter.com> > - * > - * Modified the slab allocator to be node aware on NUMA systems. > - * Each node has its own list of partial, free and full slabs. > - * All object allocations for a node occur from node specific slab lists. > - */ > - > -#include <linux/slab.h> > -#include <linux/mm.h> > -#include <linux/poison.h> > -#include <linux/swap.h> > -#include <linux/cache.h> > -#include <linux/interrupt.h> > -#include <linux/init.h> > -#include <linux/compiler.h> > -#include <linux/cpuset.h> > -#include <linux/proc_fs.h> > -#include <linux/seq_file.h> > -#include <linux/notifier.h> > -#include <linux/kallsyms.h> > -#include <linux/kfence.h> > -#include <linux/cpu.h> > -#include <linux/sysctl.h> > -#include <linux/module.h> > -#include <linux/rcupdate.h> > -#include <linux/string.h> > -#include <linux/uaccess.h> > -#include <linux/nodemask.h> > -#include <linux/kmemleak.h> > -#include <linux/mempolicy.h> > -#include <linux/mutex.h> > -#include <linux/fault-inject.h> > -#include <linux/rtmutex.h> > -#include <linux/reciprocal_div.h> > -#include <linux/debugobjects.h> > -#include <linux/memory.h> > -#include <linux/prefetch.h> > -#include <linux/sched/task_stack.h> > - > -#include <net/sock.h> > - > -#include <asm/cacheflush.h> > -#include <asm/tlbflush.h> > -#include <asm/page.h> > - > -#include <trace/events/kmem.h> > - > -#include "internal.h" > - > -#include "slab.h" > - > -/* > - * DEBUG - 1 for kmem_cache_create() to honour; SLAB_RED_ZONE & SLAB_POISON. > - * 0 for faster, smaller code (especially in the critical paths). > - * > - * STATS - 1 to collect stats for /proc/slabinfo. > - * 0 for faster, smaller code (especially in the critical paths). > - * > - * FORCED_DEBUG - 1 enables SLAB_RED_ZONE and SLAB_POISON (if possible) > - */ > - > -#ifdef CONFIG_DEBUG_SLAB > -#define DEBUG 1 > -#define STATS 1 > -#define FORCED_DEBUG 1 > -#else > -#define DEBUG 0 > -#define STATS 0 > -#define FORCED_DEBUG 0 > -#endif > - > -/* Shouldn't this be in a header file somewhere? */ > -#define BYTES_PER_WORD sizeof(void *) > -#define REDZONE_ALIGN max(BYTES_PER_WORD, __alignof__(unsigned long long)) > - > -#ifndef ARCH_KMALLOC_FLAGS > -#define ARCH_KMALLOC_FLAGS SLAB_HWCACHE_ALIGN > -#endif > - > -#define FREELIST_BYTE_INDEX (((PAGE_SIZE >> BITS_PER_BYTE) \ > - <= SLAB_OBJ_MIN_SIZE) ? 1 : 0) > - > -#if FREELIST_BYTE_INDEX > -typedef unsigned char freelist_idx_t; > -#else > -typedef unsigned short freelist_idx_t; > -#endif > - > -#define SLAB_OBJ_MAX_NUM ((1 << sizeof(freelist_idx_t) * BITS_PER_BYTE) - 1) > - > -/* > - * struct array_cache > - * > - * Purpose: > - * - LIFO ordering, to hand out cache-warm objects from _alloc > - * - reduce the number of linked list operations > - * - reduce spinlock operations > - * > - * The limit is stored in the per-cpu structure to reduce the data cache > - * footprint. > - * > - */ > -struct array_cache { > - unsigned int avail; > - unsigned int limit; > - unsigned int batchcount; > - unsigned int touched; > - void *entry[]; /* > - * Must have this definition in here for the proper > - * alignment of array_cache. Also simplifies accessing > - * the entries. > - */ > -}; > - > -struct alien_cache { > - spinlock_t lock; > - struct array_cache ac; > -}; > - > -/* > - * Need this for bootstrapping a per node allocator. > - */ > -#define NUM_INIT_LISTS (2 * MAX_NUMNODES) > -static struct kmem_cache_node __initdata init_kmem_cache_node[NUM_INIT_LISTS]; > -#define CACHE_CACHE 0 > -#define SIZE_NODE (MAX_NUMNODES) > - > -static int drain_freelist(struct kmem_cache *cache, > - struct kmem_cache_node *n, int tofree); > -static void free_block(struct kmem_cache *cachep, void **objpp, int len, > - int node, struct list_head *list); > -static void slabs_destroy(struct kmem_cache *cachep, struct list_head *list); > -static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp); > -static void cache_reap(struct work_struct *unused); > - > -static inline void fixup_objfreelist_debug(struct kmem_cache *cachep, > - void **list); > -static inline void fixup_slab_list(struct kmem_cache *cachep, > - struct kmem_cache_node *n, struct slab *slab, > - void **list); > - > -#define INDEX_NODE kmalloc_index(sizeof(struct kmem_cache_node)) > - > -static void kmem_cache_node_init(struct kmem_cache_node *parent) > -{ > - INIT_LIST_HEAD(&parent->slabs_full); > - INIT_LIST_HEAD(&parent->slabs_partial); > - INIT_LIST_HEAD(&parent->slabs_free); > - parent->total_slabs = 0; > - parent->free_slabs = 0; > - parent->shared = NULL; > - parent->alien = NULL; > - parent->colour_next = 0; > - raw_spin_lock_init(&parent->list_lock); > - parent->free_objects = 0; > - parent->free_touched = 0; > -} > - > -#define MAKE_LIST(cachep, listp, slab, nodeid) \ > - do { \ > - INIT_LIST_HEAD(listp); \ > - list_splice(&get_node(cachep, nodeid)->slab, listp); \ > - } while (0) > - > -#define MAKE_ALL_LISTS(cachep, ptr, nodeid) \ > - do { \ > - MAKE_LIST((cachep), (&(ptr)->slabs_full), slabs_full, nodeid); \ > - MAKE_LIST((cachep), (&(ptr)->slabs_partial), slabs_partial, nodeid); \ > - MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid); \ > - } while (0) > - > -#define CFLGS_OBJFREELIST_SLAB ((slab_flags_t __force)0x40000000U) > -#define CFLGS_OFF_SLAB ((slab_flags_t __force)0x80000000U) > -#define OBJFREELIST_SLAB(x) ((x)->flags & CFLGS_OBJFREELIST_SLAB) > -#define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB) > - > -#define BATCHREFILL_LIMIT 16 > -/* > - * Optimization question: fewer reaps means less probability for unnecessary > - * cpucache drain/refill cycles. > - * > - * OTOH the cpuarrays can contain lots of objects, > - * which could lock up otherwise freeable slabs. > - */ > -#define REAPTIMEOUT_AC (2*HZ) > -#define REAPTIMEOUT_NODE (4*HZ) > - > -#if STATS > -#define STATS_INC_ACTIVE(x) ((x)->num_active++) > -#define STATS_DEC_ACTIVE(x) ((x)->num_active--) > -#define STATS_INC_ALLOCED(x) ((x)->num_allocations++) > -#define STATS_INC_GROWN(x) ((x)->grown++) > -#define STATS_ADD_REAPED(x, y) ((x)->reaped += (y)) > -#define STATS_SET_HIGH(x) \ > - do { \ > - if ((x)->num_active > (x)->high_mark) \ > - (x)->high_mark = (x)->num_active; \ > - } while (0) > -#define STATS_INC_ERR(x) ((x)->errors++) > -#define STATS_INC_NODEALLOCS(x) ((x)->node_allocs++) > -#define STATS_INC_NODEFREES(x) ((x)->node_frees++) > -#define STATS_INC_ACOVERFLOW(x) ((x)->node_overflow++) > -#define STATS_SET_FREEABLE(x, i) \ > - do { \ > - if ((x)->max_freeable < i) \ > - (x)->max_freeable = i; \ > - } while (0) > -#define STATS_INC_ALLOCHIT(x) atomic_inc(&(x)->allochit) > -#define STATS_INC_ALLOCMISS(x) atomic_inc(&(x)->allocmiss) > -#define STATS_INC_FREEHIT(x) atomic_inc(&(x)->freehit) > -#define STATS_INC_FREEMISS(x) atomic_inc(&(x)->freemiss) > -#else > -#define STATS_INC_ACTIVE(x) do { } while (0) > -#define STATS_DEC_ACTIVE(x) do { } while (0) > -#define STATS_INC_ALLOCED(x) do { } while (0) > -#define STATS_INC_GROWN(x) do { } while (0) > -#define STATS_ADD_REAPED(x, y) do { (void)(y); } while (0) > -#define STATS_SET_HIGH(x) do { } while (0) > -#define STATS_INC_ERR(x) do { } while (0) > -#define STATS_INC_NODEALLOCS(x) do { } while (0) > -#define STATS_INC_NODEFREES(x) do { } while (0) > -#define STATS_INC_ACOVERFLOW(x) do { } while (0) > -#define STATS_SET_FREEABLE(x, i) do { } while (0) > -#define STATS_INC_ALLOCHIT(x) do { } while (0) > -#define STATS_INC_ALLOCMISS(x) do { } while (0) > -#define STATS_INC_FREEHIT(x) do { } while (0) > -#define STATS_INC_FREEMISS(x) do { } while (0) > -#endif > - > -#if DEBUG > - > -/* > - * memory layout of objects: > - * 0 : objp > - * 0 .. cachep->obj_offset - BYTES_PER_WORD - 1: padding. This ensures that > - * the end of an object is aligned with the end of the real > - * allocation. Catches writes behind the end of the allocation. > - * cachep->obj_offset - BYTES_PER_WORD .. cachep->obj_offset - 1: > - * redzone word. > - * cachep->obj_offset: The real object. > - * cachep->size - 2* BYTES_PER_WORD: redzone word [BYTES_PER_WORD long] > - * cachep->size - 1* BYTES_PER_WORD: last caller address > - * [BYTES_PER_WORD long] > - */ > -static int obj_offset(struct kmem_cache *cachep) > -{ > - return cachep->obj_offset; > -} > - > -static unsigned long long *dbg_redzone1(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); > - return (unsigned long long *) (objp + obj_offset(cachep) - > - sizeof(unsigned long long)); > -} > - > -static unsigned long long *dbg_redzone2(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); > - if (cachep->flags & SLAB_STORE_USER) > - return (unsigned long long *)(objp + cachep->size - > - sizeof(unsigned long long) - > - REDZONE_ALIGN); > - return (unsigned long long *) (objp + cachep->size - > - sizeof(unsigned long long)); > -} > - > -static void **dbg_userword(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_STORE_USER)); > - return (void **)(objp + cachep->size - BYTES_PER_WORD); > -} > - > -#else > - > -#define obj_offset(x) 0 > -#define dbg_redzone1(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) > -#define dbg_redzone2(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) > -#define dbg_userword(cachep, objp) ({BUG(); (void **)NULL;}) > - > -#endif > - > -/* > - * Do not go above this order unless 0 objects fit into the slab or > - * overridden on the command line. > - */ > -#define SLAB_MAX_ORDER_HI 1 > -#define SLAB_MAX_ORDER_LO 0 > -static int slab_max_order = SLAB_MAX_ORDER_LO; > -static bool slab_max_order_set __initdata; > - > -static inline void *index_to_obj(struct kmem_cache *cache, > - const struct slab *slab, unsigned int idx) > -{ > - return slab->s_mem + cache->size * idx; > -} > - > -#define BOOT_CPUCACHE_ENTRIES 1 > -/* internal cache of cache description objs */ > -static struct kmem_cache kmem_cache_boot = { > - .batchcount = 1, > - .limit = BOOT_CPUCACHE_ENTRIES, > - .shared = 1, > - .size = sizeof(struct kmem_cache), > - .name = "kmem_cache", > -}; > - > -static DEFINE_PER_CPU(struct delayed_work, slab_reap_work); > - > -static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) > -{ > - return this_cpu_ptr(cachep->cpu_cache); > -} > - > -/* > - * Calculate the number of objects and left-over bytes for a given buffer size. > - */ > -static unsigned int cache_estimate(unsigned long gfporder, size_t buffer_size, > - slab_flags_t flags, size_t *left_over) > -{ > - unsigned int num; > - size_t slab_size = PAGE_SIZE << gfporder; > - > - /* > - * The slab management structure can be either off the slab or > - * on it. For the latter case, the memory allocated for a > - * slab is used for: > - * > - * - @buffer_size bytes for each object > - * - One freelist_idx_t for each object > - * > - * We don't need to consider alignment of freelist because > - * freelist will be at the end of slab page. The objects will be > - * at the correct alignment. > - * > - * If the slab management structure is off the slab, then the > - * alignment will already be calculated into the size. Because > - * the slabs are all pages aligned, the objects will be at the > - * correct alignment when allocated. > - */ > - if (flags & (CFLGS_OBJFREELIST_SLAB | CFLGS_OFF_SLAB)) { > - num = slab_size / buffer_size; > - *left_over = slab_size % buffer_size; > - } else { > - num = slab_size / (buffer_size + sizeof(freelist_idx_t)); > - *left_over = slab_size % > - (buffer_size + sizeof(freelist_idx_t)); > - } > - > - return num; > -} > - > -#if DEBUG > -#define slab_error(cachep, msg) __slab_error(__func__, cachep, msg) > - > -static void __slab_error(const char *function, struct kmem_cache *cachep, > - char *msg) > -{ > - pr_err("slab error in %s(): cache `%s': %s\n", > - function, cachep->name, msg); > - dump_stack(); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > -#endif > - > -/* > - * By default on NUMA we use alien caches to stage the freeing of > - * objects allocated from other nodes. This causes massive memory > - * inefficiencies when using fake NUMA setup to split memory into a > - * large number of small nodes, so it can be disabled on the command > - * line > - */ > - > -static int use_alien_caches __read_mostly = 1; > -static int __init noaliencache_setup(char *s) > -{ > - use_alien_caches = 0; > - return 1; > -} > -__setup("noaliencache", noaliencache_setup); > - > -static int __init slab_max_order_setup(char *str) > -{ > - get_option(&str, &slab_max_order); > - slab_max_order = slab_max_order < 0 ? 0 : > - min(slab_max_order, MAX_ORDER - 1); > - slab_max_order_set = true; > - > - return 1; > -} > -__setup("slab_max_order=", slab_max_order_setup); > - > -#ifdef CONFIG_NUMA > -/* > - * Special reaping functions for NUMA systems called from cache_reap(). > - * These take care of doing round robin flushing of alien caches (containing > - * objects freed on different nodes from which they were allocated) and the > - * flushing of remote pcps by calling drain_node_pages. > - */ > -static DEFINE_PER_CPU(unsigned long, slab_reap_node); > - > -static void init_reap_node(int cpu) > -{ > - per_cpu(slab_reap_node, cpu) = next_node_in(cpu_to_mem(cpu), > - node_online_map); > -} > - > -static void next_reap_node(void) > -{ > - int node = __this_cpu_read(slab_reap_node); > - > - node = next_node_in(node, node_online_map); > - __this_cpu_write(slab_reap_node, node); > -} > - > -#else > -#define init_reap_node(cpu) do { } while (0) > -#define next_reap_node(void) do { } while (0) > -#endif > - > -/* > - * Initiate the reap timer running on the target CPU. We run at around 1 to 2Hz > - * via the workqueue/eventd. > - * Add the CPU number into the expiration time to minimize the possibility of > - * the CPUs getting into lockstep and contending for the global cache chain > - * lock. > - */ > -static void start_cpu_timer(int cpu) > -{ > - struct delayed_work *reap_work = &per_cpu(slab_reap_work, cpu); > - > - if (reap_work->work.func == NULL) { > - init_reap_node(cpu); > - INIT_DEFERRABLE_WORK(reap_work, cache_reap); > - schedule_delayed_work_on(cpu, reap_work, > - __round_jiffies_relative(HZ, cpu)); > - } > -} > - > -static void init_arraycache(struct array_cache *ac, int limit, int batch) > -{ > - if (ac) { > - ac->avail = 0; > - ac->limit = limit; > - ac->batchcount = batch; > - ac->touched = 0; > - } > -} > - > -static struct array_cache *alloc_arraycache(int node, int entries, > - int batchcount, gfp_t gfp) > -{ > - size_t memsize = sizeof(void *) * entries + sizeof(struct array_cache); > - struct array_cache *ac = NULL; > - > - ac = kmalloc_node(memsize, gfp, node); > - /* > - * The array_cache structures contain pointers to free object. > - * However, when such objects are allocated or transferred to another > - * cache the pointers are not cleared and they could be counted as > - * valid references during a kmemleak scan. Therefore, kmemleak must > - * not scan such objects. > - */ > - kmemleak_no_scan(ac); > - init_arraycache(ac, entries, batchcount); > - return ac; > -} > - > -static noinline void cache_free_pfmemalloc(struct kmem_cache *cachep, > - struct slab *slab, void *objp) > -{ > - struct kmem_cache_node *n; > - int slab_node; > - LIST_HEAD(list); > - > - slab_node = slab_nid(slab); > - n = get_node(cachep, slab_node); > - > - raw_spin_lock(&n->list_lock); > - free_block(cachep, &objp, 1, slab_node, &list); > - raw_spin_unlock(&n->list_lock); > - > - slabs_destroy(cachep, &list); > -} > - > -/* > - * Transfer objects in one arraycache to another. > - * Locking must be handled by the caller. > - * > - * Return the number of entries transferred. > - */ > -static int transfer_objects(struct array_cache *to, > - struct array_cache *from, unsigned int max) > -{ > - /* Figure out how many entries to transfer */ > - int nr = min3(from->avail, max, to->limit - to->avail); > - > - if (!nr) > - return 0; > - > - memcpy(to->entry + to->avail, from->entry + from->avail - nr, > - sizeof(void *) *nr); > - > - from->avail -= nr; > - to->avail += nr; > - return nr; > -} > - > -/* &alien->lock must be held by alien callers. */ > -static __always_inline void __free_one(struct array_cache *ac, void *objp) > -{ > - /* Avoid trivial double-free. */ > - if (IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && > - WARN_ON_ONCE(ac->avail > 0 && ac->entry[ac->avail - 1] == objp)) > - return; > - ac->entry[ac->avail++] = objp; > -} > - > -#ifndef CONFIG_NUMA > - > -#define drain_alien_cache(cachep, alien) do { } while (0) > -#define reap_alien(cachep, n) do { } while (0) > - > -static inline struct alien_cache **alloc_alien_cache(int node, > - int limit, gfp_t gfp) > -{ > - return NULL; > -} > - > -static inline void free_alien_cache(struct alien_cache **ac_ptr) > -{ > -} > - > -static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) > -{ > - return 0; > -} > - > -static inline gfp_t gfp_exact_node(gfp_t flags) > -{ > - return flags & ~__GFP_NOFAIL; > -} > - > -#else /* CONFIG_NUMA */ > - > -static struct alien_cache *__alloc_alien_cache(int node, int entries, > - int batch, gfp_t gfp) > -{ > - size_t memsize = sizeof(void *) * entries + sizeof(struct alien_cache); > - struct alien_cache *alc = NULL; > - > - alc = kmalloc_node(memsize, gfp, node); > - if (alc) { > - kmemleak_no_scan(alc); > - init_arraycache(&alc->ac, entries, batch); > - spin_lock_init(&alc->lock); > - } > - return alc; > -} > - > -static struct alien_cache **alloc_alien_cache(int node, int limit, gfp_t gfp) > -{ > - struct alien_cache **alc_ptr; > - int i; > - > - if (limit > 1) > - limit = 12; > - alc_ptr = kcalloc_node(nr_node_ids, sizeof(void *), gfp, node); > - if (!alc_ptr) > - return NULL; > - > - for_each_node(i) { > - if (i == node || !node_online(i)) > - continue; > - alc_ptr[i] = __alloc_alien_cache(node, limit, 0xbaadf00d, gfp); > - if (!alc_ptr[i]) { > - for (i--; i >= 0; i--) > - kfree(alc_ptr[i]); > - kfree(alc_ptr); > - return NULL; > - } > - } > - return alc_ptr; > -} > - > -static void free_alien_cache(struct alien_cache **alc_ptr) > -{ > - int i; > - > - if (!alc_ptr) > - return; > - for_each_node(i) > - kfree(alc_ptr[i]); > - kfree(alc_ptr); > -} > - > -static void __drain_alien_cache(struct kmem_cache *cachep, > - struct array_cache *ac, int node, > - struct list_head *list) > -{ > - struct kmem_cache_node *n = get_node(cachep, node); > - > - if (ac->avail) { > - raw_spin_lock(&n->list_lock); > - /* > - * Stuff objects into the remote nodes shared array first. > - * That way we could avoid the overhead of putting the objects > - * into the free lists and getting them back later. > - */ > - if (n->shared) > - transfer_objects(n->shared, ac, ac->limit); > - > - free_block(cachep, ac->entry, ac->avail, node, list); > - ac->avail = 0; > - raw_spin_unlock(&n->list_lock); > - } > -} > - > -/* > - * Called from cache_reap() to regularly drain alien caches round robin. > - */ > -static void reap_alien(struct kmem_cache *cachep, struct kmem_cache_node *n) > -{ > - int node = __this_cpu_read(slab_reap_node); > - > - if (n->alien) { > - struct alien_cache *alc = n->alien[node]; > - struct array_cache *ac; > - > - if (alc) { > - ac = &alc->ac; > - if (ac->avail && spin_trylock_irq(&alc->lock)) { > - LIST_HEAD(list); > - > - __drain_alien_cache(cachep, ac, node, &list); > - spin_unlock_irq(&alc->lock); > - slabs_destroy(cachep, &list); > - } > - } > - } > -} > - > -static void drain_alien_cache(struct kmem_cache *cachep, > - struct alien_cache **alien) > -{ > - int i = 0; > - struct alien_cache *alc; > - struct array_cache *ac; > - unsigned long flags; > - > - for_each_online_node(i) { > - alc = alien[i]; > - if (alc) { > - LIST_HEAD(list); > - > - ac = &alc->ac; > - spin_lock_irqsave(&alc->lock, flags); > - __drain_alien_cache(cachep, ac, i, &list); > - spin_unlock_irqrestore(&alc->lock, flags); > - slabs_destroy(cachep, &list); > - } > - } > -} > - > -static int __cache_free_alien(struct kmem_cache *cachep, void *objp, > - int node, int slab_node) > -{ > - struct kmem_cache_node *n; > - struct alien_cache *alien = NULL; > - struct array_cache *ac; > - LIST_HEAD(list); > - > - n = get_node(cachep, node); > - STATS_INC_NODEFREES(cachep); > - if (n->alien && n->alien[slab_node]) { > - alien = n->alien[slab_node]; > - ac = &alien->ac; > - spin_lock(&alien->lock); > - if (unlikely(ac->avail == ac->limit)) { > - STATS_INC_ACOVERFLOW(cachep); > - __drain_alien_cache(cachep, ac, slab_node, &list); > - } > - __free_one(ac, objp); > - spin_unlock(&alien->lock); > - slabs_destroy(cachep, &list); > - } else { > - n = get_node(cachep, slab_node); > - raw_spin_lock(&n->list_lock); > - free_block(cachep, &objp, 1, slab_node, &list); > - raw_spin_unlock(&n->list_lock); > - slabs_destroy(cachep, &list); > - } > - return 1; > -} > - > -static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) > -{ > - int slab_node = slab_nid(virt_to_slab(objp)); > - int node = numa_mem_id(); > - /* > - * Make sure we are not freeing an object from another node to the array > - * cache on this cpu. > - */ > - if (likely(node == slab_node)) > - return 0; > - > - return __cache_free_alien(cachep, objp, node, slab_node); > -} > - > -/* > - * Construct gfp mask to allocate from a specific node but do not reclaim or > - * warn about failures. > - */ > -static inline gfp_t gfp_exact_node(gfp_t flags) > -{ > - return (flags | __GFP_THISNODE | __GFP_NOWARN) & ~(__GFP_RECLAIM|__GFP_NOFAIL); > -} > -#endif > - > -static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp) > -{ > - struct kmem_cache_node *n; > - > - /* > - * Set up the kmem_cache_node for cpu before we can > - * begin anything. Make sure some other cpu on this > - * node has not already allocated this > - */ > - n = get_node(cachep, node); > - if (n) { > - raw_spin_lock_irq(&n->list_lock); > - n->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount + > - cachep->num; > - raw_spin_unlock_irq(&n->list_lock); > - > - return 0; > - } > - > - n = kmalloc_node(sizeof(struct kmem_cache_node), gfp, node); > - if (!n) > - return -ENOMEM; > - > - kmem_cache_node_init(n); > - n->next_reap = jiffies + REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - > - n->free_limit = > - (1 + nr_cpus_node(node)) * cachep->batchcount + cachep->num; > - > - /* > - * The kmem_cache_nodes don't come and go as CPUs > - * come and go. slab_mutex provides sufficient > - * protection here. > - */ > - cachep->node[node] = n; > - > - return 0; > -} > - > -#if defined(CONFIG_NUMA) || defined(CONFIG_SMP) > -/* > - * Allocates and initializes node for a node on each slab cache, used for > - * either memory or cpu hotplug. If memory is being hot-added, the kmem_cache_node > - * will be allocated off-node since memory is not yet online for the new node. > - * When hotplugging memory or a cpu, existing nodes are not replaced if > - * already in use. > - * > - * Must hold slab_mutex. > - */ > -static int init_cache_node_node(int node) > -{ > - int ret; > - struct kmem_cache *cachep; > - > - list_for_each_entry(cachep, &slab_caches, list) { > - ret = init_cache_node(cachep, node, GFP_KERNEL); > - if (ret) > - return ret; > - } > - > - return 0; > -} > -#endif > - > -static int setup_kmem_cache_node(struct kmem_cache *cachep, > - int node, gfp_t gfp, bool force_change) > -{ > - int ret = -ENOMEM; > - struct kmem_cache_node *n; > - struct array_cache *old_shared = NULL; > - struct array_cache *new_shared = NULL; > - struct alien_cache **new_alien = NULL; > - LIST_HEAD(list); > - > - if (use_alien_caches) { > - new_alien = alloc_alien_cache(node, cachep->limit, gfp); > - if (!new_alien) > - goto fail; > - } > - > - if (cachep->shared) { > - new_shared = alloc_arraycache(node, > - cachep->shared * cachep->batchcount, 0xbaadf00d, gfp); > - if (!new_shared) > - goto fail; > - } > - > - ret = init_cache_node(cachep, node, gfp); > - if (ret) > - goto fail; > - > - n = get_node(cachep, node); > - raw_spin_lock_irq(&n->list_lock); > - if (n->shared && force_change) { > - free_block(cachep, n->shared->entry, > - n->shared->avail, node, &list); > - n->shared->avail = 0; > - } > - > - if (!n->shared || force_change) { > - old_shared = n->shared; > - n->shared = new_shared; > - new_shared = NULL; > - } > - > - if (!n->alien) { > - n->alien = new_alien; > - new_alien = NULL; > - } > - > - raw_spin_unlock_irq(&n->list_lock); > - slabs_destroy(cachep, &list); > - > - /* > - * To protect lockless access to n->shared during irq disabled context. > - * If n->shared isn't NULL in irq disabled context, accessing to it is > - * guaranteed to be valid until irq is re-enabled, because it will be > - * freed after synchronize_rcu(). > - */ > - if (old_shared && force_change) > - synchronize_rcu(); > - > -fail: > - kfree(old_shared); > - kfree(new_shared); > - free_alien_cache(new_alien); > - > - return ret; > -} > - > -#ifdef CONFIG_SMP > - > -static void cpuup_canceled(long cpu) > -{ > - struct kmem_cache *cachep; > - struct kmem_cache_node *n = NULL; > - int node = cpu_to_mem(cpu); > - const struct cpumask *mask = cpumask_of_node(node); > - > - list_for_each_entry(cachep, &slab_caches, list) { > - struct array_cache *nc; > - struct array_cache *shared; > - struct alien_cache **alien; > - LIST_HEAD(list); > - > - n = get_node(cachep, node); > - if (!n) > - continue; > - > - raw_spin_lock_irq(&n->list_lock); > - > - /* Free limit for this kmem_cache_node */ > - n->free_limit -= cachep->batchcount; > - > - /* cpu is dead; no one can alloc from it. */ > - nc = per_cpu_ptr(cachep->cpu_cache, cpu); > - free_block(cachep, nc->entry, nc->avail, node, &list); > - nc->avail = 0; > - > - if (!cpumask_empty(mask)) { > - raw_spin_unlock_irq(&n->list_lock); > - goto free_slab; > - } > - > - shared = n->shared; > - if (shared) { > - free_block(cachep, shared->entry, > - shared->avail, node, &list); > - n->shared = NULL; > - } > - > - alien = n->alien; > - n->alien = NULL; > - > - raw_spin_unlock_irq(&n->list_lock); > - > - kfree(shared); > - if (alien) { > - drain_alien_cache(cachep, alien); > - free_alien_cache(alien); > - } > - > -free_slab: > - slabs_destroy(cachep, &list); > - } > - /* > - * In the previous loop, all the objects were freed to > - * the respective cache's slabs, now we can go ahead and > - * shrink each nodelist to its limit. > - */ > - list_for_each_entry(cachep, &slab_caches, list) { > - n = get_node(cachep, node); > - if (!n) > - continue; > - drain_freelist(cachep, n, INT_MAX); > - } > -} > - > -static int cpuup_prepare(long cpu) > -{ > - struct kmem_cache *cachep; > - int node = cpu_to_mem(cpu); > - int err; > - > - /* > - * We need to do this right in the beginning since > - * alloc_arraycache's are going to use this list. > - * kmalloc_node allows us to add the slab to the right > - * kmem_cache_node and not this cpu's kmem_cache_node > - */ > - err = init_cache_node_node(node); > - if (err < 0) > - goto bad; > - > - /* > - * Now we can go ahead with allocating the shared arrays and > - * array caches > - */ > - list_for_each_entry(cachep, &slab_caches, list) { > - err = setup_kmem_cache_node(cachep, node, GFP_KERNEL, false); > - if (err) > - goto bad; > - } > - > - return 0; > -bad: > - cpuup_canceled(cpu); > - return -ENOMEM; > -} > - > -int slab_prepare_cpu(unsigned int cpu) > -{ > - int err; > - > - mutex_lock(&slab_mutex); > - err = cpuup_prepare(cpu); > - mutex_unlock(&slab_mutex); > - return err; > -} > - > -/* > - * This is called for a failed online attempt and for a successful > - * offline. > - * > - * Even if all the cpus of a node are down, we don't free the > - * kmem_cache_node of any cache. This is to avoid a race between cpu_down, and > - * a kmalloc allocation from another cpu for memory from the node of > - * the cpu going down. The kmem_cache_node structure is usually allocated from > - * kmem_cache_create() and gets destroyed at kmem_cache_destroy(). > - */ > -int slab_dead_cpu(unsigned int cpu) > -{ > - mutex_lock(&slab_mutex); > - cpuup_canceled(cpu); > - mutex_unlock(&slab_mutex); > - return 0; > -} > -#endif > - > -static int slab_online_cpu(unsigned int cpu) > -{ > - start_cpu_timer(cpu); > - return 0; > -} > - > -static int slab_offline_cpu(unsigned int cpu) > -{ > - /* > - * Shutdown cache reaper. Note that the slab_mutex is held so > - * that if cache_reap() is invoked it cannot do anything > - * expensive but will only modify reap_work and reschedule the > - * timer. > - */ > - cancel_delayed_work_sync(&per_cpu(slab_reap_work, cpu)); > - /* Now the cache_reaper is guaranteed to be not running. */ > - per_cpu(slab_reap_work, cpu).work.func = NULL; > - return 0; > -} > - > -#if defined(CONFIG_NUMA) > -/* > - * Drains freelist for a node on each slab cache, used for memory hot-remove. > - * Returns -EBUSY if all objects cannot be drained so that the node is not > - * removed. > - * > - * Must hold slab_mutex. > - */ > -static int __meminit drain_cache_node_node(int node) > -{ > - struct kmem_cache *cachep; > - int ret = 0; > - > - list_for_each_entry(cachep, &slab_caches, list) { > - struct kmem_cache_node *n; > - > - n = get_node(cachep, node); > - if (!n) > - continue; > - > - drain_freelist(cachep, n, INT_MAX); > - > - if (!list_empty(&n->slabs_full) || > - !list_empty(&n->slabs_partial)) { > - ret = -EBUSY; > - break; > - } > - } > - return ret; > -} > - > -static int __meminit slab_memory_callback(struct notifier_block *self, > - unsigned long action, void *arg) > -{ > - struct memory_notify *mnb = arg; > - int ret = 0; > - int nid; > - > - nid = mnb->status_change_nid; > - if (nid < 0) > - goto out; > - > - switch (action) { > - case MEM_GOING_ONLINE: > - mutex_lock(&slab_mutex); > - ret = init_cache_node_node(nid); > - mutex_unlock(&slab_mutex); > - break; > - case MEM_GOING_OFFLINE: > - mutex_lock(&slab_mutex); > - ret = drain_cache_node_node(nid); > - mutex_unlock(&slab_mutex); > - break; > - case MEM_ONLINE: > - case MEM_OFFLINE: > - case MEM_CANCEL_ONLINE: > - case MEM_CANCEL_OFFLINE: > - break; > - } > -out: > - return notifier_from_errno(ret); > -} > -#endif /* CONFIG_NUMA */ > - > -/* > - * swap the static kmem_cache_node with kmalloced memory > - */ > -static void __init init_list(struct kmem_cache *cachep, struct kmem_cache_node *list, > - int nodeid) > -{ > - struct kmem_cache_node *ptr; > - > - ptr = kmalloc_node(sizeof(struct kmem_cache_node), GFP_NOWAIT, nodeid); > - BUG_ON(!ptr); > - > - memcpy(ptr, list, sizeof(struct kmem_cache_node)); > - /* > - * Do not assume that spinlocks can be initialized via memcpy: > - */ > - raw_spin_lock_init(&ptr->list_lock); > - > - MAKE_ALL_LISTS(cachep, ptr, nodeid); > - cachep->node[nodeid] = ptr; > -} > - > -/* > - * For setting up all the kmem_cache_node for cache whose buffer_size is same as > - * size of kmem_cache_node. > - */ > -static void __init set_up_node(struct kmem_cache *cachep, int index) > -{ > - int node; > - > - for_each_online_node(node) { > - cachep->node[node] = &init_kmem_cache_node[index + node]; > - cachep->node[node]->next_reap = jiffies + > - REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - } > -} > - > -/* > - * Initialisation. Called after the page allocator have been initialised and > - * before smp_init(). > - */ > -void __init kmem_cache_init(void) > -{ > - int i; > - > - kmem_cache = &kmem_cache_boot; > - > - if (!IS_ENABLED(CONFIG_NUMA) || num_possible_nodes() == 1) > - use_alien_caches = 0; > - > - for (i = 0; i < NUM_INIT_LISTS; i++) > - kmem_cache_node_init(&init_kmem_cache_node[i]); > - > - /* > - * Fragmentation resistance on low memory - only use bigger > - * page orders on machines with more than 32MB of memory if > - * not overridden on the command line. > - */ > - if (!slab_max_order_set && totalram_pages() > (32 << 20) >> PAGE_SHIFT) > - slab_max_order = SLAB_MAX_ORDER_HI; > - > - /* Bootstrap is tricky, because several objects are allocated > - * from caches that do not exist yet: > - * 1) initialize the kmem_cache cache: it contains the struct > - * kmem_cache structures of all caches, except kmem_cache itself: > - * kmem_cache is statically allocated. > - * Initially an __init data area is used for the head array and the > - * kmem_cache_node structures, it's replaced with a kmalloc allocated > - * array at the end of the bootstrap. > - * 2) Create the first kmalloc cache. > - * The struct kmem_cache for the new cache is allocated normally. > - * An __init data area is used for the head array. > - * 3) Create the remaining kmalloc caches, with minimally sized > - * head arrays. > - * 4) Replace the __init data head arrays for kmem_cache and the first > - * kmalloc cache with kmalloc allocated arrays. > - * 5) Replace the __init data for kmem_cache_node for kmem_cache and > - * the other cache's with kmalloc allocated memory. > - * 6) Resize the head arrays of the kmalloc caches to their final sizes. > - */ > - > - /* 1) create the kmem_cache */ > - > - /* > - * struct kmem_cache size depends on nr_node_ids & nr_cpu_ids > - */ > - create_boot_cache(kmem_cache, "kmem_cache", > - offsetof(struct kmem_cache, node) + > - nr_node_ids * sizeof(struct kmem_cache_node *), > - SLAB_HWCACHE_ALIGN, 0, 0); > - list_add(&kmem_cache->list, &slab_caches); > - slab_state = PARTIAL; > - > - /* > - * Initialize the caches that provide memory for the kmem_cache_node > - * structures first. Without this, further allocations will bug. > - */ > - kmalloc_caches[KMALLOC_NORMAL][INDEX_NODE] = create_kmalloc_cache( > - kmalloc_info[INDEX_NODE].name[KMALLOC_NORMAL], > - kmalloc_info[INDEX_NODE].size, > - ARCH_KMALLOC_FLAGS, 0, > - kmalloc_info[INDEX_NODE].size); > - slab_state = PARTIAL_NODE; > - setup_kmalloc_cache_index_table(); > - > - /* 5) Replace the bootstrap kmem_cache_node */ > - { > - int nid; > - > - for_each_online_node(nid) { > - init_list(kmem_cache, &init_kmem_cache_node[CACHE_CACHE + nid], nid); > - > - init_list(kmalloc_caches[KMALLOC_NORMAL][INDEX_NODE], > - &init_kmem_cache_node[SIZE_NODE + nid], nid); > - } > - } > - > - create_kmalloc_caches(ARCH_KMALLOC_FLAGS); > -} > - > -void __init kmem_cache_init_late(void) > -{ > - struct kmem_cache *cachep; > - > - /* 6) resize the head arrays to their final sizes */ > - mutex_lock(&slab_mutex); > - list_for_each_entry(cachep, &slab_caches, list) > - if (enable_cpucache(cachep, GFP_NOWAIT)) > - BUG(); > - mutex_unlock(&slab_mutex); > - > - /* Done! */ > - slab_state = FULL; > - > -#ifdef CONFIG_NUMA > - /* > - * Register a memory hotplug callback that initializes and frees > - * node. > - */ > - hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI); > -#endif > - > - /* > - * The reap timers are started later, with a module init call: That part > - * of the kernel is not yet operational. > - */ > -} > - > -static int __init cpucache_init(void) > -{ > - int ret; > - > - /* > - * Register the timers that return unneeded pages to the page allocator > - */ > - ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "SLAB online", > - slab_online_cpu, slab_offline_cpu); > - WARN_ON(ret < 0); > - > - return 0; > -} > -__initcall(cpucache_init); > - > -static noinline void > -slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid) > -{ > -#if DEBUG > - struct kmem_cache_node *n; > - unsigned long flags; > - int node; > - static DEFINE_RATELIMIT_STATE(slab_oom_rs, DEFAULT_RATELIMIT_INTERVAL, > - DEFAULT_RATELIMIT_BURST); > - > - if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slab_oom_rs)) > - return; > - > - pr_warn("SLAB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", > - nodeid, gfpflags, &gfpflags); > - pr_warn(" cache: %s, object size: %d, order: %d\n", > - cachep->name, cachep->size, cachep->gfporder); > - > - for_each_kmem_cache_node(cachep, node, n) { > - unsigned long total_slabs, free_slabs, free_objs; > - > - raw_spin_lock_irqsave(&n->list_lock, flags); > - total_slabs = n->total_slabs; > - free_slabs = n->free_slabs; > - free_objs = n->free_objects; > - raw_spin_unlock_irqrestore(&n->list_lock, flags); > - > - pr_warn(" node %d: slabs: %ld/%ld, objs: %ld/%ld\n", > - node, total_slabs - free_slabs, total_slabs, > - (total_slabs * cachep->num) - free_objs, > - total_slabs * cachep->num); > - } > -#endif > -} > - > -/* > - * Interface to system's page allocator. No need to hold the > - * kmem_cache_node ->list_lock. > - * > - * If we requested dmaable memory, we will get it. Even if we > - * did not request dmaable memory, we might get it, but that > - * would be relatively rare and ignorable. > - */ > -static struct slab *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, > - int nodeid) > -{ > - struct folio *folio; > - struct slab *slab; > - > - flags |= cachep->allocflags; > - > - folio = (struct folio *) __alloc_pages_node(nodeid, flags, cachep->gfporder); > - if (!folio) { > - slab_out_of_memory(cachep, flags, nodeid); > - return NULL; > - } > - > - slab = folio_slab(folio); > - > - account_slab(slab, cachep->gfporder, cachep, flags); > - __folio_set_slab(folio); > - /* Make the flag visible before any changes to folio->mapping */ > - smp_wmb(); > - /* Record if ALLOC_NO_WATERMARKS was set when allocating the slab */ > - if (sk_memalloc_socks() && folio_is_pfmemalloc(folio)) > - slab_set_pfmemalloc(slab); > - > - return slab; > -} > - > -/* > - * Interface to system's page release. > - */ > -static void kmem_freepages(struct kmem_cache *cachep, struct slab *slab) > -{ > - int order = cachep->gfporder; > - struct folio *folio = slab_folio(slab); > - > - BUG_ON(!folio_test_slab(folio)); > - __slab_clear_pfmemalloc(slab); > - page_mapcount_reset(&folio->page); > - folio->mapping = NULL; > - /* Make the mapping reset visible before clearing the flag */ > - smp_wmb(); > - __folio_clear_slab(folio); > - > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += 1 << order; > - unaccount_slab(slab, order, cachep); > - __free_pages(&folio->page, order); > -} > - > -static void kmem_rcu_free(struct rcu_head *head) > -{ > - struct kmem_cache *cachep; > - struct slab *slab; > - > - slab = container_of(head, struct slab, rcu_head); > - cachep = slab->slab_cache; > - > - kmem_freepages(cachep, slab); > -} > - > -#if DEBUG > -static inline bool is_debug_pagealloc_cache(struct kmem_cache *cachep) > -{ > - return debug_pagealloc_enabled_static() && OFF_SLAB(cachep) && > - ((cachep->size % PAGE_SIZE) == 0); > -} > - > -#ifdef CONFIG_DEBUG_PAGEALLOC > -static void slab_kernel_map(struct kmem_cache *cachep, void *objp, int map) > -{ > - if (!is_debug_pagealloc_cache(cachep)) > - return; > - > - __kernel_map_pages(virt_to_page(objp), cachep->size / PAGE_SIZE, map); > -} > - > -#else > -static inline void slab_kernel_map(struct kmem_cache *cachep, void *objp, > - int map) {} > - > -#endif > - > -static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val) > -{ > - int size = cachep->object_size; > - addr = &((char *)addr)[obj_offset(cachep)]; > - > - memset(addr, val, size); > - *(unsigned char *)(addr + size - 1) = POISON_END; > -} > - > -static void dump_line(char *data, int offset, int limit) > -{ > - int i; > - unsigned char error = 0; > - int bad_count = 0; > - > - pr_err("%03x: ", offset); > - for (i = 0; i < limit; i++) { > - if (data[offset + i] != POISON_FREE) { > - error = data[offset + i]; > - bad_count++; > - } > - } > - print_hex_dump(KERN_CONT, "", 0, 16, 1, > - &data[offset], limit, 1); > - > - if (bad_count == 1) { > - error ^= POISON_FREE; > - if (!(error & (error - 1))) { > - pr_err("Single bit error detected. Probably bad RAM.\n"); > -#ifdef CONFIG_X86 > - pr_err("Run memtest86+ or a similar memory test tool.\n"); > -#else > - pr_err("Run a memory test tool.\n"); > -#endif > - } > - } > -} > -#endif > - > -#if DEBUG > - > -static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines) > -{ > - int i, size; > - char *realobj; > - > - if (cachep->flags & SLAB_RED_ZONE) { > - pr_err("Redzone: 0x%llx/0x%llx\n", > - *dbg_redzone1(cachep, objp), > - *dbg_redzone2(cachep, objp)); > - } > - > - if (cachep->flags & SLAB_STORE_USER) > - pr_err("Last user: (%pSR)\n", *dbg_userword(cachep, objp)); > - realobj = (char *)objp + obj_offset(cachep); > - size = cachep->object_size; > - for (i = 0; i < size && lines; i += 16, lines--) { > - int limit; > - limit = 16; > - if (i + limit > size) > - limit = size - i; > - dump_line(realobj, i, limit); > - } > -} > - > -static void check_poison_obj(struct kmem_cache *cachep, void *objp) > -{ > - char *realobj; > - int size, i; > - int lines = 0; > - > - if (is_debug_pagealloc_cache(cachep)) > - return; > - > - realobj = (char *)objp + obj_offset(cachep); > - size = cachep->object_size; > - > - for (i = 0; i < size; i++) { > - char exp = POISON_FREE; > - if (i == size - 1) > - exp = POISON_END; > - if (realobj[i] != exp) { > - int limit; > - /* Mismatch ! */ > - /* Print header */ > - if (lines == 0) { > - pr_err("Slab corruption (%s): %s start=%px, len=%d\n", > - print_tainted(), cachep->name, > - realobj, size); > - print_objinfo(cachep, objp, 0); > - } > - /* Hexdump the affected line */ > - i = (i / 16) * 16; > - limit = 16; > - if (i + limit > size) > - limit = size - i; > - dump_line(realobj, i, limit); > - i += 16; > - lines++; > - /* Limit to 5 lines */ > - if (lines > 5) > - break; > - } > - } > - if (lines != 0) { > - /* Print some data about the neighboring objects, if they > - * exist: > - */ > - struct slab *slab = virt_to_slab(objp); > - unsigned int objnr; > - > - objnr = obj_to_index(cachep, slab, objp); > - if (objnr) { > - objp = index_to_obj(cachep, slab, objnr - 1); > - realobj = (char *)objp + obj_offset(cachep); > - pr_err("Prev obj: start=%px, len=%d\n", realobj, size); > - print_objinfo(cachep, objp, 2); > - } > - if (objnr + 1 < cachep->num) { > - objp = index_to_obj(cachep, slab, objnr + 1); > - realobj = (char *)objp + obj_offset(cachep); > - pr_err("Next obj: start=%px, len=%d\n", realobj, size); > - print_objinfo(cachep, objp, 2); > - } > - } > -} > -#endif > - > -#if DEBUG > -static void slab_destroy_debugcheck(struct kmem_cache *cachep, > - struct slab *slab) > -{ > - int i; > - > - if (OBJFREELIST_SLAB(cachep) && cachep->flags & SLAB_POISON) { > - poison_obj(cachep, slab->freelist - obj_offset(cachep), > - POISON_FREE); > - } > - > - for (i = 0; i < cachep->num; i++) { > - void *objp = index_to_obj(cachep, slab, i); > - > - if (cachep->flags & SLAB_POISON) { > - check_poison_obj(cachep, objp); > - slab_kernel_map(cachep, objp, 1); > - } > - if (cachep->flags & SLAB_RED_ZONE) { > - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "start of a freed object was overwritten"); > - if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "end of a freed object was overwritten"); > - } > - } > -} > -#else > -static void slab_destroy_debugcheck(struct kmem_cache *cachep, > - struct slab *slab) > -{ > -} > -#endif > - > -/** > - * slab_destroy - destroy and release all objects in a slab > - * @cachep: cache pointer being destroyed > - * @slab: slab being destroyed > - * > - * Destroy all the objs in a slab, and release the mem back to the system. > - * Before calling the slab must have been unlinked from the cache. The > - * kmem_cache_node ->list_lock is not held/needed. > - */ > -static void slab_destroy(struct kmem_cache *cachep, struct slab *slab) > -{ > - void *freelist; > - > - freelist = slab->freelist; > - slab_destroy_debugcheck(cachep, slab); > - if (unlikely(cachep->flags & SLAB_TYPESAFE_BY_RCU)) > - call_rcu(&slab->rcu_head, kmem_rcu_free); > - else > - kmem_freepages(cachep, slab); > - > - /* > - * From now on, we don't use freelist > - * although actual page can be freed in rcu context > - */ > - if (OFF_SLAB(cachep)) > - kfree(freelist); > -} > - > -/* > - * Update the size of the caches before calling slabs_destroy as it may > - * recursively call kfree. > - */ > -static void slabs_destroy(struct kmem_cache *cachep, struct list_head *list) > -{ > - struct slab *slab, *n; > - > - list_for_each_entry_safe(slab, n, list, slab_list) { > - list_del(&slab->slab_list); > - slab_destroy(cachep, slab); > - } > -} > - > -/** > - * calculate_slab_order - calculate size (page order) of slabs > - * @cachep: pointer to the cache that is being created > - * @size: size of objects to be created in this cache. > - * @flags: slab allocation flags > - * > - * Also calculates the number of objects per slab. > - * > - * This could be made much more intelligent. For now, try to avoid using > - * high order pages for slabs. When the gfp() functions are more friendly > - * towards high-order requests, this should be changed. > - * > - * Return: number of left-over bytes in a slab > - */ > -static size_t calculate_slab_order(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left_over = 0; > - int gfporder; > - > - for (gfporder = 0; gfporder <= KMALLOC_MAX_ORDER; gfporder++) { > - unsigned int num; > - size_t remainder; > - > - num = cache_estimate(gfporder, size, flags, &remainder); > - if (!num) > - continue; > - > - /* Can't handle number of objects more than SLAB_OBJ_MAX_NUM */ > - if (num > SLAB_OBJ_MAX_NUM) > - break; > - > - if (flags & CFLGS_OFF_SLAB) { > - struct kmem_cache *freelist_cache; > - size_t freelist_size; > - size_t freelist_cache_size; > - > - freelist_size = num * sizeof(freelist_idx_t); > - if (freelist_size > KMALLOC_MAX_CACHE_SIZE) { > - freelist_cache_size = PAGE_SIZE << get_order(freelist_size); > - } else { > - freelist_cache = kmalloc_slab(freelist_size, 0u); > - if (!freelist_cache) > - continue; > - freelist_cache_size = freelist_cache->size; > - > - /* > - * Needed to avoid possible looping condition > - * in cache_grow_begin() > - */ > - if (OFF_SLAB(freelist_cache)) > - continue; > - } > - > - /* check if off slab has enough benefit */ > - if (freelist_cache_size > cachep->size / 2) > - continue; > - } > - > - /* Found something acceptable - save it away */ > - cachep->num = num; > - cachep->gfporder = gfporder; > - left_over = remainder; > - > - /* > - * A VFS-reclaimable slab tends to have most allocations > - * as GFP_NOFS and we really don't want to have to be allocating > - * higher-order pages when we are unable to shrink dcache. > - */ > - if (flags & SLAB_RECLAIM_ACCOUNT) > - break; > - > - /* > - * Large number of objects is good, but very large slabs are > - * currently bad for the gfp()s. > - */ > - if (gfporder >= slab_max_order) > - break; > - > - /* > - * Acceptable internal fragmentation? > - */ > - if (left_over * 8 <= (PAGE_SIZE << gfporder)) > - break; > - } > - return left_over; > -} > - > -static struct array_cache __percpu *alloc_kmem_cache_cpus( > - struct kmem_cache *cachep, int entries, int batchcount) > -{ > - int cpu; > - size_t size; > - struct array_cache __percpu *cpu_cache; > - > - size = sizeof(void *) * entries + sizeof(struct array_cache); > - cpu_cache = __alloc_percpu(size, sizeof(void *)); > - > - if (!cpu_cache) > - return NULL; > - > - for_each_possible_cpu(cpu) { > - init_arraycache(per_cpu_ptr(cpu_cache, cpu), > - entries, batchcount); > - } > - > - return cpu_cache; > -} > - > -static int __ref setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp) > -{ > - if (slab_state >= FULL) > - return enable_cpucache(cachep, gfp); > - > - cachep->cpu_cache = alloc_kmem_cache_cpus(cachep, 1, 1); > - if (!cachep->cpu_cache) > - return 1; > - > - if (slab_state == DOWN) { > - /* Creation of first cache (kmem_cache). */ > - set_up_node(kmem_cache, CACHE_CACHE); > - } else if (slab_state == PARTIAL) { > - /* For kmem_cache_node */ > - set_up_node(cachep, SIZE_NODE); > - } else { > - int node; > - > - for_each_online_node(node) { > - cachep->node[node] = kmalloc_node( > - sizeof(struct kmem_cache_node), gfp, node); > - BUG_ON(!cachep->node[node]); > - kmem_cache_node_init(cachep->node[node]); > - } > - } > - > - cachep->node[numa_mem_id()]->next_reap = > - jiffies + REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - > - cpu_cache_get(cachep)->avail = 0; > - cpu_cache_get(cachep)->limit = BOOT_CPUCACHE_ENTRIES; > - cpu_cache_get(cachep)->batchcount = 1; > - cpu_cache_get(cachep)->touched = 0; > - cachep->batchcount = 1; > - cachep->limit = BOOT_CPUCACHE_ENTRIES; > - return 0; > -} > - > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name) > -{ > - return flags; > -} > - > -struct kmem_cache * > -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > - slab_flags_t flags, void (*ctor)(void *)) > -{ > - struct kmem_cache *cachep; > - > - cachep = find_mergeable(size, align, flags, name, ctor); > - if (cachep) { > - cachep->refcount++; > - > - /* > - * Adjust the object sizes so that we clear > - * the complete object on kzalloc. > - */ > - cachep->object_size = max_t(int, cachep->object_size, size); > - } > - return cachep; > -} > - > -static bool set_objfreelist_slab_cache(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left; > - > - cachep->num = 0; > - > - /* > - * If slab auto-initialization on free is enabled, store the freelist > - * off-slab, so that its contents don't end up in one of the allocated > - * objects. > - */ > - if (unlikely(slab_want_init_on_free(cachep))) > - return false; > - > - if (cachep->ctor || flags & SLAB_TYPESAFE_BY_RCU) > - return false; > - > - left = calculate_slab_order(cachep, size, > - flags | CFLGS_OBJFREELIST_SLAB); > - if (!cachep->num) > - return false; > - > - if (cachep->num * sizeof(freelist_idx_t) > cachep->object_size) > - return false; > - > - cachep->colour = left / cachep->colour_off; > - > - return true; > -} > - > -static bool set_off_slab_cache(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left; > - > - cachep->num = 0; > - > - /* > - * Always use on-slab management when SLAB_NOLEAKTRACE > - * to avoid recursive calls into kmemleak. > - */ > - if (flags & SLAB_NOLEAKTRACE) > - return false; > - > - /* > - * Size is large, assume best to place the slab management obj > - * off-slab (should allow better packing of objs). > - */ > - left = calculate_slab_order(cachep, size, flags | CFLGS_OFF_SLAB); > - if (!cachep->num) > - return false; > - > - /* > - * If the slab has been placed off-slab, and we have enough space then > - * move it on-slab. This is at the expense of any extra colouring. > - */ > - if (left >= cachep->num * sizeof(freelist_idx_t)) > - return false; > - > - cachep->colour = left / cachep->colour_off; > - > - return true; > -} > - > -static bool set_on_slab_cache(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left; > - > - cachep->num = 0; > - > - left = calculate_slab_order(cachep, size, flags); > - if (!cachep->num) > - return false; > - > - cachep->colour = left / cachep->colour_off; > - > - return true; > -} > - > -/** > - * __kmem_cache_create - Create a cache. > - * @cachep: cache management descriptor > - * @flags: SLAB flags > - * > - * Returns a ptr to the cache on success, NULL on failure. > - * Cannot be called within an int, but can be interrupted. > - * The @ctor is run when new pages are allocated by the cache. > - * > - * The flags are > - * > - * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5) > - * to catch references to uninitialised memory. > - * > - * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check > - * for buffer overruns. > - * > - * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware > - * cacheline. This can be beneficial if you're counting cycles as closely > - * as davem. > - * > - * Return: a pointer to the created cache or %NULL in case of error > - */ > -int __kmem_cache_create(struct kmem_cache *cachep, slab_flags_t flags) > -{ > - size_t ralign = BYTES_PER_WORD; > - gfp_t gfp; > - int err; > - unsigned int size = cachep->size; > - > -#if DEBUG > -#if FORCED_DEBUG > - /* > - * Enable redzoning and last user accounting, except for caches with > - * large objects, if the increased size would increase the object size > - * above the next power of two: caches with object sizes just above a > - * power of two have a significant amount of internal fragmentation. > - */ > - if (size < 4096 || fls(size - 1) == fls(size-1 + REDZONE_ALIGN + > - 2 * sizeof(unsigned long long))) > - flags |= SLAB_RED_ZONE | SLAB_STORE_USER; > - if (!(flags & SLAB_TYPESAFE_BY_RCU)) > - flags |= SLAB_POISON; > -#endif > -#endif > - > - /* > - * Check that size is in terms of words. This is needed to avoid > - * unaligned accesses for some archs when redzoning is used, and makes > - * sure any on-slab bufctl's are also correctly aligned. > - */ > - size = ALIGN(size, BYTES_PER_WORD); > - > - if (flags & SLAB_RED_ZONE) { > - ralign = REDZONE_ALIGN; > - /* If redzoning, ensure that the second redzone is suitably > - * aligned, by adjusting the object size accordingly. */ > - size = ALIGN(size, REDZONE_ALIGN); > - } > - > - /* 3) caller mandated alignment */ > - if (ralign < cachep->align) { > - ralign = cachep->align; > - } > - /* disable debug if necessary */ > - if (ralign > __alignof__(unsigned long long)) > - flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); > - /* > - * 4) Store it. > - */ > - cachep->align = ralign; > - cachep->colour_off = cache_line_size(); > - /* Offset must be a multiple of the alignment. */ > - if (cachep->colour_off < cachep->align) > - cachep->colour_off = cachep->align; > - > - if (slab_is_available()) > - gfp = GFP_KERNEL; > - else > - gfp = GFP_NOWAIT; > - > -#if DEBUG > - > - /* > - * Both debugging options require word-alignment which is calculated > - * into align above. > - */ > - if (flags & SLAB_RED_ZONE) { > - /* add space for red zone words */ > - cachep->obj_offset += sizeof(unsigned long long); > - size += 2 * sizeof(unsigned long long); > - } > - if (flags & SLAB_STORE_USER) { > - /* user store requires one word storage behind the end of > - * the real object. But if the second red zone needs to be > - * aligned to 64 bits, we must allow that much space. > - */ > - if (flags & SLAB_RED_ZONE) > - size += REDZONE_ALIGN; > - else > - size += BYTES_PER_WORD; > - } > -#endif > - > - kasan_cache_create(cachep, &size, &flags); > - > - size = ALIGN(size, cachep->align); > - /* > - * We should restrict the number of objects in a slab to implement > - * byte sized index. Refer comment on SLAB_OBJ_MIN_SIZE definition. > - */ > - if (FREELIST_BYTE_INDEX && size < SLAB_OBJ_MIN_SIZE) > - size = ALIGN(SLAB_OBJ_MIN_SIZE, cachep->align); > - > -#if DEBUG > - /* > - * To activate debug pagealloc, off-slab management is necessary > - * requirement. In early phase of initialization, small sized slab > - * doesn't get initialized so it would not be possible. So, we need > - * to check size >= 256. It guarantees that all necessary small > - * sized slab is initialized in current slab initialization sequence. > - */ > - if (debug_pagealloc_enabled_static() && (flags & SLAB_POISON) && > - size >= 256 && cachep->object_size > cache_line_size()) { > - if (size < PAGE_SIZE || size % PAGE_SIZE == 0) { > - size_t tmp_size = ALIGN(size, PAGE_SIZE); > - > - if (set_off_slab_cache(cachep, tmp_size, flags)) { > - flags |= CFLGS_OFF_SLAB; > - cachep->obj_offset += tmp_size - size; > - size = tmp_size; > - goto done; > - } > - } > - } > -#endif > - > - if (set_objfreelist_slab_cache(cachep, size, flags)) { > - flags |= CFLGS_OBJFREELIST_SLAB; > - goto done; > - } > - > - if (set_off_slab_cache(cachep, size, flags)) { > - flags |= CFLGS_OFF_SLAB; > - goto done; > - } > - > - if (set_on_slab_cache(cachep, size, flags)) > - goto done; > - > - return -E2BIG; > - > -done: > - cachep->freelist_size = cachep->num * sizeof(freelist_idx_t); > - cachep->flags = flags; > - cachep->allocflags = __GFP_COMP; > - if (flags & SLAB_CACHE_DMA) > - cachep->allocflags |= GFP_DMA; > - if (flags & SLAB_CACHE_DMA32) > - cachep->allocflags |= GFP_DMA32; > - if (flags & SLAB_RECLAIM_ACCOUNT) > - cachep->allocflags |= __GFP_RECLAIMABLE; > - cachep->size = size; > - cachep->reciprocal_buffer_size = reciprocal_value(size); > - > -#if DEBUG > - /* > - * If we're going to use the generic kernel_map_pages() > - * poisoning, then it's going to smash the contents of > - * the redzone and userword anyhow, so switch them off. > - */ > - if (IS_ENABLED(CONFIG_PAGE_POISONING) && > - (cachep->flags & SLAB_POISON) && > - is_debug_pagealloc_cache(cachep)) > - cachep->flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); > -#endif > - > - err = setup_cpu_cache(cachep, gfp); > - if (err) { > - __kmem_cache_release(cachep); > - return err; > - } > - > - return 0; > -} > - > -#if DEBUG > -static void check_irq_off(void) > -{ > - BUG_ON(!irqs_disabled()); > -} > - > -static void check_irq_on(void) > -{ > - BUG_ON(irqs_disabled()); > -} > - > -static void check_mutex_acquired(void) > -{ > - BUG_ON(!mutex_is_locked(&slab_mutex)); > -} > - > -static void check_spinlock_acquired(struct kmem_cache *cachep) > -{ > -#ifdef CONFIG_SMP > - check_irq_off(); > - assert_raw_spin_locked(&get_node(cachep, numa_mem_id())->list_lock); > -#endif > -} > - > -static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node) > -{ > -#ifdef CONFIG_SMP > - check_irq_off(); > - assert_raw_spin_locked(&get_node(cachep, node)->list_lock); > -#endif > -} > - > -#else > -#define check_irq_off() do { } while(0) > -#define check_irq_on() do { } while(0) > -#define check_mutex_acquired() do { } while(0) > -#define check_spinlock_acquired(x) do { } while(0) > -#define check_spinlock_acquired_node(x, y) do { } while(0) > -#endif > - > -static void drain_array_locked(struct kmem_cache *cachep, struct array_cache *ac, > - int node, bool free_all, struct list_head *list) > -{ > - int tofree; > - > - if (!ac || !ac->avail) > - return; > - > - tofree = free_all ? ac->avail : (ac->limit + 4) / 5; > - if (tofree > ac->avail) > - tofree = (ac->avail + 1) / 2; > - > - free_block(cachep, ac->entry, tofree, node, list); > - ac->avail -= tofree; > - memmove(ac->entry, &(ac->entry[tofree]), sizeof(void *) * ac->avail); > -} > - > -static void do_drain(void *arg) > -{ > - struct kmem_cache *cachep = arg; > - struct array_cache *ac; > - int node = numa_mem_id(); > - struct kmem_cache_node *n; > - LIST_HEAD(list); > - > - check_irq_off(); > - ac = cpu_cache_get(cachep); > - n = get_node(cachep, node); > - raw_spin_lock(&n->list_lock); > - free_block(cachep, ac->entry, ac->avail, node, &list); > - raw_spin_unlock(&n->list_lock); > - ac->avail = 0; > - slabs_destroy(cachep, &list); > -} > - > -static void drain_cpu_caches(struct kmem_cache *cachep) > -{ > - struct kmem_cache_node *n; > - int node; > - LIST_HEAD(list); > - > - on_each_cpu(do_drain, cachep, 1); > - check_irq_on(); > - for_each_kmem_cache_node(cachep, node, n) > - if (n->alien) > - drain_alien_cache(cachep, n->alien); > - > - for_each_kmem_cache_node(cachep, node, n) { > - raw_spin_lock_irq(&n->list_lock); > - drain_array_locked(cachep, n->shared, node, true, &list); > - raw_spin_unlock_irq(&n->list_lock); > - > - slabs_destroy(cachep, &list); > - } > -} > - > -/* > - * Remove slabs from the list of free slabs. > - * Specify the number of slabs to drain in tofree. > - * > - * Returns the actual number of slabs released. > - */ > -static int drain_freelist(struct kmem_cache *cache, > - struct kmem_cache_node *n, int tofree) > -{ > - struct list_head *p; > - int nr_freed; > - struct slab *slab; > - > - nr_freed = 0; > - while (nr_freed < tofree && !list_empty(&n->slabs_free)) { > - > - raw_spin_lock_irq(&n->list_lock); > - p = n->slabs_free.prev; > - if (p == &n->slabs_free) { > - raw_spin_unlock_irq(&n->list_lock); > - goto out; > - } > - > - slab = list_entry(p, struct slab, slab_list); > - list_del(&slab->slab_list); > - n->free_slabs--; > - n->total_slabs--; > - /* > - * Safe to drop the lock. The slab is no longer linked > - * to the cache. > - */ > - n->free_objects -= cache->num; > - raw_spin_unlock_irq(&n->list_lock); > - slab_destroy(cache, slab); > - nr_freed++; > - > - cond_resched(); > - } > -out: > - return nr_freed; > -} > - > -bool __kmem_cache_empty(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) > - if (!list_empty(&n->slabs_full) || > - !list_empty(&n->slabs_partial)) > - return false; > - return true; > -} > - > -int __kmem_cache_shrink(struct kmem_cache *cachep) > -{ > - int ret = 0; > - int node; > - struct kmem_cache_node *n; > - > - drain_cpu_caches(cachep); > - > - check_irq_on(); > - for_each_kmem_cache_node(cachep, node, n) { > - drain_freelist(cachep, n, INT_MAX); > - > - ret += !list_empty(&n->slabs_full) || > - !list_empty(&n->slabs_partial); > - } > - return (ret ? 1 : 0); > -} > - > -int __kmem_cache_shutdown(struct kmem_cache *cachep) > -{ > - return __kmem_cache_shrink(cachep); > -} > - > -void __kmem_cache_release(struct kmem_cache *cachep) > -{ > - int i; > - struct kmem_cache_node *n; > - > - cache_random_seq_destroy(cachep); > - > - free_percpu(cachep->cpu_cache); > - > - /* NUMA: free the node structures */ > - for_each_kmem_cache_node(cachep, i, n) { > - kfree(n->shared); > - free_alien_cache(n->alien); > - kfree(n); > - cachep->node[i] = NULL; > - } > -} > - > -/* > - * Get the memory for a slab management obj. > - * > - * For a slab cache when the slab descriptor is off-slab, the > - * slab descriptor can't come from the same cache which is being created, > - * Because if it is the case, that means we defer the creation of > - * the kmalloc_{dma,}_cache of size sizeof(slab descriptor) to this point. > - * And we eventually call down to __kmem_cache_create(), which > - * in turn looks up in the kmalloc_{dma,}_caches for the desired-size one. > - * This is a "chicken-and-egg" problem. > - * > - * So the off-slab slab descriptor shall come from the kmalloc_{dma,}_caches, > - * which are all initialized during kmem_cache_init(). > - */ > -static void *alloc_slabmgmt(struct kmem_cache *cachep, > - struct slab *slab, int colour_off, > - gfp_t local_flags, int nodeid) > -{ > - void *freelist; > - void *addr = slab_address(slab); > - > - slab->s_mem = addr + colour_off; > - slab->active = 0; > - > - if (OBJFREELIST_SLAB(cachep)) > - freelist = NULL; > - else if (OFF_SLAB(cachep)) { > - /* Slab management obj is off-slab. */ > - freelist = kmalloc_node(cachep->freelist_size, > - local_flags, nodeid); > - } else { > - /* We will use last bytes at the slab for freelist */ > - freelist = addr + (PAGE_SIZE << cachep->gfporder) - > - cachep->freelist_size; > - } > - > - return freelist; > -} > - > -static inline freelist_idx_t get_free_obj(struct slab *slab, unsigned int idx) > -{ > - return ((freelist_idx_t *) slab->freelist)[idx]; > -} > - > -static inline void set_free_obj(struct slab *slab, > - unsigned int idx, freelist_idx_t val) > -{ > - ((freelist_idx_t *)(slab->freelist))[idx] = val; > -} > - > -static void cache_init_objs_debug(struct kmem_cache *cachep, struct slab *slab) > -{ > -#if DEBUG > - int i; > - > - for (i = 0; i < cachep->num; i++) { > - void *objp = index_to_obj(cachep, slab, i); > - > - if (cachep->flags & SLAB_STORE_USER) > - *dbg_userword(cachep, objp) = NULL; > - > - if (cachep->flags & SLAB_RED_ZONE) { > - *dbg_redzone1(cachep, objp) = RED_INACTIVE; > - *dbg_redzone2(cachep, objp) = RED_INACTIVE; > - } > - /* > - * Constructors are not allowed to allocate memory from the same > - * cache which they are a constructor for. Otherwise, deadlock. > - * They must also be threaded. > - */ > - if (cachep->ctor && !(cachep->flags & SLAB_POISON)) { > - kasan_unpoison_object_data(cachep, > - objp + obj_offset(cachep)); > - cachep->ctor(objp + obj_offset(cachep)); > - kasan_poison_object_data( > - cachep, objp + obj_offset(cachep)); > - } > - > - if (cachep->flags & SLAB_RED_ZONE) { > - if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "constructor overwrote the end of an object"); > - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "constructor overwrote the start of an object"); > - } > - /* need to poison the objs? */ > - if (cachep->flags & SLAB_POISON) { > - poison_obj(cachep, objp, POISON_FREE); > - slab_kernel_map(cachep, objp, 0); > - } > - } > -#endif > -} > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -/* Hold information during a freelist initialization */ > -union freelist_init_state { > - struct { > - unsigned int pos; > - unsigned int *list; > - unsigned int count; > - }; > - struct rnd_state rnd_state; > -}; > - > -/* > - * Initialize the state based on the randomization method available. > - * return true if the pre-computed list is available, false otherwise. > - */ > -static bool freelist_state_initialize(union freelist_init_state *state, > - struct kmem_cache *cachep, > - unsigned int count) > -{ > - bool ret; > - unsigned int rand; > - > - /* Use best entropy available to define a random shift */ > - rand = get_random_u32(); > - > - /* Use a random state if the pre-computed list is not available */ > - if (!cachep->random_seq) { > - prandom_seed_state(&state->rnd_state, rand); > - ret = false; > - } else { > - state->list = cachep->random_seq; > - state->count = count; > - state->pos = rand % count; > - ret = true; > - } > - return ret; > -} > - > -/* Get the next entry on the list and randomize it using a random shift */ > -static freelist_idx_t next_random_slot(union freelist_init_state *state) > -{ > - if (state->pos >= state->count) > - state->pos = 0; > - return state->list[state->pos++]; > -} > - > -/* Swap two freelist entries */ > -static void swap_free_obj(struct slab *slab, unsigned int a, unsigned int b) > -{ > - swap(((freelist_idx_t *) slab->freelist)[a], > - ((freelist_idx_t *) slab->freelist)[b]); > -} > - > -/* > - * Shuffle the freelist initialization state based on pre-computed lists. > - * return true if the list was successfully shuffled, false otherwise. > - */ > -static bool shuffle_freelist(struct kmem_cache *cachep, struct slab *slab) > -{ > - unsigned int objfreelist = 0, i, rand, count = cachep->num; > - union freelist_init_state state; > - bool precomputed; > - > - if (count < 2) > - return false; > - > - precomputed = freelist_state_initialize(&state, cachep, count); > - > - /* Take a random entry as the objfreelist */ > - if (OBJFREELIST_SLAB(cachep)) { > - if (!precomputed) > - objfreelist = count - 1; > - else > - objfreelist = next_random_slot(&state); > - slab->freelist = index_to_obj(cachep, slab, objfreelist) + > - obj_offset(cachep); > - count--; > - } > - > - /* > - * On early boot, generate the list dynamically. > - * Later use a pre-computed list for speed. > - */ > - if (!precomputed) { > - for (i = 0; i < count; i++) > - set_free_obj(slab, i, i); > - > - /* Fisher-Yates shuffle */ > - for (i = count - 1; i > 0; i--) { > - rand = prandom_u32_state(&state.rnd_state); > - rand %= (i + 1); > - swap_free_obj(slab, i, rand); > - } > - } else { > - for (i = 0; i < count; i++) > - set_free_obj(slab, i, next_random_slot(&state)); > - } > - > - if (OBJFREELIST_SLAB(cachep)) > - set_free_obj(slab, cachep->num - 1, objfreelist); > - > - return true; > -} > -#else > -static inline bool shuffle_freelist(struct kmem_cache *cachep, > - struct slab *slab) > -{ > - return false; > -} > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > - > -static void cache_init_objs(struct kmem_cache *cachep, > - struct slab *slab) > -{ > - int i; > - void *objp; > - bool shuffled; > - > - cache_init_objs_debug(cachep, slab); > - > - /* Try to randomize the freelist if enabled */ > - shuffled = shuffle_freelist(cachep, slab); > - > - if (!shuffled && OBJFREELIST_SLAB(cachep)) { > - slab->freelist = index_to_obj(cachep, slab, cachep->num - 1) + > - obj_offset(cachep); > - } > - > - for (i = 0; i < cachep->num; i++) { > - objp = index_to_obj(cachep, slab, i); > - objp = kasan_init_slab_obj(cachep, objp); > - > - /* constructor could break poison info */ > - if (DEBUG == 0 && cachep->ctor) { > - kasan_unpoison_object_data(cachep, objp); > - cachep->ctor(objp); > - kasan_poison_object_data(cachep, objp); > - } > - > - if (!shuffled) > - set_free_obj(slab, i, i); > - } > -} > - > -static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slab) > -{ > - void *objp; > - > - objp = index_to_obj(cachep, slab, get_free_obj(slab, slab->active)); > - slab->active++; > - > - return objp; > -} > - > -static void slab_put_obj(struct kmem_cache *cachep, > - struct slab *slab, void *objp) > -{ > - unsigned int objnr = obj_to_index(cachep, slab, objp); > -#if DEBUG > - unsigned int i; > - > - /* Verify double free bug */ > - for (i = slab->active; i < cachep->num; i++) { > - if (get_free_obj(slab, i) == objnr) { > - pr_err("slab: double free detected in cache '%s', objp %px\n", > - cachep->name, objp); > - BUG(); > - } > - } > -#endif > - slab->active--; > - if (!slab->freelist) > - slab->freelist = objp + obj_offset(cachep); > - > - set_free_obj(slab, slab->active, objnr); > -} > - > -/* > - * Grow (by 1) the number of slabs within a cache. This is called by > - * kmem_cache_alloc() when there are no active objs left in a cache. > - */ > -static struct slab *cache_grow_begin(struct kmem_cache *cachep, > - gfp_t flags, int nodeid) > -{ > - void *freelist; > - size_t offset; > - gfp_t local_flags; > - int slab_node; > - struct kmem_cache_node *n; > - struct slab *slab; > - > - /* > - * Be lazy and only check for valid flags here, keeping it out of the > - * critical path in kmem_cache_alloc(). > - */ > - if (unlikely(flags & GFP_SLAB_BUG_MASK)) > - flags = kmalloc_fix_flags(flags); > - > - WARN_ON_ONCE(cachep->ctor && (flags & __GFP_ZERO)); > - local_flags = flags & (GFP_CONSTRAINT_MASK|GFP_RECLAIM_MASK); > - > - check_irq_off(); > - if (gfpflags_allow_blocking(local_flags)) > - local_irq_enable(); > - > - /* > - * Get mem for the objs. Attempt to allocate a physical page from > - * 'nodeid'. > - */ > - slab = kmem_getpages(cachep, local_flags, nodeid); > - if (!slab) > - goto failed; > - > - slab_node = slab_nid(slab); > - n = get_node(cachep, slab_node); > - > - /* Get colour for the slab, and cal the next value. */ > - n->colour_next++; > - if (n->colour_next >= cachep->colour) > - n->colour_next = 0; > - > - offset = n->colour_next; > - if (offset >= cachep->colour) > - offset = 0; > - > - offset *= cachep->colour_off; > - > - /* > - * Call kasan_poison_slab() before calling alloc_slabmgmt(), so > - * page_address() in the latter returns a non-tagged pointer, > - * as it should be for slab pages. > - */ > - kasan_poison_slab(slab); > - > - /* Get slab management. */ > - freelist = alloc_slabmgmt(cachep, slab, offset, > - local_flags & ~GFP_CONSTRAINT_MASK, slab_node); > - if (OFF_SLAB(cachep) && !freelist) > - goto opps1; > - > - slab->slab_cache = cachep; > - slab->freelist = freelist; > - > - cache_init_objs(cachep, slab); > - > - if (gfpflags_allow_blocking(local_flags)) > - local_irq_disable(); > - > - return slab; > - > -opps1: > - kmem_freepages(cachep, slab); > -failed: > - if (gfpflags_allow_blocking(local_flags)) > - local_irq_disable(); > - return NULL; > -} > - > -static void cache_grow_end(struct kmem_cache *cachep, struct slab *slab) > -{ > - struct kmem_cache_node *n; > - void *list = NULL; > - > - check_irq_off(); > - > - if (!slab) > - return; > - > - INIT_LIST_HEAD(&slab->slab_list); > - n = get_node(cachep, slab_nid(slab)); > - > - raw_spin_lock(&n->list_lock); > - n->total_slabs++; > - if (!slab->active) { > - list_add_tail(&slab->slab_list, &n->slabs_free); > - n->free_slabs++; > - } else > - fixup_slab_list(cachep, n, slab, &list); > - > - STATS_INC_GROWN(cachep); > - n->free_objects += cachep->num - slab->active; > - raw_spin_unlock(&n->list_lock); > - > - fixup_objfreelist_debug(cachep, &list); > -} > - > -#if DEBUG > - > -/* > - * Perform extra freeing checks: > - * - detect bad pointers. > - * - POISON/RED_ZONE checking > - */ > -static void kfree_debugcheck(const void *objp) > -{ > - if (!virt_addr_valid(objp)) { > - pr_err("kfree_debugcheck: out of range ptr %lxh\n", > - (unsigned long)objp); > - BUG(); > - } > -} > - > -static inline void verify_redzone_free(struct kmem_cache *cache, void *obj) > -{ > - unsigned long long redzone1, redzone2; > - > - redzone1 = *dbg_redzone1(cache, obj); > - redzone2 = *dbg_redzone2(cache, obj); > - > - /* > - * Redzone is ok. > - */ > - if (redzone1 == RED_ACTIVE && redzone2 == RED_ACTIVE) > - return; > - > - if (redzone1 == RED_INACTIVE && redzone2 == RED_INACTIVE) > - slab_error(cache, "double free detected"); > - else > - slab_error(cache, "memory outside object was overwritten"); > - > - pr_err("%px: redzone 1:0x%llx, redzone 2:0x%llx\n", > - obj, redzone1, redzone2); > -} > - > -static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - unsigned int objnr; > - struct slab *slab; > - > - BUG_ON(virt_to_cache(objp) != cachep); > - > - objp -= obj_offset(cachep); > - kfree_debugcheck(objp); > - slab = virt_to_slab(objp); > - > - if (cachep->flags & SLAB_RED_ZONE) { > - verify_redzone_free(cachep, objp); > - *dbg_redzone1(cachep, objp) = RED_INACTIVE; > - *dbg_redzone2(cachep, objp) = RED_INACTIVE; > - } > - if (cachep->flags & SLAB_STORE_USER) > - *dbg_userword(cachep, objp) = (void *)caller; > - > - objnr = obj_to_index(cachep, slab, objp); > - > - BUG_ON(objnr >= cachep->num); > - BUG_ON(objp != index_to_obj(cachep, slab, objnr)); > - > - if (cachep->flags & SLAB_POISON) { > - poison_obj(cachep, objp, POISON_FREE); > - slab_kernel_map(cachep, objp, 0); > - } > - return objp; > -} > - > -#else > -#define kfree_debugcheck(x) do { } while(0) > -#define cache_free_debugcheck(x, objp, z) (objp) > -#endif > - > -static inline void fixup_objfreelist_debug(struct kmem_cache *cachep, > - void **list) > -{ > -#if DEBUG > - void *next = *list; > - void *objp; > - > - while (next) { > - objp = next - obj_offset(cachep); > - next = *(void **)next; > - poison_obj(cachep, objp, POISON_FREE); > - } > -#endif > -} > - > -static inline void fixup_slab_list(struct kmem_cache *cachep, > - struct kmem_cache_node *n, struct slab *slab, > - void **list) > -{ > - /* move slabp to correct slabp list: */ > - list_del(&slab->slab_list); > - if (slab->active == cachep->num) { > - list_add(&slab->slab_list, &n->slabs_full); > - if (OBJFREELIST_SLAB(cachep)) { > -#if DEBUG > - /* Poisoning will be done without holding the lock */ > - if (cachep->flags & SLAB_POISON) { > - void **objp = slab->freelist; > - > - *objp = *list; > - *list = objp; > - } > -#endif > - slab->freelist = NULL; > - } > - } else > - list_add(&slab->slab_list, &n->slabs_partial); > -} > - > -/* Try to find non-pfmemalloc slab if needed */ > -static noinline struct slab *get_valid_first_slab(struct kmem_cache_node *n, > - struct slab *slab, bool pfmemalloc) > -{ > - if (!slab) > - return NULL; > - > - if (pfmemalloc) > - return slab; > - > - if (!slab_test_pfmemalloc(slab)) > - return slab; > - > - /* No need to keep pfmemalloc slab if we have enough free objects */ > - if (n->free_objects > n->free_limit) { > - slab_clear_pfmemalloc(slab); > - return slab; > - } > - > - /* Move pfmemalloc slab to the end of list to speed up next search */ > - list_del(&slab->slab_list); > - if (!slab->active) { > - list_add_tail(&slab->slab_list, &n->slabs_free); > - n->free_slabs++; > - } else > - list_add_tail(&slab->slab_list, &n->slabs_partial); > - > - list_for_each_entry(slab, &n->slabs_partial, slab_list) { > - if (!slab_test_pfmemalloc(slab)) > - return slab; > - } > - > - n->free_touched = 1; > - list_for_each_entry(slab, &n->slabs_free, slab_list) { > - if (!slab_test_pfmemalloc(slab)) { > - n->free_slabs--; > - return slab; > - } > - } > - > - return NULL; > -} > - > -static struct slab *get_first_slab(struct kmem_cache_node *n, bool pfmemalloc) > -{ > - struct slab *slab; > - > - assert_raw_spin_locked(&n->list_lock); > - slab = list_first_entry_or_null(&n->slabs_partial, struct slab, > - slab_list); > - if (!slab) { > - n->free_touched = 1; > - slab = list_first_entry_or_null(&n->slabs_free, struct slab, > - slab_list); > - if (slab) > - n->free_slabs--; > - } > - > - if (sk_memalloc_socks()) > - slab = get_valid_first_slab(n, slab, pfmemalloc); > - > - return slab; > -} > - > -static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep, > - struct kmem_cache_node *n, gfp_t flags) > -{ > - struct slab *slab; > - void *obj; > - void *list = NULL; > - > - if (!gfp_pfmemalloc_allowed(flags)) > - return NULL; > - > - raw_spin_lock(&n->list_lock); > - slab = get_first_slab(n, true); > - if (!slab) { > - raw_spin_unlock(&n->list_lock); > - return NULL; > - } > - > - obj = slab_get_obj(cachep, slab); > - n->free_objects--; > - > - fixup_slab_list(cachep, n, slab, &list); > - > - raw_spin_unlock(&n->list_lock); > - fixup_objfreelist_debug(cachep, &list); > - > - return obj; > -} > - > -/* > - * Slab list should be fixed up by fixup_slab_list() for existing slab > - * or cache_grow_end() for new slab > - */ > -static __always_inline int alloc_block(struct kmem_cache *cachep, > - struct array_cache *ac, struct slab *slab, int batchcount) > -{ > - /* > - * There must be at least one object available for > - * allocation. > - */ > - BUG_ON(slab->active >= cachep->num); > - > - while (slab->active < cachep->num && batchcount--) { > - STATS_INC_ALLOCED(cachep); > - STATS_INC_ACTIVE(cachep); > - STATS_SET_HIGH(cachep); > - > - ac->entry[ac->avail++] = slab_get_obj(cachep, slab); > - } > - > - return batchcount; > -} > - > -static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags) > -{ > - int batchcount; > - struct kmem_cache_node *n; > - struct array_cache *ac, *shared; > - int node; > - void *list = NULL; > - struct slab *slab; > - > - check_irq_off(); > - node = numa_mem_id(); > - > - ac = cpu_cache_get(cachep); > - batchcount = ac->batchcount; > - if (!ac->touched && batchcount > BATCHREFILL_LIMIT) { > - /* > - * If there was little recent activity on this cache, then > - * perform only a partial refill. Otherwise we could generate > - * refill bouncing. > - */ > - batchcount = BATCHREFILL_LIMIT; > - } > - n = get_node(cachep, node); > - > - BUG_ON(ac->avail > 0 || !n); > - shared = READ_ONCE(n->shared); > - if (!n->free_objects && (!shared || !shared->avail)) > - goto direct_grow; > - > - raw_spin_lock(&n->list_lock); > - shared = READ_ONCE(n->shared); > - > - /* See if we can refill from the shared array */ > - if (shared && transfer_objects(ac, shared, batchcount)) { > - shared->touched = 1; > - goto alloc_done; > - } > - > - while (batchcount > 0) { > - /* Get slab alloc is to come from. */ > - slab = get_first_slab(n, false); > - if (!slab) > - goto must_grow; > - > - check_spinlock_acquired(cachep); > - > - batchcount = alloc_block(cachep, ac, slab, batchcount); > - fixup_slab_list(cachep, n, slab, &list); > - } > - > -must_grow: > - n->free_objects -= ac->avail; > -alloc_done: > - raw_spin_unlock(&n->list_lock); > - fixup_objfreelist_debug(cachep, &list); > - > -direct_grow: > - if (unlikely(!ac->avail)) { > - /* Check if we can use obj in pfmemalloc slab */ > - if (sk_memalloc_socks()) { > - void *obj = cache_alloc_pfmemalloc(cachep, n, flags); > - > - if (obj) > - return obj; > - } > - > - slab = cache_grow_begin(cachep, gfp_exact_node(flags), node); > - > - /* > - * cache_grow_begin() can reenable interrupts, > - * then ac could change. > - */ > - ac = cpu_cache_get(cachep); > - if (!ac->avail && slab) > - alloc_block(cachep, ac, slab, batchcount); > - cache_grow_end(cachep, slab); > - > - if (!ac->avail) > - return NULL; > - } > - ac->touched = 1; > - > - return ac->entry[--ac->avail]; > -} > - > -#if DEBUG > -static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, > - gfp_t flags, void *objp, unsigned long caller) > -{ > - WARN_ON_ONCE(cachep->ctor && (flags & __GFP_ZERO)); > - if (!objp || is_kfence_address(objp)) > - return objp; > - if (cachep->flags & SLAB_POISON) { > - check_poison_obj(cachep, objp); > - slab_kernel_map(cachep, objp, 1); > - poison_obj(cachep, objp, POISON_INUSE); > - } > - if (cachep->flags & SLAB_STORE_USER) > - *dbg_userword(cachep, objp) = (void *)caller; > - > - if (cachep->flags & SLAB_RED_ZONE) { > - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE || > - *dbg_redzone2(cachep, objp) != RED_INACTIVE) { > - slab_error(cachep, "double free, or memory outside object was overwritten"); > - pr_err("%px: redzone 1:0x%llx, redzone 2:0x%llx\n", > - objp, *dbg_redzone1(cachep, objp), > - *dbg_redzone2(cachep, objp)); > - } > - *dbg_redzone1(cachep, objp) = RED_ACTIVE; > - *dbg_redzone2(cachep, objp) = RED_ACTIVE; > - } > - > - objp += obj_offset(cachep); > - if (cachep->ctor && cachep->flags & SLAB_POISON) > - cachep->ctor(objp); > - if ((unsigned long)objp & (arch_slab_minalign() - 1)) { > - pr_err("0x%px: not aligned to arch_slab_minalign()=%u\n", objp, > - arch_slab_minalign()); > - } > - return objp; > -} > -#else > -#define cache_alloc_debugcheck_after(a, b, objp, d) (objp) > -#endif > - > -static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - void *objp; > - struct array_cache *ac; > - > - check_irq_off(); > - > - ac = cpu_cache_get(cachep); > - if (likely(ac->avail)) { > - ac->touched = 1; > - objp = ac->entry[--ac->avail]; > - > - STATS_INC_ALLOCHIT(cachep); > - goto out; > - } > - > - STATS_INC_ALLOCMISS(cachep); > - objp = cache_alloc_refill(cachep, flags); > - /* > - * the 'ac' may be updated by cache_alloc_refill(), > - * and kmemleak_erase() requires its correct value. > - */ > - ac = cpu_cache_get(cachep); > - > -out: > - /* > - * To avoid a false negative, if an object that is in one of the > - * per-CPU caches is leaked, we need to make sure kmemleak doesn't > - * treat the array pointers as a reference to the object. > - */ > - if (objp) > - kmemleak_erase(&ac->entry[ac->avail]); > - return objp; > -} > - > -#ifdef CONFIG_NUMA > -static void *____cache_alloc_node(struct kmem_cache *, gfp_t, int); > - > -/* > - * Try allocating on another node if PFA_SPREAD_SLAB is a mempolicy is set. > - * > - * If we are in_interrupt, then process context, including cpusets and > - * mempolicy, may not apply and should not be used for allocation policy. > - */ > -static void *alternate_node_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - int nid_alloc, nid_here; > - > - if (in_interrupt() || (flags & __GFP_THISNODE)) > - return NULL; > - nid_alloc = nid_here = numa_mem_id(); > - if (cpuset_do_slab_mem_spread() && (cachep->flags & SLAB_MEM_SPREAD)) > - nid_alloc = cpuset_slab_spread_node(); > - else if (current->mempolicy) > - nid_alloc = mempolicy_slab_node(); > - if (nid_alloc != nid_here) > - return ____cache_alloc_node(cachep, flags, nid_alloc); > - return NULL; > -} > - > -/* > - * Fallback function if there was no memory available and no objects on a > - * certain node and fall back is permitted. First we scan all the > - * available node for available objects. If that fails then we > - * perform an allocation without specifying a node. This allows the page > - * allocator to do its reclaim / fallback magic. We then insert the > - * slab into the proper nodelist and then allocate from it. > - */ > -static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags) > -{ > - struct zonelist *zonelist; > - struct zoneref *z; > - struct zone *zone; > - enum zone_type highest_zoneidx = gfp_zone(flags); > - void *obj = NULL; > - struct slab *slab; > - int nid; > - unsigned int cpuset_mems_cookie; > - > - if (flags & __GFP_THISNODE) > - return NULL; > - > -retry_cpuset: > - cpuset_mems_cookie = read_mems_allowed_begin(); > - zonelist = node_zonelist(mempolicy_slab_node(), flags); > - > -retry: > - /* > - * Look through allowed nodes for objects available > - * from existing per node queues. > - */ > - for_each_zone_zonelist(zone, z, zonelist, highest_zoneidx) { > - nid = zone_to_nid(zone); > - > - if (cpuset_zone_allowed(zone, flags) && > - get_node(cache, nid) && > - get_node(cache, nid)->free_objects) { > - obj = ____cache_alloc_node(cache, > - gfp_exact_node(flags), nid); > - if (obj) > - break; > - } > - } > - > - if (!obj) { > - /* > - * This allocation will be performed within the constraints > - * of the current cpuset / memory policy requirements. > - * We may trigger various forms of reclaim on the allowed > - * set and go into memory reserves if necessary. > - */ > - slab = cache_grow_begin(cache, flags, numa_mem_id()); > - cache_grow_end(cache, slab); > - if (slab) { > - nid = slab_nid(slab); > - obj = ____cache_alloc_node(cache, > - gfp_exact_node(flags), nid); > - > - /* > - * Another processor may allocate the objects in > - * the slab since we are not holding any locks. > - */ > - if (!obj) > - goto retry; > - } > - } > - > - if (unlikely(!obj && read_mems_allowed_retry(cpuset_mems_cookie))) > - goto retry_cpuset; > - return obj; > -} > - > -/* > - * An interface to enable slab creation on nodeid > - */ > -static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, > - int nodeid) > -{ > - struct slab *slab; > - struct kmem_cache_node *n; > - void *obj = NULL; > - void *list = NULL; > - > - VM_BUG_ON(nodeid < 0 || nodeid >= MAX_NUMNODES); > - n = get_node(cachep, nodeid); > - BUG_ON(!n); > - > - check_irq_off(); > - raw_spin_lock(&n->list_lock); > - slab = get_first_slab(n, false); > - if (!slab) > - goto must_grow; > - > - check_spinlock_acquired_node(cachep, nodeid); > - > - STATS_INC_NODEALLOCS(cachep); > - STATS_INC_ACTIVE(cachep); > - STATS_SET_HIGH(cachep); > - > - BUG_ON(slab->active == cachep->num); > - > - obj = slab_get_obj(cachep, slab); > - n->free_objects--; > - > - fixup_slab_list(cachep, n, slab, &list); > - > - raw_spin_unlock(&n->list_lock); > - fixup_objfreelist_debug(cachep, &list); > - return obj; > - > -must_grow: > - raw_spin_unlock(&n->list_lock); > - slab = cache_grow_begin(cachep, gfp_exact_node(flags), nodeid); > - if (slab) { > - /* This slab isn't counted yet so don't update free_objects */ > - obj = slab_get_obj(cachep, slab); > - } > - cache_grow_end(cachep, slab); > - > - return obj ? obj : fallback_alloc(cachep, flags); > -} > - > -static __always_inline void * > -__do_cache_alloc(struct kmem_cache *cachep, gfp_t flags, int nodeid) > -{ > - void *objp = NULL; > - int slab_node = numa_mem_id(); > - > - if (nodeid == NUMA_NO_NODE) { > - if (current->mempolicy || cpuset_do_slab_mem_spread()) { > - objp = alternate_node_alloc(cachep, flags); > - if (objp) > - goto out; > - } > - /* > - * Use the locally cached objects if possible. > - * However ____cache_alloc does not allow fallback > - * to other nodes. It may fail while we still have > - * objects on other nodes available. > - */ > - objp = ____cache_alloc(cachep, flags); > - nodeid = slab_node; > - } else if (nodeid == slab_node) { > - objp = ____cache_alloc(cachep, flags); > - } else if (!get_node(cachep, nodeid)) { > - /* Node not bootstrapped yet */ > - objp = fallback_alloc(cachep, flags); > - goto out; > - } > - > - /* > - * We may just have run out of memory on the local node. > - * ____cache_alloc_node() knows how to locate memory on other nodes > - */ > - if (!objp) > - objp = ____cache_alloc_node(cachep, flags, nodeid); > -out: > - return objp; > -} > -#else > - > -static __always_inline void * > -__do_cache_alloc(struct kmem_cache *cachep, gfp_t flags, int nodeid __maybe_unused) > -{ > - return ____cache_alloc(cachep, flags); > -} > - > -#endif /* CONFIG_NUMA */ > - > -static __always_inline void * > -slab_alloc_node(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags, > - int nodeid, size_t orig_size, unsigned long caller) > -{ > - unsigned long save_flags; > - void *objp; > - struct obj_cgroup *objcg = NULL; > - bool init = false; > - > - flags &= gfp_allowed_mask; > - cachep = slab_pre_alloc_hook(cachep, lru, &objcg, 1, flags); > - if (unlikely(!cachep)) > - return NULL; > - > - objp = kfence_alloc(cachep, orig_size, flags); > - if (unlikely(objp)) > - goto out; > - > - local_irq_save(save_flags); > - objp = __do_cache_alloc(cachep, flags, nodeid); > - local_irq_restore(save_flags); > - objp = cache_alloc_debugcheck_after(cachep, flags, objp, caller); > - prefetchw(objp); > - init = slab_want_init_on_alloc(flags, cachep); > - > -out: > - slab_post_alloc_hook(cachep, objcg, flags, 1, &objp, init, > - cachep->object_size); > - return objp; > -} > - > -static __always_inline void * > -slab_alloc(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags, > - size_t orig_size, unsigned long caller) > -{ > - return slab_alloc_node(cachep, lru, flags, NUMA_NO_NODE, orig_size, > - caller); > -} > - > -/* > - * Caller needs to acquire correct kmem_cache_node's list_lock > - * @list: List of detached free slabs should be freed by caller > - */ > -static void free_block(struct kmem_cache *cachep, void **objpp, > - int nr_objects, int node, struct list_head *list) > -{ > - int i; > - struct kmem_cache_node *n = get_node(cachep, node); > - struct slab *slab; > - > - n->free_objects += nr_objects; > - > - for (i = 0; i < nr_objects; i++) { > - void *objp; > - struct slab *slab; > - > - objp = objpp[i]; > - > - slab = virt_to_slab(objp); > - list_del(&slab->slab_list); > - check_spinlock_acquired_node(cachep, node); > - slab_put_obj(cachep, slab, objp); > - STATS_DEC_ACTIVE(cachep); > - > - /* fixup slab chains */ > - if (slab->active == 0) { > - list_add(&slab->slab_list, &n->slabs_free); > - n->free_slabs++; > - } else { > - /* Unconditionally move a slab to the end of the > - * partial list on free - maximum time for the > - * other objects to be freed, too. > - */ > - list_add_tail(&slab->slab_list, &n->slabs_partial); > - } > - } > - > - while (n->free_objects > n->free_limit && !list_empty(&n->slabs_free)) { > - n->free_objects -= cachep->num; > - > - slab = list_last_entry(&n->slabs_free, struct slab, slab_list); > - list_move(&slab->slab_list, list); > - n->free_slabs--; > - n->total_slabs--; > - } > -} > - > -static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) > -{ > - int batchcount; > - struct kmem_cache_node *n; > - int node = numa_mem_id(); > - LIST_HEAD(list); > - > - batchcount = ac->batchcount; > - > - check_irq_off(); > - n = get_node(cachep, node); > - raw_spin_lock(&n->list_lock); > - if (n->shared) { > - struct array_cache *shared_array = n->shared; > - int max = shared_array->limit - shared_array->avail; > - if (max) { > - if (batchcount > max) > - batchcount = max; > - memcpy(&(shared_array->entry[shared_array->avail]), > - ac->entry, sizeof(void *) * batchcount); > - shared_array->avail += batchcount; > - goto free_done; > - } > - } > - > - free_block(cachep, ac->entry, batchcount, node, &list); > -free_done: > -#if STATS > - { > - int i = 0; > - struct slab *slab; > - > - list_for_each_entry(slab, &n->slabs_free, slab_list) { > - BUG_ON(slab->active); > - > - i++; > - } > - STATS_SET_FREEABLE(cachep, i); > - } > -#endif > - raw_spin_unlock(&n->list_lock); > - ac->avail -= batchcount; > - memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail); > - slabs_destroy(cachep, &list); > -} > - > -/* > - * Release an obj back to its cache. If the obj has a constructed state, it must > - * be in this state _before_ it is released. Called with disabled ints. > - */ > -static __always_inline void __cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - bool init; > - > - memcg_slab_free_hook(cachep, virt_to_slab(objp), &objp, 1); > - > - if (is_kfence_address(objp)) { > - kmemleak_free_recursive(objp, cachep->flags); > - __kfence_free(objp); > - return; > - } > - > - /* > - * As memory initialization might be integrated into KASAN, > - * kasan_slab_free and initialization memset must be > - * kept together to avoid discrepancies in behavior. > - */ > - init = slab_want_init_on_free(cachep); > - if (init && !kasan_has_integrated_init()) > - memset(objp, 0, cachep->object_size); > - /* KASAN might put objp into memory quarantine, delaying its reuse. */ > - if (kasan_slab_free(cachep, objp, init)) > - return; > - > - /* Use KCSAN to help debug racy use-after-free. */ > - if (!(cachep->flags & SLAB_TYPESAFE_BY_RCU)) > - __kcsan_check_access(objp, cachep->object_size, > - KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ASSERT); > - > - ___cache_free(cachep, objp, caller); > -} > - > -void ___cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - struct array_cache *ac = cpu_cache_get(cachep); > - > - check_irq_off(); > - kmemleak_free_recursive(objp, cachep->flags); > - objp = cache_free_debugcheck(cachep, objp, caller); > - > - /* > - * Skip calling cache_free_alien() when the platform is not numa. > - * This will avoid cache misses that happen while accessing slabp (which > - * is per page memory reference) to get nodeid. Instead use a global > - * variable to skip the call, which is mostly likely to be present in > - * the cache. > - */ > - if (nr_online_nodes > 1 && cache_free_alien(cachep, objp)) > - return; > - > - if (ac->avail < ac->limit) { > - STATS_INC_FREEHIT(cachep); > - } else { > - STATS_INC_FREEMISS(cachep); > - cache_flusharray(cachep, ac); > - } > - > - if (sk_memalloc_socks()) { > - struct slab *slab = virt_to_slab(objp); > - > - if (unlikely(slab_test_pfmemalloc(slab))) { > - cache_free_pfmemalloc(cachep, slab, objp); > - return; > - } > - } > - > - __free_one(ac, objp); > -} > - > -static __always_inline > -void *__kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, > - gfp_t flags) > -{ > - void *ret = slab_alloc(cachep, lru, flags, cachep->object_size, _RET_IP_); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, cachep, flags, NUMA_NO_NODE); > - > - return ret; > -} > - > -void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - return __kmem_cache_alloc_lru(cachep, NULL, flags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc); > - > -void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, > - gfp_t flags) > -{ > - return __kmem_cache_alloc_lru(cachep, lru, flags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_lru); > - > -static __always_inline void > -cache_alloc_debugcheck_after_bulk(struct kmem_cache *s, gfp_t flags, > - size_t size, void **p, unsigned long caller) > -{ > - size_t i; > - > - for (i = 0; i < size; i++) > - p[i] = cache_alloc_debugcheck_after(s, flags, p[i], caller); > -} > - > -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, > - void **p) > -{ > - struct obj_cgroup *objcg = NULL; > - unsigned long irqflags; > - size_t i; > - > - s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); > - if (!s) > - return 0; > - > - local_irq_save(irqflags); > - for (i = 0; i < size; i++) { > - void *objp = kfence_alloc(s, s->object_size, flags) ?: > - __do_cache_alloc(s, flags, NUMA_NO_NODE); > - > - if (unlikely(!objp)) > - goto error; > - p[i] = objp; > - } > - local_irq_restore(irqflags); > - > - cache_alloc_debugcheck_after_bulk(s, flags, size, p, _RET_IP_); > - > - /* > - * memcg and kmem_cache debug support and memory initialization. > - * Done outside of the IRQ disabled section. > - */ > - slab_post_alloc_hook(s, objcg, flags, size, p, > - slab_want_init_on_alloc(flags, s), s->object_size); > - /* FIXME: Trace call missing. Christoph would like a bulk variant */ > - return size; > -error: > - local_irq_restore(irqflags); > - cache_alloc_debugcheck_after_bulk(s, flags, i, p, _RET_IP_); > - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); > - kmem_cache_free_bulk(s, i, p); > - return 0; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_bulk); > - > -/** > - * kmem_cache_alloc_node - Allocate an object on the specified node > - * @cachep: The cache to allocate from. > - * @flags: See kmalloc(). > - * @nodeid: node number of the target node. > - * > - * Identical to kmem_cache_alloc but it will allocate memory on the given > - * node, which can improve the performance for cpu bound structures. > - * > - * Fallback to other node is possible if __GFP_THISNODE is not set. > - * > - * Return: pointer to the new object or %NULL in case of error > - */ > -void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) > -{ > - void *ret = slab_alloc_node(cachep, NULL, flags, nodeid, cachep->object_size, _RET_IP_); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, cachep, flags, nodeid); > - > - return ret; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_node); > - > -void *__kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, > - int nodeid, size_t orig_size, > - unsigned long caller) > -{ > - return slab_alloc_node(cachep, NULL, flags, nodeid, > - orig_size, caller); > -} > - > -#ifdef CONFIG_PRINTK > -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) > -{ > - struct kmem_cache *cachep; > - unsigned int objnr; > - void *objp; > - > - kpp->kp_ptr = object; > - kpp->kp_slab = slab; > - cachep = slab->slab_cache; > - kpp->kp_slab_cache = cachep; > - objp = object - obj_offset(cachep); > - kpp->kp_data_offset = obj_offset(cachep); > - slab = virt_to_slab(objp); > - objnr = obj_to_index(cachep, slab, objp); > - objp = index_to_obj(cachep, slab, objnr); > - kpp->kp_objp = objp; > - if (DEBUG && cachep->flags & SLAB_STORE_USER) > - kpp->kp_ret = *dbg_userword(cachep, objp); > -} > -#endif > - > -static __always_inline > -void __do_kmem_cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - unsigned long flags; > - > - local_irq_save(flags); > - debug_check_no_locks_freed(objp, cachep->object_size); > - if (!(cachep->flags & SLAB_DEBUG_OBJECTS)) > - debug_check_no_obj_freed(objp, cachep->object_size); > - __cache_free(cachep, objp, caller); > - local_irq_restore(flags); > -} > - > -void __kmem_cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - __do_kmem_cache_free(cachep, objp, caller); > -} > - > -/** > - * kmem_cache_free - Deallocate an object > - * @cachep: The cache the allocation was from. > - * @objp: The previously allocated object. > - * > - * Free an object which was previously allocated from this > - * cache. > - */ > -void kmem_cache_free(struct kmem_cache *cachep, void *objp) > -{ > - cachep = cache_from_obj(cachep, objp); > - if (!cachep) > - return; > - > - trace_kmem_cache_free(_RET_IP_, objp, cachep); > - __do_kmem_cache_free(cachep, objp, _RET_IP_); > -} > -EXPORT_SYMBOL(kmem_cache_free); > - > -void kmem_cache_free_bulk(struct kmem_cache *orig_s, size_t size, void **p) > -{ > - unsigned long flags; > - > - local_irq_save(flags); > - for (int i = 0; i < size; i++) { > - void *objp = p[i]; > - struct kmem_cache *s; > - > - if (!orig_s) { > - struct folio *folio = virt_to_folio(objp); > - > - /* called via kfree_bulk */ > - if (!folio_test_slab(folio)) { > - local_irq_restore(flags); > - free_large_kmalloc(folio, objp); > - local_irq_save(flags); > - continue; > - } > - s = folio_slab(folio)->slab_cache; > - } else { > - s = cache_from_obj(orig_s, objp); > - } > - > - if (!s) > - continue; > - > - debug_check_no_locks_freed(objp, s->object_size); > - if (!(s->flags & SLAB_DEBUG_OBJECTS)) > - debug_check_no_obj_freed(objp, s->object_size); > - > - __cache_free(s, objp, _RET_IP_); > - } > - local_irq_restore(flags); > - > - /* FIXME: add tracing */ > -} > -EXPORT_SYMBOL(kmem_cache_free_bulk); > - > -/* > - * This initializes kmem_cache_node or resizes various caches for all nodes. > - */ > -static int setup_kmem_cache_nodes(struct kmem_cache *cachep, gfp_t gfp) > -{ > - int ret; > - int node; > - struct kmem_cache_node *n; > - > - for_each_online_node(node) { > - ret = setup_kmem_cache_node(cachep, node, gfp, true); > - if (ret) > - goto fail; > - > - } > - > - return 0; > - > -fail: > - if (!cachep->list.next) { > - /* Cache is not active yet. Roll back what we did */ > - node--; > - while (node >= 0) { > - n = get_node(cachep, node); > - if (n) { > - kfree(n->shared); > - free_alien_cache(n->alien); > - kfree(n); > - cachep->node[node] = NULL; > - } > - node--; > - } > - } > - return -ENOMEM; > -} > - > -/* Always called with the slab_mutex held */ > -static int do_tune_cpucache(struct kmem_cache *cachep, int limit, > - int batchcount, int shared, gfp_t gfp) > -{ > - struct array_cache __percpu *cpu_cache, *prev; > - int cpu; > - > - cpu_cache = alloc_kmem_cache_cpus(cachep, limit, batchcount); > - if (!cpu_cache) > - return -ENOMEM; > - > - prev = cachep->cpu_cache; > - cachep->cpu_cache = cpu_cache; > - /* > - * Without a previous cpu_cache there's no need to synchronize remote > - * cpus, so skip the IPIs. > - */ > - if (prev) > - kick_all_cpus_sync(); > - > - check_irq_on(); > - cachep->batchcount = batchcount; > - cachep->limit = limit; > - cachep->shared = shared; > - > - if (!prev) > - goto setup_node; > - > - for_each_online_cpu(cpu) { > - LIST_HEAD(list); > - int node; > - struct kmem_cache_node *n; > - struct array_cache *ac = per_cpu_ptr(prev, cpu); > - > - node = cpu_to_mem(cpu); > - n = get_node(cachep, node); > - raw_spin_lock_irq(&n->list_lock); > - free_block(cachep, ac->entry, ac->avail, node, &list); > - raw_spin_unlock_irq(&n->list_lock); > - slabs_destroy(cachep, &list); > - } > - free_percpu(prev); > - > -setup_node: > - return setup_kmem_cache_nodes(cachep, gfp); > -} > - > -/* Called with slab_mutex held always */ > -static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp) > -{ > - int err; > - int limit = 0; > - int shared = 0; > - int batchcount = 0; > - > - err = cache_random_seq_create(cachep, cachep->num, gfp); > - if (err) > - goto end; > - > - /* > - * The head array serves three purposes: > - * - create a LIFO ordering, i.e. return objects that are cache-warm > - * - reduce the number of spinlock operations. > - * - reduce the number of linked list operations on the slab and > - * bufctl chains: array operations are cheaper. > - * The numbers are guessed, we should auto-tune as described by > - * Bonwick. > - */ > - if (cachep->size > 131072) > - limit = 1; > - else if (cachep->size > PAGE_SIZE) > - limit = 8; > - else if (cachep->size > 1024) > - limit = 24; > - else if (cachep->size > 256) > - limit = 54; > - else > - limit = 120; > - > - /* > - * CPU bound tasks (e.g. network routing) can exhibit cpu bound > - * allocation behaviour: Most allocs on one cpu, most free operations > - * on another cpu. For these cases, an efficient object passing between > - * cpus is necessary. This is provided by a shared array. The array > - * replaces Bonwick's magazine layer. > - * On uniprocessor, it's functionally equivalent (but less efficient) > - * to a larger limit. Thus disabled by default. > - */ > - shared = 0; > - if (cachep->size <= PAGE_SIZE && num_possible_cpus() > 1) > - shared = 8; > - > -#if DEBUG > - /* > - * With debugging enabled, large batchcount lead to excessively long > - * periods with disabled local interrupts. Limit the batchcount > - */ > - if (limit > 32) > - limit = 32; > -#endif > - batchcount = (limit + 1) / 2; > - err = do_tune_cpucache(cachep, limit, batchcount, shared, gfp); > -end: > - if (err) > - pr_err("enable_cpucache failed for %s, error %d\n", > - cachep->name, -err); > - return err; > -} > - > -/* > - * Drain an array if it contains any elements taking the node lock only if > - * necessary. Note that the node listlock also protects the array_cache > - * if drain_array() is used on the shared array. > - */ > -static void drain_array(struct kmem_cache *cachep, struct kmem_cache_node *n, > - struct array_cache *ac, int node) > -{ > - LIST_HEAD(list); > - > - /* ac from n->shared can be freed if we don't hold the slab_mutex. */ > - check_mutex_acquired(); > - > - if (!ac || !ac->avail) > - return; > - > - if (ac->touched) { > - ac->touched = 0; > - return; > - } > - > - raw_spin_lock_irq(&n->list_lock); > - drain_array_locked(cachep, ac, node, false, &list); > - raw_spin_unlock_irq(&n->list_lock); > - > - slabs_destroy(cachep, &list); > -} > - > -/** > - * cache_reap - Reclaim memory from caches. > - * @w: work descriptor > - * > - * Called from workqueue/eventd every few seconds. > - * Purpose: > - * - clear the per-cpu caches for this CPU. > - * - return freeable pages to the main free memory pool. > - * > - * If we cannot acquire the cache chain mutex then just give up - we'll try > - * again on the next iteration. > - */ > -static void cache_reap(struct work_struct *w) > -{ > - struct kmem_cache *searchp; > - struct kmem_cache_node *n; > - int node = numa_mem_id(); > - struct delayed_work *work = to_delayed_work(w); > - > - if (!mutex_trylock(&slab_mutex)) > - /* Give up. Setup the next iteration. */ > - goto out; > - > - list_for_each_entry(searchp, &slab_caches, list) { > - check_irq_on(); > - > - /* > - * We only take the node lock if absolutely necessary and we > - * have established with reasonable certainty that > - * we can do some work if the lock was obtained. > - */ > - n = get_node(searchp, node); > - > - reap_alien(searchp, n); > - > - drain_array(searchp, n, cpu_cache_get(searchp), node); > - > - /* > - * These are racy checks but it does not matter > - * if we skip one check or scan twice. > - */ > - if (time_after(n->next_reap, jiffies)) > - goto next; > - > - n->next_reap = jiffies + REAPTIMEOUT_NODE; > - > - drain_array(searchp, n, n->shared, node); > - > - if (n->free_touched) > - n->free_touched = 0; > - else { > - int freed; > - > - freed = drain_freelist(searchp, n, (n->free_limit + > - 5 * searchp->num - 1) / (5 * searchp->num)); > - STATS_ADD_REAPED(searchp, freed); > - } > -next: > - cond_resched(); > - } > - check_irq_on(); > - mutex_unlock(&slab_mutex); > - next_reap_node(); > -out: > - /* Set up the next iteration */ > - schedule_delayed_work_on(smp_processor_id(), work, > - round_jiffies_relative(REAPTIMEOUT_AC)); > -} > - > -void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo) > -{ > - unsigned long active_objs, num_objs, active_slabs; > - unsigned long total_slabs = 0, free_objs = 0, shared_avail = 0; > - unsigned long free_slabs = 0; > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(cachep, node, n) { > - check_irq_on(); > - raw_spin_lock_irq(&n->list_lock); > - > - total_slabs += n->total_slabs; > - free_slabs += n->free_slabs; > - free_objs += n->free_objects; > - > - if (n->shared) > - shared_avail += n->shared->avail; > - > - raw_spin_unlock_irq(&n->list_lock); > - } > - num_objs = total_slabs * cachep->num; > - active_slabs = total_slabs - free_slabs; > - active_objs = num_objs - free_objs; > - > - sinfo->active_objs = active_objs; > - sinfo->num_objs = num_objs; > - sinfo->active_slabs = active_slabs; > - sinfo->num_slabs = total_slabs; > - sinfo->shared_avail = shared_avail; > - sinfo->limit = cachep->limit; > - sinfo->batchcount = cachep->batchcount; > - sinfo->shared = cachep->shared; > - sinfo->objects_per_slab = cachep->num; > - sinfo->cache_order = cachep->gfporder; > -} > - > -void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *cachep) > -{ > -#if STATS > - { /* node stats */ > - unsigned long high = cachep->high_mark; > - unsigned long allocs = cachep->num_allocations; > - unsigned long grown = cachep->grown; > - unsigned long reaped = cachep->reaped; > - unsigned long errors = cachep->errors; > - unsigned long max_freeable = cachep->max_freeable; > - unsigned long node_allocs = cachep->node_allocs; > - unsigned long node_frees = cachep->node_frees; > - unsigned long overflows = cachep->node_overflow; > - > - seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu %4lu %4lu %4lu %4lu %4lu", > - allocs, high, grown, > - reaped, errors, max_freeable, node_allocs, > - node_frees, overflows); > - } > - /* cpu stats */ > - { > - unsigned long allochit = atomic_read(&cachep->allochit); > - unsigned long allocmiss = atomic_read(&cachep->allocmiss); > - unsigned long freehit = atomic_read(&cachep->freehit); > - unsigned long freemiss = atomic_read(&cachep->freemiss); > - > - seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu", > - allochit, allocmiss, freehit, freemiss); > - } > -#endif > -} > - > -#define MAX_SLABINFO_WRITE 128 > -/** > - * slabinfo_write - Tuning for the slab allocator > - * @file: unused > - * @buffer: user buffer > - * @count: data length > - * @ppos: unused > - * > - * Return: %0 on success, negative error code otherwise. > - */ > -ssize_t slabinfo_write(struct file *file, const char __user *buffer, > - size_t count, loff_t *ppos) > -{ > - char kbuf[MAX_SLABINFO_WRITE + 1], *tmp; > - int limit, batchcount, shared, res; > - struct kmem_cache *cachep; > - > - if (count > MAX_SLABINFO_WRITE) > - return -EINVAL; > - if (copy_from_user(&kbuf, buffer, count)) > - return -EFAULT; > - kbuf[MAX_SLABINFO_WRITE] = '\0'; > - > - tmp = strchr(kbuf, ' '); > - if (!tmp) > - return -EINVAL; > - *tmp = '\0'; > - tmp++; > - if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3) > - return -EINVAL; > - > - /* Find the cache in the chain of caches. */ > - mutex_lock(&slab_mutex); > - res = -EINVAL; > - list_for_each_entry(cachep, &slab_caches, list) { > - if (!strcmp(cachep->name, kbuf)) { > - if (limit < 1 || batchcount < 1 || > - batchcount > limit || shared < 0) { > - res = 0; > - } else { > - res = do_tune_cpucache(cachep, limit, > - batchcount, shared, > - GFP_KERNEL); > - } > - break; > - } > - } > - mutex_unlock(&slab_mutex); > - if (res >= 0) > - res = count; > - return res; > -} > - > -#ifdef CONFIG_HARDENED_USERCOPY > -/* > - * Rejects incorrectly sized objects and objects that are to be copied > - * to/from userspace but do not fall entirely within the containing slab > - * cache's usercopy region. > - * > - * Returns NULL if check passes, otherwise const char * to name of cache > - * to indicate an error. > - */ > -void __check_heap_object(const void *ptr, unsigned long n, > - const struct slab *slab, bool to_user) > -{ > - struct kmem_cache *cachep; > - unsigned int objnr; > - unsigned long offset; > - > - ptr = kasan_reset_tag(ptr); > - > - /* Find and validate object. */ > - cachep = slab->slab_cache; > - objnr = obj_to_index(cachep, slab, (void *)ptr); > - BUG_ON(objnr >= cachep->num); > - > - /* Find offset within object. */ > - if (is_kfence_address(ptr)) > - offset = ptr - kfence_object_start(ptr); > - else > - offset = ptr - index_to_obj(cachep, slab, objnr) - obj_offset(cachep); > - > - /* Allow address range falling entirely within usercopy region. */ > - if (offset >= cachep->useroffset && > - offset - cachep->useroffset <= cachep->usersize && > - n <= cachep->useroffset - offset + cachep->usersize) > - return; > - > - usercopy_abort("SLAB object", cachep->name, to_user, offset, n); > -} > -#endif /* CONFIG_HARDENED_USERCOPY */ > diff --git a/mm/slab.h b/mm/slab.h > index 43966aa5fadf..53e97b7640e9 100644 > --- a/mm/slab.h > +++ b/mm/slab.h > @@ -9,60 +9,12 @@ > struct slab { > unsigned long __page_flags; > > -#if defined(CONFIG_SLAB) > - > - struct kmem_cache *slab_cache; > - union { > - struct { > - struct list_head slab_list; > - void *freelist; /* array of free object indexes */ > - void *s_mem; /* first object */ > - }; > - struct rcu_head rcu_head; > - }; > - unsigned int active; > - > -#elif defined(CONFIG_SLUB) > - > - struct kmem_cache *slab_cache; > - union { > - struct { > - union { > - struct list_head slab_list; > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - struct { > - struct slab *next; > - int slabs; /* Nr of slabs left */ > - }; > -#endif > - }; > - /* Double-word boundary */ > - void *freelist; /* first free object */ > - union { > - unsigned long counters; > - struct { > - unsigned inuse:16; > - unsigned objects:15; > - unsigned frozen:1; > - }; > - }; > - }; > - struct rcu_head rcu_head; > - }; > - unsigned int __unused; > - > -#elif defined(CONFIG_SLOB) > - > struct list_head slab_list; > void *__unused_1; > void *freelist; /* first free block */ > long units; > unsigned int __unused_2; > > -#else > -#error "Unexpected slab allocator configured" > -#endif > - > atomic_t __page_refcount; > #ifdef CONFIG_MEMCG > unsigned long memcg_data; > @@ -72,20 +24,13 @@ struct slab { > #define SLAB_MATCH(pg, sl) \ > static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl)) > SLAB_MATCH(flags, __page_flags); > -#ifndef CONFIG_SLOB > -SLAB_MATCH(compound_head, slab_cache); /* Ensure bit 0 is clear */ > -#else > SLAB_MATCH(compound_head, slab_list); /* Ensure bit 0 is clear */ > -#endif > SLAB_MATCH(_refcount, __page_refcount); > #ifdef CONFIG_MEMCG > SLAB_MATCH(memcg_data, memcg_data); > #endif > #undef SLAB_MATCH > static_assert(sizeof(struct slab) <= sizeof(struct page)); > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && defined(CONFIG_SLUB) > -static_assert(IS_ALIGNED(offsetof(struct slab, freelist), 2*sizeof(void *))); > -#endif > > /** > * folio_slab - Converts from folio to slab. > @@ -200,7 +145,6 @@ static inline size_t slab_size(const struct slab *slab) > return PAGE_SIZE << slab_order(slab); > } > > -#ifdef CONFIG_SLOB > /* > * Common fields provided in kmem_cache by all slab allocators > * This struct is either used directly by the allocator (SLOB) > @@ -223,16 +167,6 @@ struct kmem_cache { > struct list_head list; /* List of all slab caches on the system */ > }; > > -#endif /* CONFIG_SLOB */ > - > -#ifdef CONFIG_SLAB > -#include <linux/slab_def.h> > -#endif > - > -#ifdef CONFIG_SLUB > -#include <linux/slub_def.h> > -#endif > - > #include <linux/memcontrol.h> > #include <linux/fault-inject.h> > #include <linux/kasan.h> > @@ -268,26 +202,6 @@ extern struct list_head slab_caches; > /* The slab cache that manages slab cache information */ > extern struct kmem_cache *kmem_cache; > > -/* A table of kmalloc cache names and sizes */ > -extern const struct kmalloc_info_struct { > - const char *name[NR_KMALLOC_TYPES]; > - unsigned int size; > -} kmalloc_info[]; > - > -#ifndef CONFIG_SLOB > -/* Kmalloc array related functions */ > -void setup_kmalloc_cache_index_table(void); > -void create_kmalloc_caches(slab_flags_t); > - > -/* Find the kmalloc slab corresponding for a certain size */ > -struct kmem_cache *kmalloc_slab(size_t, gfp_t); > - > -void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, > - int node, size_t orig_size, > - unsigned long caller); > -void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller); > -#endif > - > gfp_t kmalloc_fix_flags(gfp_t flags); > > /* Functions provided by the slab allocators */ > @@ -303,14 +217,6 @@ extern void create_boot_cache(struct kmem_cache *, const char *name, > int slab_unmergeable(struct kmem_cache *s); > struct kmem_cache *find_mergeable(unsigned size, unsigned align, > slab_flags_t flags, const char *name, void (*ctor)(void *)); > -#ifndef CONFIG_SLOB > -struct kmem_cache * > -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > - slab_flags_t flags, void (*ctor)(void *)); > - > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name); > -#else > static inline struct kmem_cache * > __kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > slab_flags_t flags, void (*ctor)(void *)) > @@ -321,15 +227,10 @@ static inline slab_flags_t kmem_cache_flags(unsigned int object_size, > { > return flags; > } > -#endif > > static inline bool is_kmalloc_cache(struct kmem_cache *s) > { > -#ifndef CONFIG_SLOB > - return (s->flags & SLAB_KMALLOC); > -#else > return false; > -#endif > } > > /* Legal flag mask for kmem_cache_create(), for various configurations */ > @@ -337,26 +238,9 @@ static inline bool is_kmalloc_cache(struct kmem_cache *s) > SLAB_CACHE_DMA32 | SLAB_PANIC | \ > SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS ) > > -#if defined(CONFIG_DEBUG_SLAB) > -#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) > -#elif defined(CONFIG_SLUB_DEBUG) > -#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ > - SLAB_TRACE | SLAB_CONSISTENCY_CHECKS) > -#else > #define SLAB_DEBUG_FLAGS (0) > -#endif > > -#if defined(CONFIG_SLAB) > -#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \ > - SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \ > - SLAB_ACCOUNT) > -#elif defined(CONFIG_SLUB) > -#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ > - SLAB_TEMPORARY | SLAB_ACCOUNT | \ > - SLAB_NO_USER_FLAGS | SLAB_KMALLOC) > -#else > #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE) > -#endif > > /* Common flags available with current configuration */ > #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS) > @@ -409,19 +293,6 @@ static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s) > NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B; > } > > -#ifdef CONFIG_SLUB_DEBUG > -#ifdef CONFIG_SLUB_DEBUG_ON > -DECLARE_STATIC_KEY_TRUE(slub_debug_enabled); > -#else > -DECLARE_STATIC_KEY_FALSE(slub_debug_enabled); > -#endif > -extern void print_tracking(struct kmem_cache *s, void *object); > -long validate_slab_cache(struct kmem_cache *s); > -static inline bool __slub_debug_enabled(void) > -{ > - return static_branch_unlikely(&slub_debug_enabled); > -} > -#else > static inline void print_tracking(struct kmem_cache *s, void *object) > { > } > @@ -429,7 +300,6 @@ static inline bool __slub_debug_enabled(void) > { > return false; > } > -#endif > > /* > * Returns true if any of the specified slub_debug flags is enabled for the > @@ -438,160 +308,9 @@ static inline bool __slub_debug_enabled(void) > */ > static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags) > { > - if (IS_ENABLED(CONFIG_SLUB_DEBUG)) > - VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS)); > - if (__slub_debug_enabled()) > - return s->flags & flags; > return false; > } > > -#ifdef CONFIG_MEMCG_KMEM > -/* > - * slab_objcgs - get the object cgroups vector associated with a slab > - * @slab: a pointer to the slab struct > - * > - * Returns a pointer to the object cgroups vector associated with the slab, > - * or NULL if no such vector has been associated yet. > - */ > -static inline struct obj_cgroup **slab_objcgs(struct slab *slab) > -{ > - unsigned long memcg_data = READ_ONCE(slab->memcg_data); > - > - VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), > - slab_page(slab)); > - VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, slab_page(slab)); > - > - return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); > -} > - > -int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s, > - gfp_t gfp, bool new_slab); > -void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, > - enum node_stat_item idx, int nr); > - > -static inline void memcg_free_slab_cgroups(struct slab *slab) > -{ > - kfree(slab_objcgs(slab)); > - slab->memcg_data = 0; > -} > - > -static inline size_t obj_full_size(struct kmem_cache *s) > -{ > - /* > - * For each accounted object there is an extra space which is used > - * to store obj_cgroup membership. Charge it too. > - */ > - return s->size + sizeof(struct obj_cgroup *); > -} > - > -/* > - * Returns false if the allocation should fail. > - */ > -static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, > - struct list_lru *lru, > - struct obj_cgroup **objcgp, > - size_t objects, gfp_t flags) > -{ > - struct obj_cgroup *objcg; > - > - if (!memcg_kmem_online()) > - return true; > - > - if (!(flags & __GFP_ACCOUNT) && !(s->flags & SLAB_ACCOUNT)) > - return true; > - > - objcg = get_obj_cgroup_from_current(); > - if (!objcg) > - return true; > - > - if (lru) { > - int ret; > - struct mem_cgroup *memcg; > - > - memcg = get_mem_cgroup_from_objcg(objcg); > - ret = memcg_list_lru_alloc(memcg, lru, flags); > - css_put(&memcg->css); > - > - if (ret) > - goto out; > - } > - > - if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s))) > - goto out; > - > - *objcgp = objcg; > - return true; > -out: > - obj_cgroup_put(objcg); > - return false; > -} > - > -static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, > - struct obj_cgroup *objcg, > - gfp_t flags, size_t size, > - void **p) > -{ > - struct slab *slab; > - unsigned long off; > - size_t i; > - > - if (!memcg_kmem_online() || !objcg) > - return; > - > - for (i = 0; i < size; i++) { > - if (likely(p[i])) { > - slab = virt_to_slab(p[i]); > - > - if (!slab_objcgs(slab) && > - memcg_alloc_slab_cgroups(slab, s, flags, > - false)) { > - obj_cgroup_uncharge(objcg, obj_full_size(s)); > - continue; > - } > - > - off = obj_to_index(s, slab, p[i]); > - obj_cgroup_get(objcg); > - slab_objcgs(slab)[off] = objcg; > - mod_objcg_state(objcg, slab_pgdat(slab), > - cache_vmstat_idx(s), obj_full_size(s)); > - } else { > - obj_cgroup_uncharge(objcg, obj_full_size(s)); > - } > - } > - obj_cgroup_put(objcg); > -} > - > -static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, > - void **p, int objects) > -{ > - struct obj_cgroup **objcgs; > - int i; > - > - if (!memcg_kmem_online()) > - return; > - > - objcgs = slab_objcgs(slab); > - if (!objcgs) > - return; > - > - for (i = 0; i < objects; i++) { > - struct obj_cgroup *objcg; > - unsigned int off; > - > - off = obj_to_index(s, slab, p[i]); > - objcg = objcgs[off]; > - if (!objcg) > - continue; > - > - objcgs[off] = NULL; > - obj_cgroup_uncharge(objcg, obj_full_size(s)); > - mod_objcg_state(objcg, slab_pgdat(slab), cache_vmstat_idx(s), > - -obj_full_size(s)); > - obj_cgroup_put(objcg); > - } > -} > - > -#else /* CONFIG_MEMCG_KMEM */ > static inline struct obj_cgroup **slab_objcgs(struct slab *slab) > { > return NULL; > @@ -632,90 +351,12 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, > void **p, int objects) > { > } > -#endif /* CONFIG_MEMCG_KMEM */ > - > -#ifndef CONFIG_SLOB > -static inline struct kmem_cache *virt_to_cache(const void *obj) > -{ > - struct slab *slab; > - > - slab = virt_to_slab(obj); > - if (WARN_ONCE(!slab, "%s: Object is not a Slab page!\n", > - __func__)) > - return NULL; > - return slab->slab_cache; > -} > - > -static __always_inline void account_slab(struct slab *slab, int order, > - struct kmem_cache *s, gfp_t gfp) > -{ > - if (memcg_kmem_online() && (s->flags & SLAB_ACCOUNT)) > - memcg_alloc_slab_cgroups(slab, s, gfp, true); > - > - mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), > - PAGE_SIZE << order); > -} > - > -static __always_inline void unaccount_slab(struct slab *slab, int order, > - struct kmem_cache *s) > -{ > - if (memcg_kmem_online()) > - memcg_free_slab_cgroups(slab); > - > - mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), > - -(PAGE_SIZE << order)); > -} > - > -static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) > -{ > - struct kmem_cache *cachep; > - > - if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && > - !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) > - return s; > - > - cachep = virt_to_cache(x); > - if (WARN(cachep && cachep != s, > - "%s: Wrong slab cache. %s but object is from %s\n", > - __func__, s->name, cachep->name)) > - print_tracking(cachep, x); > - return cachep; > -} > - > -void free_large_kmalloc(struct folio *folio, void *object); > - > -#endif /* CONFIG_SLOB */ > > size_t __ksize(const void *objp); > > static inline size_t slab_ksize(const struct kmem_cache *s) > { > -#ifndef CONFIG_SLUB > return s->object_size; > - > -#else /* CONFIG_SLUB */ > -# ifdef CONFIG_SLUB_DEBUG > - /* > - * Debugging requires use of the padding between object > - * and whatever may come after it. > - */ > - if (s->flags & (SLAB_RED_ZONE | SLAB_POISON)) > - return s->object_size; > -# endif > - if (s->flags & SLAB_KASAN) > - return s->object_size; > - /* > - * If we have the need to store the freelist pointer > - * back there or track user information then we can > - * only use the space before that information. > - */ > - if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER)) > - return s->inuse; > - /* > - * Else we can use all the padding etc for the allocation > - */ > - return s->size; > -#endif > } > > static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, > @@ -777,77 +418,18 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, > memcg_slab_post_alloc_hook(s, objcg, flags, size, p); > } > > -#ifndef CONFIG_SLOB > -/* > - * The slab lists for all objects. > - */ > -struct kmem_cache_node { > -#ifdef CONFIG_SLAB > - raw_spinlock_t list_lock; > - struct list_head slabs_partial; /* partial list first, better asm code */ > - struct list_head slabs_full; > - struct list_head slabs_free; > - unsigned long total_slabs; /* length of all slab lists */ > - unsigned long free_slabs; /* length of free slab list only */ > - unsigned long free_objects; > - unsigned int free_limit; > - unsigned int colour_next; /* Per-node cache coloring */ > - struct array_cache *shared; /* shared per node */ > - struct alien_cache **alien; /* on other nodes */ > - unsigned long next_reap; /* updated without locking */ > - int free_touched; /* updated without locking */ > -#endif > - > -#ifdef CONFIG_SLUB > - spinlock_t list_lock; > - unsigned long nr_partial; > - struct list_head partial; > -#ifdef CONFIG_SLUB_DEBUG > - atomic_long_t nr_slabs; > - atomic_long_t total_objects; > - struct list_head full; > -#endif > -#endif > - > -}; > - > -static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node) > -{ > - return s->node[node]; > -} > - > -/* > - * Iterator over all nodes. The body will be executed for each node that has > - * a kmem_cache_node structure allocated (which is true for all online nodes) > - */ > -#define for_each_kmem_cache_node(__s, __node, __n) \ > - for (__node = 0; __node < nr_node_ids; __node++) \ > - if ((__n = get_node(__s, __node))) > - > -#endif > - > -#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG) > -void dump_unreclaimable_slab(void); > -#else > static inline void dump_unreclaimable_slab(void) > { > } > -#endif > > void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr); > > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, > - gfp_t gfp); > -void cache_random_seq_destroy(struct kmem_cache *cachep); > -#else > static inline int cache_random_seq_create(struct kmem_cache *cachep, > unsigned int count, gfp_t gfp) > { > return 0; > } > static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { } > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > > static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c) > { > @@ -871,11 +453,7 @@ static inline bool slab_want_init_on_free(struct kmem_cache *c) > return false; > } > > -#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) > -void debugfs_slab_release(struct kmem_cache *); > -#else > static inline void debugfs_slab_release(struct kmem_cache *s) { } > -#endif > > #ifdef CONFIG_PRINTK > #define KS_ADDRS_COUNT 16 > @@ -903,8 +481,4 @@ void __check_heap_object(const void *ptr, unsigned long n, > } > #endif > > -#ifdef CONFIG_SLUB_DEBUG > -void skip_orig_size_check(struct kmem_cache *s, const void *object); > -#endif > - > #endif /* MM_SLAB_H */ > diff --git a/mm/slab_common.c b/mm/slab_common.c > index bf4e777cfe90..5f6a59e31abd 100644 > --- a/mm/slab_common.c > +++ b/mm/slab_common.c > @@ -69,11 +69,6 @@ static int __init setup_slab_merge(char *str) > return 1; > } > > -#ifdef CONFIG_SLUB > -__setup_param("slub_nomerge", slub_nomerge, setup_slab_nomerge, 0); > -__setup_param("slub_merge", slub_merge, setup_slab_merge, 0); > -#endif > - > __setup("slab_nomerge", setup_slab_nomerge); > __setup("slab_merge", setup_slab_merge); > > @@ -195,15 +190,29 @@ struct kmem_cache *find_mergeable(unsigned int size, unsigned int align, > if (s->size - size >= sizeof(void *)) > continue; > > - if (IS_ENABLED(CONFIG_SLAB) && align && > - (align > s->align || s->align % align)) > - continue; > - > return s; > } > return NULL; > } > > +struct slab_rcu { > + struct rcu_head head; > + int size; > +}; > + > +int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags) > +{ > + if (flags & SLAB_TYPESAFE_BY_RCU) { > + /* leave room for rcu footer at the end of object */ > + c->size += sizeof(struct slab_rcu); > + } > + > + /* Actual size allocated */ > + c->size = PAGE_SIZE << get_order(c->size); > + c->flags = flags; > + return 0; > +} > + > static struct kmem_cache *create_cache(const char *name, > unsigned int object_size, unsigned int align, > slab_flags_t flags, unsigned int useroffset, > @@ -285,20 +294,6 @@ kmem_cache_create_usercopy(const char *name, > const char *cache_name; > int err; > > -#ifdef CONFIG_SLUB_DEBUG > - /* > - * If no slub_debug was enabled globally, the static key is not yet > - * enabled by setup_slub_debug(). Enable it if the cache is being > - * created with any of the debugging flags passed explicitly. > - * It's also possible that this is the first cache created with > - * SLAB_STORE_USER and we should init stack_depot for it. > - */ > - if (flags & SLAB_DEBUG_FLAGS) > - static_branch_enable(&slub_debug_enabled); > - if (flags & SLAB_STORE_USER) > - stack_depot_init(); > -#endif > - > mutex_lock(&slab_mutex); > > err = kmem_cache_sanity_check(name, size); > @@ -552,7 +547,8 @@ static void kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab * > { > if (__kfence_obj_info(kpp, object, slab)) > return; > - __kmem_obj_info(kpp, object, slab); > + kpp->kp_ptr = object; > + kpp->kp_slab = slab; > } > > /** > @@ -625,462 +621,6 @@ void kmem_dump_obj(void *object) > EXPORT_SYMBOL_GPL(kmem_dump_obj); > #endif > > -#ifndef CONFIG_SLOB > -/* Create a cache during boot when no slab services are available yet */ > -void __init create_boot_cache(struct kmem_cache *s, const char *name, > - unsigned int size, slab_flags_t flags, > - unsigned int useroffset, unsigned int usersize) > -{ > - int err; > - unsigned int align = ARCH_KMALLOC_MINALIGN; > - > - s->name = name; > - s->size = s->object_size = size; > - > - /* > - * For power of two sizes, guarantee natural alignment for kmalloc > - * caches, regardless of SL*B debugging options. > - */ > - if (is_power_of_2(size)) > - align = max(align, size); > - s->align = calculate_alignment(flags, align, size); > - > -#ifdef CONFIG_HARDENED_USERCOPY > - s->useroffset = useroffset; > - s->usersize = usersize; > -#endif > - > - err = __kmem_cache_create(s, flags); > - > - if (err) > - panic("Creation of kmalloc slab %s size=%u failed. Reason %d\n", > - name, size, err); > - > - s->refcount = -1; /* Exempt from merging for now */ > -} > - > -struct kmem_cache *__init create_kmalloc_cache(const char *name, > - unsigned int size, slab_flags_t flags, > - unsigned int useroffset, unsigned int usersize) > -{ > - struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); > - > - if (!s) > - panic("Out of memory when creating slab %s\n", name); > - > - create_boot_cache(s, name, size, flags | SLAB_KMALLOC, useroffset, > - usersize); > - list_add(&s->list, &slab_caches); > - s->refcount = 1; > - return s; > -} > - > -struct kmem_cache * > -kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1] __ro_after_init = > -{ /* initialization for https://bugs.llvm.org/show_bug.cgi?id=42570 */ }; > -EXPORT_SYMBOL(kmalloc_caches); > - > -/* > - * Conversion table for small slabs sizes / 8 to the index in the > - * kmalloc array. This is necessary for slabs < 192 since we have non power > - * of two cache sizes there. The size of larger slabs can be determined using > - * fls. > - */ > -static u8 size_index[24] __ro_after_init = { > - 3, /* 8 */ > - 4, /* 16 */ > - 5, /* 24 */ > - 5, /* 32 */ > - 6, /* 40 */ > - 6, /* 48 */ > - 6, /* 56 */ > - 6, /* 64 */ > - 1, /* 72 */ > - 1, /* 80 */ > - 1, /* 88 */ > - 1, /* 96 */ > - 7, /* 104 */ > - 7, /* 112 */ > - 7, /* 120 */ > - 7, /* 128 */ > - 2, /* 136 */ > - 2, /* 144 */ > - 2, /* 152 */ > - 2, /* 160 */ > - 2, /* 168 */ > - 2, /* 176 */ > - 2, /* 184 */ > - 2 /* 192 */ > -}; > - > -static inline unsigned int size_index_elem(unsigned int bytes) > -{ > - return (bytes - 1) / 8; > -} > - > -/* > - * Find the kmem_cache structure that serves a given size of > - * allocation > - */ > -struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags) > -{ > - unsigned int index; > - > - if (size <= 192) { > - if (!size) > - return ZERO_SIZE_PTR; > - > - index = size_index[size_index_elem(size)]; > - } else { > - if (WARN_ON_ONCE(size > KMALLOC_MAX_CACHE_SIZE)) > - return NULL; > - index = fls(size - 1); > - } > - > - return kmalloc_caches[kmalloc_type(flags)][index]; > -} > - > -size_t kmalloc_size_roundup(size_t size) > -{ > - struct kmem_cache *c; > - > - /* Short-circuit the 0 size case. */ > - if (unlikely(size == 0)) > - return 0; > - /* Short-circuit saturated "too-large" case. */ > - if (unlikely(size == SIZE_MAX)) > - return SIZE_MAX; > - /* Above the smaller buckets, size is a multiple of page size. */ > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return PAGE_SIZE << get_order(size); > - > - /* The flags don't matter since size_index is common to all. */ > - c = kmalloc_slab(size, GFP_KERNEL); > - return c ? c->object_size : 0; > -} > -EXPORT_SYMBOL(kmalloc_size_roundup); > - > -#ifdef CONFIG_ZONE_DMA > -#define KMALLOC_DMA_NAME(sz) .name[KMALLOC_DMA] = "dma-kmalloc-" #sz, > -#else > -#define KMALLOC_DMA_NAME(sz) > -#endif > - > -#ifdef CONFIG_MEMCG_KMEM > -#define KMALLOC_CGROUP_NAME(sz) .name[KMALLOC_CGROUP] = "kmalloc-cg-" #sz, > -#else > -#define KMALLOC_CGROUP_NAME(sz) > -#endif > - > -#ifndef CONFIG_SLUB_TINY > -#define KMALLOC_RCL_NAME(sz) .name[KMALLOC_RECLAIM] = "kmalloc-rcl-" #sz, > -#else > -#define KMALLOC_RCL_NAME(sz) > -#endif > - > -#define INIT_KMALLOC_INFO(__size, __short_size) \ > -{ \ > - .name[KMALLOC_NORMAL] = "kmalloc-" #__short_size, \ > - KMALLOC_RCL_NAME(__short_size) \ > - KMALLOC_CGROUP_NAME(__short_size) \ > - KMALLOC_DMA_NAME(__short_size) \ > - .size = __size, \ > -} > - > -/* > - * kmalloc_info[] is to make slub_debug=,kmalloc-xx option work at boot time. > - * kmalloc_index() supports up to 2^21=2MB, so the final entry of the table is > - * kmalloc-2M. > - */ > -const struct kmalloc_info_struct kmalloc_info[] __initconst = { > - INIT_KMALLOC_INFO(0, 0), > - INIT_KMALLOC_INFO(96, 96), > - INIT_KMALLOC_INFO(192, 192), > - INIT_KMALLOC_INFO(8, 8), > - INIT_KMALLOC_INFO(16, 16), > - INIT_KMALLOC_INFO(32, 32), > - INIT_KMALLOC_INFO(64, 64), > - INIT_KMALLOC_INFO(128, 128), > - INIT_KMALLOC_INFO(256, 256), > - INIT_KMALLOC_INFO(512, 512), > - INIT_KMALLOC_INFO(1024, 1k), > - INIT_KMALLOC_INFO(2048, 2k), > - INIT_KMALLOC_INFO(4096, 4k), > - INIT_KMALLOC_INFO(8192, 8k), > - INIT_KMALLOC_INFO(16384, 16k), > - INIT_KMALLOC_INFO(32768, 32k), > - INIT_KMALLOC_INFO(65536, 64k), > - INIT_KMALLOC_INFO(131072, 128k), > - INIT_KMALLOC_INFO(262144, 256k), > - INIT_KMALLOC_INFO(524288, 512k), > - INIT_KMALLOC_INFO(1048576, 1M), > - INIT_KMALLOC_INFO(2097152, 2M) > -}; > - > -/* > - * Patch up the size_index table if we have strange large alignment > - * requirements for the kmalloc array. This is only the case for > - * MIPS it seems. The standard arches will not generate any code here. > - * > - * Largest permitted alignment is 256 bytes due to the way we > - * handle the index determination for the smaller caches. > - * > - * Make sure that nothing crazy happens if someone starts tinkering > - * around with ARCH_KMALLOC_MINALIGN > - */ > -void __init setup_kmalloc_cache_index_table(void) > -{ > - unsigned int i; > - > - BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 || > - !is_power_of_2(KMALLOC_MIN_SIZE)); > - > - for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) { > - unsigned int elem = size_index_elem(i); > - > - if (elem >= ARRAY_SIZE(size_index)) > - break; > - size_index[elem] = KMALLOC_SHIFT_LOW; > - } > - > - if (KMALLOC_MIN_SIZE >= 64) { > - /* > - * The 96 byte sized cache is not used if the alignment > - * is 64 byte. > - */ > - for (i = 64 + 8; i <= 96; i += 8) > - size_index[size_index_elem(i)] = 7; > - > - } > - > - if (KMALLOC_MIN_SIZE >= 128) { > - /* > - * The 192 byte sized cache is not used if the alignment > - * is 128 byte. Redirect kmalloc to use the 256 byte cache > - * instead. > - */ > - for (i = 128 + 8; i <= 192; i += 8) > - size_index[size_index_elem(i)] = 8; > - } > -} > - > -static void __init > -new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags) > -{ > - if ((KMALLOC_RECLAIM != KMALLOC_NORMAL) && (type == KMALLOC_RECLAIM)) { > - flags |= SLAB_RECLAIM_ACCOUNT; > - } else if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_CGROUP)) { > - if (mem_cgroup_kmem_disabled()) { > - kmalloc_caches[type][idx] = kmalloc_caches[KMALLOC_NORMAL][idx]; > - return; > - } > - flags |= SLAB_ACCOUNT; > - } else if (IS_ENABLED(CONFIG_ZONE_DMA) && (type == KMALLOC_DMA)) { > - flags |= SLAB_CACHE_DMA; > - } > - > - kmalloc_caches[type][idx] = create_kmalloc_cache( > - kmalloc_info[idx].name[type], > - kmalloc_info[idx].size, flags, 0, > - kmalloc_info[idx].size); > - > - /* > - * If CONFIG_MEMCG_KMEM is enabled, disable cache merging for > - * KMALLOC_NORMAL caches. > - */ > - if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_NORMAL)) > - kmalloc_caches[type][idx]->refcount = -1; > -} > - > -/* > - * Create the kmalloc array. Some of the regular kmalloc arrays > - * may already have been created because they were needed to > - * enable allocations for slab creation. > - */ > -void __init create_kmalloc_caches(slab_flags_t flags) > -{ > - int i; > - enum kmalloc_cache_type type; > - > - /* > - * Including KMALLOC_CGROUP if CONFIG_MEMCG_KMEM defined > - */ > - for (type = KMALLOC_NORMAL; type < NR_KMALLOC_TYPES; type++) { > - for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) { > - if (!kmalloc_caches[type][i]) > - new_kmalloc_cache(i, type, flags); > - > - /* > - * Caches that are not of the two-to-the-power-of size. > - * These have to be created immediately after the > - * earlier power of two caches > - */ > - if (KMALLOC_MIN_SIZE <= 32 && i == 6 && > - !kmalloc_caches[type][1]) > - new_kmalloc_cache(1, type, flags); > - if (KMALLOC_MIN_SIZE <= 64 && i == 7 && > - !kmalloc_caches[type][2]) > - new_kmalloc_cache(2, type, flags); > - } > - } > - > - /* Kmalloc array is now usable */ > - slab_state = UP; > -} > - > -void free_large_kmalloc(struct folio *folio, void *object) > -{ > - unsigned int order = folio_order(folio); > - > - if (WARN_ON_ONCE(order == 0)) > - pr_warn_once("object pointer: 0x%p\n", object); > - > - kmemleak_free(object); > - kasan_kfree_large(object); > - kmsan_kfree_large(object); > - > - mod_lruvec_page_state(folio_page(folio, 0), NR_SLAB_UNRECLAIMABLE_B, > - -(PAGE_SIZE << order)); > - __free_pages(folio_page(folio, 0), order); > -} > - > -static void *__kmalloc_large_node(size_t size, gfp_t flags, int node); > -static __always_inline > -void *__do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller) > -{ > - struct kmem_cache *s; > - void *ret; > - > - if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) { > - ret = __kmalloc_large_node(size, flags, node); > - trace_kmalloc(caller, ret, size, > - PAGE_SIZE << get_order(size), flags, node); > - return ret; > - } > - > - s = kmalloc_slab(size, flags); > - > - if (unlikely(ZERO_OR_NULL_PTR(s))) > - return s; > - > - ret = __kmem_cache_alloc_node(s, flags, node, size, caller); > - ret = kasan_kmalloc(s, ret, size, flags); > - trace_kmalloc(caller, ret, size, s->size, flags, node); > - return ret; > -} > - > -void *__kmalloc_node(size_t size, gfp_t flags, int node) > -{ > - return __do_kmalloc_node(size, flags, node, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc_node); > - > -void *__kmalloc(size_t size, gfp_t flags) > -{ > - return __do_kmalloc_node(size, flags, NUMA_NO_NODE, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc); > - > -void *__kmalloc_node_track_caller(size_t size, gfp_t flags, > - int node, unsigned long caller) > -{ > - return __do_kmalloc_node(size, flags, node, caller); > -} > -EXPORT_SYMBOL(__kmalloc_node_track_caller); > - > -/** > - * kfree - free previously allocated memory > - * @object: pointer returned by kmalloc. > - * > - * If @object is NULL, no operation is performed. > - * > - * Don't free memory not originally allocated by kmalloc() > - * or you will run into trouble. > - */ > -void kfree(const void *object) > -{ > - struct folio *folio; > - struct slab *slab; > - struct kmem_cache *s; > - > - trace_kfree(_RET_IP_, object); > - > - if (unlikely(ZERO_OR_NULL_PTR(object))) > - return; > - > - folio = virt_to_folio(object); > - if (unlikely(!folio_test_slab(folio))) { > - free_large_kmalloc(folio, (void *)object); > - return; > - } > - > - slab = folio_slab(folio); > - s = slab->slab_cache; > - __kmem_cache_free(s, (void *)object, _RET_IP_); > -} > -EXPORT_SYMBOL(kfree); > - > -/** > - * __ksize -- Report full size of underlying allocation > - * @object: pointer to the object > - * > - * This should only be used internally to query the true size of allocations. > - * It is not meant to be a way to discover the usable size of an allocation > - * after the fact. Instead, use kmalloc_size_roundup(). Using memory beyond > - * the originally requested allocation size may trigger KASAN, UBSAN_BOUNDS, > - * and/or FORTIFY_SOURCE. > - * > - * Return: size of the actual memory used by @object in bytes > - */ > -size_t __ksize(const void *object) > -{ > - struct folio *folio; > - > - if (unlikely(object == ZERO_SIZE_PTR)) > - return 0; > - > - folio = virt_to_folio(object); > - > - if (unlikely(!folio_test_slab(folio))) { > - if (WARN_ON(folio_size(folio) <= KMALLOC_MAX_CACHE_SIZE)) > - return 0; > - if (WARN_ON(object != folio_address(folio))) > - return 0; > - return folio_size(folio); > - } > - > -#ifdef CONFIG_SLUB_DEBUG > - skip_orig_size_check(folio_slab(folio)->slab_cache, object); > -#endif > - > - return slab_ksize(folio_slab(folio)->slab_cache); > -} > - > -void *kmalloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size) > -{ > - void *ret = __kmem_cache_alloc_node(s, gfpflags, NUMA_NO_NODE, > - size, _RET_IP_); > - > - trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags, NUMA_NO_NODE); > - > - ret = kasan_kmalloc(s, ret, size, gfpflags); > - return ret; > -} > -EXPORT_SYMBOL(kmalloc_trace); > - > -void *kmalloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, > - int node, size_t size) > -{ > - void *ret = __kmem_cache_alloc_node(s, gfpflags, node, size, _RET_IP_); > - > - trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags, node); > - > - ret = kasan_kmalloc(s, ret, size, gfpflags); > - return ret; > -} > -EXPORT_SYMBOL(kmalloc_node_trace); > -#endif /* !CONFIG_SLOB */ > - > gfp_t kmalloc_fix_flags(gfp_t flags) > { > gfp_t invalid_mask = flags & GFP_SLAB_BUG_MASK; > @@ -1144,202 +684,44 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) > } > EXPORT_SYMBOL(kmalloc_large_node); > > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -/* Randomize a generic freelist */ > -static void freelist_randomize(struct rnd_state *state, unsigned int *list, > - unsigned int count) > -{ > - unsigned int rand; > - unsigned int i; > - > - for (i = 0; i < count; i++) > - list[i] = i; > - > - /* Fisher-Yates shuffle */ > - for (i = count - 1; i > 0; i--) { > - rand = prandom_u32_state(state); > - rand %= (i + 1); > - swap(list[i], list[rand]); > - } > -} > - > -/* Create a random sequence per cache */ > -int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, > - gfp_t gfp) > -{ > - struct rnd_state state; > - > - if (count < 2 || cachep->random_seq) > - return 0; > - > - cachep->random_seq = kcalloc(count, sizeof(unsigned int), gfp); > - if (!cachep->random_seq) > - return -ENOMEM; > - > - /* Get best entropy at this stage of boot */ > - prandom_seed_state(&state, get_random_long()); > - > - freelist_randomize(&state, cachep->random_seq, count); > - return 0; > -} > - > -/* Destroy the per-cache random freelist sequence */ > -void cache_random_seq_destroy(struct kmem_cache *cachep) > -{ > - kfree(cachep->random_seq); > - cachep->random_seq = NULL; > -} > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > - > -#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG) > -#ifdef CONFIG_SLAB > -#define SLABINFO_RIGHTS (0600) > -#else > -#define SLABINFO_RIGHTS (0400) > -#endif > - > -static void print_slabinfo_header(struct seq_file *m) > -{ > - /* > - * Output format version, so at least we can change it > - * without _too_ many complaints. > - */ > -#ifdef CONFIG_DEBUG_SLAB > - seq_puts(m, "slabinfo - version: 2.1 (statistics)\n"); > -#else > - seq_puts(m, "slabinfo - version: 2.1\n"); > -#endif > - seq_puts(m, "# name <active_objs> <num_objs> <objsize> <objperslab> <pagesperslab>"); > - seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>"); > - seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>"); > -#ifdef CONFIG_DEBUG_SLAB > - seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> <error> <maxfreeable> <nodeallocs> <remotefrees> <alienoverflow>"); > - seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>"); > -#endif > - seq_putc(m, '\n'); > -} > - > -static void *slab_start(struct seq_file *m, loff_t *pos) > -{ > - mutex_lock(&slab_mutex); > - return seq_list_start(&slab_caches, *pos); > -} > - > -static void *slab_next(struct seq_file *m, void *p, loff_t *pos) > -{ > - return seq_list_next(p, &slab_caches, pos); > -} > - > -static void slab_stop(struct seq_file *m, void *p) > -{ > - mutex_unlock(&slab_mutex); > -} > - > -static void cache_show(struct kmem_cache *s, struct seq_file *m) > +static __always_inline void * > +__do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) > { > - struct slabinfo sinfo; > + void *ret; > > - memset(&sinfo, 0, sizeof(sinfo)); > - get_slabinfo(s, &sinfo); > + gfp &= gfp_allowed_mask; > > - seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", > - s->name, sinfo.active_objs, sinfo.num_objs, s->size, > - sinfo.objects_per_slab, (1 << sinfo.cache_order)); > + might_alloc(gfp); > > - seq_printf(m, " : tunables %4u %4u %4u", > - sinfo.limit, sinfo.batchcount, sinfo.shared); > - seq_printf(m, " : slabdata %6lu %6lu %6lu", > - sinfo.active_slabs, sinfo.num_slabs, sinfo.shared_avail); > - slabinfo_show_stats(m, s); > - seq_putc(m, '\n'); > -} > + if (unlikely(!size)) > + ret = ZERO_SIZE_PTR; > + else > + ret = __kmalloc_large_node(size, gfp, node); > > -static int slab_show(struct seq_file *m, void *p) > -{ > - struct kmem_cache *s = list_entry(p, struct kmem_cache, list); > + trace_kmalloc(caller, ret, size, PAGE_SIZE << get_order(size), gfp, node); > > - if (p == slab_caches.next) > - print_slabinfo_header(m); > - cache_show(s, m); > - return 0; > + kmemleak_alloc(ret, size, 1, gfp); > + return ret; > } > > -void dump_unreclaimable_slab(void) > +void *__kmalloc(size_t size, gfp_t gfp) > { > - struct kmem_cache *s; > - struct slabinfo sinfo; > - > - /* > - * Here acquiring slab_mutex is risky since we don't prefer to get > - * sleep in oom path. But, without mutex hold, it may introduce a > - * risk of crash. > - * Use mutex_trylock to protect the list traverse, dump nothing > - * without acquiring the mutex. > - */ > - if (!mutex_trylock(&slab_mutex)) { > - pr_warn("excessive unreclaimable slab but cannot dump stats\n"); > - return; > - } > - > - pr_info("Unreclaimable slab info:\n"); > - pr_info("Name Used Total\n"); > - > - list_for_each_entry(s, &slab_caches, list) { > - if (s->flags & SLAB_RECLAIM_ACCOUNT) > - continue; > - > - get_slabinfo(s, &sinfo); > - > - if (sinfo.num_objs > 0) > - pr_info("%-17s %10luKB %10luKB\n", s->name, > - (sinfo.active_objs * s->size) / 1024, > - (sinfo.num_objs * s->size) / 1024); > - } > - mutex_unlock(&slab_mutex); > + return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_); > } > +EXPORT_SYMBOL(__kmalloc); > > -/* > - * slabinfo_op - iterator that generates /proc/slabinfo > - * > - * Output layout: > - * cache-name > - * num-active-objs > - * total-objs > - * object size > - * num-active-slabs > - * total-slabs > - * num-pages-per-slab > - * + further values on SMP and with statistics enabled > - */ > -static const struct seq_operations slabinfo_op = { > - .start = slab_start, > - .next = slab_next, > - .stop = slab_stop, > - .show = slab_show, > -}; > - > -static int slabinfo_open(struct inode *inode, struct file *file) > +void *__kmalloc_node(size_t size, gfp_t gfp, int node) > { > - return seq_open(file, &slabinfo_op); > + return __do_kmalloc_node(size, gfp, node, _RET_IP_); > } > +EXPORT_SYMBOL(__kmalloc_node); > > -static const struct proc_ops slabinfo_proc_ops = { > - .proc_flags = PROC_ENTRY_PERMANENT, > - .proc_open = slabinfo_open, > - .proc_read = seq_read, > - .proc_write = slabinfo_write, > - .proc_lseek = seq_lseek, > - .proc_release = seq_release, > -}; > - > -static int __init slab_proc_init(void) > +void *__kmalloc_node_track_caller(size_t size, gfp_t gfp, > + int node, unsigned long caller) > { > - proc_create("slabinfo", SLABINFO_RIGHTS, NULL, &slabinfo_proc_ops); > - return 0; > + return __do_kmalloc_node(size, gfp, node, caller); > } > -module_init(slab_proc_init); > - > -#endif /* CONFIG_SLAB || CONFIG_SLUB_DEBUG */ > +EXPORT_SYMBOL(__kmalloc_node_track_caller); > > static __always_inline __realloc_size(2) void * > __do_krealloc(const void *p, size_t new_size, gfp_t flags) > @@ -1402,6 +784,27 @@ void *krealloc(const void *p, size_t new_size, gfp_t flags) > } > EXPORT_SYMBOL(krealloc); > > +void kfree(const void *block) > +{ > + struct folio *sp; > + unsigned int order; > + > + trace_kfree(_RET_IP_, block); > + > + if (unlikely(ZERO_OR_NULL_PTR(block))) > + return; > + kmemleak_free(block); > + > + sp = virt_to_folio(block); > + BUG_ON(folio_test_slab(sp)); > + order = folio_order(sp); > + > + mod_node_page_state(folio_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > + -(PAGE_SIZE << order)); > + __free_pages(folio_page(sp, 0), order); > +} > +EXPORT_SYMBOL(kfree); > + > /** > * kfree_sensitive - Clear sensitive information in memory before freeing > * @p: object to free memory of > @@ -1427,6 +830,34 @@ void kfree_sensitive(const void *p) > } > EXPORT_SYMBOL(kfree_sensitive); > > +size_t kmalloc_size_roundup(size_t size) > +{ > + /* Short-circuit the 0 size case. */ > + if (unlikely(size == 0)) > + return 0; > + /* Short-circuit saturated "too-large" case. */ > + if (unlikely(size == SIZE_MAX)) > + return SIZE_MAX; > + > + return PAGE_SIZE << get_order(size); > +} > + > +EXPORT_SYMBOL(kmalloc_size_roundup); > + > +/* can't use ksize for kmem_cache_alloc memory, only kmalloc */ > +size_t __ksize(const void *block) > +{ > + struct folio *folio; > + > + BUG_ON(!block); > + if (unlikely(block == ZERO_SIZE_PTR)) > + return 0; > + > + folio = virt_to_folio(block); > + BUG_ON(folio_test_slab(folio)); > + return folio_size(folio); > +} > + > size_t ksize(const void *objp) > { > /* > @@ -1451,6 +882,131 @@ size_t ksize(const void *objp) > } > EXPORT_SYMBOL(ksize); > > +static void *__kmem_cache_alloc_node(struct kmem_cache *c, gfp_t flags, int node) > +{ > + void *b; > + > + flags &= gfp_allowed_mask; > + > + might_alloc(flags); > + > + b = __kmalloc_large_node(c->size, flags, node); > + trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); > + > + if (b && c->ctor) { > + WARN_ON_ONCE(flags & __GFP_ZERO); > + c->ctor(b); > + } > + > + kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); > + return b; > +} > + > +void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) > +{ > + return __kmem_cache_alloc_node(cachep, flags, NUMA_NO_NODE); > +} > +EXPORT_SYMBOL(kmem_cache_alloc); > + > + > +void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags) > +{ > + return __kmem_cache_alloc_node(cachep, flags, NUMA_NO_NODE); > +} > +EXPORT_SYMBOL(kmem_cache_alloc_lru); > + > +void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node) > +{ > + return __kmem_cache_alloc_node(cachep, gfp, node); > +} > +EXPORT_SYMBOL(kmem_cache_alloc_node); > + > +static void kmem_rcu_free(struct rcu_head *head) > +{ > + struct slab_rcu *slab_rcu = (struct slab_rcu *)head; > + void *b = (void *)slab_rcu - (slab_rcu->size - sizeof(struct slab_rcu)); > + > + kfree(b); > +} > + > +void kmem_cache_free(struct kmem_cache *c, void *b) > +{ > + kmemleak_free_recursive(b, c->flags); > + trace_kmem_cache_free(_RET_IP_, b, c); > + if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) { > + struct slab_rcu *slab_rcu; > + slab_rcu = b + (c->size - sizeof(struct slab_rcu)); > + slab_rcu->size = c->size; > + call_rcu(&slab_rcu->head, kmem_rcu_free); > + } else { > + kfree(b); > + } > +} > +EXPORT_SYMBOL(kmem_cache_free); > + > +void kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p) > +{ > + size_t i; > + > + for (i = 0; i < nr; i++) { > + if (s) > + kmem_cache_free(s, p[i]); > + else > + kfree(p[i]); > + } > +} > +EXPORT_SYMBOL(kmem_cache_free_bulk); > + > +int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr, > + void **p) > +{ > + size_t i; > + > + for (i = 0; i < nr; i++) { > + void *x = p[i] = kmem_cache_alloc(s, flags); > + > + if (!x) { > + kmem_cache_free_bulk(s, i, p); > + return 0; > + } > + } > + return i; > +} > +EXPORT_SYMBOL(kmem_cache_alloc_bulk); > + > +int __kmem_cache_shutdown(struct kmem_cache *c) > +{ > + /* No way to check for remaining objects */ > + return 0; > +} > + > +void __kmem_cache_release(struct kmem_cache *c) > +{ > +} > + > +int __kmem_cache_shrink(struct kmem_cache *d) > +{ > + return 0; > +} > + > +static struct kmem_cache kmem_cache_boot = { > + .name = "kmem_cache", > + .size = sizeof(struct kmem_cache), > + .flags = SLAB_PANIC, > + .align = ARCH_KMALLOC_MINALIGN, > +}; > + > +void __init kmem_cache_init(void) > +{ > + kmem_cache = &kmem_cache_boot; > + slab_state = UP; > +} > + > +void __init kmem_cache_init_late(void) > +{ > + slab_state = FULL; > +} > + > /* Tracepoints definitions. */ > EXPORT_TRACEPOINT_SYMBOL(kmalloc); > EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc); > diff --git a/mm/slob.c b/mm/slob.c > deleted file mode 100644 > index fe567fcfa3a3..000000000000 > --- a/mm/slob.c > +++ /dev/null > @@ -1,757 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * SLOB Allocator: Simple List Of Blocks > - * > - * Matt Mackall <mpm@selenic.com> 12/30/03 > - * > - * NUMA support by Paul Mundt, 2007. > - * > - * How SLOB works: > - * > - * The core of SLOB is a traditional K&R style heap allocator, with > - * support for returning aligned objects. The granularity of this > - * allocator is as little as 2 bytes, however typically most architectures > - * will require 4 bytes on 32-bit and 8 bytes on 64-bit. > - * > - * The slob heap is a set of linked list of pages from alloc_pages(), > - * and within each page, there is a singly-linked list of free blocks > - * (slob_t). The heap is grown on demand. To reduce fragmentation, > - * heap pages are segregated into three lists, with objects less than > - * 256 bytes, objects less than 1024 bytes, and all other objects. > - * > - * Allocation from heap involves first searching for a page with > - * sufficient free blocks (using a next-fit-like approach) followed by > - * a first-fit scan of the page. Deallocation inserts objects back > - * into the free list in address order, so this is effectively an > - * address-ordered first fit. > - * > - * Above this is an implementation of kmalloc/kfree. Blocks returned > - * from kmalloc are prepended with a 4-byte header with the kmalloc size. > - * If kmalloc is asked for objects of PAGE_SIZE or larger, it calls > - * alloc_pages() directly, allocating compound pages so the page order > - * does not have to be separately tracked. > - * These objects are detected in kfree() because folio_test_slab() > - * is false for them. > - * > - * SLAB is emulated on top of SLOB by simply calling constructors and > - * destructors for every SLAB allocation. Objects are returned with the > - * 4-byte alignment unless the SLAB_HWCACHE_ALIGN flag is set, in which > - * case the low-level allocator will fragment blocks to create the proper > - * alignment. Again, objects of page-size or greater are allocated by > - * calling alloc_pages(). As SLAB objects know their size, no separate > - * size bookkeeping is necessary and there is essentially no allocation > - * space overhead, and compound pages aren't needed for multi-page > - * allocations. > - * > - * NUMA support in SLOB is fairly simplistic, pushing most of the real > - * logic down to the page allocator, and simply doing the node accounting > - * on the upper levels. In the event that a node id is explicitly > - * provided, __alloc_pages_node() with the specified node id is used > - * instead. The common case (or when the node id isn't explicitly provided) > - * will default to the current node, as per numa_node_id(). > - * > - * Node aware pages are still inserted in to the global freelist, and > - * these are scanned for by matching against the node id encoded in the > - * page flags. As a result, block allocations that can be satisfied from > - * the freelist will only be done so on pages residing on the same node, > - * in order to prevent random node placement. > - */ > - > -#include <linux/kernel.h> > -#include <linux/slab.h> > - > -#include <linux/mm.h> > -#include <linux/swap.h> /* struct reclaim_state */ > -#include <linux/cache.h> > -#include <linux/init.h> > -#include <linux/export.h> > -#include <linux/rcupdate.h> > -#include <linux/list.h> > -#include <linux/kmemleak.h> > - > -#include <trace/events/kmem.h> > - > -#include <linux/atomic.h> > - > -#include "slab.h" > -/* > - * slob_block has a field 'units', which indicates size of block if +ve, > - * or offset of next block if -ve (in SLOB_UNITs). > - * > - * Free blocks of size 1 unit simply contain the offset of the next block. > - * Those with larger size contain their size in the first SLOB_UNIT of > - * memory, and the offset of the next free block in the second SLOB_UNIT. > - */ > -#if PAGE_SIZE <= (32767 * 2) > -typedef s16 slobidx_t; > -#else > -typedef s32 slobidx_t; > -#endif > - > -struct slob_block { > - slobidx_t units; > -}; > -typedef struct slob_block slob_t; > - > -/* > - * All partially free slob pages go on these lists. > - */ > -#define SLOB_BREAK1 256 > -#define SLOB_BREAK2 1024 > -static LIST_HEAD(free_slob_small); > -static LIST_HEAD(free_slob_medium); > -static LIST_HEAD(free_slob_large); > - > -/* > - * slob_page_free: true for pages on free_slob_pages list. > - */ > -static inline int slob_page_free(struct slab *slab) > -{ > - return PageSlobFree(slab_page(slab)); > -} > - > -static void set_slob_page_free(struct slab *slab, struct list_head *list) > -{ > - list_add(&slab->slab_list, list); > - __SetPageSlobFree(slab_page(slab)); > -} > - > -static inline void clear_slob_page_free(struct slab *slab) > -{ > - list_del(&slab->slab_list); > - __ClearPageSlobFree(slab_page(slab)); > -} > - > -#define SLOB_UNIT sizeof(slob_t) > -#define SLOB_UNITS(size) DIV_ROUND_UP(size, SLOB_UNIT) > - > -/* > - * struct slob_rcu is inserted at the tail of allocated slob blocks, which > - * were created with a SLAB_TYPESAFE_BY_RCU slab. slob_rcu is used to free > - * the block using call_rcu. > - */ > -struct slob_rcu { > - struct rcu_head head; > - int size; > -}; > - > -/* > - * slob_lock protects all slob allocator structures. > - */ > -static DEFINE_SPINLOCK(slob_lock); > - > -/* > - * Encode the given size and next info into a free slob block s. > - */ > -static void set_slob(slob_t *s, slobidx_t size, slob_t *next) > -{ > - slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); > - slobidx_t offset = next - base; > - > - if (size > 1) { > - s[0].units = size; > - s[1].units = offset; > - } else > - s[0].units = -offset; > -} > - > -/* > - * Return the size of a slob block. > - */ > -static slobidx_t slob_units(slob_t *s) > -{ > - if (s->units > 0) > - return s->units; > - return 1; > -} > - > -/* > - * Return the next free slob block pointer after this one. > - */ > -static slob_t *slob_next(slob_t *s) > -{ > - slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); > - slobidx_t next; > - > - if (s[0].units < 0) > - next = -s[0].units; > - else > - next = s[1].units; > - return base+next; > -} > - > -/* > - * Returns true if s is the last free block in its page. > - */ > -static int slob_last(slob_t *s) > -{ > - return !((unsigned long)slob_next(s) & ~PAGE_MASK); > -} > - > -static void *slob_new_pages(gfp_t gfp, int order, int node) > -{ > - struct page *page; > - > -#ifdef CONFIG_NUMA > - if (node != NUMA_NO_NODE) > - page = __alloc_pages_node(node, gfp, order); > - else > -#endif > - page = alloc_pages(gfp, order); > - > - if (!page) > - return NULL; > - > - mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE_B, > - PAGE_SIZE << order); > - return page_address(page); > -} > - > -static void slob_free_pages(void *b, int order) > -{ > - struct page *sp = virt_to_page(b); > - > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += 1 << order; > - > - mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > - -(PAGE_SIZE << order)); > - __free_pages(sp, order); > -} > - > -/* > - * slob_page_alloc() - Allocate a slob block within a given slob_page sp. > - * @sp: Page to look in. > - * @size: Size of the allocation. > - * @align: Allocation alignment. > - * @align_offset: Offset in the allocated block that will be aligned. > - * @page_removed_from_list: Return parameter. > - * > - * Tries to find a chunk of memory at least @size bytes big within @page. > - * > - * Return: Pointer to memory if allocated, %NULL otherwise. If the > - * allocation fills up @page then the page is removed from the > - * freelist, in this case @page_removed_from_list will be set to > - * true (set to false otherwise). > - */ > -static void *slob_page_alloc(struct slab *sp, size_t size, int align, > - int align_offset, bool *page_removed_from_list) > -{ > - slob_t *prev, *cur, *aligned = NULL; > - int delta = 0, units = SLOB_UNITS(size); > - > - *page_removed_from_list = false; > - for (prev = NULL, cur = sp->freelist; ; prev = cur, cur = slob_next(cur)) { > - slobidx_t avail = slob_units(cur); > - > - /* > - * 'aligned' will hold the address of the slob block so that the > - * address 'aligned'+'align_offset' is aligned according to the > - * 'align' parameter. This is for kmalloc() which prepends the > - * allocated block with its size, so that the block itself is > - * aligned when needed. > - */ > - if (align) { > - aligned = (slob_t *) > - (ALIGN((unsigned long)cur + align_offset, align) > - - align_offset); > - delta = aligned - cur; > - } > - if (avail >= units + delta) { /* room enough? */ > - slob_t *next; > - > - if (delta) { /* need to fragment head to align? */ > - next = slob_next(cur); > - set_slob(aligned, avail - delta, next); > - set_slob(cur, delta, aligned); > - prev = cur; > - cur = aligned; > - avail = slob_units(cur); > - } > - > - next = slob_next(cur); > - if (avail == units) { /* exact fit? unlink. */ > - if (prev) > - set_slob(prev, slob_units(prev), next); > - else > - sp->freelist = next; > - } else { /* fragment */ > - if (prev) > - set_slob(prev, slob_units(prev), cur + units); > - else > - sp->freelist = cur + units; > - set_slob(cur + units, avail - units, next); > - } > - > - sp->units -= units; > - if (!sp->units) { > - clear_slob_page_free(sp); > - *page_removed_from_list = true; > - } > - return cur; > - } > - if (slob_last(cur)) > - return NULL; > - } > -} > - > -/* > - * slob_alloc: entry point into the slob allocator. > - */ > -static void *slob_alloc(size_t size, gfp_t gfp, int align, int node, > - int align_offset) > -{ > - struct folio *folio; > - struct slab *sp; > - struct list_head *slob_list; > - slob_t *b = NULL; > - unsigned long flags; > - bool _unused; > - > - if (size < SLOB_BREAK1) > - slob_list = &free_slob_small; > - else if (size < SLOB_BREAK2) > - slob_list = &free_slob_medium; > - else > - slob_list = &free_slob_large; > - > - spin_lock_irqsave(&slob_lock, flags); > - /* Iterate through each partially free page, try to find room */ > - list_for_each_entry(sp, slob_list, slab_list) { > - bool page_removed_from_list = false; > -#ifdef CONFIG_NUMA > - /* > - * If there's a node specification, search for a partial > - * page with a matching node id in the freelist. > - */ > - if (node != NUMA_NO_NODE && slab_nid(sp) != node) > - continue; > -#endif > - /* Enough room on this page? */ > - if (sp->units < SLOB_UNITS(size)) > - continue; > - > - b = slob_page_alloc(sp, size, align, align_offset, &page_removed_from_list); > - if (!b) > - continue; > - > - /* > - * If slob_page_alloc() removed sp from the list then we > - * cannot call list functions on sp. If so allocation > - * did not fragment the page anyway so optimisation is > - * unnecessary. > - */ > - if (!page_removed_from_list) { > - /* > - * Improve fragment distribution and reduce our average > - * search time by starting our next search here. (see > - * Knuth vol 1, sec 2.5, pg 449) > - */ > - if (!list_is_first(&sp->slab_list, slob_list)) > - list_rotate_to_front(&sp->slab_list, slob_list); > - } > - break; > - } > - spin_unlock_irqrestore(&slob_lock, flags); > - > - /* Not enough space: must allocate a new page */ > - if (!b) { > - b = slob_new_pages(gfp & ~__GFP_ZERO, 0, node); > - if (!b) > - return NULL; > - folio = virt_to_folio(b); > - __folio_set_slab(folio); > - sp = folio_slab(folio); > - > - spin_lock_irqsave(&slob_lock, flags); > - sp->units = SLOB_UNITS(PAGE_SIZE); > - sp->freelist = b; > - INIT_LIST_HEAD(&sp->slab_list); > - set_slob(b, SLOB_UNITS(PAGE_SIZE), b + SLOB_UNITS(PAGE_SIZE)); > - set_slob_page_free(sp, slob_list); > - b = slob_page_alloc(sp, size, align, align_offset, &_unused); > - BUG_ON(!b); > - spin_unlock_irqrestore(&slob_lock, flags); > - } > - if (unlikely(gfp & __GFP_ZERO)) > - memset(b, 0, size); > - return b; > -} > - > -/* > - * slob_free: entry point into the slob allocator. > - */ > -static void slob_free(void *block, int size) > -{ > - struct slab *sp; > - slob_t *prev, *next, *b = (slob_t *)block; > - slobidx_t units; > - unsigned long flags; > - struct list_head *slob_list; > - > - if (unlikely(ZERO_OR_NULL_PTR(block))) > - return; > - BUG_ON(!size); > - > - sp = virt_to_slab(block); > - units = SLOB_UNITS(size); > - > - spin_lock_irqsave(&slob_lock, flags); > - > - if (sp->units + units == SLOB_UNITS(PAGE_SIZE)) { > - /* Go directly to page allocator. Do not pass slob allocator */ > - if (slob_page_free(sp)) > - clear_slob_page_free(sp); > - spin_unlock_irqrestore(&slob_lock, flags); > - __folio_clear_slab(slab_folio(sp)); > - slob_free_pages(b, 0); > - return; > - } > - > - if (!slob_page_free(sp)) { > - /* This slob page is about to become partially free. Easy! */ > - sp->units = units; > - sp->freelist = b; > - set_slob(b, units, > - (void *)((unsigned long)(b + > - SLOB_UNITS(PAGE_SIZE)) & PAGE_MASK)); > - if (size < SLOB_BREAK1) > - slob_list = &free_slob_small; > - else if (size < SLOB_BREAK2) > - slob_list = &free_slob_medium; > - else > - slob_list = &free_slob_large; > - set_slob_page_free(sp, slob_list); > - goto out; > - } > - > - /* > - * Otherwise the page is already partially free, so find reinsertion > - * point. > - */ > - sp->units += units; > - > - if (b < (slob_t *)sp->freelist) { > - if (b + units == sp->freelist) { > - units += slob_units(sp->freelist); > - sp->freelist = slob_next(sp->freelist); > - } > - set_slob(b, units, sp->freelist); > - sp->freelist = b; > - } else { > - prev = sp->freelist; > - next = slob_next(prev); > - while (b > next) { > - prev = next; > - next = slob_next(prev); > - } > - > - if (!slob_last(prev) && b + units == next) { > - units += slob_units(next); > - set_slob(b, units, slob_next(next)); > - } else > - set_slob(b, units, next); > - > - if (prev + slob_units(prev) == b) { > - units = slob_units(b) + slob_units(prev); > - set_slob(prev, units, slob_next(b)); > - } else > - set_slob(prev, slob_units(prev), b); > - } > -out: > - spin_unlock_irqrestore(&slob_lock, flags); > -} > - > -#ifdef CONFIG_PRINTK > -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) > -{ > - kpp->kp_ptr = object; > - kpp->kp_slab = slab; > -} > -#endif > - > -/* > - * End of slob allocator proper. Begin kmem_cache_alloc and kmalloc frontend. > - */ > - > -static __always_inline void * > -__do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) > -{ > - unsigned int *m; > - unsigned int minalign; > - void *ret; > - > - minalign = max_t(unsigned int, ARCH_KMALLOC_MINALIGN, > - arch_slab_minalign()); > - gfp &= gfp_allowed_mask; > - > - might_alloc(gfp); > - > - if (size < PAGE_SIZE - minalign) { > - int align = minalign; > - > - /* > - * For power of two sizes, guarantee natural alignment for > - * kmalloc()'d objects. > - */ > - if (is_power_of_2(size)) > - align = max_t(unsigned int, minalign, size); > - > - if (!size) > - return ZERO_SIZE_PTR; > - > - m = slob_alloc(size + minalign, gfp, align, node, minalign); > - > - if (!m) > - return NULL; > - *m = size; > - ret = (void *)m + minalign; > - > - trace_kmalloc(caller, ret, size, size + minalign, gfp, node); > - } else { > - unsigned int order = get_order(size); > - > - if (likely(order)) > - gfp |= __GFP_COMP; > - ret = slob_new_pages(gfp, order, node); > - > - trace_kmalloc(caller, ret, size, PAGE_SIZE << order, gfp, node); > - } > - > - kmemleak_alloc(ret, size, 1, gfp); > - return ret; > -} > - > -void *__kmalloc(size_t size, gfp_t gfp) > -{ > - return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc); > - > -void *__kmalloc_node_track_caller(size_t size, gfp_t gfp, > - int node, unsigned long caller) > -{ > - return __do_kmalloc_node(size, gfp, node, caller); > -} > -EXPORT_SYMBOL(__kmalloc_node_track_caller); > - > -void kfree(const void *block) > -{ > - struct folio *sp; > - > - trace_kfree(_RET_IP_, block); > - > - if (unlikely(ZERO_OR_NULL_PTR(block))) > - return; > - kmemleak_free(block); > - > - sp = virt_to_folio(block); > - if (folio_test_slab(sp)) { > - unsigned int align = max_t(unsigned int, > - ARCH_KMALLOC_MINALIGN, > - arch_slab_minalign()); > - unsigned int *m = (unsigned int *)(block - align); > - > - slob_free(m, *m + align); > - } else { > - unsigned int order = folio_order(sp); > - > - mod_node_page_state(folio_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > - -(PAGE_SIZE << order)); > - __free_pages(folio_page(sp, 0), order); > - > - } > -} > -EXPORT_SYMBOL(kfree); > - > -size_t kmalloc_size_roundup(size_t size) > -{ > - /* Short-circuit the 0 size case. */ > - if (unlikely(size == 0)) > - return 0; > - /* Short-circuit saturated "too-large" case. */ > - if (unlikely(size == SIZE_MAX)) > - return SIZE_MAX; > - > - return ALIGN(size, ARCH_KMALLOC_MINALIGN); > -} > - > -EXPORT_SYMBOL(kmalloc_size_roundup); > - > -/* can't use ksize for kmem_cache_alloc memory, only kmalloc */ > -size_t __ksize(const void *block) > -{ > - struct folio *folio; > - unsigned int align; > - unsigned int *m; > - > - BUG_ON(!block); > - if (unlikely(block == ZERO_SIZE_PTR)) > - return 0; > - > - folio = virt_to_folio(block); > - if (unlikely(!folio_test_slab(folio))) > - return folio_size(folio); > - > - align = max_t(unsigned int, ARCH_KMALLOC_MINALIGN, > - arch_slab_minalign()); > - m = (unsigned int *)(block - align); > - return SLOB_UNITS(*m) * SLOB_UNIT; > -} > - > -int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags) > -{ > - if (flags & SLAB_TYPESAFE_BY_RCU) { > - /* leave room for rcu footer at the end of object */ > - c->size += sizeof(struct slob_rcu); > - } > - > - /* Actual size allocated */ > - c->size = SLOB_UNITS(c->size) * SLOB_UNIT; > - c->flags = flags; > - return 0; > -} > - > -static void *slob_alloc_node(struct kmem_cache *c, gfp_t flags, int node) > -{ > - void *b; > - > - flags &= gfp_allowed_mask; > - > - might_alloc(flags); > - > - if (c->size < PAGE_SIZE) { > - b = slob_alloc(c->size, flags, c->align, node, 0); > - trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); > - } else { > - b = slob_new_pages(flags, get_order(c->size), node); > - trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); > - } > - > - if (b && c->ctor) { > - WARN_ON_ONCE(flags & __GFP_ZERO); > - c->ctor(b); > - } > - > - kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); > - return b; > -} > - > -void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - return slob_alloc_node(cachep, flags, NUMA_NO_NODE); > -} > -EXPORT_SYMBOL(kmem_cache_alloc); > - > - > -void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags) > -{ > - return slob_alloc_node(cachep, flags, NUMA_NO_NODE); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_lru); > - > -void *__kmalloc_node(size_t size, gfp_t gfp, int node) > -{ > - return __do_kmalloc_node(size, gfp, node, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc_node); > - > -void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node) > -{ > - return slob_alloc_node(cachep, gfp, node); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_node); > - > -static void __kmem_cache_free(void *b, int size) > -{ > - if (size < PAGE_SIZE) > - slob_free(b, size); > - else > - slob_free_pages(b, get_order(size)); > -} > - > -static void kmem_rcu_free(struct rcu_head *head) > -{ > - struct slob_rcu *slob_rcu = (struct slob_rcu *)head; > - void *b = (void *)slob_rcu - (slob_rcu->size - sizeof(struct slob_rcu)); > - > - __kmem_cache_free(b, slob_rcu->size); > -} > - > -void kmem_cache_free(struct kmem_cache *c, void *b) > -{ > - kmemleak_free_recursive(b, c->flags); > - trace_kmem_cache_free(_RET_IP_, b, c); > - if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) { > - struct slob_rcu *slob_rcu; > - slob_rcu = b + (c->size - sizeof(struct slob_rcu)); > - slob_rcu->size = c->size; > - call_rcu(&slob_rcu->head, kmem_rcu_free); > - } else { > - __kmem_cache_free(b, c->size); > - } > -} > -EXPORT_SYMBOL(kmem_cache_free); > - > -void kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p) > -{ > - size_t i; > - > - for (i = 0; i < nr; i++) { > - if (s) > - kmem_cache_free(s, p[i]); > - else > - kfree(p[i]); > - } > -} > -EXPORT_SYMBOL(kmem_cache_free_bulk); > - > -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr, > - void **p) > -{ > - size_t i; > - > - for (i = 0; i < nr; i++) { > - void *x = p[i] = kmem_cache_alloc(s, flags); > - > - if (!x) { > - kmem_cache_free_bulk(s, i, p); > - return 0; > - } > - } > - return i; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_bulk); > - > -int __kmem_cache_shutdown(struct kmem_cache *c) > -{ > - /* No way to check for remaining objects */ > - return 0; > -} > - > -void __kmem_cache_release(struct kmem_cache *c) > -{ > -} > - > -int __kmem_cache_shrink(struct kmem_cache *d) > -{ > - return 0; > -} > - > -static struct kmem_cache kmem_cache_boot = { > - .name = "kmem_cache", > - .size = sizeof(struct kmem_cache), > - .flags = SLAB_PANIC, > - .align = ARCH_KMALLOC_MINALIGN, > -}; > - > -void __init kmem_cache_init(void) > -{ > - kmem_cache = &kmem_cache_boot; > - slab_state = UP; > -} > - > -void __init kmem_cache_init_late(void) > -{ > - slab_state = FULL; > -} > diff --git a/mm/slub.c b/mm/slub.c > deleted file mode 100644 > index 39327e98fce3..000000000000 > --- a/mm/slub.c > +++ /dev/null > @@ -1,6506 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * SLUB: A slab allocator that limits cache line use instead of queuing > - * objects in per cpu and per node lists. > - * > - * The allocator synchronizes using per slab locks or atomic operations > - * and only uses a centralized lock to manage a pool of partial slabs. > - * > - * (C) 2007 SGI, Christoph Lameter > - * (C) 2011 Linux Foundation, Christoph Lameter > - */ > - > -#include <linux/mm.h> > -#include <linux/swap.h> /* struct reclaim_state */ > -#include <linux/module.h> > -#include <linux/bit_spinlock.h> > -#include <linux/interrupt.h> > -#include <linux/swab.h> > -#include <linux/bitops.h> > -#include <linux/slab.h> > -#include "slab.h" > -#include <linux/proc_fs.h> > -#include <linux/seq_file.h> > -#include <linux/kasan.h> > -#include <linux/kmsan.h> > -#include <linux/cpu.h> > -#include <linux/cpuset.h> > -#include <linux/mempolicy.h> > -#include <linux/ctype.h> > -#include <linux/stackdepot.h> > -#include <linux/debugobjects.h> > -#include <linux/kallsyms.h> > -#include <linux/kfence.h> > -#include <linux/memory.h> > -#include <linux/math64.h> > -#include <linux/fault-inject.h> > -#include <linux/stacktrace.h> > -#include <linux/prefetch.h> > -#include <linux/memcontrol.h> > -#include <linux/random.h> > -#include <kunit/test.h> > -#include <kunit/test-bug.h> > -#include <linux/sort.h> > - > -#include <linux/debugfs.h> > -#include <trace/events/kmem.h> > - > -#include "internal.h" > - > -/* > - * Lock order: > - * 1. slab_mutex (Global Mutex) > - * 2. node->list_lock (Spinlock) > - * 3. kmem_cache->cpu_slab->lock (Local lock) > - * 4. slab_lock(slab) (Only on some arches) > - * 5. object_map_lock (Only for debugging) > - * > - * slab_mutex > - * > - * The role of the slab_mutex is to protect the list of all the slabs > - * and to synchronize major metadata changes to slab cache structures. > - * Also synchronizes memory hotplug callbacks. > - * > - * slab_lock > - * > - * The slab_lock is a wrapper around the page lock, thus it is a bit > - * spinlock. > - * > - * The slab_lock is only used on arches that do not have the ability > - * to do a cmpxchg_double. It only protects: > - * > - * A. slab->freelist -> List of free objects in a slab > - * B. slab->inuse -> Number of objects in use > - * C. slab->objects -> Number of objects in slab > - * D. slab->frozen -> frozen state > - * > - * Frozen slabs > - * > - * If a slab is frozen then it is exempt from list management. It is not > - * on any list except per cpu partial list. The processor that froze the > - * slab is the one who can perform list operations on the slab. Other > - * processors may put objects onto the freelist but the processor that > - * froze the slab is the only one that can retrieve the objects from the > - * slab's freelist. > - * > - * list_lock > - * > - * The list_lock protects the partial and full list on each node and > - * the partial slab counter. If taken then no new slabs may be added or > - * removed from the lists nor make the number of partial slabs be modified. > - * (Note that the total number of slabs is an atomic value that may be > - * modified without taking the list lock). > - * > - * The list_lock is a centralized lock and thus we avoid taking it as > - * much as possible. As long as SLUB does not have to handle partial > - * slabs, operations can continue without any centralized lock. F.e. > - * allocating a long series of objects that fill up slabs does not require > - * the list lock. > - * > - * For debug caches, all allocations are forced to go through a list_lock > - * protected region to serialize against concurrent validation. > - * > - * cpu_slab->lock local lock > - * > - * This locks protect slowpath manipulation of all kmem_cache_cpu fields > - * except the stat counters. This is a percpu structure manipulated only by > - * the local cpu, so the lock protects against being preempted or interrupted > - * by an irq. Fast path operations rely on lockless operations instead. > - * > - * On PREEMPT_RT, the local lock neither disables interrupts nor preemption > - * which means the lockless fastpath cannot be used as it might interfere with > - * an in-progress slow path operations. In this case the local lock is always > - * taken but it still utilizes the freelist for the common operations. > - * > - * lockless fastpaths > - * > - * The fast path allocation (slab_alloc_node()) and freeing (do_slab_free()) > - * are fully lockless when satisfied from the percpu slab (and when > - * cmpxchg_double is possible to use, otherwise slab_lock is taken). > - * They also don't disable preemption or migration or irqs. They rely on > - * the transaction id (tid) field to detect being preempted or moved to > - * another cpu. > - * > - * irq, preemption, migration considerations > - * > - * Interrupts are disabled as part of list_lock or local_lock operations, or > - * around the slab_lock operation, in order to make the slab allocator safe > - * to use in the context of an irq. > - * > - * In addition, preemption (or migration on PREEMPT_RT) is disabled in the > - * allocation slowpath, bulk allocation, and put_cpu_partial(), so that the > - * local cpu doesn't change in the process and e.g. the kmem_cache_cpu pointer > - * doesn't have to be revalidated in each section protected by the local lock. > - * > - * SLUB assigns one slab for allocation to each processor. > - * Allocations only occur from these slabs called cpu slabs. > - * > - * Slabs with free elements are kept on a partial list and during regular > - * operations no list for full slabs is used. If an object in a full slab is > - * freed then the slab will show up again on the partial lists. > - * We track full slabs for debugging purposes though because otherwise we > - * cannot scan all objects. > - * > - * Slabs are freed when they become empty. Teardown and setup is > - * minimal so we rely on the page allocators per cpu caches for > - * fast frees and allocs. > - * > - * slab->frozen The slab is frozen and exempt from list processing. > - * This means that the slab is dedicated to a purpose > - * such as satisfying allocations for a specific > - * processor. Objects may be freed in the slab while > - * it is frozen but slab_free will then skip the usual > - * list operations. It is up to the processor holding > - * the slab to integrate the slab into the slab lists > - * when the slab is no longer needed. > - * > - * One use of this flag is to mark slabs that are > - * used for allocations. Then such a slab becomes a cpu > - * slab. The cpu slab may be equipped with an additional > - * freelist that allows lockless access to > - * free objects in addition to the regular freelist > - * that requires the slab lock. > - * > - * SLAB_DEBUG_FLAGS Slab requires special handling due to debug > - * options set. This moves slab handling out of > - * the fast path and disables lockless freelists. > - */ > - > -/* > - * We could simply use migrate_disable()/enable() but as long as it's a > - * function call even on !PREEMPT_RT, use inline preempt_disable() there. > - */ > -#ifndef CONFIG_PREEMPT_RT > -#define slub_get_cpu_ptr(var) get_cpu_ptr(var) > -#define slub_put_cpu_ptr(var) put_cpu_ptr(var) > -#define USE_LOCKLESS_FAST_PATH() (true) > -#else > -#define slub_get_cpu_ptr(var) \ > -({ \ > - migrate_disable(); \ > - this_cpu_ptr(var); \ > -}) > -#define slub_put_cpu_ptr(var) \ > -do { \ > - (void)(var); \ > - migrate_enable(); \ > -} while (0) > -#define USE_LOCKLESS_FAST_PATH() (false) > -#endif > - > -#ifndef CONFIG_SLUB_TINY > -#define __fastpath_inline __always_inline > -#else > -#define __fastpath_inline > -#endif > - > -#ifdef CONFIG_SLUB_DEBUG > -#ifdef CONFIG_SLUB_DEBUG_ON > -DEFINE_STATIC_KEY_TRUE(slub_debug_enabled); > -#else > -DEFINE_STATIC_KEY_FALSE(slub_debug_enabled); > -#endif > -#endif /* CONFIG_SLUB_DEBUG */ > - > -/* Structure holding parameters for get_partial() call chain */ > -struct partial_context { > - struct slab **slab; > - gfp_t flags; > - unsigned int orig_size; > -}; > - > -static inline bool kmem_cache_debug(struct kmem_cache *s) > -{ > - return kmem_cache_debug_flags(s, SLAB_DEBUG_FLAGS); > -} > - > -static inline bool slub_debug_orig_size(struct kmem_cache *s) > -{ > - return (kmem_cache_debug_flags(s, SLAB_STORE_USER) && > - (s->flags & SLAB_KMALLOC)); > -} > - > -void *fixup_red_left(struct kmem_cache *s, void *p) > -{ > - if (kmem_cache_debug_flags(s, SLAB_RED_ZONE)) > - p += s->red_left_pad; > - > - return p; > -} > - > -static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s) > -{ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - return !kmem_cache_debug(s); > -#else > - return false; > -#endif > -} > - > -/* > - * Issues still to be resolved: > - * > - * - Support PAGE_ALLOC_DEBUG. Should be easy to do. > - * > - * - Variable sizing of the per node arrays > - */ > - > -/* Enable to log cmpxchg failures */ > -#undef SLUB_DEBUG_CMPXCHG > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Minimum number of partial slabs. These will be left on the partial > - * lists even if they are empty. kmem_cache_shrink may reclaim them. > - */ > -#define MIN_PARTIAL 5 > - > -/* > - * Maximum number of desirable partial slabs. > - * The existence of more partial slabs makes kmem_cache_shrink > - * sort the partial list by the number of objects in use. > - */ > -#define MAX_PARTIAL 10 > -#else > -#define MIN_PARTIAL 0 > -#define MAX_PARTIAL 0 > -#endif > - > -#define DEBUG_DEFAULT_FLAGS (SLAB_CONSISTENCY_CHECKS | SLAB_RED_ZONE | \ > - SLAB_POISON | SLAB_STORE_USER) > - > -/* > - * These debug flags cannot use CMPXCHG because there might be consistency > - * issues when checking or reading debug information > - */ > -#define SLAB_NO_CMPXCHG (SLAB_CONSISTENCY_CHECKS | SLAB_STORE_USER | \ > - SLAB_TRACE) > - > - > -/* > - * Debugging flags that require metadata to be stored in the slab. These get > - * disabled when slub_debug=O is used and a cache's min order increases with > - * metadata. > - */ > -#define DEBUG_METADATA_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) > - > -#define OO_SHIFT 16 > -#define OO_MASK ((1 << OO_SHIFT) - 1) > -#define MAX_OBJS_PER_PAGE 32767 /* since slab.objects is u15 */ > - > -/* Internal SLUB flags */ > -/* Poison object */ > -#define __OBJECT_POISON ((slab_flags_t __force)0x80000000U) > -/* Use cmpxchg_double */ > -#define __CMPXCHG_DOUBLE ((slab_flags_t __force)0x40000000U) > - > -/* > - * Tracking user of a slab. > - */ > -#define TRACK_ADDRS_COUNT 16 > -struct track { > - unsigned long addr; /* Called from address */ > -#ifdef CONFIG_STACKDEPOT > - depot_stack_handle_t handle; > -#endif > - int cpu; /* Was running on cpu */ > - int pid; /* Pid context */ > - unsigned long when; /* When did the operation occur */ > -}; > - > -enum track_item { TRACK_ALLOC, TRACK_FREE }; > - > -#ifdef SLAB_SUPPORTS_SYSFS > -static int sysfs_slab_add(struct kmem_cache *); > -static int sysfs_slab_alias(struct kmem_cache *, const char *); > -#else > -static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; } > -static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) > - { return 0; } > -#endif > - > -#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) > -static void debugfs_slab_add(struct kmem_cache *); > -#else > -static inline void debugfs_slab_add(struct kmem_cache *s) { } > -#endif > - > -static inline void stat(const struct kmem_cache *s, enum stat_item si) > -{ > -#ifdef CONFIG_SLUB_STATS > - /* > - * The rmw is racy on a preemptible kernel but this is acceptable, so > - * avoid this_cpu_add()'s irq-disable overhead. > - */ > - raw_cpu_inc(s->cpu_slab->stat[si]); > -#endif > -} > - > -/* > - * Tracks for which NUMA nodes we have kmem_cache_nodes allocated. > - * Corresponds to node_state[N_NORMAL_MEMORY], but can temporarily > - * differ during memory hotplug/hotremove operations. > - * Protected by slab_mutex. > - */ > -static nodemask_t slab_nodes; > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Workqueue used for flush_cpu_slab(). > - */ > -static struct workqueue_struct *flushwq; > -#endif > - > -/******************************************************************** > - * Core slab cache functions > - *******************************************************************/ > - > -/* > - * Returns freelist pointer (ptr). With hardening, this is obfuscated > - * with an XOR of the address where the pointer is held and a per-cache > - * random number. > - */ > -static inline void *freelist_ptr(const struct kmem_cache *s, void *ptr, > - unsigned long ptr_addr) > -{ > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - /* > - * When CONFIG_KASAN_SW/HW_TAGS is enabled, ptr_addr might be tagged. > - * Normally, this doesn't cause any issues, as both set_freepointer() > - * and get_freepointer() are called with a pointer with the same tag. > - * However, there are some issues with CONFIG_SLUB_DEBUG code. For > - * example, when __free_slub() iterates over objects in a cache, it > - * passes untagged pointers to check_object(). check_object() in turns > - * calls get_freepointer() with an untagged pointer, which causes the > - * freepointer to be restored incorrectly. > - */ > - return (void *)((unsigned long)ptr ^ s->random ^ > - swab((unsigned long)kasan_reset_tag((void *)ptr_addr))); > -#else > - return ptr; > -#endif > -} > - > -/* Returns the freelist pointer recorded at location ptr_addr. */ > -static inline void *freelist_dereference(const struct kmem_cache *s, > - void *ptr_addr) > -{ > - return freelist_ptr(s, (void *)*(unsigned long *)(ptr_addr), > - (unsigned long)ptr_addr); > -} > - > -static inline void *get_freepointer(struct kmem_cache *s, void *object) > -{ > - object = kasan_reset_tag(object); > - return freelist_dereference(s, object + s->offset); > -} > - > -#ifndef CONFIG_SLUB_TINY > -static void prefetch_freepointer(const struct kmem_cache *s, void *object) > -{ > - prefetchw(object + s->offset); > -} > -#endif > - > -/* > - * When running under KMSAN, get_freepointer_safe() may return an uninitialized > - * pointer value in the case the current thread loses the race for the next > - * memory chunk in the freelist. In that case this_cpu_cmpxchg_double() in > - * slab_alloc_node() will fail, so the uninitialized value won't be used, but > - * KMSAN will still check all arguments of cmpxchg because of imperfect > - * handling of inline assembly. > - * To work around this problem, we apply __no_kmsan_checks to ensure that > - * get_freepointer_safe() returns initialized memory. > - */ > -__no_kmsan_checks > -static inline void *get_freepointer_safe(struct kmem_cache *s, void *object) > -{ > - unsigned long freepointer_addr; > - void *p; > - > - if (!debug_pagealloc_enabled_static()) > - return get_freepointer(s, object); > - > - object = kasan_reset_tag(object); > - freepointer_addr = (unsigned long)object + s->offset; > - copy_from_kernel_nofault(&p, (void **)freepointer_addr, sizeof(p)); > - return freelist_ptr(s, p, freepointer_addr); > -} > - > -static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) > -{ > - unsigned long freeptr_addr = (unsigned long)object + s->offset; > - > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - BUG_ON(object == fp); /* naive detection of double free or corruption */ > -#endif > - > - freeptr_addr = (unsigned long)kasan_reset_tag((void *)freeptr_addr); > - *(void **)freeptr_addr = freelist_ptr(s, fp, freeptr_addr); > -} > - > -/* Loop over all objects in a slab */ > -#define for_each_object(__p, __s, __addr, __objects) \ > - for (__p = fixup_red_left(__s, __addr); \ > - __p < (__addr) + (__objects) * (__s)->size; \ > - __p += (__s)->size) > - > -static inline unsigned int order_objects(unsigned int order, unsigned int size) > -{ > - return ((unsigned int)PAGE_SIZE << order) / size; > -} > - > -static inline struct kmem_cache_order_objects oo_make(unsigned int order, > - unsigned int size) > -{ > - struct kmem_cache_order_objects x = { > - (order << OO_SHIFT) + order_objects(order, size) > - }; > - > - return x; > -} > - > -static inline unsigned int oo_order(struct kmem_cache_order_objects x) > -{ > - return x.x >> OO_SHIFT; > -} > - > -static inline unsigned int oo_objects(struct kmem_cache_order_objects x) > -{ > - return x.x & OO_MASK; > -} > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -static void slub_set_cpu_partial(struct kmem_cache *s, unsigned int nr_objects) > -{ > - unsigned int nr_slabs; > - > - s->cpu_partial = nr_objects; > - > - /* > - * We take the number of objects but actually limit the number of > - * slabs on the per cpu partial list, in order to limit excessive > - * growth of the list. For simplicity we assume that the slabs will > - * be half-full. > - */ > - nr_slabs = DIV_ROUND_UP(nr_objects * 2, oo_objects(s->oo)); > - s->cpu_partial_slabs = nr_slabs; > -} > -#else > -static inline void > -slub_set_cpu_partial(struct kmem_cache *s, unsigned int nr_objects) > -{ > -} > -#endif /* CONFIG_SLUB_CPU_PARTIAL */ > - > -/* > - * Per slab locking using the pagelock > - */ > -static __always_inline void slab_lock(struct slab *slab) > -{ > - struct page *page = slab_page(slab); > - > - VM_BUG_ON_PAGE(PageTail(page), page); > - bit_spin_lock(PG_locked, &page->flags); > -} > - > -static __always_inline void slab_unlock(struct slab *slab) > -{ > - struct page *page = slab_page(slab); > - > - VM_BUG_ON_PAGE(PageTail(page), page); > - __bit_spin_unlock(PG_locked, &page->flags); > -} > - > -/* > - * Interrupts must be disabled (for the fallback code to work right), typically > - * by an _irqsave() lock variant. On PREEMPT_RT the preempt_disable(), which is > - * part of bit_spin_lock(), is sufficient because the policy is not to allow any > - * allocation/ free operation in hardirq context. Therefore nothing can > - * interrupt the operation. > - */ > -static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab, > - void *freelist_old, unsigned long counters_old, > - void *freelist_new, unsigned long counters_new, > - const char *n) > -{ > - if (USE_LOCKLESS_FAST_PATH()) > - lockdep_assert_irqs_disabled(); > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ > - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) > - if (s->flags & __CMPXCHG_DOUBLE) { > - if (cmpxchg_double(&slab->freelist, &slab->counters, > - freelist_old, counters_old, > - freelist_new, counters_new)) > - return true; > - } else > -#endif > - { > - slab_lock(slab); > - if (slab->freelist == freelist_old && > - slab->counters == counters_old) { > - slab->freelist = freelist_new; > - slab->counters = counters_new; > - slab_unlock(slab); > - return true; > - } > - slab_unlock(slab); > - } > - > - cpu_relax(); > - stat(s, CMPXCHG_DOUBLE_FAIL); > - > -#ifdef SLUB_DEBUG_CMPXCHG > - pr_info("%s %s: cmpxchg double redo ", n, s->name); > -#endif > - > - return false; > -} > - > -static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab, > - void *freelist_old, unsigned long counters_old, > - void *freelist_new, unsigned long counters_new, > - const char *n) > -{ > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ > - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) > - if (s->flags & __CMPXCHG_DOUBLE) { > - if (cmpxchg_double(&slab->freelist, &slab->counters, > - freelist_old, counters_old, > - freelist_new, counters_new)) > - return true; > - } else > -#endif > - { > - unsigned long flags; > - > - local_irq_save(flags); > - slab_lock(slab); > - if (slab->freelist == freelist_old && > - slab->counters == counters_old) { > - slab->freelist = freelist_new; > - slab->counters = counters_new; > - slab_unlock(slab); > - local_irq_restore(flags); > - return true; > - } > - slab_unlock(slab); > - local_irq_restore(flags); > - } > - > - cpu_relax(); > - stat(s, CMPXCHG_DOUBLE_FAIL); > - > -#ifdef SLUB_DEBUG_CMPXCHG > - pr_info("%s %s: cmpxchg double redo ", n, s->name); > -#endif > - > - return false; > -} > - > -#ifdef CONFIG_SLUB_DEBUG > -static unsigned long object_map[BITS_TO_LONGS(MAX_OBJS_PER_PAGE)]; > -static DEFINE_SPINLOCK(object_map_lock); > - > -static void __fill_map(unsigned long *obj_map, struct kmem_cache *s, > - struct slab *slab) > -{ > - void *addr = slab_address(slab); > - void *p; > - > - bitmap_zero(obj_map, slab->objects); > - > - for (p = slab->freelist; p; p = get_freepointer(s, p)) > - set_bit(__obj_to_index(s, addr, p), obj_map); > -} > - > -#if IS_ENABLED(CONFIG_KUNIT) > -static bool slab_add_kunit_errors(void) > -{ > - struct kunit_resource *resource; > - > - if (!kunit_get_current_test()) > - return false; > - > - resource = kunit_find_named_resource(current->kunit_test, "slab_errors"); > - if (!resource) > - return false; > - > - (*(int *)resource->data)++; > - kunit_put_resource(resource); > - return true; > -} > -#else > -static inline bool slab_add_kunit_errors(void) { return false; } > -#endif > - > -static inline unsigned int size_from_object(struct kmem_cache *s) > -{ > - if (s->flags & SLAB_RED_ZONE) > - return s->size - s->red_left_pad; > - > - return s->size; > -} > - > -static inline void *restore_red_left(struct kmem_cache *s, void *p) > -{ > - if (s->flags & SLAB_RED_ZONE) > - p -= s->red_left_pad; > - > - return p; > -} > - > -/* > - * Debug settings: > - */ > -#if defined(CONFIG_SLUB_DEBUG_ON) > -static slab_flags_t slub_debug = DEBUG_DEFAULT_FLAGS; > -#else > -static slab_flags_t slub_debug; > -#endif > - > -static char *slub_debug_string; > -static int disable_higher_order_debug; > - > -/* > - * slub is about to manipulate internal object metadata. This memory lies > - * outside the range of the allocated object, so accessing it would normally > - * be reported by kasan as a bounds error. metadata_access_enable() is used > - * to tell kasan that these accesses are OK. > - */ > -static inline void metadata_access_enable(void) > -{ > - kasan_disable_current(); > -} > - > -static inline void metadata_access_disable(void) > -{ > - kasan_enable_current(); > -} > - > -/* > - * Object debugging > - */ > - > -/* Verify that a pointer has an address that is valid within a slab page */ > -static inline int check_valid_pointer(struct kmem_cache *s, > - struct slab *slab, void *object) > -{ > - void *base; > - > - if (!object) > - return 1; > - > - base = slab_address(slab); > - object = kasan_reset_tag(object); > - object = restore_red_left(s, object); > - if (object < base || object >= base + slab->objects * s->size || > - (object - base) % s->size) { > - return 0; > - } > - > - return 1; > -} > - > -static void print_section(char *level, char *text, u8 *addr, > - unsigned int length) > -{ > - metadata_access_enable(); > - print_hex_dump(level, text, DUMP_PREFIX_ADDRESS, > - 16, 1, kasan_reset_tag((void *)addr), length, 1); > - metadata_access_disable(); > -} > - > -/* > - * See comment in calculate_sizes(). > - */ > -static inline bool freeptr_outside_object(struct kmem_cache *s) > -{ > - return s->offset >= s->inuse; > -} > - > -/* > - * Return offset of the end of info block which is inuse + free pointer if > - * not overlapping with object. > - */ > -static inline unsigned int get_info_end(struct kmem_cache *s) > -{ > - if (freeptr_outside_object(s)) > - return s->inuse + sizeof(void *); > - else > - return s->inuse; > -} > - > -static struct track *get_track(struct kmem_cache *s, void *object, > - enum track_item alloc) > -{ > - struct track *p; > - > - p = object + get_info_end(s); > - > - return kasan_reset_tag(p + alloc); > -} > - > -#ifdef CONFIG_STACKDEPOT > -static noinline depot_stack_handle_t set_track_prepare(void) > -{ > - depot_stack_handle_t handle; > - unsigned long entries[TRACK_ADDRS_COUNT]; > - unsigned int nr_entries; > - > - nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 3); > - handle = stack_depot_save(entries, nr_entries, GFP_NOWAIT); > - > - return handle; > -} > -#else > -static inline depot_stack_handle_t set_track_prepare(void) > -{ > - return 0; > -} > -#endif > - > -static void set_track_update(struct kmem_cache *s, void *object, > - enum track_item alloc, unsigned long addr, > - depot_stack_handle_t handle) > -{ > - struct track *p = get_track(s, object, alloc); > - > -#ifdef CONFIG_STACKDEPOT > - p->handle = handle; > -#endif > - p->addr = addr; > - p->cpu = smp_processor_id(); > - p->pid = current->pid; > - p->when = jiffies; > -} > - > -static __always_inline void set_track(struct kmem_cache *s, void *object, > - enum track_item alloc, unsigned long addr) > -{ > - depot_stack_handle_t handle = set_track_prepare(); > - > - set_track_update(s, object, alloc, addr, handle); > -} > - > -static void init_tracking(struct kmem_cache *s, void *object) > -{ > - struct track *p; > - > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - p = get_track(s, object, TRACK_ALLOC); > - memset(p, 0, 2*sizeof(struct track)); > -} > - > -static void print_track(const char *s, struct track *t, unsigned long pr_time) > -{ > - depot_stack_handle_t handle __maybe_unused; > - > - if (!t->addr) > - return; > - > - pr_err("%s in %pS age=%lu cpu=%u pid=%d\n", > - s, (void *)t->addr, pr_time - t->when, t->cpu, t->pid); > -#ifdef CONFIG_STACKDEPOT > - handle = READ_ONCE(t->handle); > - if (handle) > - stack_depot_print(handle); > - else > - pr_err("object allocation/free stack trace missing\n"); > -#endif > -} > - > -void print_tracking(struct kmem_cache *s, void *object) > -{ > - unsigned long pr_time = jiffies; > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - print_track("Allocated", get_track(s, object, TRACK_ALLOC), pr_time); > - print_track("Freed", get_track(s, object, TRACK_FREE), pr_time); > -} > - > -static void print_slab_info(const struct slab *slab) > -{ > - struct folio *folio = (struct folio *)slab_folio(slab); > - > - pr_err("Slab 0x%p objects=%u used=%u fp=0x%p flags=%pGp\n", > - slab, slab->objects, slab->inuse, slab->freelist, > - folio_flags(folio, 0)); > -} > - > -/* > - * kmalloc caches has fixed sizes (mostly power of 2), and kmalloc() API > - * family will round up the real request size to these fixed ones, so > - * there could be an extra area than what is requested. Save the original > - * request size in the meta data area, for better debug and sanity check. > - */ > -static inline void set_orig_size(struct kmem_cache *s, > - void *object, unsigned int orig_size) > -{ > - void *p = kasan_reset_tag(object); > - > - if (!slub_debug_orig_size(s)) > - return; > - > -#ifdef CONFIG_KASAN_GENERIC > - /* > - * KASAN could save its free meta data in object's data area at > - * offset 0, if the size is larger than 'orig_size', it will > - * overlap the data redzone in [orig_size+1, object_size], and > - * the check should be skipped. > - */ > - if (kasan_metadata_size(s, true) > orig_size) > - orig_size = s->object_size; > -#endif > - > - p += get_info_end(s); > - p += sizeof(struct track) * 2; > - > - *(unsigned int *)p = orig_size; > -} > - > -static inline unsigned int get_orig_size(struct kmem_cache *s, void *object) > -{ > - void *p = kasan_reset_tag(object); > - > - if (!slub_debug_orig_size(s)) > - return s->object_size; > - > - p += get_info_end(s); > - p += sizeof(struct track) * 2; > - > - return *(unsigned int *)p; > -} > - > -void skip_orig_size_check(struct kmem_cache *s, const void *object) > -{ > - set_orig_size(s, (void *)object, s->object_size); > -} > - > -static void slab_bug(struct kmem_cache *s, char *fmt, ...) > -{ > - struct va_format vaf; > - va_list args; > - > - va_start(args, fmt); > - vaf.fmt = fmt; > - vaf.va = &args; > - pr_err("=============================================================================\n"); > - pr_err("BUG %s (%s): %pV\n", s->name, print_tainted(), &vaf); > - pr_err("-----------------------------------------------------------------------------\n\n"); > - va_end(args); > -} > - > -__printf(2, 3) > -static void slab_fix(struct kmem_cache *s, char *fmt, ...) > -{ > - struct va_format vaf; > - va_list args; > - > - if (slab_add_kunit_errors()) > - return; > - > - va_start(args, fmt); > - vaf.fmt = fmt; > - vaf.va = &args; > - pr_err("FIX %s: %pV\n", s->name, &vaf); > - va_end(args); > -} > - > -static void print_trailer(struct kmem_cache *s, struct slab *slab, u8 *p) > -{ > - unsigned int off; /* Offset of last byte */ > - u8 *addr = slab_address(slab); > - > - print_tracking(s, p); > - > - print_slab_info(slab); > - > - pr_err("Object 0x%p @offset=%tu fp=0x%p\n\n", > - p, p - addr, get_freepointer(s, p)); > - > - if (s->flags & SLAB_RED_ZONE) > - print_section(KERN_ERR, "Redzone ", p - s->red_left_pad, > - s->red_left_pad); > - else if (p > addr + 16) > - print_section(KERN_ERR, "Bytes b4 ", p - 16, 16); > - > - print_section(KERN_ERR, "Object ", p, > - min_t(unsigned int, s->object_size, PAGE_SIZE)); > - if (s->flags & SLAB_RED_ZONE) > - print_section(KERN_ERR, "Redzone ", p + s->object_size, > - s->inuse - s->object_size); > - > - off = get_info_end(s); > - > - if (s->flags & SLAB_STORE_USER) > - off += 2 * sizeof(struct track); > - > - if (slub_debug_orig_size(s)) > - off += sizeof(unsigned int); > - > - off += kasan_metadata_size(s, false); > - > - if (off != size_from_object(s)) > - /* Beginning of the filler is the free pointer */ > - print_section(KERN_ERR, "Padding ", p + off, > - size_from_object(s) - off); > - > - dump_stack(); > -} > - > -static void object_err(struct kmem_cache *s, struct slab *slab, > - u8 *object, char *reason) > -{ > - if (slab_add_kunit_errors()) > - return; > - > - slab_bug(s, "%s", reason); > - print_trailer(s, slab, object); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > - > -static bool freelist_corrupted(struct kmem_cache *s, struct slab *slab, > - void **freelist, void *nextfree) > -{ > - if ((s->flags & SLAB_CONSISTENCY_CHECKS) && > - !check_valid_pointer(s, slab, nextfree) && freelist) { > - object_err(s, slab, *freelist, "Freechain corrupt"); > - *freelist = NULL; > - slab_fix(s, "Isolate corrupted freechain"); > - return true; > - } > - > - return false; > -} > - > -static __printf(3, 4) void slab_err(struct kmem_cache *s, struct slab *slab, > - const char *fmt, ...) > -{ > - va_list args; > - char buf[100]; > - > - if (slab_add_kunit_errors()) > - return; > - > - va_start(args, fmt); > - vsnprintf(buf, sizeof(buf), fmt, args); > - va_end(args); > - slab_bug(s, "%s", buf); > - print_slab_info(slab); > - dump_stack(); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > - > -static void init_object(struct kmem_cache *s, void *object, u8 val) > -{ > - u8 *p = kasan_reset_tag(object); > - unsigned int poison_size = s->object_size; > - > - if (s->flags & SLAB_RED_ZONE) { > - memset(p - s->red_left_pad, val, s->red_left_pad); > - > - if (slub_debug_orig_size(s) && val == SLUB_RED_ACTIVE) { > - /* > - * Redzone the extra allocated space by kmalloc than > - * requested, and the poison size will be limited to > - * the original request size accordingly. > - */ > - poison_size = get_orig_size(s, object); > - } > - } > - > - if (s->flags & __OBJECT_POISON) { > - memset(p, POISON_FREE, poison_size - 1); > - p[poison_size - 1] = POISON_END; > - } > - > - if (s->flags & SLAB_RED_ZONE) > - memset(p + poison_size, val, s->inuse - poison_size); > -} > - > -static void restore_bytes(struct kmem_cache *s, char *message, u8 data, > - void *from, void *to) > -{ > - slab_fix(s, "Restoring %s 0x%p-0x%p=0x%x", message, from, to - 1, data); > - memset(from, data, to - from); > -} > - > -static int check_bytes_and_report(struct kmem_cache *s, struct slab *slab, > - u8 *object, char *what, > - u8 *start, unsigned int value, unsigned int bytes) > -{ > - u8 *fault; > - u8 *end; > - u8 *addr = slab_address(slab); > - > - metadata_access_enable(); > - fault = memchr_inv(kasan_reset_tag(start), value, bytes); > - metadata_access_disable(); > - if (!fault) > - return 1; > - > - end = start + bytes; > - while (end > fault && end[-1] == value) > - end--; > - > - if (slab_add_kunit_errors()) > - goto skip_bug_print; > - > - slab_bug(s, "%s overwritten", what); > - pr_err("0x%p-0x%p @offset=%tu. First byte 0x%x instead of 0x%x\n", > - fault, end - 1, fault - addr, > - fault[0], value); > - print_trailer(s, slab, object); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > - > -skip_bug_print: > - restore_bytes(s, what, value, fault, end); > - return 0; > -} > - > -/* > - * Object layout: > - * > - * object address > - * Bytes of the object to be managed. > - * If the freepointer may overlay the object then the free > - * pointer is at the middle of the object. > - * > - * Poisoning uses 0x6b (POISON_FREE) and the last byte is > - * 0xa5 (POISON_END) > - * > - * object + s->object_size > - * Padding to reach word boundary. This is also used for Redzoning. > - * Padding is extended by another word if Redzoning is enabled and > - * object_size == inuse. > - * > - * We fill with 0xbb (RED_INACTIVE) for inactive objects and with > - * 0xcc (RED_ACTIVE) for objects in use. > - * > - * object + s->inuse > - * Meta data starts here. > - * > - * A. Free pointer (if we cannot overwrite object on free) > - * B. Tracking data for SLAB_STORE_USER > - * C. Original request size for kmalloc object (SLAB_STORE_USER enabled) > - * D. Padding to reach required alignment boundary or at minimum > - * one word if debugging is on to be able to detect writes > - * before the word boundary. > - * > - * Padding is done using 0x5a (POISON_INUSE) > - * > - * object + s->size > - * Nothing is used beyond s->size. > - * > - * If slabcaches are merged then the object_size and inuse boundaries are mostly > - * ignored. And therefore no slab options that rely on these boundaries > - * may be used with merged slabcaches. > - */ > - > -static int check_pad_bytes(struct kmem_cache *s, struct slab *slab, u8 *p) > -{ > - unsigned long off = get_info_end(s); /* The end of info */ > - > - if (s->flags & SLAB_STORE_USER) { > - /* We also have user information there */ > - off += 2 * sizeof(struct track); > - > - if (s->flags & SLAB_KMALLOC) > - off += sizeof(unsigned int); > - } > - > - off += kasan_metadata_size(s, false); > - > - if (size_from_object(s) == off) > - return 1; > - > - return check_bytes_and_report(s, slab, p, "Object padding", > - p + off, POISON_INUSE, size_from_object(s) - off); > -} > - > -/* Check the pad bytes at the end of a slab page */ > -static void slab_pad_check(struct kmem_cache *s, struct slab *slab) > -{ > - u8 *start; > - u8 *fault; > - u8 *end; > - u8 *pad; > - int length; > - int remainder; > - > - if (!(s->flags & SLAB_POISON)) > - return; > - > - start = slab_address(slab); > - length = slab_size(slab); > - end = start + length; > - remainder = length % s->size; > - if (!remainder) > - return; > - > - pad = end - remainder; > - metadata_access_enable(); > - fault = memchr_inv(kasan_reset_tag(pad), POISON_INUSE, remainder); > - metadata_access_disable(); > - if (!fault) > - return; > - while (end > fault && end[-1] == POISON_INUSE) > - end--; > - > - slab_err(s, slab, "Padding overwritten. 0x%p-0x%p @offset=%tu", > - fault, end - 1, fault - start); > - print_section(KERN_ERR, "Padding ", pad, remainder); > - > - restore_bytes(s, "slab padding", POISON_INUSE, fault, end); > -} > - > -static int check_object(struct kmem_cache *s, struct slab *slab, > - void *object, u8 val) > -{ > - u8 *p = object; > - u8 *endobject = object + s->object_size; > - unsigned int orig_size; > - > - if (s->flags & SLAB_RED_ZONE) { > - if (!check_bytes_and_report(s, slab, object, "Left Redzone", > - object - s->red_left_pad, val, s->red_left_pad)) > - return 0; > - > - if (!check_bytes_and_report(s, slab, object, "Right Redzone", > - endobject, val, s->inuse - s->object_size)) > - return 0; > - > - if (slub_debug_orig_size(s) && val == SLUB_RED_ACTIVE) { > - orig_size = get_orig_size(s, object); > - > - if (s->object_size > orig_size && > - !check_bytes_and_report(s, slab, object, > - "kmalloc Redzone", p + orig_size, > - val, s->object_size - orig_size)) { > - return 0; > - } > - } > - } else { > - if ((s->flags & SLAB_POISON) && s->object_size < s->inuse) { > - check_bytes_and_report(s, slab, p, "Alignment padding", > - endobject, POISON_INUSE, > - s->inuse - s->object_size); > - } > - } > - > - if (s->flags & SLAB_POISON) { > - if (val != SLUB_RED_ACTIVE && (s->flags & __OBJECT_POISON) && > - (!check_bytes_and_report(s, slab, p, "Poison", p, > - POISON_FREE, s->object_size - 1) || > - !check_bytes_and_report(s, slab, p, "End Poison", > - p + s->object_size - 1, POISON_END, 1))) > - return 0; > - /* > - * check_pad_bytes cleans up on its own. > - */ > - check_pad_bytes(s, slab, p); > - } > - > - if (!freeptr_outside_object(s) && val == SLUB_RED_ACTIVE) > - /* > - * Object and freepointer overlap. Cannot check > - * freepointer while object is allocated. > - */ > - return 1; > - > - /* Check free pointer validity */ > - if (!check_valid_pointer(s, slab, get_freepointer(s, p))) { > - object_err(s, slab, p, "Freepointer corrupt"); > - /* > - * No choice but to zap it and thus lose the remainder > - * of the free objects in this slab. May cause > - * another error because the object count is now wrong. > - */ > - set_freepointer(s, p, NULL); > - return 0; > - } > - return 1; > -} > - > -static int check_slab(struct kmem_cache *s, struct slab *slab) > -{ > - int maxobj; > - > - if (!folio_test_slab(slab_folio(slab))) { > - slab_err(s, slab, "Not a valid slab page"); > - return 0; > - } > - > - maxobj = order_objects(slab_order(slab), s->size); > - if (slab->objects > maxobj) { > - slab_err(s, slab, "objects %u > max %u", > - slab->objects, maxobj); > - return 0; > - } > - if (slab->inuse > slab->objects) { > - slab_err(s, slab, "inuse %u > max %u", > - slab->inuse, slab->objects); > - return 0; > - } > - /* Slab_pad_check fixes things up after itself */ > - slab_pad_check(s, slab); > - return 1; > -} > - > -/* > - * Determine if a certain object in a slab is on the freelist. Must hold the > - * slab lock to guarantee that the chains are in a consistent state. > - */ > -static int on_freelist(struct kmem_cache *s, struct slab *slab, void *search) > -{ > - int nr = 0; > - void *fp; > - void *object = NULL; > - int max_objects; > - > - fp = slab->freelist; > - while (fp && nr <= slab->objects) { > - if (fp == search) > - return 1; > - if (!check_valid_pointer(s, slab, fp)) { > - if (object) { > - object_err(s, slab, object, > - "Freechain corrupt"); > - set_freepointer(s, object, NULL); > - } else { > - slab_err(s, slab, "Freepointer corrupt"); > - slab->freelist = NULL; > - slab->inuse = slab->objects; > - slab_fix(s, "Freelist cleared"); > - return 0; > - } > - break; > - } > - object = fp; > - fp = get_freepointer(s, object); > - nr++; > - } > - > - max_objects = order_objects(slab_order(slab), s->size); > - if (max_objects > MAX_OBJS_PER_PAGE) > - max_objects = MAX_OBJS_PER_PAGE; > - > - if (slab->objects != max_objects) { > - slab_err(s, slab, "Wrong number of objects. Found %d but should be %d", > - slab->objects, max_objects); > - slab->objects = max_objects; > - slab_fix(s, "Number of objects adjusted"); > - } > - if (slab->inuse != slab->objects - nr) { > - slab_err(s, slab, "Wrong object count. Counter is %d but counted were %d", > - slab->inuse, slab->objects - nr); > - slab->inuse = slab->objects - nr; > - slab_fix(s, "Object count adjusted"); > - } > - return search == NULL; > -} > - > -static void trace(struct kmem_cache *s, struct slab *slab, void *object, > - int alloc) > -{ > - if (s->flags & SLAB_TRACE) { > - pr_info("TRACE %s %s 0x%p inuse=%d fp=0x%p\n", > - s->name, > - alloc ? "alloc" : "free", > - object, slab->inuse, > - slab->freelist); > - > - if (!alloc) > - print_section(KERN_INFO, "Object ", (void *)object, > - s->object_size); > - > - dump_stack(); > - } > -} > - > -/* > - * Tracking of fully allocated slabs for debugging purposes. > - */ > -static void add_full(struct kmem_cache *s, > - struct kmem_cache_node *n, struct slab *slab) > -{ > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - lockdep_assert_held(&n->list_lock); > - list_add(&slab->slab_list, &n->full); > -} > - > -static void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, struct slab *slab) > -{ > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - lockdep_assert_held(&n->list_lock); > - list_del(&slab->slab_list); > -} > - > -/* Tracking of the number of slabs for debugging purposes */ > -static inline unsigned long slabs_node(struct kmem_cache *s, int node) > -{ > - struct kmem_cache_node *n = get_node(s, node); > - > - return atomic_long_read(&n->nr_slabs); > -} > - > -static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) > -{ > - return atomic_long_read(&n->nr_slabs); > -} > - > -static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects) > -{ > - struct kmem_cache_node *n = get_node(s, node); > - > - /* > - * May be called early in order to allocate a slab for the > - * kmem_cache_node structure. Solve the chicken-egg > - * dilemma by deferring the increment of the count during > - * bootstrap (see early_kmem_cache_node_alloc). > - */ > - if (likely(n)) { > - atomic_long_inc(&n->nr_slabs); > - atomic_long_add(objects, &n->total_objects); > - } > -} > -static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects) > -{ > - struct kmem_cache_node *n = get_node(s, node); > - > - atomic_long_dec(&n->nr_slabs); > - atomic_long_sub(objects, &n->total_objects); > -} > - > -/* Object debug checks for alloc/free paths */ > -static void setup_object_debug(struct kmem_cache *s, void *object) > -{ > - if (!kmem_cache_debug_flags(s, SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON)) > - return; > - > - init_object(s, object, SLUB_RED_INACTIVE); > - init_tracking(s, object); > -} > - > -static > -void setup_slab_debug(struct kmem_cache *s, struct slab *slab, void *addr) > -{ > - if (!kmem_cache_debug_flags(s, SLAB_POISON)) > - return; > - > - metadata_access_enable(); > - memset(kasan_reset_tag(addr), POISON_INUSE, slab_size(slab)); > - metadata_access_disable(); > -} > - > -static inline int alloc_consistency_checks(struct kmem_cache *s, > - struct slab *slab, void *object) > -{ > - if (!check_slab(s, slab)) > - return 0; > - > - if (!check_valid_pointer(s, slab, object)) { > - object_err(s, slab, object, "Freelist Pointer check fails"); > - return 0; > - } > - > - if (!check_object(s, slab, object, SLUB_RED_INACTIVE)) > - return 0; > - > - return 1; > -} > - > -static noinline bool alloc_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *object, int orig_size) > -{ > - if (s->flags & SLAB_CONSISTENCY_CHECKS) { > - if (!alloc_consistency_checks(s, slab, object)) > - goto bad; > - } > - > - /* Success. Perform special debug activities for allocs */ > - trace(s, slab, object, 1); > - set_orig_size(s, object, orig_size); > - init_object(s, object, SLUB_RED_ACTIVE); > - return true; > - > -bad: > - if (folio_test_slab(slab_folio(slab))) { > - /* > - * If this is a slab page then lets do the best we can > - * to avoid issues in the future. Marking all objects > - * as used avoids touching the remaining objects. > - */ > - slab_fix(s, "Marking all objects used"); > - slab->inuse = slab->objects; > - slab->freelist = NULL; > - } > - return false; > -} > - > -static inline int free_consistency_checks(struct kmem_cache *s, > - struct slab *slab, void *object, unsigned long addr) > -{ > - if (!check_valid_pointer(s, slab, object)) { > - slab_err(s, slab, "Invalid object pointer 0x%p", object); > - return 0; > - } > - > - if (on_freelist(s, slab, object)) { > - object_err(s, slab, object, "Object already free"); > - return 0; > - } > - > - if (!check_object(s, slab, object, SLUB_RED_ACTIVE)) > - return 0; > - > - if (unlikely(s != slab->slab_cache)) { > - if (!folio_test_slab(slab_folio(slab))) { > - slab_err(s, slab, "Attempt to free object(0x%p) outside of slab", > - object); > - } else if (!slab->slab_cache) { > - pr_err("SLUB <none>: no slab for object 0x%p.\n", > - object); > - dump_stack(); > - } else > - object_err(s, slab, object, > - "page slab pointer corrupt."); > - return 0; > - } > - return 1; > -} > - > -/* > - * Parse a block of slub_debug options. Blocks are delimited by ';' > - * > - * @str: start of block > - * @flags: returns parsed flags, or DEBUG_DEFAULT_FLAGS if none specified > - * @slabs: return start of list of slabs, or NULL when there's no list > - * @init: assume this is initial parsing and not per-kmem-create parsing > - * > - * returns the start of next block if there's any, or NULL > - */ > -static char * > -parse_slub_debug_flags(char *str, slab_flags_t *flags, char **slabs, bool init) > -{ > - bool higher_order_disable = false; > - > - /* Skip any completely empty blocks */ > - while (*str && *str == ';') > - str++; > - > - if (*str == ',') { > - /* > - * No options but restriction on slabs. This means full > - * debugging for slabs matching a pattern. > - */ > - *flags = DEBUG_DEFAULT_FLAGS; > - goto check_slabs; > - } > - *flags = 0; > - > - /* Determine which debug features should be switched on */ > - for (; *str && *str != ',' && *str != ';'; str++) { > - switch (tolower(*str)) { > - case '-': > - *flags = 0; > - break; > - case 'f': > - *flags |= SLAB_CONSISTENCY_CHECKS; > - break; > - case 'z': > - *flags |= SLAB_RED_ZONE; > - break; > - case 'p': > - *flags |= SLAB_POISON; > - break; > - case 'u': > - *flags |= SLAB_STORE_USER; > - break; > - case 't': > - *flags |= SLAB_TRACE; > - break; > - case 'a': > - *flags |= SLAB_FAILSLAB; > - break; > - case 'o': > - /* > - * Avoid enabling debugging on caches if its minimum > - * order would increase as a result. > - */ > - higher_order_disable = true; > - break; > - default: > - if (init) > - pr_err("slub_debug option '%c' unknown. skipped\n", *str); > - } > - } > -check_slabs: > - if (*str == ',') > - *slabs = ++str; > - else > - *slabs = NULL; > - > - /* Skip over the slab list */ > - while (*str && *str != ';') > - str++; > - > - /* Skip any completely empty blocks */ > - while (*str && *str == ';') > - str++; > - > - if (init && higher_order_disable) > - disable_higher_order_debug = 1; > - > - if (*str) > - return str; > - else > - return NULL; > -} > - > -static int __init setup_slub_debug(char *str) > -{ > - slab_flags_t flags; > - slab_flags_t global_flags; > - char *saved_str; > - char *slab_list; > - bool global_slub_debug_changed = false; > - bool slab_list_specified = false; > - > - global_flags = DEBUG_DEFAULT_FLAGS; > - if (*str++ != '=' || !*str) > - /* > - * No options specified. Switch on full debugging. > - */ > - goto out; > - > - saved_str = str; > - while (str) { > - str = parse_slub_debug_flags(str, &flags, &slab_list, true); > - > - if (!slab_list) { > - global_flags = flags; > - global_slub_debug_changed = true; > - } else { > - slab_list_specified = true; > - if (flags & SLAB_STORE_USER) > - stack_depot_request_early_init(); > - } > - } > - > - /* > - * For backwards compatibility, a single list of flags with list of > - * slabs means debugging is only changed for those slabs, so the global > - * slub_debug should be unchanged (0 or DEBUG_DEFAULT_FLAGS, depending > - * on CONFIG_SLUB_DEBUG_ON). We can extended that to multiple lists as > - * long as there is no option specifying flags without a slab list. > - */ > - if (slab_list_specified) { > - if (!global_slub_debug_changed) > - global_flags = slub_debug; > - slub_debug_string = saved_str; > - } > -out: > - slub_debug = global_flags; > - if (slub_debug & SLAB_STORE_USER) > - stack_depot_request_early_init(); > - if (slub_debug != 0 || slub_debug_string) > - static_branch_enable(&slub_debug_enabled); > - else > - static_branch_disable(&slub_debug_enabled); > - if ((static_branch_unlikely(&init_on_alloc) || > - static_branch_unlikely(&init_on_free)) && > - (slub_debug & SLAB_POISON)) > - pr_info("mem auto-init: SLAB_POISON will take precedence over init_on_alloc/init_on_free\n"); > - return 1; > -} > - > -__setup("slub_debug", setup_slub_debug); > - > -/* > - * kmem_cache_flags - apply debugging options to the cache > - * @object_size: the size of an object without meta data > - * @flags: flags to set > - * @name: name of the cache > - * > - * Debug option(s) are applied to @flags. In addition to the debug > - * option(s), if a slab name (or multiple) is specified i.e. > - * slub_debug=<Debug-Options>,<slab name1>,<slab name2> ... > - * then only the select slabs will receive the debug option(s). > - */ > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name) > -{ > - char *iter; > - size_t len; > - char *next_block; > - slab_flags_t block_flags; > - slab_flags_t slub_debug_local = slub_debug; > - > - if (flags & SLAB_NO_USER_FLAGS) > - return flags; > - > - /* > - * If the slab cache is for debugging (e.g. kmemleak) then > - * don't store user (stack trace) information by default, > - * but let the user enable it via the command line below. > - */ > - if (flags & SLAB_NOLEAKTRACE) > - slub_debug_local &= ~SLAB_STORE_USER; > - > - len = strlen(name); > - next_block = slub_debug_string; > - /* Go through all blocks of debug options, see if any matches our slab's name */ > - while (next_block) { > - next_block = parse_slub_debug_flags(next_block, &block_flags, &iter, false); > - if (!iter) > - continue; > - /* Found a block that has a slab list, search it */ > - while (*iter) { > - char *end, *glob; > - size_t cmplen; > - > - end = strchrnul(iter, ','); > - if (next_block && next_block < end) > - end = next_block - 1; > - > - glob = strnchr(iter, end - iter, '*'); > - if (glob) > - cmplen = glob - iter; > - else > - cmplen = max_t(size_t, len, (end - iter)); > - > - if (!strncmp(name, iter, cmplen)) { > - flags |= block_flags; > - return flags; > - } > - > - if (!*end || *end == ';') > - break; > - iter = end + 1; > - } > - } > - > - return flags | slub_debug_local; > -} > -#else /* !CONFIG_SLUB_DEBUG */ > -static inline void setup_object_debug(struct kmem_cache *s, void *object) {} > -static inline > -void setup_slab_debug(struct kmem_cache *s, struct slab *slab, void *addr) {} > - > -static inline bool alloc_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *object, int orig_size) { return true; } > - > -static inline bool free_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, int *bulk_cnt, > - unsigned long addr, depot_stack_handle_t handle) { return true; } > - > -static inline void slab_pad_check(struct kmem_cache *s, struct slab *slab) {} > -static inline int check_object(struct kmem_cache *s, struct slab *slab, > - void *object, u8 val) { return 1; } > -static inline depot_stack_handle_t set_track_prepare(void) { return 0; } > -static inline void set_track(struct kmem_cache *s, void *object, > - enum track_item alloc, unsigned long addr) {} > -static inline void add_full(struct kmem_cache *s, struct kmem_cache_node *n, > - struct slab *slab) {} > -static inline void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, > - struct slab *slab) {} > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name) > -{ > - return flags; > -} > -#define slub_debug 0 > - > -#define disable_higher_order_debug 0 > - > -static inline unsigned long slabs_node(struct kmem_cache *s, int node) > - { return 0; } > -static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) > - { return 0; } > -static inline void inc_slabs_node(struct kmem_cache *s, int node, > - int objects) {} > -static inline void dec_slabs_node(struct kmem_cache *s, int node, > - int objects) {} > - > -#ifndef CONFIG_SLUB_TINY > -static bool freelist_corrupted(struct kmem_cache *s, struct slab *slab, > - void **freelist, void *nextfree) > -{ > - return false; > -} > -#endif > -#endif /* CONFIG_SLUB_DEBUG */ > - > -/* > - * Hooks for other subsystems that check memory allocations. In a typical > - * production configuration these hooks all should produce no code at all. > - */ > -static __always_inline bool slab_free_hook(struct kmem_cache *s, > - void *x, bool init) > -{ > - kmemleak_free_recursive(x, s->flags); > - kmsan_slab_free(s, x); > - > - debug_check_no_locks_freed(x, s->object_size); > - > - if (!(s->flags & SLAB_DEBUG_OBJECTS)) > - debug_check_no_obj_freed(x, s->object_size); > - > - /* Use KCSAN to help debug racy use-after-free. */ > - if (!(s->flags & SLAB_TYPESAFE_BY_RCU)) > - __kcsan_check_access(x, s->object_size, > - KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ASSERT); > - > - /* > - * As memory initialization might be integrated into KASAN, > - * kasan_slab_free and initialization memset's must be > - * kept together to avoid discrepancies in behavior. > - * > - * The initialization memset's clear the object and the metadata, > - * but don't touch the SLAB redzone. > - */ > - if (init) { > - int rsize; > - > - if (!kasan_has_integrated_init()) > - memset(kasan_reset_tag(x), 0, s->object_size); > - rsize = (s->flags & SLAB_RED_ZONE) ? s->red_left_pad : 0; > - memset((char *)kasan_reset_tag(x) + s->inuse, 0, > - s->size - s->inuse - rsize); > - } > - /* KASAN might put x into memory quarantine, delaying its reuse. */ > - return kasan_slab_free(s, x, init); > -} > - > -static inline bool slab_free_freelist_hook(struct kmem_cache *s, > - void **head, void **tail, > - int *cnt) > -{ > - > - void *object; > - void *next = *head; > - void *old_tail = *tail ? *tail : *head; > - > - if (is_kfence_address(next)) { > - slab_free_hook(s, next, false); > - return true; > - } > - > - /* Head and tail of the reconstructed freelist */ > - *head = NULL; > - *tail = NULL; > - > - do { > - object = next; > - next = get_freepointer(s, object); > - > - /* If object's reuse doesn't have to be delayed */ > - if (!slab_free_hook(s, object, slab_want_init_on_free(s))) { > - /* Move object to the new freelist */ > - set_freepointer(s, object, *head); > - *head = object; > - if (!*tail) > - *tail = object; > - } else { > - /* > - * Adjust the reconstructed freelist depth > - * accordingly if object's reuse is delayed. > - */ > - --(*cnt); > - } > - } while (object != old_tail); > - > - if (*head == *tail) > - *tail = NULL; > - > - return *head != NULL; > -} > - > -static void *setup_object(struct kmem_cache *s, void *object) > -{ > - setup_object_debug(s, object); > - object = kasan_init_slab_obj(s, object); > - if (unlikely(s->ctor)) { > - kasan_unpoison_object_data(s, object); > - s->ctor(object); > - kasan_poison_object_data(s, object); > - } > - return object; > -} > - > -/* > - * Slab allocation and freeing > - */ > -static inline struct slab *alloc_slab_page(gfp_t flags, int node, > - struct kmem_cache_order_objects oo) > -{ > - struct folio *folio; > - struct slab *slab; > - unsigned int order = oo_order(oo); > - > - if (node == NUMA_NO_NODE) > - folio = (struct folio *)alloc_pages(flags, order); > - else > - folio = (struct folio *)__alloc_pages_node(node, flags, order); > - > - if (!folio) > - return NULL; > - > - slab = folio_slab(folio); > - __folio_set_slab(folio); > - /* Make the flag visible before any changes to folio->mapping */ > - smp_wmb(); > - if (folio_is_pfmemalloc(folio)) > - slab_set_pfmemalloc(slab); > - > - return slab; > -} > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -/* Pre-initialize the random sequence cache */ > -static int init_cache_random_seq(struct kmem_cache *s) > -{ > - unsigned int count = oo_objects(s->oo); > - int err; > - > - /* Bailout if already initialised */ > - if (s->random_seq) > - return 0; > - > - err = cache_random_seq_create(s, count, GFP_KERNEL); > - if (err) { > - pr_err("SLUB: Unable to initialize free list for %s\n", > - s->name); > - return err; > - } > - > - /* Transform to an offset on the set of pages */ > - if (s->random_seq) { > - unsigned int i; > - > - for (i = 0; i < count; i++) > - s->random_seq[i] *= s->size; > - } > - return 0; > -} > - > -/* Initialize each random sequence freelist per cache */ > -static void __init init_freelist_randomization(void) > -{ > - struct kmem_cache *s; > - > - mutex_lock(&slab_mutex); > - > - list_for_each_entry(s, &slab_caches, list) > - init_cache_random_seq(s); > - > - mutex_unlock(&slab_mutex); > -} > - > -/* Get the next entry on the pre-computed freelist randomized */ > -static void *next_freelist_entry(struct kmem_cache *s, struct slab *slab, > - unsigned long *pos, void *start, > - unsigned long page_limit, > - unsigned long freelist_count) > -{ > - unsigned int idx; > - > - /* > - * If the target page allocation failed, the number of objects on the > - * page might be smaller than the usual size defined by the cache. > - */ > - do { > - idx = s->random_seq[*pos]; > - *pos += 1; > - if (*pos >= freelist_count) > - *pos = 0; > - } while (unlikely(idx >= page_limit)); > - > - return (char *)start + idx; > -} > - > -/* Shuffle the single linked freelist based on a random pre-computed sequence */ > -static bool shuffle_freelist(struct kmem_cache *s, struct slab *slab) > -{ > - void *start; > - void *cur; > - void *next; > - unsigned long idx, pos, page_limit, freelist_count; > - > - if (slab->objects < 2 || !s->random_seq) > - return false; > - > - freelist_count = oo_objects(s->oo); > - pos = get_random_u32_below(freelist_count); > - > - page_limit = slab->objects * s->size; > - start = fixup_red_left(s, slab_address(slab)); > - > - /* First entry is used as the base of the freelist */ > - cur = next_freelist_entry(s, slab, &pos, start, page_limit, > - freelist_count); > - cur = setup_object(s, cur); > - slab->freelist = cur; > - > - for (idx = 1; idx < slab->objects; idx++) { > - next = next_freelist_entry(s, slab, &pos, start, page_limit, > - freelist_count); > - next = setup_object(s, next); > - set_freepointer(s, cur, next); > - cur = next; > - } > - set_freepointer(s, cur, NULL); > - > - return true; > -} > -#else > -static inline int init_cache_random_seq(struct kmem_cache *s) > -{ > - return 0; > -} > -static inline void init_freelist_randomization(void) { } > -static inline bool shuffle_freelist(struct kmem_cache *s, struct slab *slab) > -{ > - return false; > -} > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > - > -static struct slab *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) > -{ > - struct slab *slab; > - struct kmem_cache_order_objects oo = s->oo; > - gfp_t alloc_gfp; > - void *start, *p, *next; > - int idx; > - bool shuffle; > - > - flags &= gfp_allowed_mask; > - > - flags |= s->allocflags; > - > - /* > - * Let the initial higher-order allocation fail under memory pressure > - * so we fall-back to the minimum order allocation. > - */ > - alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL; > - if ((alloc_gfp & __GFP_DIRECT_RECLAIM) && oo_order(oo) > oo_order(s->min)) > - alloc_gfp = (alloc_gfp | __GFP_NOMEMALLOC) & ~__GFP_RECLAIM; > - > - slab = alloc_slab_page(alloc_gfp, node, oo); > - if (unlikely(!slab)) { > - oo = s->min; > - alloc_gfp = flags; > - /* > - * Allocation may have failed due to fragmentation. > - * Try a lower order alloc if possible > - */ > - slab = alloc_slab_page(alloc_gfp, node, oo); > - if (unlikely(!slab)) > - return NULL; > - stat(s, ORDER_FALLBACK); > - } > - > - slab->objects = oo_objects(oo); > - slab->inuse = 0; > - slab->frozen = 0; > - > - account_slab(slab, oo_order(oo), s, flags); > - > - slab->slab_cache = s; > - > - kasan_poison_slab(slab); > - > - start = slab_address(slab); > - > - setup_slab_debug(s, slab, start); > - > - shuffle = shuffle_freelist(s, slab); > - > - if (!shuffle) { > - start = fixup_red_left(s, start); > - start = setup_object(s, start); > - slab->freelist = start; > - for (idx = 0, p = start; idx < slab->objects - 1; idx++) { > - next = p + s->size; > - next = setup_object(s, next); > - set_freepointer(s, p, next); > - p = next; > - } > - set_freepointer(s, p, NULL); > - } > - > - return slab; > -} > - > -static struct slab *new_slab(struct kmem_cache *s, gfp_t flags, int node) > -{ > - if (unlikely(flags & GFP_SLAB_BUG_MASK)) > - flags = kmalloc_fix_flags(flags); > - > - WARN_ON_ONCE(s->ctor && (flags & __GFP_ZERO)); > - > - return allocate_slab(s, > - flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node); > -} > - > -static void __free_slab(struct kmem_cache *s, struct slab *slab) > -{ > - struct folio *folio = slab_folio(slab); > - int order = folio_order(folio); > - int pages = 1 << order; > - > - __slab_clear_pfmemalloc(slab); > - folio->mapping = NULL; > - /* Make the mapping reset visible before clearing the flag */ > - smp_wmb(); > - __folio_clear_slab(folio); > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += pages; > - unaccount_slab(slab, order, s); > - __free_pages(&folio->page, order); > -} > - > -static void rcu_free_slab(struct rcu_head *h) > -{ > - struct slab *slab = container_of(h, struct slab, rcu_head); > - > - __free_slab(slab->slab_cache, slab); > -} > - > -static void free_slab(struct kmem_cache *s, struct slab *slab) > -{ > - if (kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) { > - void *p; > - > - slab_pad_check(s, slab); > - for_each_object(p, s, slab_address(slab), slab->objects) > - check_object(s, slab, p, SLUB_RED_INACTIVE); > - } > - > - if (unlikely(s->flags & SLAB_TYPESAFE_BY_RCU)) > - call_rcu(&slab->rcu_head, rcu_free_slab); > - else > - __free_slab(s, slab); > -} > - > -static void discard_slab(struct kmem_cache *s, struct slab *slab) > -{ > - dec_slabs_node(s, slab_nid(slab), slab->objects); > - free_slab(s, slab); > -} > - > -/* > - * Management of partially allocated slabs. > - */ > -static inline void > -__add_partial(struct kmem_cache_node *n, struct slab *slab, int tail) > -{ > - n->nr_partial++; > - if (tail == DEACTIVATE_TO_TAIL) > - list_add_tail(&slab->slab_list, &n->partial); > - else > - list_add(&slab->slab_list, &n->partial); > -} > - > -static inline void add_partial(struct kmem_cache_node *n, > - struct slab *slab, int tail) > -{ > - lockdep_assert_held(&n->list_lock); > - __add_partial(n, slab, tail); > -} > - > -static inline void remove_partial(struct kmem_cache_node *n, > - struct slab *slab) > -{ > - lockdep_assert_held(&n->list_lock); > - list_del(&slab->slab_list); > - n->nr_partial--; > -} > - > -/* > - * Called only for kmem_cache_debug() caches instead of acquire_slab(), with a > - * slab from the n->partial list. Remove only a single object from the slab, do > - * the alloc_debug_processing() checks and leave the slab on the list, or move > - * it to full list if it was the last free object. > - */ > -static void *alloc_single_from_partial(struct kmem_cache *s, > - struct kmem_cache_node *n, struct slab *slab, int orig_size) > -{ > - void *object; > - > - lockdep_assert_held(&n->list_lock); > - > - object = slab->freelist; > - slab->freelist = get_freepointer(s, object); > - slab->inuse++; > - > - if (!alloc_debug_processing(s, slab, object, orig_size)) { > - remove_partial(n, slab); > - return NULL; > - } > - > - if (slab->inuse == slab->objects) { > - remove_partial(n, slab); > - add_full(s, n, slab); > - } > - > - return object; > -} > - > -/* > - * Called only for kmem_cache_debug() caches to allocate from a freshly > - * allocated slab. Allocate a single object instead of whole freelist > - * and put the slab to the partial (or full) list. > - */ > -static void *alloc_single_from_new_slab(struct kmem_cache *s, > - struct slab *slab, int orig_size) > -{ > - int nid = slab_nid(slab); > - struct kmem_cache_node *n = get_node(s, nid); > - unsigned long flags; > - void *object; > - > - > - object = slab->freelist; > - slab->freelist = get_freepointer(s, object); > - slab->inuse = 1; > - > - if (!alloc_debug_processing(s, slab, object, orig_size)) > - /* > - * It's not really expected that this would fail on a > - * freshly allocated slab, but a concurrent memory > - * corruption in theory could cause that. > - */ > - return NULL; > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - if (slab->inuse == slab->objects) > - add_full(s, n, slab); > - else > - add_partial(n, slab, DEACTIVATE_TO_HEAD); > - > - inc_slabs_node(s, nid, slab->objects); > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - return object; > -} > - > -/* > - * Remove slab from the partial list, freeze it and > - * return the pointer to the freelist. > - * > - * Returns a list of objects or NULL if it fails. > - */ > -static inline void *acquire_slab(struct kmem_cache *s, > - struct kmem_cache_node *n, struct slab *slab, > - int mode) > -{ > - void *freelist; > - unsigned long counters; > - struct slab new; > - > - lockdep_assert_held(&n->list_lock); > - > - /* > - * Zap the freelist and set the frozen bit. > - * The old freelist is the list of objects for the > - * per cpu allocation list. > - */ > - freelist = slab->freelist; > - counters = slab->counters; > - new.counters = counters; > - if (mode) { > - new.inuse = slab->objects; > - new.freelist = NULL; > - } else { > - new.freelist = freelist; > - } > - > - VM_BUG_ON(new.frozen); > - new.frozen = 1; > - > - if (!__cmpxchg_double_slab(s, slab, > - freelist, counters, > - new.freelist, new.counters, > - "acquire_slab")) > - return NULL; > - > - remove_partial(n, slab); > - WARN_ON(!freelist); > - return freelist; > -} > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -static void put_cpu_partial(struct kmem_cache *s, struct slab *slab, int drain); > -#else > -static inline void put_cpu_partial(struct kmem_cache *s, struct slab *slab, > - int drain) { } > -#endif > -static inline bool pfmemalloc_match(struct slab *slab, gfp_t gfpflags); > - > -/* > - * Try to allocate a partial slab from a specific node. > - */ > -static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n, > - struct partial_context *pc) > -{ > - struct slab *slab, *slab2; > - void *object = NULL; > - unsigned long flags; > - unsigned int partial_slabs = 0; > - > - /* > - * Racy check. If we mistakenly see no partial slabs then we > - * just allocate an empty slab. If we mistakenly try to get a > - * partial slab and there is none available then get_partial() > - * will return NULL. > - */ > - if (!n || !n->nr_partial) > - return NULL; > - > - spin_lock_irqsave(&n->list_lock, flags); > - list_for_each_entry_safe(slab, slab2, &n->partial, slab_list) { > - void *t; > - > - if (!pfmemalloc_match(slab, pc->flags)) > - continue; > - > - if (IS_ENABLED(CONFIG_SLUB_TINY) || kmem_cache_debug(s)) { > - object = alloc_single_from_partial(s, n, slab, > - pc->orig_size); > - if (object) > - break; > - continue; > - } > - > - t = acquire_slab(s, n, slab, object == NULL); > - if (!t) > - break; > - > - if (!object) { > - *pc->slab = slab; > - stat(s, ALLOC_FROM_PARTIAL); > - object = t; > - } else { > - put_cpu_partial(s, slab, 0); > - stat(s, CPU_PARTIAL_NODE); > - partial_slabs++; > - } > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - if (!kmem_cache_has_cpu_partial(s) > - || partial_slabs > s->cpu_partial_slabs / 2) > - break; > -#else > - break; > -#endif > - > - } > - spin_unlock_irqrestore(&n->list_lock, flags); > - return object; > -} > - > -/* > - * Get a slab from somewhere. Search in increasing NUMA distances. > - */ > -static void *get_any_partial(struct kmem_cache *s, struct partial_context *pc) > -{ > -#ifdef CONFIG_NUMA > - struct zonelist *zonelist; > - struct zoneref *z; > - struct zone *zone; > - enum zone_type highest_zoneidx = gfp_zone(pc->flags); > - void *object; > - unsigned int cpuset_mems_cookie; > - > - /* > - * The defrag ratio allows a configuration of the tradeoffs between > - * inter node defragmentation and node local allocations. A lower > - * defrag_ratio increases the tendency to do local allocations > - * instead of attempting to obtain partial slabs from other nodes. > - * > - * If the defrag_ratio is set to 0 then kmalloc() always > - * returns node local objects. If the ratio is higher then kmalloc() > - * may return off node objects because partial slabs are obtained > - * from other nodes and filled up. > - * > - * If /sys/kernel/slab/xx/remote_node_defrag_ratio is set to 100 > - * (which makes defrag_ratio = 1000) then every (well almost) > - * allocation will first attempt to defrag slab caches on other nodes. > - * This means scanning over all nodes to look for partial slabs which > - * may be expensive if we do it every time we are trying to find a slab > - * with available objects. > - */ > - if (!s->remote_node_defrag_ratio || > - get_cycles() % 1024 > s->remote_node_defrag_ratio) > - return NULL; > - > - do { > - cpuset_mems_cookie = read_mems_allowed_begin(); > - zonelist = node_zonelist(mempolicy_slab_node(), pc->flags); > - for_each_zone_zonelist(zone, z, zonelist, highest_zoneidx) { > - struct kmem_cache_node *n; > - > - n = get_node(s, zone_to_nid(zone)); > - > - if (n && cpuset_zone_allowed(zone, pc->flags) && > - n->nr_partial > s->min_partial) { > - object = get_partial_node(s, n, pc); > - if (object) { > - /* > - * Don't check read_mems_allowed_retry() > - * here - if mems_allowed was updated in > - * parallel, that was a harmless race > - * between allocation and the cpuset > - * update > - */ > - return object; > - } > - } > - } > - } while (read_mems_allowed_retry(cpuset_mems_cookie)); > -#endif /* CONFIG_NUMA */ > - return NULL; > -} > - > -/* > - * Get a partial slab, lock it and return it. > - */ > -static void *get_partial(struct kmem_cache *s, int node, struct partial_context *pc) > -{ > - void *object; > - int searchnode = node; > - > - if (node == NUMA_NO_NODE) > - searchnode = numa_mem_id(); > - > - object = get_partial_node(s, get_node(s, searchnode), pc); > - if (object || node != NUMA_NO_NODE) > - return object; > - > - return get_any_partial(s, pc); > -} > - > -#ifndef CONFIG_SLUB_TINY > - > -#ifdef CONFIG_PREEMPTION > -/* > - * Calculate the next globally unique transaction for disambiguation > - * during cmpxchg. The transactions start with the cpu number and are then > - * incremented by CONFIG_NR_CPUS. > - */ > -#define TID_STEP roundup_pow_of_two(CONFIG_NR_CPUS) > -#else > -/* > - * No preemption supported therefore also no need to check for > - * different cpus. > - */ > -#define TID_STEP 1 > -#endif /* CONFIG_PREEMPTION */ > - > -static inline unsigned long next_tid(unsigned long tid) > -{ > - return tid + TID_STEP; > -} > - > -#ifdef SLUB_DEBUG_CMPXCHG > -static inline unsigned int tid_to_cpu(unsigned long tid) > -{ > - return tid % TID_STEP; > -} > - > -static inline unsigned long tid_to_event(unsigned long tid) > -{ > - return tid / TID_STEP; > -} > -#endif > - > -static inline unsigned int init_tid(int cpu) > -{ > - return cpu; > -} > - > -static inline void note_cmpxchg_failure(const char *n, > - const struct kmem_cache *s, unsigned long tid) > -{ > -#ifdef SLUB_DEBUG_CMPXCHG > - unsigned long actual_tid = __this_cpu_read(s->cpu_slab->tid); > - > - pr_info("%s %s: cmpxchg redo ", n, s->name); > - > -#ifdef CONFIG_PREEMPTION > - if (tid_to_cpu(tid) != tid_to_cpu(actual_tid)) > - pr_warn("due to cpu change %d -> %d\n", > - tid_to_cpu(tid), tid_to_cpu(actual_tid)); > - else > -#endif > - if (tid_to_event(tid) != tid_to_event(actual_tid)) > - pr_warn("due to cpu running other code. Event %ld->%ld\n", > - tid_to_event(tid), tid_to_event(actual_tid)); > - else > - pr_warn("for unknown reason: actual=%lx was=%lx target=%lx\n", > - actual_tid, tid, next_tid(tid)); > -#endif > - stat(s, CMPXCHG_DOUBLE_CPU_FAIL); > -} > - > -static void init_kmem_cache_cpus(struct kmem_cache *s) > -{ > - int cpu; > - struct kmem_cache_cpu *c; > - > - for_each_possible_cpu(cpu) { > - c = per_cpu_ptr(s->cpu_slab, cpu); > - local_lock_init(&c->lock); > - c->tid = init_tid(cpu); > - } > -} > - > -/* > - * Finishes removing the cpu slab. Merges cpu's freelist with slab's freelist, > - * unfreezes the slabs and puts it on the proper list. > - * Assumes the slab has been already safely taken away from kmem_cache_cpu > - * by the caller. > - */ > -static void deactivate_slab(struct kmem_cache *s, struct slab *slab, > - void *freelist) > -{ > - enum slab_modes { M_NONE, M_PARTIAL, M_FREE, M_FULL_NOLIST }; > - struct kmem_cache_node *n = get_node(s, slab_nid(slab)); > - int free_delta = 0; > - enum slab_modes mode = M_NONE; > - void *nextfree, *freelist_iter, *freelist_tail; > - int tail = DEACTIVATE_TO_HEAD; > - unsigned long flags = 0; > - struct slab new; > - struct slab old; > - > - if (slab->freelist) { > - stat(s, DEACTIVATE_REMOTE_FREES); > - tail = DEACTIVATE_TO_TAIL; > - } > - > - /* > - * Stage one: Count the objects on cpu's freelist as free_delta and > - * remember the last object in freelist_tail for later splicing. > - */ > - freelist_tail = NULL; > - freelist_iter = freelist; > - while (freelist_iter) { > - nextfree = get_freepointer(s, freelist_iter); > - > - /* > - * If 'nextfree' is invalid, it is possible that the object at > - * 'freelist_iter' is already corrupted. So isolate all objects > - * starting at 'freelist_iter' by skipping them. > - */ > - if (freelist_corrupted(s, slab, &freelist_iter, nextfree)) > - break; > - > - freelist_tail = freelist_iter; > - free_delta++; > - > - freelist_iter = nextfree; > - } > - > - /* > - * Stage two: Unfreeze the slab while splicing the per-cpu > - * freelist to the head of slab's freelist. > - * > - * Ensure that the slab is unfrozen while the list presence > - * reflects the actual number of objects during unfreeze. > - * > - * We first perform cmpxchg holding lock and insert to list > - * when it succeed. If there is mismatch then the slab is not > - * unfrozen and number of objects in the slab may have changed. > - * Then release lock and retry cmpxchg again. > - */ > -redo: > - > - old.freelist = READ_ONCE(slab->freelist); > - old.counters = READ_ONCE(slab->counters); > - VM_BUG_ON(!old.frozen); > - > - /* Determine target state of the slab */ > - new.counters = old.counters; > - if (freelist_tail) { > - new.inuse -= free_delta; > - set_freepointer(s, freelist_tail, old.freelist); > - new.freelist = freelist; > - } else > - new.freelist = old.freelist; > - > - new.frozen = 0; > - > - if (!new.inuse && n->nr_partial >= s->min_partial) { > - mode = M_FREE; > - } else if (new.freelist) { > - mode = M_PARTIAL; > - /* > - * Taking the spinlock removes the possibility that > - * acquire_slab() will see a slab that is frozen > - */ > - spin_lock_irqsave(&n->list_lock, flags); > - } else { > - mode = M_FULL_NOLIST; > - } > - > - > - if (!cmpxchg_double_slab(s, slab, > - old.freelist, old.counters, > - new.freelist, new.counters, > - "unfreezing slab")) { > - if (mode == M_PARTIAL) > - spin_unlock_irqrestore(&n->list_lock, flags); > - goto redo; > - } > - > - > - if (mode == M_PARTIAL) { > - add_partial(n, slab, tail); > - spin_unlock_irqrestore(&n->list_lock, flags); > - stat(s, tail); > - } else if (mode == M_FREE) { > - stat(s, DEACTIVATE_EMPTY); > - discard_slab(s, slab); > - stat(s, FREE_SLAB); > - } else if (mode == M_FULL_NOLIST) { > - stat(s, DEACTIVATE_FULL); > - } > -} > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -static void __unfreeze_partials(struct kmem_cache *s, struct slab *partial_slab) > -{ > - struct kmem_cache_node *n = NULL, *n2 = NULL; > - struct slab *slab, *slab_to_discard = NULL; > - unsigned long flags = 0; > - > - while (partial_slab) { > - struct slab new; > - struct slab old; > - > - slab = partial_slab; > - partial_slab = slab->next; > - > - n2 = get_node(s, slab_nid(slab)); > - if (n != n2) { > - if (n) > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - n = n2; > - spin_lock_irqsave(&n->list_lock, flags); > - } > - > - do { > - > - old.freelist = slab->freelist; > - old.counters = slab->counters; > - VM_BUG_ON(!old.frozen); > - > - new.counters = old.counters; > - new.freelist = old.freelist; > - > - new.frozen = 0; > - > - } while (!__cmpxchg_double_slab(s, slab, > - old.freelist, old.counters, > - new.freelist, new.counters, > - "unfreezing slab")); > - > - if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) { > - slab->next = slab_to_discard; > - slab_to_discard = slab; > - } else { > - add_partial(n, slab, DEACTIVATE_TO_TAIL); > - stat(s, FREE_ADD_PARTIAL); > - } > - } > - > - if (n) > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - while (slab_to_discard) { > - slab = slab_to_discard; > - slab_to_discard = slab_to_discard->next; > - > - stat(s, DEACTIVATE_EMPTY); > - discard_slab(s, slab); > - stat(s, FREE_SLAB); > - } > -} > - > -/* > - * Unfreeze all the cpu partial slabs. > - */ > -static void unfreeze_partials(struct kmem_cache *s) > -{ > - struct slab *partial_slab; > - unsigned long flags; > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - partial_slab = this_cpu_read(s->cpu_slab->partial); > - this_cpu_write(s->cpu_slab->partial, NULL); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - if (partial_slab) > - __unfreeze_partials(s, partial_slab); > -} > - > -static void unfreeze_partials_cpu(struct kmem_cache *s, > - struct kmem_cache_cpu *c) > -{ > - struct slab *partial_slab; > - > - partial_slab = slub_percpu_partial(c); > - c->partial = NULL; > - > - if (partial_slab) > - __unfreeze_partials(s, partial_slab); > -} > - > -/* > - * Put a slab that was just frozen (in __slab_free|get_partial_node) into a > - * partial slab slot if available. > - * > - * If we did not find a slot then simply move all the partials to the > - * per node partial list. > - */ > -static void put_cpu_partial(struct kmem_cache *s, struct slab *slab, int drain) > -{ > - struct slab *oldslab; > - struct slab *slab_to_unfreeze = NULL; > - unsigned long flags; > - int slabs = 0; > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - > - oldslab = this_cpu_read(s->cpu_slab->partial); > - > - if (oldslab) { > - if (drain && oldslab->slabs >= s->cpu_partial_slabs) { > - /* > - * Partial array is full. Move the existing set to the > - * per node partial list. Postpone the actual unfreezing > - * outside of the critical section. > - */ > - slab_to_unfreeze = oldslab; > - oldslab = NULL; > - } else { > - slabs = oldslab->slabs; > - } > - } > - > - slabs++; > - > - slab->slabs = slabs; > - slab->next = oldslab; > - > - this_cpu_write(s->cpu_slab->partial, slab); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - if (slab_to_unfreeze) { > - __unfreeze_partials(s, slab_to_unfreeze); > - stat(s, CPU_PARTIAL_DRAIN); > - } > -} > - > -#else /* CONFIG_SLUB_CPU_PARTIAL */ > - > -static inline void unfreeze_partials(struct kmem_cache *s) { } > -static inline void unfreeze_partials_cpu(struct kmem_cache *s, > - struct kmem_cache_cpu *c) { } > - > -#endif /* CONFIG_SLUB_CPU_PARTIAL */ > - > -static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) > -{ > - unsigned long flags; > - struct slab *slab; > - void *freelist; > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - > - slab = c->slab; > - freelist = c->freelist; > - > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - if (slab) { > - deactivate_slab(s, slab, freelist); > - stat(s, CPUSLAB_FLUSH); > - } > -} > - > -static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) > -{ > - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); > - void *freelist = c->freelist; > - struct slab *slab = c->slab; > - > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - > - if (slab) { > - deactivate_slab(s, slab, freelist); > - stat(s, CPUSLAB_FLUSH); > - } > - > - unfreeze_partials_cpu(s, c); > -} > - > -struct slub_flush_work { > - struct work_struct work; > - struct kmem_cache *s; > - bool skip; > -}; > - > -/* > - * Flush cpu slab. > - * > - * Called from CPU work handler with migration disabled. > - */ > -static void flush_cpu_slab(struct work_struct *w) > -{ > - struct kmem_cache *s; > - struct kmem_cache_cpu *c; > - struct slub_flush_work *sfw; > - > - sfw = container_of(w, struct slub_flush_work, work); > - > - s = sfw->s; > - c = this_cpu_ptr(s->cpu_slab); > - > - if (c->slab) > - flush_slab(s, c); > - > - unfreeze_partials(s); > -} > - > -static bool has_cpu_slab(int cpu, struct kmem_cache *s) > -{ > - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); > - > - return c->slab || slub_percpu_partial(c); > -} > - > -static DEFINE_MUTEX(flush_lock); > -static DEFINE_PER_CPU(struct slub_flush_work, slub_flush); > - > -static void flush_all_cpus_locked(struct kmem_cache *s) > -{ > - struct slub_flush_work *sfw; > - unsigned int cpu; > - > - lockdep_assert_cpus_held(); > - mutex_lock(&flush_lock); > - > - for_each_online_cpu(cpu) { > - sfw = &per_cpu(slub_flush, cpu); > - if (!has_cpu_slab(cpu, s)) { > - sfw->skip = true; > - continue; > - } > - INIT_WORK(&sfw->work, flush_cpu_slab); > - sfw->skip = false; > - sfw->s = s; > - queue_work_on(cpu, flushwq, &sfw->work); > - } > - > - for_each_online_cpu(cpu) { > - sfw = &per_cpu(slub_flush, cpu); > - if (sfw->skip) > - continue; > - flush_work(&sfw->work); > - } > - > - mutex_unlock(&flush_lock); > -} > - > -static void flush_all(struct kmem_cache *s) > -{ > - cpus_read_lock(); > - flush_all_cpus_locked(s); > - cpus_read_unlock(); > -} > - > -/* > - * Use the cpu notifier to insure that the cpu slabs are flushed when > - * necessary. > - */ > -static int slub_cpu_dead(unsigned int cpu) > -{ > - struct kmem_cache *s; > - > - mutex_lock(&slab_mutex); > - list_for_each_entry(s, &slab_caches, list) > - __flush_cpu_slab(s, cpu); > - mutex_unlock(&slab_mutex); > - return 0; > -} > - > -#else /* CONFIG_SLUB_TINY */ > -static inline void flush_all_cpus_locked(struct kmem_cache *s) { } > -static inline void flush_all(struct kmem_cache *s) { } > -static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) { } > -static inline int slub_cpu_dead(unsigned int cpu) { return 0; } > -#endif /* CONFIG_SLUB_TINY */ > - > -/* > - * Check if the objects in a per cpu structure fit numa > - * locality expectations. > - */ > -static inline int node_match(struct slab *slab, int node) > -{ > -#ifdef CONFIG_NUMA > - if (node != NUMA_NO_NODE && slab_nid(slab) != node) > - return 0; > -#endif > - return 1; > -} > - > -#ifdef CONFIG_SLUB_DEBUG > -static int count_free(struct slab *slab) > -{ > - return slab->objects - slab->inuse; > -} > - > -static inline unsigned long node_nr_objs(struct kmem_cache_node *n) > -{ > - return atomic_long_read(&n->total_objects); > -} > - > -/* Supports checking bulk free of a constructed freelist */ > -static inline bool free_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, int *bulk_cnt, > - unsigned long addr, depot_stack_handle_t handle) > -{ > - bool checks_ok = false; > - void *object = head; > - int cnt = 0; > - > - if (s->flags & SLAB_CONSISTENCY_CHECKS) { > - if (!check_slab(s, slab)) > - goto out; > - } > - > - if (slab->inuse < *bulk_cnt) { > - slab_err(s, slab, "Slab has %d allocated objects but %d are to be freed\n", > - slab->inuse, *bulk_cnt); > - goto out; > - } > - > -next_object: > - > - if (++cnt > *bulk_cnt) > - goto out_cnt; > - > - if (s->flags & SLAB_CONSISTENCY_CHECKS) { > - if (!free_consistency_checks(s, slab, object, addr)) > - goto out; > - } > - > - if (s->flags & SLAB_STORE_USER) > - set_track_update(s, object, TRACK_FREE, addr, handle); > - trace(s, slab, object, 0); > - /* Freepointer not overwritten by init_object(), SLAB_POISON moved it */ > - init_object(s, object, SLUB_RED_INACTIVE); > - > - /* Reached end of constructed freelist yet? */ > - if (object != tail) { > - object = get_freepointer(s, object); > - goto next_object; > - } > - checks_ok = true; > - > -out_cnt: > - if (cnt != *bulk_cnt) { > - slab_err(s, slab, "Bulk free expected %d objects but found %d\n", > - *bulk_cnt, cnt); > - *bulk_cnt = cnt; > - } > - > -out: > - > - if (!checks_ok) > - slab_fix(s, "Object at 0x%p not freed", object); > - > - return checks_ok; > -} > -#endif /* CONFIG_SLUB_DEBUG */ > - > -#if defined(CONFIG_SLUB_DEBUG) || defined(SLAB_SUPPORTS_SYSFS) > -static unsigned long count_partial(struct kmem_cache_node *n, > - int (*get_count)(struct slab *)) > -{ > - unsigned long flags; > - unsigned long x = 0; > - struct slab *slab; > - > - spin_lock_irqsave(&n->list_lock, flags); > - list_for_each_entry(slab, &n->partial, slab_list) > - x += get_count(slab); > - spin_unlock_irqrestore(&n->list_lock, flags); > - return x; > -} > -#endif /* CONFIG_SLUB_DEBUG || SLAB_SUPPORTS_SYSFS */ > - > -#ifdef CONFIG_SLUB_DEBUG > -static noinline void > -slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) > -{ > - static DEFINE_RATELIMIT_STATE(slub_oom_rs, DEFAULT_RATELIMIT_INTERVAL, > - DEFAULT_RATELIMIT_BURST); > - int node; > - struct kmem_cache_node *n; > - > - if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slub_oom_rs)) > - return; > - > - pr_warn("SLUB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", > - nid, gfpflags, &gfpflags); > - pr_warn(" cache: %s, object size: %u, buffer size: %u, default order: %u, min order: %u\n", > - s->name, s->object_size, s->size, oo_order(s->oo), > - oo_order(s->min)); > - > - if (oo_order(s->min) > get_order(s->object_size)) > - pr_warn(" %s debugging increased min order, use slub_debug=O to disable.\n", > - s->name); > - > - for_each_kmem_cache_node(s, node, n) { > - unsigned long nr_slabs; > - unsigned long nr_objs; > - unsigned long nr_free; > - > - nr_free = count_partial(n, count_free); > - nr_slabs = node_nr_slabs(n); > - nr_objs = node_nr_objs(n); > - > - pr_warn(" node %d: slabs: %ld, objs: %ld, free: %ld\n", > - node, nr_slabs, nr_objs, nr_free); > - } > -} > -#else /* CONFIG_SLUB_DEBUG */ > -static inline void > -slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) { } > -#endif > - > -static inline bool pfmemalloc_match(struct slab *slab, gfp_t gfpflags) > -{ > - if (unlikely(slab_test_pfmemalloc(slab))) > - return gfp_pfmemalloc_allowed(gfpflags); > - > - return true; > -} > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Check the slab->freelist and either transfer the freelist to the > - * per cpu freelist or deactivate the slab. > - * > - * The slab is still frozen if the return value is not NULL. > - * > - * If this function returns NULL then the slab has been unfrozen. > - */ > -static inline void *get_freelist(struct kmem_cache *s, struct slab *slab) > -{ > - struct slab new; > - unsigned long counters; > - void *freelist; > - > - lockdep_assert_held(this_cpu_ptr(&s->cpu_slab->lock)); > - > - do { > - freelist = slab->freelist; > - counters = slab->counters; > - > - new.counters = counters; > - VM_BUG_ON(!new.frozen); > - > - new.inuse = slab->objects; > - new.frozen = freelist != NULL; > - > - } while (!__cmpxchg_double_slab(s, slab, > - freelist, counters, > - NULL, new.counters, > - "get_freelist")); > - > - return freelist; > -} > - > -/* > - * Slow path. The lockless freelist is empty or we need to perform > - * debugging duties. > - * > - * Processing is still very fast if new objects have been freed to the > - * regular freelist. In that case we simply take over the regular freelist > - * as the lockless freelist and zap the regular freelist. > - * > - * If that is not working then we fall back to the partial lists. We take the > - * first element of the freelist as the object to allocate now and move the > - * rest of the freelist to the lockless freelist. > - * > - * And if we were unable to get a new slab from the partial slab lists then > - * we need to allocate a new slab. This is the slowest path since it involves > - * a call to the page allocator and the setup of a new slab. > - * > - * Version of __slab_alloc to use when we know that preemption is > - * already disabled (which is the case for bulk allocation). > - */ > -static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, > - unsigned long addr, struct kmem_cache_cpu *c, unsigned int orig_size) > -{ > - void *freelist; > - struct slab *slab; > - unsigned long flags; > - struct partial_context pc; > - > - stat(s, ALLOC_SLOWPATH); > - > -reread_slab: > - > - slab = READ_ONCE(c->slab); > - if (!slab) { > - /* > - * if the node is not online or has no normal memory, just > - * ignore the node constraint > - */ > - if (unlikely(node != NUMA_NO_NODE && > - !node_isset(node, slab_nodes))) > - node = NUMA_NO_NODE; > - goto new_slab; > - } > -redo: > - > - if (unlikely(!node_match(slab, node))) { > - /* > - * same as above but node_match() being false already > - * implies node != NUMA_NO_NODE > - */ > - if (!node_isset(node, slab_nodes)) { > - node = NUMA_NO_NODE; > - } else { > - stat(s, ALLOC_NODE_MISMATCH); > - goto deactivate_slab; > - } > - } > - > - /* > - * By rights, we should be searching for a slab page that was > - * PFMEMALLOC but right now, we are losing the pfmemalloc > - * information when the page leaves the per-cpu allocator > - */ > - if (unlikely(!pfmemalloc_match(slab, gfpflags))) > - goto deactivate_slab; > - > - /* must check again c->slab in case we got preempted and it changed */ > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (unlikely(slab != c->slab)) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - goto reread_slab; > - } > - freelist = c->freelist; > - if (freelist) > - goto load_freelist; > - > - freelist = get_freelist(s, slab); > - > - if (!freelist) { > - c->slab = NULL; > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - stat(s, DEACTIVATE_BYPASS); > - goto new_slab; > - } > - > - stat(s, ALLOC_REFILL); > - > -load_freelist: > - > - lockdep_assert_held(this_cpu_ptr(&s->cpu_slab->lock)); > - > - /* > - * freelist is pointing to the list of objects to be used. > - * slab is pointing to the slab from which the objects are obtained. > - * That slab must be frozen for per cpu allocations to work. > - */ > - VM_BUG_ON(!c->slab->frozen); > - c->freelist = get_freepointer(s, freelist); > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - return freelist; > - > -deactivate_slab: > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (slab != c->slab) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - goto reread_slab; > - } > - freelist = c->freelist; > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - deactivate_slab(s, slab, freelist); > - > -new_slab: > - > - if (slub_percpu_partial(c)) { > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (unlikely(c->slab)) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - goto reread_slab; > - } > - if (unlikely(!slub_percpu_partial(c))) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - /* we were preempted and partial list got empty */ > - goto new_objects; > - } > - > - slab = c->slab = slub_percpu_partial(c); > - slub_set_percpu_partial(c, slab); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - stat(s, CPU_PARTIAL_ALLOC); > - goto redo; > - } > - > -new_objects: > - > - pc.flags = gfpflags; > - pc.slab = &slab; > - pc.orig_size = orig_size; > - freelist = get_partial(s, node, &pc); > - if (freelist) > - goto check_new_slab; > - > - slub_put_cpu_ptr(s->cpu_slab); > - slab = new_slab(s, gfpflags, node); > - c = slub_get_cpu_ptr(s->cpu_slab); > - > - if (unlikely(!slab)) { > - slab_out_of_memory(s, gfpflags, node); > - return NULL; > - } > - > - stat(s, ALLOC_SLAB); > - > - if (kmem_cache_debug(s)) { > - freelist = alloc_single_from_new_slab(s, slab, orig_size); > - > - if (unlikely(!freelist)) > - goto new_objects; > - > - if (s->flags & SLAB_STORE_USER) > - set_track(s, freelist, TRACK_ALLOC, addr); > - > - return freelist; > - } > - > - /* > - * No other reference to the slab yet so we can > - * muck around with it freely without cmpxchg > - */ > - freelist = slab->freelist; > - slab->freelist = NULL; > - slab->inuse = slab->objects; > - slab->frozen = 1; > - > - inc_slabs_node(s, slab_nid(slab), slab->objects); > - > -check_new_slab: > - > - if (kmem_cache_debug(s)) { > - /* > - * For debug caches here we had to go through > - * alloc_single_from_partial() so just store the tracking info > - * and return the object > - */ > - if (s->flags & SLAB_STORE_USER) > - set_track(s, freelist, TRACK_ALLOC, addr); > - > - return freelist; > - } > - > - if (unlikely(!pfmemalloc_match(slab, gfpflags))) { > - /* > - * For !pfmemalloc_match() case we don't load freelist so that > - * we don't make further mismatched allocations easier. > - */ > - deactivate_slab(s, slab, get_freepointer(s, freelist)); > - return freelist; > - } > - > -retry_load_slab: > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (unlikely(c->slab)) { > - void *flush_freelist = c->freelist; > - struct slab *flush_slab = c->slab; > - > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - deactivate_slab(s, flush_slab, flush_freelist); > - > - stat(s, CPUSLAB_FLUSH); > - > - goto retry_load_slab; > - } > - c->slab = slab; > - > - goto load_freelist; > -} > - > -/* > - * A wrapper for ___slab_alloc() for contexts where preemption is not yet > - * disabled. Compensates for possible cpu changes by refetching the per cpu area > - * pointer. > - */ > -static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, > - unsigned long addr, struct kmem_cache_cpu *c, unsigned int orig_size) > -{ > - void *p; > - > -#ifdef CONFIG_PREEMPT_COUNT > - /* > - * We may have been preempted and rescheduled on a different > - * cpu before disabling preemption. Need to reload cpu area > - * pointer. > - */ > - c = slub_get_cpu_ptr(s->cpu_slab); > -#endif > - > - p = ___slab_alloc(s, gfpflags, node, addr, c, orig_size); > -#ifdef CONFIG_PREEMPT_COUNT > - slub_put_cpu_ptr(s->cpu_slab); > -#endif > - return p; > -} > - > -static __always_inline void *__slab_alloc_node(struct kmem_cache *s, > - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) > -{ > - struct kmem_cache_cpu *c; > - struct slab *slab; > - unsigned long tid; > - void *object; > - > -redo: > - /* > - * Must read kmem_cache cpu data via this cpu ptr. Preemption is > - * enabled. We may switch back and forth between cpus while > - * reading from one cpu area. That does not matter as long > - * as we end up on the original cpu again when doing the cmpxchg. > - * > - * We must guarantee that tid and kmem_cache_cpu are retrieved on the > - * same cpu. We read first the kmem_cache_cpu pointer and use it to read > - * the tid. If we are preempted and switched to another cpu between the > - * two reads, it's OK as the two are still associated with the same cpu > - * and cmpxchg later will validate the cpu. > - */ > - c = raw_cpu_ptr(s->cpu_slab); > - tid = READ_ONCE(c->tid); > - > - /* > - * Irqless object alloc/free algorithm used here depends on sequence > - * of fetching cpu_slab's data. tid should be fetched before anything > - * on c to guarantee that object and slab associated with previous tid > - * won't be used with current tid. If we fetch tid first, object and > - * slab could be one associated with next tid and our alloc/free > - * request will be failed. In this case, we will retry. So, no problem. > - */ > - barrier(); > - > - /* > - * The transaction ids are globally unique per cpu and per operation on > - * a per cpu queue. Thus they can be guarantee that the cmpxchg_double > - * occurs on the right processor and that there was no operation on the > - * linked list in between. > - */ > - > - object = c->freelist; > - slab = c->slab; > - > - if (!USE_LOCKLESS_FAST_PATH() || > - unlikely(!object || !slab || !node_match(slab, node))) { > - object = __slab_alloc(s, gfpflags, node, addr, c, orig_size); > - } else { > - void *next_object = get_freepointer_safe(s, object); > - > - /* > - * The cmpxchg will only match if there was no additional > - * operation and if we are on the right processor. > - * > - * The cmpxchg does the following atomically (without lock > - * semantics!) > - * 1. Relocate first pointer to the current per cpu area. > - * 2. Verify that tid and freelist have not been changed > - * 3. If they were not changed replace tid and freelist > - * > - * Since this is without lock semantics the protection is only > - * against code executing on this cpu *not* from access by > - * other cpus. > - */ > - if (unlikely(!this_cpu_cmpxchg_double( > - s->cpu_slab->freelist, s->cpu_slab->tid, > - object, tid, > - next_object, next_tid(tid)))) { > - > - note_cmpxchg_failure("slab_alloc", s, tid); > - goto redo; > - } > - prefetch_freepointer(s, next_object); > - stat(s, ALLOC_FASTPATH); > - } > - > - return object; > -} > -#else /* CONFIG_SLUB_TINY */ > -static void *__slab_alloc_node(struct kmem_cache *s, > - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) > -{ > - struct partial_context pc; > - struct slab *slab; > - void *object; > - > - pc.flags = gfpflags; > - pc.slab = &slab; > - pc.orig_size = orig_size; > - object = get_partial(s, node, &pc); > - > - if (object) > - return object; > - > - slab = new_slab(s, gfpflags, node); > - if (unlikely(!slab)) { > - slab_out_of_memory(s, gfpflags, node); > - return NULL; > - } > - > - object = alloc_single_from_new_slab(s, slab, orig_size); > - > - return object; > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -/* > - * If the object has been wiped upon free, make sure it's fully initialized by > - * zeroing out freelist pointer. > - */ > -static __always_inline void maybe_wipe_obj_freeptr(struct kmem_cache *s, > - void *obj) > -{ > - if (unlikely(slab_want_init_on_free(s)) && obj) > - memset((void *)((char *)kasan_reset_tag(obj) + s->offset), > - 0, sizeof(void *)); > -} > - > -/* > - * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc) > - * have the fastpath folded into their functions. So no function call > - * overhead for requests that can be satisfied on the fastpath. > - * > - * The fastpath works by first checking if the lockless freelist can be used. > - * If not then __slab_alloc is called for slow processing. > - * > - * Otherwise we can simply pick the next object from the lockless free list. > - */ > -static __fastpath_inline void *slab_alloc_node(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) > -{ > - void *object; > - struct obj_cgroup *objcg = NULL; > - bool init = false; > - > - s = slab_pre_alloc_hook(s, lru, &objcg, 1, gfpflags); > - if (!s) > - return NULL; > - > - object = kfence_alloc(s, orig_size, gfpflags); > - if (unlikely(object)) > - goto out; > - > - object = __slab_alloc_node(s, gfpflags, node, addr, orig_size); > - > - maybe_wipe_obj_freeptr(s, object); > - init = slab_want_init_on_alloc(gfpflags, s); > - > -out: > - /* > - * When init equals 'true', like for kzalloc() family, only > - * @orig_size bytes might be zeroed instead of s->object_size > - */ > - slab_post_alloc_hook(s, objcg, gfpflags, 1, &object, init, orig_size); > - > - return object; > -} > - > -static __fastpath_inline void *slab_alloc(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags, unsigned long addr, size_t orig_size) > -{ > - return slab_alloc_node(s, lru, gfpflags, NUMA_NO_NODE, addr, orig_size); > -} > - > -static __fastpath_inline > -void *__kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags) > -{ > - void *ret = slab_alloc(s, lru, gfpflags, _RET_IP_, s->object_size); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, s, gfpflags, NUMA_NO_NODE); > - > - return ret; > -} > - > -void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) > -{ > - return __kmem_cache_alloc_lru(s, NULL, gfpflags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc); > - > -void *kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags) > -{ > - return __kmem_cache_alloc_lru(s, lru, gfpflags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_lru); > - > -void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, > - int node, size_t orig_size, > - unsigned long caller) > -{ > - return slab_alloc_node(s, NULL, gfpflags, node, > - caller, orig_size); > -} > - > -void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node) > -{ > - void *ret = slab_alloc_node(s, NULL, gfpflags, node, _RET_IP_, s->object_size); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, s, gfpflags, node); > - > - return ret; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_node); > - > -static noinline void free_to_partial_list( > - struct kmem_cache *s, struct slab *slab, > - void *head, void *tail, int bulk_cnt, > - unsigned long addr) > -{ > - struct kmem_cache_node *n = get_node(s, slab_nid(slab)); > - struct slab *slab_free = NULL; > - int cnt = bulk_cnt; > - unsigned long flags; > - depot_stack_handle_t handle = 0; > - > - if (s->flags & SLAB_STORE_USER) > - handle = set_track_prepare(); > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - if (free_debug_processing(s, slab, head, tail, &cnt, addr, handle)) { > - void *prior = slab->freelist; > - > - /* Perform the actual freeing while we still hold the locks */ > - slab->inuse -= cnt; > - set_freepointer(s, tail, prior); > - slab->freelist = head; > - > - /* > - * If the slab is empty, and node's partial list is full, > - * it should be discarded anyway no matter it's on full or > - * partial list. > - */ > - if (slab->inuse == 0 && n->nr_partial >= s->min_partial) > - slab_free = slab; > - > - if (!prior) { > - /* was on full list */ > - remove_full(s, n, slab); > - if (!slab_free) { > - add_partial(n, slab, DEACTIVATE_TO_TAIL); > - stat(s, FREE_ADD_PARTIAL); > - } > - } else if (slab_free) { > - remove_partial(n, slab); > - stat(s, FREE_REMOVE_PARTIAL); > - } > - } > - > - if (slab_free) { > - /* > - * Update the counters while still holding n->list_lock to > - * prevent spurious validation warnings > - */ > - dec_slabs_node(s, slab_nid(slab_free), slab_free->objects); > - } > - > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - if (slab_free) { > - stat(s, FREE_SLAB); > - free_slab(s, slab_free); > - } > -} > - > -/* > - * Slow path handling. This may still be called frequently since objects > - * have a longer lifetime than the cpu slabs in most processing loads. > - * > - * So we still attempt to reduce cache line usage. Just take the slab > - * lock and free the item. If there is no additional partial slab > - * handling required then we can return immediately. > - */ > -static void __slab_free(struct kmem_cache *s, struct slab *slab, > - void *head, void *tail, int cnt, > - unsigned long addr) > - > -{ > - void *prior; > - int was_frozen; > - struct slab new; > - unsigned long counters; > - struct kmem_cache_node *n = NULL; > - unsigned long flags; > - > - stat(s, FREE_SLOWPATH); > - > - if (kfence_free(head)) > - return; > - > - if (IS_ENABLED(CONFIG_SLUB_TINY) || kmem_cache_debug(s)) { > - free_to_partial_list(s, slab, head, tail, cnt, addr); > - return; > - } > - > - do { > - if (unlikely(n)) { > - spin_unlock_irqrestore(&n->list_lock, flags); > - n = NULL; > - } > - prior = slab->freelist; > - counters = slab->counters; > - set_freepointer(s, tail, prior); > - new.counters = counters; > - was_frozen = new.frozen; > - new.inuse -= cnt; > - if ((!new.inuse || !prior) && !was_frozen) { > - > - if (kmem_cache_has_cpu_partial(s) && !prior) { > - > - /* > - * Slab was on no list before and will be > - * partially empty > - * We can defer the list move and instead > - * freeze it. > - */ > - new.frozen = 1; > - > - } else { /* Needs to be taken off a list */ > - > - n = get_node(s, slab_nid(slab)); > - /* > - * Speculatively acquire the list_lock. > - * If the cmpxchg does not succeed then we may > - * drop the list_lock without any processing. > - * > - * Otherwise the list_lock will synchronize with > - * other processors updating the list of slabs. > - */ > - spin_lock_irqsave(&n->list_lock, flags); > - > - } > - } > - > - } while (!cmpxchg_double_slab(s, slab, > - prior, counters, > - head, new.counters, > - "__slab_free")); > - > - if (likely(!n)) { > - > - if (likely(was_frozen)) { > - /* > - * The list lock was not taken therefore no list > - * activity can be necessary. > - */ > - stat(s, FREE_FROZEN); > - } else if (new.frozen) { > - /* > - * If we just froze the slab then put it onto the > - * per cpu partial list. > - */ > - put_cpu_partial(s, slab, 1); > - stat(s, CPU_PARTIAL_FREE); > - } > - > - return; > - } > - > - if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) > - goto slab_empty; > - > - /* > - * Objects left in the slab. If it was not on the partial list before > - * then add it. > - */ > - if (!kmem_cache_has_cpu_partial(s) && unlikely(!prior)) { > - remove_full(s, n, slab); > - add_partial(n, slab, DEACTIVATE_TO_TAIL); > - stat(s, FREE_ADD_PARTIAL); > - } > - spin_unlock_irqrestore(&n->list_lock, flags); > - return; > - > -slab_empty: > - if (prior) { > - /* > - * Slab on the partial list. > - */ > - remove_partial(n, slab); > - stat(s, FREE_REMOVE_PARTIAL); > - } else { > - /* Slab must be on the full list */ > - remove_full(s, n, slab); > - } > - > - spin_unlock_irqrestore(&n->list_lock, flags); > - stat(s, FREE_SLAB); > - discard_slab(s, slab); > -} > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Fastpath with forced inlining to produce a kfree and kmem_cache_free that > - * can perform fastpath freeing without additional function calls. > - * > - * The fastpath is only possible if we are freeing to the current cpu slab > - * of this processor. This typically the case if we have just allocated > - * the item before. > - * > - * If fastpath is not possible then fall back to __slab_free where we deal > - * with all sorts of special processing. > - * > - * Bulk free of a freelist with several objects (all pointing to the > - * same slab) possible by specifying head and tail ptr, plus objects > - * count (cnt). Bulk free indicated by tail pointer being set. > - */ > -static __always_inline void do_slab_free(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, > - int cnt, unsigned long addr) > -{ > - void *tail_obj = tail ? : head; > - struct kmem_cache_cpu *c; > - unsigned long tid; > - void **freelist; > - > -redo: > - /* > - * Determine the currently cpus per cpu slab. > - * The cpu may change afterward. However that does not matter since > - * data is retrieved via this pointer. If we are on the same cpu > - * during the cmpxchg then the free will succeed. > - */ > - c = raw_cpu_ptr(s->cpu_slab); > - tid = READ_ONCE(c->tid); > - > - /* Same with comment on barrier() in slab_alloc_node() */ > - barrier(); > - > - if (unlikely(slab != c->slab)) { > - __slab_free(s, slab, head, tail_obj, cnt, addr); > - return; > - } > - > - if (USE_LOCKLESS_FAST_PATH()) { > - freelist = READ_ONCE(c->freelist); > - > - set_freepointer(s, tail_obj, freelist); > - > - if (unlikely(!this_cpu_cmpxchg_double( > - s->cpu_slab->freelist, s->cpu_slab->tid, > - freelist, tid, > - head, next_tid(tid)))) { > - > - note_cmpxchg_failure("slab_free", s, tid); > - goto redo; > - } > - } else { > - /* Update the free list under the local lock */ > - local_lock(&s->cpu_slab->lock); > - c = this_cpu_ptr(s->cpu_slab); > - if (unlikely(slab != c->slab)) { > - local_unlock(&s->cpu_slab->lock); > - goto redo; > - } > - tid = c->tid; > - freelist = c->freelist; > - > - set_freepointer(s, tail_obj, freelist); > - c->freelist = head; > - c->tid = next_tid(tid); > - > - local_unlock(&s->cpu_slab->lock); > - } > - stat(s, FREE_FASTPATH); > -} > -#else /* CONFIG_SLUB_TINY */ > -static void do_slab_free(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, > - int cnt, unsigned long addr) > -{ > - void *tail_obj = tail ? : head; > - > - __slab_free(s, slab, head, tail_obj, cnt, addr); > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -static __fastpath_inline void slab_free(struct kmem_cache *s, struct slab *slab, > - void *head, void *tail, void **p, int cnt, > - unsigned long addr) > -{ > - memcg_slab_free_hook(s, slab, p, cnt); > - /* > - * With KASAN enabled slab_free_freelist_hook modifies the freelist > - * to remove objects, whose reuse must be delayed. > - */ > - if (slab_free_freelist_hook(s, &head, &tail, &cnt)) > - do_slab_free(s, slab, head, tail, cnt, addr); > -} > - > -#ifdef CONFIG_KASAN_GENERIC > -void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr) > -{ > - do_slab_free(cache, virt_to_slab(x), x, NULL, 1, addr); > -} > -#endif > - > -void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller) > -{ > - slab_free(s, virt_to_slab(x), x, NULL, &x, 1, caller); > -} > - > -void kmem_cache_free(struct kmem_cache *s, void *x) > -{ > - s = cache_from_obj(s, x); > - if (!s) > - return; > - trace_kmem_cache_free(_RET_IP_, x, s); > - slab_free(s, virt_to_slab(x), x, NULL, &x, 1, _RET_IP_); > -} > -EXPORT_SYMBOL(kmem_cache_free); > - > -struct detached_freelist { > - struct slab *slab; > - void *tail; > - void *freelist; > - int cnt; > - struct kmem_cache *s; > -}; > - > -/* > - * This function progressively scans the array with free objects (with > - * a limited look ahead) and extract objects belonging to the same > - * slab. It builds a detached freelist directly within the given > - * slab/objects. This can happen without any need for > - * synchronization, because the objects are owned by running process. > - * The freelist is build up as a single linked list in the objects. > - * The idea is, that this detached freelist can then be bulk > - * transferred to the real freelist(s), but only requiring a single > - * synchronization primitive. Look ahead in the array is limited due > - * to performance reasons. > - */ > -static inline > -int build_detached_freelist(struct kmem_cache *s, size_t size, > - void **p, struct detached_freelist *df) > -{ > - int lookahead = 3; > - void *object; > - struct folio *folio; > - size_t same; > - > - object = p[--size]; > - folio = virt_to_folio(object); > - if (!s) { > - /* Handle kalloc'ed objects */ > - if (unlikely(!folio_test_slab(folio))) { > - free_large_kmalloc(folio, object); > - df->slab = NULL; > - return size; > - } > - /* Derive kmem_cache from object */ > - df->slab = folio_slab(folio); > - df->s = df->slab->slab_cache; > - } else { > - df->slab = folio_slab(folio); > - df->s = cache_from_obj(s, object); /* Support for memcg */ > - } > - > - /* Start new detached freelist */ > - df->tail = object; > - df->freelist = object; > - df->cnt = 1; > - > - if (is_kfence_address(object)) > - return size; > - > - set_freepointer(df->s, object, NULL); > - > - same = size; > - while (size) { > - object = p[--size]; > - /* df->slab is always set at this point */ > - if (df->slab == virt_to_slab(object)) { > - /* Opportunity build freelist */ > - set_freepointer(df->s, object, df->freelist); > - df->freelist = object; > - df->cnt++; > - same--; > - if (size != same) > - swap(p[size], p[same]); > - continue; > - } > - > - /* Limit look ahead search */ > - if (!--lookahead) > - break; > - } > - > - return same; > -} > - > -/* Note that interrupts must be enabled when calling this function. */ > -void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p) > -{ > - if (!size) > - return; > - > - do { > - struct detached_freelist df; > - > - size = build_detached_freelist(s, size, p, &df); > - if (!df.slab) > - continue; > - > - slab_free(df.s, df.slab, df.freelist, df.tail, &p[size], df.cnt, > - _RET_IP_); > - } while (likely(size)); > -} > -EXPORT_SYMBOL(kmem_cache_free_bulk); > - > -#ifndef CONFIG_SLUB_TINY > -static inline int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, > - size_t size, void **p, struct obj_cgroup *objcg) > -{ > - struct kmem_cache_cpu *c; > - unsigned long irqflags; > - int i; > - > - /* > - * Drain objects in the per cpu slab, while disabling local > - * IRQs, which protects against PREEMPT and interrupts > - * handlers invoking normal fastpath. > - */ > - c = slub_get_cpu_ptr(s->cpu_slab); > - local_lock_irqsave(&s->cpu_slab->lock, irqflags); > - > - for (i = 0; i < size; i++) { > - void *object = kfence_alloc(s, s->object_size, flags); > - > - if (unlikely(object)) { > - p[i] = object; > - continue; > - } > - > - object = c->freelist; > - if (unlikely(!object)) { > - /* > - * We may have removed an object from c->freelist using > - * the fastpath in the previous iteration; in that case, > - * c->tid has not been bumped yet. > - * Since ___slab_alloc() may reenable interrupts while > - * allocating memory, we should bump c->tid now. > - */ > - c->tid = next_tid(c->tid); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, irqflags); > - > - /* > - * Invoking slow path likely have side-effect > - * of re-populating per CPU c->freelist > - */ > - p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE, > - _RET_IP_, c, s->object_size); > - if (unlikely(!p[i])) > - goto error; > - > - c = this_cpu_ptr(s->cpu_slab); > - maybe_wipe_obj_freeptr(s, p[i]); > - > - local_lock_irqsave(&s->cpu_slab->lock, irqflags); > - > - continue; /* goto for-loop */ > - } > - c->freelist = get_freepointer(s, object); > - p[i] = object; > - maybe_wipe_obj_freeptr(s, p[i]); > - } > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, irqflags); > - slub_put_cpu_ptr(s->cpu_slab); > - > - return i; > - > -error: > - slub_put_cpu_ptr(s->cpu_slab); > - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); > - kmem_cache_free_bulk(s, i, p); > - return 0; > - > -} > -#else /* CONFIG_SLUB_TINY */ > -static int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, > - size_t size, void **p, struct obj_cgroup *objcg) > -{ > - int i; > - > - for (i = 0; i < size; i++) { > - void *object = kfence_alloc(s, s->object_size, flags); > - > - if (unlikely(object)) { > - p[i] = object; > - continue; > - } > - > - p[i] = __slab_alloc_node(s, flags, NUMA_NO_NODE, > - _RET_IP_, s->object_size); > - if (unlikely(!p[i])) > - goto error; > - > - maybe_wipe_obj_freeptr(s, p[i]); > - } > - > - return i; > - > -error: > - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); > - kmem_cache_free_bulk(s, i, p); > - return 0; > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -/* Note that interrupts must be enabled when calling this function. */ > -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, > - void **p) > -{ > - int i; > - struct obj_cgroup *objcg = NULL; > - > - if (!size) > - return 0; > - > - /* memcg and kmem_cache debug support */ > - s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); > - if (unlikely(!s)) > - return 0; > - > - i = __kmem_cache_alloc_bulk(s, flags, size, p, objcg); > - > - /* > - * memcg and kmem_cache debug support and memory initialization. > - * Done outside of the IRQ disabled fastpath loop. > - */ > - if (i != 0) > - slab_post_alloc_hook(s, objcg, flags, size, p, > - slab_want_init_on_alloc(flags, s), s->object_size); > - return i; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_bulk); > - > - > -/* > - * Object placement in a slab is made very easy because we always start at > - * offset 0. If we tune the size of the object to the alignment then we can > - * get the required alignment by putting one properly sized object after > - * another. > - * > - * Notice that the allocation order determines the sizes of the per cpu > - * caches. Each processor has always one slab available for allocations. > - * Increasing the allocation order reduces the number of times that slabs > - * must be moved on and off the partial lists and is therefore a factor in > - * locking overhead. > - */ > - > -/* > - * Minimum / Maximum order of slab pages. This influences locking overhead > - * and slab fragmentation. A higher order reduces the number of partial slabs > - * and increases the number of allocations possible without having to > - * take the list_lock. > - */ > -static unsigned int slub_min_order; > -static unsigned int slub_max_order = > - IS_ENABLED(CONFIG_SLUB_TINY) ? 1 : PAGE_ALLOC_COSTLY_ORDER; > -static unsigned int slub_min_objects; > - > -/* > - * Calculate the order of allocation given an slab object size. > - * > - * The order of allocation has significant impact on performance and other > - * system components. Generally order 0 allocations should be preferred since > - * order 0 does not cause fragmentation in the page allocator. Larger objects > - * be problematic to put into order 0 slabs because there may be too much > - * unused space left. We go to a higher order if more than 1/16th of the slab > - * would be wasted. > - * > - * In order to reach satisfactory performance we must ensure that a minimum > - * number of objects is in one slab. Otherwise we may generate too much > - * activity on the partial lists which requires taking the list_lock. This is > - * less a concern for large slabs though which are rarely used. > - * > - * slub_max_order specifies the order where we begin to stop considering the > - * number of objects in a slab as critical. If we reach slub_max_order then > - * we try to keep the page order as low as possible. So we accept more waste > - * of space in favor of a small page order. > - * > - * Higher order allocations also allow the placement of more objects in a > - * slab and thereby reduce object handling overhead. If the user has > - * requested a higher minimum order then we start with that one instead of > - * the smallest order which will fit the object. > - */ > -static inline unsigned int calc_slab_order(unsigned int size, > - unsigned int min_objects, unsigned int max_order, > - unsigned int fract_leftover) > -{ > - unsigned int min_order = slub_min_order; > - unsigned int order; > - > - if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE) > - return get_order(size * MAX_OBJS_PER_PAGE) - 1; > - > - for (order = max(min_order, (unsigned int)get_order(min_objects * size)); > - order <= max_order; order++) { > - > - unsigned int slab_size = (unsigned int)PAGE_SIZE << order; > - unsigned int rem; > - > - rem = slab_size % size; > - > - if (rem <= slab_size / fract_leftover) > - break; > - } > - > - return order; > -} > - > -static inline int calculate_order(unsigned int size) > -{ > - unsigned int order; > - unsigned int min_objects; > - unsigned int max_objects; > - unsigned int nr_cpus; > - > - /* > - * Attempt to find best configuration for a slab. This > - * works by first attempting to generate a layout with > - * the best configuration and backing off gradually. > - * > - * First we increase the acceptable waste in a slab. Then > - * we reduce the minimum objects required in a slab. > - */ > - min_objects = slub_min_objects; > - if (!min_objects) { > - /* > - * Some architectures will only update present cpus when > - * onlining them, so don't trust the number if it's just 1. But > - * we also don't want to use nr_cpu_ids always, as on some other > - * architectures, there can be many possible cpus, but never > - * onlined. Here we compromise between trying to avoid too high > - * order on systems that appear larger than they are, and too > - * low order on systems that appear smaller than they are. > - */ > - nr_cpus = num_present_cpus(); > - if (nr_cpus <= 1) > - nr_cpus = nr_cpu_ids; > - min_objects = 4 * (fls(nr_cpus) + 1); > - } > - max_objects = order_objects(slub_max_order, size); > - min_objects = min(min_objects, max_objects); > - > - while (min_objects > 1) { > - unsigned int fraction; > - > - fraction = 16; > - while (fraction >= 4) { > - order = calc_slab_order(size, min_objects, > - slub_max_order, fraction); > - if (order <= slub_max_order) > - return order; > - fraction /= 2; > - } > - min_objects--; > - } > - > - /* > - * We were unable to place multiple objects in a slab. Now > - * lets see if we can place a single object there. > - */ > - order = calc_slab_order(size, 1, slub_max_order, 1); > - if (order <= slub_max_order) > - return order; > - > - /* > - * Doh this slab cannot be placed using slub_max_order. > - */ > - order = calc_slab_order(size, 1, MAX_ORDER, 1); > - if (order < MAX_ORDER) > - return order; > - return -ENOSYS; > -} > - > -static void > -init_kmem_cache_node(struct kmem_cache_node *n) > -{ > - n->nr_partial = 0; > - spin_lock_init(&n->list_lock); > - INIT_LIST_HEAD(&n->partial); > -#ifdef CONFIG_SLUB_DEBUG > - atomic_long_set(&n->nr_slabs, 0); > - atomic_long_set(&n->total_objects, 0); > - INIT_LIST_HEAD(&n->full); > -#endif > -} > - > -#ifndef CONFIG_SLUB_TINY > -static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) > -{ > - BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE < > - NR_KMALLOC_TYPES * KMALLOC_SHIFT_HIGH * > - sizeof(struct kmem_cache_cpu)); > - > - /* > - * Must align to double word boundary for the double cmpxchg > - * instructions to work; see __pcpu_double_call_return_bool(). > - */ > - s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu), > - 2 * sizeof(void *)); > - > - if (!s->cpu_slab) > - return 0; > - > - init_kmem_cache_cpus(s); > - > - return 1; > -} > -#else > -static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) > -{ > - return 1; > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -static struct kmem_cache *kmem_cache_node; > - > -/* > - * No kmalloc_node yet so do it by hand. We know that this is the first > - * slab on the node for this slabcache. There are no concurrent accesses > - * possible. > - * > - * Note that this function only works on the kmem_cache_node > - * when allocating for the kmem_cache_node. This is used for bootstrapping > - * memory on a fresh node that has no slab structures yet. > - */ > -static void early_kmem_cache_node_alloc(int node) > -{ > - struct slab *slab; > - struct kmem_cache_node *n; > - > - BUG_ON(kmem_cache_node->size < sizeof(struct kmem_cache_node)); > - > - slab = new_slab(kmem_cache_node, GFP_NOWAIT, node); > - > - BUG_ON(!slab); > - inc_slabs_node(kmem_cache_node, slab_nid(slab), slab->objects); > - if (slab_nid(slab) != node) { > - pr_err("SLUB: Unable to allocate memory from node %d\n", node); > - pr_err("SLUB: Allocating a useless per node structure in order to be able to continue\n"); > - } > - > - n = slab->freelist; > - BUG_ON(!n); > -#ifdef CONFIG_SLUB_DEBUG > - init_object(kmem_cache_node, n, SLUB_RED_ACTIVE); > - init_tracking(kmem_cache_node, n); > -#endif > - n = kasan_slab_alloc(kmem_cache_node, n, GFP_KERNEL, false); > - slab->freelist = get_freepointer(kmem_cache_node, n); > - slab->inuse = 1; > - kmem_cache_node->node[node] = n; > - init_kmem_cache_node(n); > - inc_slabs_node(kmem_cache_node, node, slab->objects); > - > - /* > - * No locks need to be taken here as it has just been > - * initialized and there is no concurrent access. > - */ > - __add_partial(n, slab, DEACTIVATE_TO_HEAD); > -} > - > -static void free_kmem_cache_nodes(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - s->node[node] = NULL; > - kmem_cache_free(kmem_cache_node, n); > - } > -} > - > -void __kmem_cache_release(struct kmem_cache *s) > -{ > - cache_random_seq_destroy(s); > -#ifndef CONFIG_SLUB_TINY > - free_percpu(s->cpu_slab); > -#endif > - free_kmem_cache_nodes(s); > -} > - > -static int init_kmem_cache_nodes(struct kmem_cache *s) > -{ > - int node; > - > - for_each_node_mask(node, slab_nodes) { > - struct kmem_cache_node *n; > - > - if (slab_state == DOWN) { > - early_kmem_cache_node_alloc(node); > - continue; > - } > - n = kmem_cache_alloc_node(kmem_cache_node, > - GFP_KERNEL, node); > - > - if (!n) { > - free_kmem_cache_nodes(s); > - return 0; > - } > - > - init_kmem_cache_node(n); > - s->node[node] = n; > - } > - return 1; > -} > - > -static void set_cpu_partial(struct kmem_cache *s) > -{ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - unsigned int nr_objects; > - > - /* > - * cpu_partial determined the maximum number of objects kept in the > - * per cpu partial lists of a processor. > - * > - * Per cpu partial lists mainly contain slabs that just have one > - * object freed. If they are used for allocation then they can be > - * filled up again with minimal effort. The slab will never hit the > - * per node partial lists and therefore no locking will be required. > - * > - * For backwards compatibility reasons, this is determined as number > - * of objects, even though we now limit maximum number of pages, see > - * slub_set_cpu_partial() > - */ > - if (!kmem_cache_has_cpu_partial(s)) > - nr_objects = 0; > - else if (s->size >= PAGE_SIZE) > - nr_objects = 6; > - else if (s->size >= 1024) > - nr_objects = 24; > - else if (s->size >= 256) > - nr_objects = 52; > - else > - nr_objects = 120; > - > - slub_set_cpu_partial(s, nr_objects); > -#endif > -} > - > -/* > - * calculate_sizes() determines the order and the distribution of data within > - * a slab object. > - */ > -static int calculate_sizes(struct kmem_cache *s) > -{ > - slab_flags_t flags = s->flags; > - unsigned int size = s->object_size; > - unsigned int order; > - > - /* > - * Round up object size to the next word boundary. We can only > - * place the free pointer at word boundaries and this determines > - * the possible location of the free pointer. > - */ > - size = ALIGN(size, sizeof(void *)); > - > -#ifdef CONFIG_SLUB_DEBUG > - /* > - * Determine if we can poison the object itself. If the user of > - * the slab may touch the object after free or before allocation > - * then we should never poison the object itself. > - */ > - if ((flags & SLAB_POISON) && !(flags & SLAB_TYPESAFE_BY_RCU) && > - !s->ctor) > - s->flags |= __OBJECT_POISON; > - else > - s->flags &= ~__OBJECT_POISON; > - > - > - /* > - * If we are Redzoning then check if there is some space between the > - * end of the object and the free pointer. If not then add an > - * additional word to have some bytes to store Redzone information. > - */ > - if ((flags & SLAB_RED_ZONE) && size == s->object_size) > - size += sizeof(void *); > -#endif > - > - /* > - * With that we have determined the number of bytes in actual use > - * by the object and redzoning. > - */ > - s->inuse = size; > - > - if (slub_debug_orig_size(s) || > - (flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) || > - ((flags & SLAB_RED_ZONE) && s->object_size < sizeof(void *)) || > - s->ctor) { > - /* > - * Relocate free pointer after the object if it is not > - * permitted to overwrite the first word of the object on > - * kmem_cache_free. > - * > - * This is the case if we do RCU, have a constructor or > - * destructor, are poisoning the objects, or are > - * redzoning an object smaller than sizeof(void *). > - * > - * The assumption that s->offset >= s->inuse means free > - * pointer is outside of the object is used in the > - * freeptr_outside_object() function. If that is no > - * longer true, the function needs to be modified. > - */ > - s->offset = size; > - size += sizeof(void *); > - } else { > - /* > - * Store freelist pointer near middle of object to keep > - * it away from the edges of the object to avoid small > - * sized over/underflows from neighboring allocations. > - */ > - s->offset = ALIGN_DOWN(s->object_size / 2, sizeof(void *)); > - } > - > -#ifdef CONFIG_SLUB_DEBUG > - if (flags & SLAB_STORE_USER) { > - /* > - * Need to store information about allocs and frees after > - * the object. > - */ > - size += 2 * sizeof(struct track); > - > - /* Save the original kmalloc request size */ > - if (flags & SLAB_KMALLOC) > - size += sizeof(unsigned int); > - } > -#endif > - > - kasan_cache_create(s, &size, &s->flags); > -#ifdef CONFIG_SLUB_DEBUG > - if (flags & SLAB_RED_ZONE) { > - /* > - * Add some empty padding so that we can catch > - * overwrites from earlier objects rather than let > - * tracking information or the free pointer be > - * corrupted if a user writes before the start > - * of the object. > - */ > - size += sizeof(void *); > - > - s->red_left_pad = sizeof(void *); > - s->red_left_pad = ALIGN(s->red_left_pad, s->align); > - size += s->red_left_pad; > - } > -#endif > - > - /* > - * SLUB stores one object immediately after another beginning from > - * offset 0. In order to align the objects we have to simply size > - * each object to conform to the alignment. > - */ > - size = ALIGN(size, s->align); > - s->size = size; > - s->reciprocal_size = reciprocal_value(size); > - order = calculate_order(size); > - > - if ((int)order < 0) > - return 0; > - > - s->allocflags = 0; > - if (order) > - s->allocflags |= __GFP_COMP; > - > - if (s->flags & SLAB_CACHE_DMA) > - s->allocflags |= GFP_DMA; > - > - if (s->flags & SLAB_CACHE_DMA32) > - s->allocflags |= GFP_DMA32; > - > - if (s->flags & SLAB_RECLAIM_ACCOUNT) > - s->allocflags |= __GFP_RECLAIMABLE; > - > - /* > - * Determine the number of objects per slab > - */ > - s->oo = oo_make(order, size); > - s->min = oo_make(get_order(size), size); > - > - return !!oo_objects(s->oo); > -} > - > -static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags) > -{ > - s->flags = kmem_cache_flags(s->size, flags, s->name); > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - s->random = get_random_long(); > -#endif > - > - if (!calculate_sizes(s)) > - goto error; > - if (disable_higher_order_debug) { > - /* > - * Disable debugging flags that store metadata if the min slab > - * order increased. > - */ > - if (get_order(s->size) > get_order(s->object_size)) { > - s->flags &= ~DEBUG_METADATA_FLAGS; > - s->offset = 0; > - if (!calculate_sizes(s)) > - goto error; > - } > - } > - > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ > - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) > - if (system_has_cmpxchg_double() && (s->flags & SLAB_NO_CMPXCHG) == 0) > - /* Enable fast mode */ > - s->flags |= __CMPXCHG_DOUBLE; > -#endif > - > - /* > - * The larger the object size is, the more slabs we want on the partial > - * list to avoid pounding the page allocator excessively. > - */ > - s->min_partial = min_t(unsigned long, MAX_PARTIAL, ilog2(s->size) / 2); > - s->min_partial = max_t(unsigned long, MIN_PARTIAL, s->min_partial); > - > - set_cpu_partial(s); > - > -#ifdef CONFIG_NUMA > - s->remote_node_defrag_ratio = 1000; > -#endif > - > - /* Initialize the pre-computed randomized freelist if slab is up */ > - if (slab_state >= UP) { > - if (init_cache_random_seq(s)) > - goto error; > - } > - > - if (!init_kmem_cache_nodes(s)) > - goto error; > - > - if (alloc_kmem_cache_cpus(s)) > - return 0; > - > -error: > - __kmem_cache_release(s); > - return -EINVAL; > -} > - > -static void list_slab_objects(struct kmem_cache *s, struct slab *slab, > - const char *text) > -{ > -#ifdef CONFIG_SLUB_DEBUG > - void *addr = slab_address(slab); > - void *p; > - > - slab_err(s, slab, text, s->name); > - > - spin_lock(&object_map_lock); > - __fill_map(object_map, s, slab); > - > - for_each_object(p, s, addr, slab->objects) { > - > - if (!test_bit(__obj_to_index(s, addr, p), object_map)) { > - pr_err("Object 0x%p @offset=%tu\n", p, p - addr); > - print_tracking(s, p); > - } > - } > - spin_unlock(&object_map_lock); > -#endif > -} > - > -/* > - * Attempt to free all partial slabs on a node. > - * This is called from __kmem_cache_shutdown(). We must take list_lock > - * because sysfs file might still access partial list after the shutdowning. > - */ > -static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n) > -{ > - LIST_HEAD(discard); > - struct slab *slab, *h; > - > - BUG_ON(irqs_disabled()); > - spin_lock_irq(&n->list_lock); > - list_for_each_entry_safe(slab, h, &n->partial, slab_list) { > - if (!slab->inuse) { > - remove_partial(n, slab); > - list_add(&slab->slab_list, &discard); > - } else { > - list_slab_objects(s, slab, > - "Objects remaining in %s on __kmem_cache_shutdown()"); > - } > - } > - spin_unlock_irq(&n->list_lock); > - > - list_for_each_entry_safe(slab, h, &discard, slab_list) > - discard_slab(s, slab); > -} > - > -bool __kmem_cache_empty(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) > - if (n->nr_partial || slabs_node(s, node)) > - return false; > - return true; > -} > - > -/* > - * Release all resources used by a slab cache. > - */ > -int __kmem_cache_shutdown(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - flush_all_cpus_locked(s); > - /* Attempt to free all objects */ > - for_each_kmem_cache_node(s, node, n) { > - free_partial(s, n); > - if (n->nr_partial || slabs_node(s, node)) > - return 1; > - } > - return 0; > -} > - > -#ifdef CONFIG_PRINTK > -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) > -{ > - void *base; > - int __maybe_unused i; > - unsigned int objnr; > - void *objp; > - void *objp0; > - struct kmem_cache *s = slab->slab_cache; > - struct track __maybe_unused *trackp; > - > - kpp->kp_ptr = object; > - kpp->kp_slab = slab; > - kpp->kp_slab_cache = s; > - base = slab_address(slab); > - objp0 = kasan_reset_tag(object); > -#ifdef CONFIG_SLUB_DEBUG > - objp = restore_red_left(s, objp0); > -#else > - objp = objp0; > -#endif > - objnr = obj_to_index(s, slab, objp); > - kpp->kp_data_offset = (unsigned long)((char *)objp0 - (char *)objp); > - objp = base + s->size * objnr; > - kpp->kp_objp = objp; > - if (WARN_ON_ONCE(objp < base || objp >= base + slab->objects * s->size > - || (objp - base) % s->size) || > - !(s->flags & SLAB_STORE_USER)) > - return; > -#ifdef CONFIG_SLUB_DEBUG > - objp = fixup_red_left(s, objp); > - trackp = get_track(s, objp, TRACK_ALLOC); > - kpp->kp_ret = (void *)trackp->addr; > -#ifdef CONFIG_STACKDEPOT > - { > - depot_stack_handle_t handle; > - unsigned long *entries; > - unsigned int nr_entries; > - > - handle = READ_ONCE(trackp->handle); > - if (handle) { > - nr_entries = stack_depot_fetch(handle, &entries); > - for (i = 0; i < KS_ADDRS_COUNT && i < nr_entries; i++) > - kpp->kp_stack[i] = (void *)entries[i]; > - } > - > - trackp = get_track(s, objp, TRACK_FREE); > - handle = READ_ONCE(trackp->handle); > - if (handle) { > - nr_entries = stack_depot_fetch(handle, &entries); > - for (i = 0; i < KS_ADDRS_COUNT && i < nr_entries; i++) > - kpp->kp_free_stack[i] = (void *)entries[i]; > - } > - } > -#endif > -#endif > -} > -#endif > - > -/******************************************************************** > - * Kmalloc subsystem > - *******************************************************************/ > - > -static int __init setup_slub_min_order(char *str) > -{ > - get_option(&str, (int *)&slub_min_order); > - > - return 1; > -} > - > -__setup("slub_min_order=", setup_slub_min_order); > - > -static int __init setup_slub_max_order(char *str) > -{ > - get_option(&str, (int *)&slub_max_order); > - slub_max_order = min(slub_max_order, (unsigned int)MAX_ORDER - 1); > - > - return 1; > -} > - > -__setup("slub_max_order=", setup_slub_max_order); > - > -static int __init setup_slub_min_objects(char *str) > -{ > - get_option(&str, (int *)&slub_min_objects); > - > - return 1; > -} > - > -__setup("slub_min_objects=", setup_slub_min_objects); > - > -#ifdef CONFIG_HARDENED_USERCOPY > -/* > - * Rejects incorrectly sized objects and objects that are to be copied > - * to/from userspace but do not fall entirely within the containing slab > - * cache's usercopy region. > - * > - * Returns NULL if check passes, otherwise const char * to name of cache > - * to indicate an error. > - */ > -void __check_heap_object(const void *ptr, unsigned long n, > - const struct slab *slab, bool to_user) > -{ > - struct kmem_cache *s; > - unsigned int offset; > - bool is_kfence = is_kfence_address(ptr); > - > - ptr = kasan_reset_tag(ptr); > - > - /* Find object and usable object size. */ > - s = slab->slab_cache; > - > - /* Reject impossible pointers. */ > - if (ptr < slab_address(slab)) > - usercopy_abort("SLUB object not in SLUB page?!", NULL, > - to_user, 0, n); > - > - /* Find offset within object. */ > - if (is_kfence) > - offset = ptr - kfence_object_start(ptr); > - else > - offset = (ptr - slab_address(slab)) % s->size; > - > - /* Adjust for redzone and reject if within the redzone. */ > - if (!is_kfence && kmem_cache_debug_flags(s, SLAB_RED_ZONE)) { > - if (offset < s->red_left_pad) > - usercopy_abort("SLUB object in left red zone", > - s->name, to_user, offset, n); > - offset -= s->red_left_pad; > - } > - > - /* Allow address range falling entirely within usercopy region. */ > - if (offset >= s->useroffset && > - offset - s->useroffset <= s->usersize && > - n <= s->useroffset - offset + s->usersize) > - return; > - > - usercopy_abort("SLUB object", s->name, to_user, offset, n); > -} > -#endif /* CONFIG_HARDENED_USERCOPY */ > - > -#define SHRINK_PROMOTE_MAX 32 > - > -/* > - * kmem_cache_shrink discards empty slabs and promotes the slabs filled > - * up most to the head of the partial lists. New allocations will then > - * fill those up and thus they can be removed from the partial lists. > - * > - * The slabs with the least items are placed last. This results in them > - * being allocated from last increasing the chance that the last objects > - * are freed in them. > - */ > -static int __kmem_cache_do_shrink(struct kmem_cache *s) > -{ > - int node; > - int i; > - struct kmem_cache_node *n; > - struct slab *slab; > - struct slab *t; > - struct list_head discard; > - struct list_head promote[SHRINK_PROMOTE_MAX]; > - unsigned long flags; > - int ret = 0; > - > - for_each_kmem_cache_node(s, node, n) { > - INIT_LIST_HEAD(&discard); > - for (i = 0; i < SHRINK_PROMOTE_MAX; i++) > - INIT_LIST_HEAD(promote + i); > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - /* > - * Build lists of slabs to discard or promote. > - * > - * Note that concurrent frees may occur while we hold the > - * list_lock. slab->inuse here is the upper limit. > - */ > - list_for_each_entry_safe(slab, t, &n->partial, slab_list) { > - int free = slab->objects - slab->inuse; > - > - /* Do not reread slab->inuse */ > - barrier(); > - > - /* We do not keep full slabs on the list */ > - BUG_ON(free <= 0); > - > - if (free == slab->objects) { > - list_move(&slab->slab_list, &discard); > - n->nr_partial--; > - dec_slabs_node(s, node, slab->objects); > - } else if (free <= SHRINK_PROMOTE_MAX) > - list_move(&slab->slab_list, promote + free - 1); > - } > - > - /* > - * Promote the slabs filled up most to the head of the > - * partial list. > - */ > - for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--) > - list_splice(promote + i, &n->partial); > - > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - /* Release empty slabs */ > - list_for_each_entry_safe(slab, t, &discard, slab_list) > - free_slab(s, slab); > - > - if (slabs_node(s, node)) > - ret = 1; > - } > - > - return ret; > -} > - > -int __kmem_cache_shrink(struct kmem_cache *s) > -{ > - flush_all(s); > - return __kmem_cache_do_shrink(s); > -} > - > -static int slab_mem_going_offline_callback(void *arg) > -{ > - struct kmem_cache *s; > - > - mutex_lock(&slab_mutex); > - list_for_each_entry(s, &slab_caches, list) { > - flush_all_cpus_locked(s); > - __kmem_cache_do_shrink(s); > - } > - mutex_unlock(&slab_mutex); > - > - return 0; > -} > - > -static void slab_mem_offline_callback(void *arg) > -{ > - struct memory_notify *marg = arg; > - int offline_node; > - > - offline_node = marg->status_change_nid_normal; > - > - /* > - * If the node still has available memory. we need kmem_cache_node > - * for it yet. > - */ > - if (offline_node < 0) > - return; > - > - mutex_lock(&slab_mutex); > - node_clear(offline_node, slab_nodes); > - /* > - * We no longer free kmem_cache_node structures here, as it would be > - * racy with all get_node() users, and infeasible to protect them with > - * slab_mutex. > - */ > - mutex_unlock(&slab_mutex); > -} > - > -static int slab_mem_going_online_callback(void *arg) > -{ > - struct kmem_cache_node *n; > - struct kmem_cache *s; > - struct memory_notify *marg = arg; > - int nid = marg->status_change_nid_normal; > - int ret = 0; > - > - /* > - * If the node's memory is already available, then kmem_cache_node is > - * already created. Nothing to do. > - */ > - if (nid < 0) > - return 0; > - > - /* > - * We are bringing a node online. No memory is available yet. We must > - * allocate a kmem_cache_node structure in order to bring the node > - * online. > - */ > - mutex_lock(&slab_mutex); > - list_for_each_entry(s, &slab_caches, list) { > - /* > - * The structure may already exist if the node was previously > - * onlined and offlined. > - */ > - if (get_node(s, nid)) > - continue; > - /* > - * XXX: kmem_cache_alloc_node will fallback to other nodes > - * since memory is not yet available from the node that > - * is brought up. > - */ > - n = kmem_cache_alloc(kmem_cache_node, GFP_KERNEL); > - if (!n) { > - ret = -ENOMEM; > - goto out; > - } > - init_kmem_cache_node(n); > - s->node[nid] = n; > - } > - /* > - * Any cache created after this point will also have kmem_cache_node > - * initialized for the new node. > - */ > - node_set(nid, slab_nodes); > -out: > - mutex_unlock(&slab_mutex); > - return ret; > -} > - > -static int slab_memory_callback(struct notifier_block *self, > - unsigned long action, void *arg) > -{ > - int ret = 0; > - > - switch (action) { > - case MEM_GOING_ONLINE: > - ret = slab_mem_going_online_callback(arg); > - break; > - case MEM_GOING_OFFLINE: > - ret = slab_mem_going_offline_callback(arg); > - break; > - case MEM_OFFLINE: > - case MEM_CANCEL_ONLINE: > - slab_mem_offline_callback(arg); > - break; > - case MEM_ONLINE: > - case MEM_CANCEL_OFFLINE: > - break; > - } > - if (ret) > - ret = notifier_from_errno(ret); > - else > - ret = NOTIFY_OK; > - return ret; > -} > - > -/******************************************************************** > - * Basic setup of slabs > - *******************************************************************/ > - > -/* > - * Used for early kmem_cache structures that were allocated using > - * the page allocator. Allocate them properly then fix up the pointers > - * that may be pointing to the wrong kmem_cache structure. > - */ > - > -static struct kmem_cache * __init bootstrap(struct kmem_cache *static_cache) > -{ > - int node; > - struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); > - struct kmem_cache_node *n; > - > - memcpy(s, static_cache, kmem_cache->object_size); > - > - /* > - * This runs very early, and only the boot processor is supposed to be > - * up. Even if it weren't true, IRQs are not up so we couldn't fire > - * IPIs around. > - */ > - __flush_cpu_slab(s, smp_processor_id()); > - for_each_kmem_cache_node(s, node, n) { > - struct slab *p; > - > - list_for_each_entry(p, &n->partial, slab_list) > - p->slab_cache = s; > - > -#ifdef CONFIG_SLUB_DEBUG > - list_for_each_entry(p, &n->full, slab_list) > - p->slab_cache = s; > -#endif > - } > - list_add(&s->list, &slab_caches); > - return s; > -} > - > -void __init kmem_cache_init(void) > -{ > - static __initdata struct kmem_cache boot_kmem_cache, > - boot_kmem_cache_node; > - int node; > - > - if (debug_guardpage_minorder()) > - slub_max_order = 0; > - > - /* Print slub debugging pointers without hashing */ > - if (__slub_debug_enabled()) > - no_hash_pointers_enable(NULL); > - > - kmem_cache_node = &boot_kmem_cache_node; > - kmem_cache = &boot_kmem_cache; > - > - /* > - * Initialize the nodemask for which we will allocate per node > - * structures. Here we don't need taking slab_mutex yet. > - */ > - for_each_node_state(node, N_NORMAL_MEMORY) > - node_set(node, slab_nodes); > - > - create_boot_cache(kmem_cache_node, "kmem_cache_node", > - sizeof(struct kmem_cache_node), SLAB_HWCACHE_ALIGN, 0, 0); > - > - hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI); > - > - /* Able to allocate the per node structures */ > - slab_state = PARTIAL; > - > - create_boot_cache(kmem_cache, "kmem_cache", > - offsetof(struct kmem_cache, node) + > - nr_node_ids * sizeof(struct kmem_cache_node *), > - SLAB_HWCACHE_ALIGN, 0, 0); > - > - kmem_cache = bootstrap(&boot_kmem_cache); > - kmem_cache_node = bootstrap(&boot_kmem_cache_node); > - > - /* Now we can use the kmem_cache to allocate kmalloc slabs */ > - setup_kmalloc_cache_index_table(); > - create_kmalloc_caches(0); > - > - /* Setup random freelists for each cache */ > - init_freelist_randomization(); > - > - cpuhp_setup_state_nocalls(CPUHP_SLUB_DEAD, "slub:dead", NULL, > - slub_cpu_dead); > - > - pr_info("SLUB: HWalign=%d, Order=%u-%u, MinObjects=%u, CPUs=%u, Nodes=%u\n", > - cache_line_size(), > - slub_min_order, slub_max_order, slub_min_objects, > - nr_cpu_ids, nr_node_ids); > -} > - > -void __init kmem_cache_init_late(void) > -{ > -#ifndef CONFIG_SLUB_TINY > - flushwq = alloc_workqueue("slub_flushwq", WQ_MEM_RECLAIM, 0); > - WARN_ON(!flushwq); > -#endif > -} > - > -struct kmem_cache * > -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > - slab_flags_t flags, void (*ctor)(void *)) > -{ > - struct kmem_cache *s; > - > - s = find_mergeable(size, align, flags, name, ctor); > - if (s) { > - if (sysfs_slab_alias(s, name)) > - return NULL; > - > - s->refcount++; > - > - /* > - * Adjust the object sizes so that we clear > - * the complete object on kzalloc. > - */ > - s->object_size = max(s->object_size, size); > - s->inuse = max(s->inuse, ALIGN(size, sizeof(void *))); > - } > - > - return s; > -} > - > -int __kmem_cache_create(struct kmem_cache *s, slab_flags_t flags) > -{ > - int err; > - > - err = kmem_cache_open(s, flags); > - if (err) > - return err; > - > - /* Mutex is not taken during early boot */ > - if (slab_state <= UP) > - return 0; > - > - err = sysfs_slab_add(s); > - if (err) { > - __kmem_cache_release(s); > - return err; > - } > - > - if (s->flags & SLAB_STORE_USER) > - debugfs_slab_add(s); > - > - return 0; > -} > - > -#ifdef SLAB_SUPPORTS_SYSFS > -static int count_inuse(struct slab *slab) > -{ > - return slab->inuse; > -} > - > -static int count_total(struct slab *slab) > -{ > - return slab->objects; > -} > -#endif > - > -#ifdef CONFIG_SLUB_DEBUG > -static void validate_slab(struct kmem_cache *s, struct slab *slab, > - unsigned long *obj_map) > -{ > - void *p; > - void *addr = slab_address(slab); > - > - if (!check_slab(s, slab) || !on_freelist(s, slab, NULL)) > - return; > - > - /* Now we know that a valid freelist exists */ > - __fill_map(obj_map, s, slab); > - for_each_object(p, s, addr, slab->objects) { > - u8 val = test_bit(__obj_to_index(s, addr, p), obj_map) ? > - SLUB_RED_INACTIVE : SLUB_RED_ACTIVE; > - > - if (!check_object(s, slab, p, val)) > - break; > - } > -} > - > -static int validate_slab_node(struct kmem_cache *s, > - struct kmem_cache_node *n, unsigned long *obj_map) > -{ > - unsigned long count = 0; > - struct slab *slab; > - unsigned long flags; > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - list_for_each_entry(slab, &n->partial, slab_list) { > - validate_slab(s, slab, obj_map); > - count++; > - } > - if (count != n->nr_partial) { > - pr_err("SLUB %s: %ld partial slabs counted but counter=%ld\n", > - s->name, count, n->nr_partial); > - slab_add_kunit_errors(); > - } > - > - if (!(s->flags & SLAB_STORE_USER)) > - goto out; > - > - list_for_each_entry(slab, &n->full, slab_list) { > - validate_slab(s, slab, obj_map); > - count++; > - } > - if (count != atomic_long_read(&n->nr_slabs)) { > - pr_err("SLUB: %s %ld slabs counted but counter=%ld\n", > - s->name, count, atomic_long_read(&n->nr_slabs)); > - slab_add_kunit_errors(); > - } > - > -out: > - spin_unlock_irqrestore(&n->list_lock, flags); > - return count; > -} > - > -long validate_slab_cache(struct kmem_cache *s) > -{ > - int node; > - unsigned long count = 0; > - struct kmem_cache_node *n; > - unsigned long *obj_map; > - > - obj_map = bitmap_alloc(oo_objects(s->oo), GFP_KERNEL); > - if (!obj_map) > - return -ENOMEM; > - > - flush_all(s); > - for_each_kmem_cache_node(s, node, n) > - count += validate_slab_node(s, n, obj_map); > - > - bitmap_free(obj_map); > - > - return count; > -} > -EXPORT_SYMBOL(validate_slab_cache); > - > -#ifdef CONFIG_DEBUG_FS > -/* > - * Generate lists of code addresses where slabcache objects are allocated > - * and freed. > - */ > - > -struct location { > - depot_stack_handle_t handle; > - unsigned long count; > - unsigned long addr; > - unsigned long waste; > - long long sum_time; > - long min_time; > - long max_time; > - long min_pid; > - long max_pid; > - DECLARE_BITMAP(cpus, NR_CPUS); > - nodemask_t nodes; > -}; > - > -struct loc_track { > - unsigned long max; > - unsigned long count; > - struct location *loc; > - loff_t idx; > -}; > - > -static struct dentry *slab_debugfs_root; > - > -static void free_loc_track(struct loc_track *t) > -{ > - if (t->max) > - free_pages((unsigned long)t->loc, > - get_order(sizeof(struct location) * t->max)); > -} > - > -static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags) > -{ > - struct location *l; > - int order; > - > - order = get_order(sizeof(struct location) * max); > - > - l = (void *)__get_free_pages(flags, order); > - if (!l) > - return 0; > - > - if (t->count) { > - memcpy(l, t->loc, sizeof(struct location) * t->count); > - free_loc_track(t); > - } > - t->max = max; > - t->loc = l; > - return 1; > -} > - > -static int add_location(struct loc_track *t, struct kmem_cache *s, > - const struct track *track, > - unsigned int orig_size) > -{ > - long start, end, pos; > - struct location *l; > - unsigned long caddr, chandle, cwaste; > - unsigned long age = jiffies - track->when; > - depot_stack_handle_t handle = 0; > - unsigned int waste = s->object_size - orig_size; > - > -#ifdef CONFIG_STACKDEPOT > - handle = READ_ONCE(track->handle); > -#endif > - start = -1; > - end = t->count; > - > - for ( ; ; ) { > - pos = start + (end - start + 1) / 2; > - > - /* > - * There is nothing at "end". If we end up there > - * we need to add something to before end. > - */ > - if (pos == end) > - break; > - > - l = &t->loc[pos]; > - caddr = l->addr; > - chandle = l->handle; > - cwaste = l->waste; > - if ((track->addr == caddr) && (handle == chandle) && > - (waste == cwaste)) { > - > - l->count++; > - if (track->when) { > - l->sum_time += age; > - if (age < l->min_time) > - l->min_time = age; > - if (age > l->max_time) > - l->max_time = age; > - > - if (track->pid < l->min_pid) > - l->min_pid = track->pid; > - if (track->pid > l->max_pid) > - l->max_pid = track->pid; > - > - cpumask_set_cpu(track->cpu, > - to_cpumask(l->cpus)); > - } > - node_set(page_to_nid(virt_to_page(track)), l->nodes); > - return 1; > - } > - > - if (track->addr < caddr) > - end = pos; > - else if (track->addr == caddr && handle < chandle) > - end = pos; > - else if (track->addr == caddr && handle == chandle && > - waste < cwaste) > - end = pos; > - else > - start = pos; > - } > - > - /* > - * Not found. Insert new tracking element. > - */ > - if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC)) > - return 0; > - > - l = t->loc + pos; > - if (pos < t->count) > - memmove(l + 1, l, > - (t->count - pos) * sizeof(struct location)); > - t->count++; > - l->count = 1; > - l->addr = track->addr; > - l->sum_time = age; > - l->min_time = age; > - l->max_time = age; > - l->min_pid = track->pid; > - l->max_pid = track->pid; > - l->handle = handle; > - l->waste = waste; > - cpumask_clear(to_cpumask(l->cpus)); > - cpumask_set_cpu(track->cpu, to_cpumask(l->cpus)); > - nodes_clear(l->nodes); > - node_set(page_to_nid(virt_to_page(track)), l->nodes); > - return 1; > -} > - > -static void process_slab(struct loc_track *t, struct kmem_cache *s, > - struct slab *slab, enum track_item alloc, > - unsigned long *obj_map) > -{ > - void *addr = slab_address(slab); > - bool is_alloc = (alloc == TRACK_ALLOC); > - void *p; > - > - __fill_map(obj_map, s, slab); > - > - for_each_object(p, s, addr, slab->objects) > - if (!test_bit(__obj_to_index(s, addr, p), obj_map)) > - add_location(t, s, get_track(s, p, alloc), > - is_alloc ? get_orig_size(s, p) : > - s->object_size); > -} > -#endif /* CONFIG_DEBUG_FS */ > -#endif /* CONFIG_SLUB_DEBUG */ > - > -#ifdef SLAB_SUPPORTS_SYSFS > -enum slab_stat_type { > - SL_ALL, /* All slabs */ > - SL_PARTIAL, /* Only partially allocated slabs */ > - SL_CPU, /* Only slabs used for cpu caches */ > - SL_OBJECTS, /* Determine allocated objects not slabs */ > - SL_TOTAL /* Determine object capacity not slabs */ > -}; > - > -#define SO_ALL (1 << SL_ALL) > -#define SO_PARTIAL (1 << SL_PARTIAL) > -#define SO_CPU (1 << SL_CPU) > -#define SO_OBJECTS (1 << SL_OBJECTS) > -#define SO_TOTAL (1 << SL_TOTAL) > - > -static ssize_t show_slab_objects(struct kmem_cache *s, > - char *buf, unsigned long flags) > -{ > - unsigned long total = 0; > - int node; > - int x; > - unsigned long *nodes; > - int len = 0; > - > - nodes = kcalloc(nr_node_ids, sizeof(unsigned long), GFP_KERNEL); > - if (!nodes) > - return -ENOMEM; > - > - if (flags & SO_CPU) { > - int cpu; > - > - for_each_possible_cpu(cpu) { > - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, > - cpu); > - int node; > - struct slab *slab; > - > - slab = READ_ONCE(c->slab); > - if (!slab) > - continue; > - > - node = slab_nid(slab); > - if (flags & SO_TOTAL) > - x = slab->objects; > - else if (flags & SO_OBJECTS) > - x = slab->inuse; > - else > - x = 1; > - > - total += x; > - nodes[node] += x; > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - slab = slub_percpu_partial_read_once(c); > - if (slab) { > - node = slab_nid(slab); > - if (flags & SO_TOTAL) > - WARN_ON_ONCE(1); > - else if (flags & SO_OBJECTS) > - WARN_ON_ONCE(1); > - else > - x = slab->slabs; > - total += x; > - nodes[node] += x; > - } > -#endif > - } > - } > - > - /* > - * It is impossible to take "mem_hotplug_lock" here with "kernfs_mutex" > - * already held which will conflict with an existing lock order: > - * > - * mem_hotplug_lock->slab_mutex->kernfs_mutex > - * > - * We don't really need mem_hotplug_lock (to hold off > - * slab_mem_going_offline_callback) here because slab's memory hot > - * unplug code doesn't destroy the kmem_cache->node[] data. > - */ > - > -#ifdef CONFIG_SLUB_DEBUG > - if (flags & SO_ALL) { > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - > - if (flags & SO_TOTAL) > - x = atomic_long_read(&n->total_objects); > - else if (flags & SO_OBJECTS) > - x = atomic_long_read(&n->total_objects) - > - count_partial(n, count_free); > - else > - x = atomic_long_read(&n->nr_slabs); > - total += x; > - nodes[node] += x; > - } > - > - } else > -#endif > - if (flags & SO_PARTIAL) { > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - if (flags & SO_TOTAL) > - x = count_partial(n, count_total); > - else if (flags & SO_OBJECTS) > - x = count_partial(n, count_inuse); > - else > - x = n->nr_partial; > - total += x; > - nodes[node] += x; > - } > - } > - > - len += sysfs_emit_at(buf, len, "%lu", total); > -#ifdef CONFIG_NUMA > - for (node = 0; node < nr_node_ids; node++) { > - if (nodes[node]) > - len += sysfs_emit_at(buf, len, " N%d=%lu", > - node, nodes[node]); > - } > -#endif > - len += sysfs_emit_at(buf, len, "\n"); > - kfree(nodes); > - > - return len; > -} > - > -#define to_slab_attr(n) container_of(n, struct slab_attribute, attr) > -#define to_slab(n) container_of(n, struct kmem_cache, kobj) > - > -struct slab_attribute { > - struct attribute attr; > - ssize_t (*show)(struct kmem_cache *s, char *buf); > - ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count); > -}; > - > -#define SLAB_ATTR_RO(_name) \ > - static struct slab_attribute _name##_attr = __ATTR_RO_MODE(_name, 0400) > - > -#define SLAB_ATTR(_name) \ > - static struct slab_attribute _name##_attr = __ATTR_RW_MODE(_name, 0600) > - > -static ssize_t slab_size_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->size); > -} > -SLAB_ATTR_RO(slab_size); > - > -static ssize_t align_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->align); > -} > -SLAB_ATTR_RO(align); > - > -static ssize_t object_size_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->object_size); > -} > -SLAB_ATTR_RO(object_size); > - > -static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", oo_objects(s->oo)); > -} > -SLAB_ATTR_RO(objs_per_slab); > - > -static ssize_t order_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", oo_order(s->oo)); > -} > -SLAB_ATTR_RO(order); > - > -static ssize_t min_partial_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%lu\n", s->min_partial); > -} > - > -static ssize_t min_partial_store(struct kmem_cache *s, const char *buf, > - size_t length) > -{ > - unsigned long min; > - int err; > - > - err = kstrtoul(buf, 10, &min); > - if (err) > - return err; > - > - s->min_partial = min; > - return length; > -} > -SLAB_ATTR(min_partial); > - > -static ssize_t cpu_partial_show(struct kmem_cache *s, char *buf) > -{ > - unsigned int nr_partial = 0; > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - nr_partial = s->cpu_partial; > -#endif > - > - return sysfs_emit(buf, "%u\n", nr_partial); > -} > - > -static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf, > - size_t length) > -{ > - unsigned int objects; > - int err; > - > - err = kstrtouint(buf, 10, &objects); > - if (err) > - return err; > - if (objects && !kmem_cache_has_cpu_partial(s)) > - return -EINVAL; > - > - slub_set_cpu_partial(s, objects); > - flush_all(s); > - return length; > -} > -SLAB_ATTR(cpu_partial); > - > -static ssize_t ctor_show(struct kmem_cache *s, char *buf) > -{ > - if (!s->ctor) > - return 0; > - return sysfs_emit(buf, "%pS\n", s->ctor); > -} > -SLAB_ATTR_RO(ctor); > - > -static ssize_t aliases_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", s->refcount < 0 ? 0 : s->refcount - 1); > -} > -SLAB_ATTR_RO(aliases); > - > -static ssize_t partial_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_PARTIAL); > -} > -SLAB_ATTR_RO(partial); > - > -static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_CPU); > -} > -SLAB_ATTR_RO(cpu_slabs); > - > -static ssize_t objects_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS); > -} > -SLAB_ATTR_RO(objects); > - > -static ssize_t objects_partial_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS); > -} > -SLAB_ATTR_RO(objects_partial); > - > -static ssize_t slabs_cpu_partial_show(struct kmem_cache *s, char *buf) > -{ > - int objects = 0; > - int slabs = 0; > - int cpu __maybe_unused; > - int len = 0; > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - for_each_online_cpu(cpu) { > - struct slab *slab; > - > - slab = slub_percpu_partial(per_cpu_ptr(s->cpu_slab, cpu)); > - > - if (slab) > - slabs += slab->slabs; > - } > -#endif > - > - /* Approximate half-full slabs, see slub_set_cpu_partial() */ > - objects = (slabs * oo_objects(s->oo)) / 2; > - len += sysfs_emit_at(buf, len, "%d(%d)", objects, slabs); > - > -#if defined(CONFIG_SLUB_CPU_PARTIAL) && defined(CONFIG_SMP) > - for_each_online_cpu(cpu) { > - struct slab *slab; > - > - slab = slub_percpu_partial(per_cpu_ptr(s->cpu_slab, cpu)); > - if (slab) { > - slabs = READ_ONCE(slab->slabs); > - objects = (slabs * oo_objects(s->oo)) / 2; > - len += sysfs_emit_at(buf, len, " C%d=%d(%d)", > - cpu, objects, slabs); > - } > - } > -#endif > - len += sysfs_emit_at(buf, len, "\n"); > - > - return len; > -} > -SLAB_ATTR_RO(slabs_cpu_partial); > - > -static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT)); > -} > -SLAB_ATTR_RO(reclaim_account); > - > -static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN)); > -} > -SLAB_ATTR_RO(hwcache_align); > - > -#ifdef CONFIG_ZONE_DMA > -static ssize_t cache_dma_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA)); > -} > -SLAB_ATTR_RO(cache_dma); > -#endif > - > -#ifdef CONFIG_HARDENED_USERCOPY > -static ssize_t usersize_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->usersize); > -} > -SLAB_ATTR_RO(usersize); > -#endif > - > -static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_TYPESAFE_BY_RCU)); > -} > -SLAB_ATTR_RO(destroy_by_rcu); > - > -#ifdef CONFIG_SLUB_DEBUG > -static ssize_t slabs_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_ALL); > -} > -SLAB_ATTR_RO(slabs); > - > -static ssize_t total_objects_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_ALL|SO_TOTAL); > -} > -SLAB_ATTR_RO(total_objects); > - > -static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_CONSISTENCY_CHECKS)); > -} > -SLAB_ATTR_RO(sanity_checks); > - > -static ssize_t trace_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_TRACE)); > -} > -SLAB_ATTR_RO(trace); > - > -static ssize_t red_zone_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE)); > -} > - > -SLAB_ATTR_RO(red_zone); > - > -static ssize_t poison_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_POISON)); > -} > - > -SLAB_ATTR_RO(poison); > - > -static ssize_t store_user_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_STORE_USER)); > -} > - > -SLAB_ATTR_RO(store_user); > - > -static ssize_t validate_show(struct kmem_cache *s, char *buf) > -{ > - return 0; > -} > - > -static ssize_t validate_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - int ret = -EINVAL; > - > - if (buf[0] == '1' && kmem_cache_debug(s)) { > - ret = validate_slab_cache(s); > - if (ret >= 0) > - ret = length; > - } > - return ret; > -} > -SLAB_ATTR(validate); > - > -#endif /* CONFIG_SLUB_DEBUG */ > - > -#ifdef CONFIG_FAILSLAB > -static ssize_t failslab_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB)); > -} > - > -static ssize_t failslab_store(struct kmem_cache *s, const char *buf, > - size_t length) > -{ > - if (s->refcount > 1) > - return -EINVAL; > - > - if (buf[0] == '1') > - WRITE_ONCE(s->flags, s->flags | SLAB_FAILSLAB); > - else > - WRITE_ONCE(s->flags, s->flags & ~SLAB_FAILSLAB); > - > - return length; > -} > -SLAB_ATTR(failslab); > -#endif > - > -static ssize_t shrink_show(struct kmem_cache *s, char *buf) > -{ > - return 0; > -} > - > -static ssize_t shrink_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - if (buf[0] == '1') > - kmem_cache_shrink(s); > - else > - return -EINVAL; > - return length; > -} > -SLAB_ATTR(shrink); > - > -#ifdef CONFIG_NUMA > -static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->remote_node_defrag_ratio / 10); > -} > - > -static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - unsigned int ratio; > - int err; > - > - err = kstrtouint(buf, 10, &ratio); > - if (err) > - return err; > - if (ratio > 100) > - return -ERANGE; > - > - s->remote_node_defrag_ratio = ratio * 10; > - > - return length; > -} > -SLAB_ATTR(remote_node_defrag_ratio); > -#endif > - > -#ifdef CONFIG_SLUB_STATS > -static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si) > -{ > - unsigned long sum = 0; > - int cpu; > - int len = 0; > - int *data = kmalloc_array(nr_cpu_ids, sizeof(int), GFP_KERNEL); > - > - if (!data) > - return -ENOMEM; > - > - for_each_online_cpu(cpu) { > - unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si]; > - > - data[cpu] = x; > - sum += x; > - } > - > - len += sysfs_emit_at(buf, len, "%lu", sum); > - > -#ifdef CONFIG_SMP > - for_each_online_cpu(cpu) { > - if (data[cpu]) > - len += sysfs_emit_at(buf, len, " C%d=%u", > - cpu, data[cpu]); > - } > -#endif > - kfree(data); > - len += sysfs_emit_at(buf, len, "\n"); > - > - return len; > -} > - > -static void clear_stat(struct kmem_cache *s, enum stat_item si) > -{ > - int cpu; > - > - for_each_online_cpu(cpu) > - per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0; > -} > - > -#define STAT_ATTR(si, text) \ > -static ssize_t text##_show(struct kmem_cache *s, char *buf) \ > -{ \ > - return show_stat(s, buf, si); \ > -} \ > -static ssize_t text##_store(struct kmem_cache *s, \ > - const char *buf, size_t length) \ > -{ \ > - if (buf[0] != '0') \ > - return -EINVAL; \ > - clear_stat(s, si); \ > - return length; \ > -} \ > -SLAB_ATTR(text); \ > - > -STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath); > -STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath); > -STAT_ATTR(FREE_FASTPATH, free_fastpath); > -STAT_ATTR(FREE_SLOWPATH, free_slowpath); > -STAT_ATTR(FREE_FROZEN, free_frozen); > -STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial); > -STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial); > -STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial); > -STAT_ATTR(ALLOC_SLAB, alloc_slab); > -STAT_ATTR(ALLOC_REFILL, alloc_refill); > -STAT_ATTR(ALLOC_NODE_MISMATCH, alloc_node_mismatch); > -STAT_ATTR(FREE_SLAB, free_slab); > -STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush); > -STAT_ATTR(DEACTIVATE_FULL, deactivate_full); > -STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty); > -STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head); > -STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail); > -STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees); > -STAT_ATTR(DEACTIVATE_BYPASS, deactivate_bypass); > -STAT_ATTR(ORDER_FALLBACK, order_fallback); > -STAT_ATTR(CMPXCHG_DOUBLE_CPU_FAIL, cmpxchg_double_cpu_fail); > -STAT_ATTR(CMPXCHG_DOUBLE_FAIL, cmpxchg_double_fail); > -STAT_ATTR(CPU_PARTIAL_ALLOC, cpu_partial_alloc); > -STAT_ATTR(CPU_PARTIAL_FREE, cpu_partial_free); > -STAT_ATTR(CPU_PARTIAL_NODE, cpu_partial_node); > -STAT_ATTR(CPU_PARTIAL_DRAIN, cpu_partial_drain); > -#endif /* CONFIG_SLUB_STATS */ > - > -#ifdef CONFIG_KFENCE > -static ssize_t skip_kfence_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_SKIP_KFENCE)); > -} > - > -static ssize_t skip_kfence_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - int ret = length; > - > - if (buf[0] == '0') > - s->flags &= ~SLAB_SKIP_KFENCE; > - else if (buf[0] == '1') > - s->flags |= SLAB_SKIP_KFENCE; > - else > - ret = -EINVAL; > - > - return ret; > -} > -SLAB_ATTR(skip_kfence); > -#endif > - > -static struct attribute *slab_attrs[] = { > - &slab_size_attr.attr, > - &object_size_attr.attr, > - &objs_per_slab_attr.attr, > - &order_attr.attr, > - &min_partial_attr.attr, > - &cpu_partial_attr.attr, > - &objects_attr.attr, > - &objects_partial_attr.attr, > - &partial_attr.attr, > - &cpu_slabs_attr.attr, > - &ctor_attr.attr, > - &aliases_attr.attr, > - &align_attr.attr, > - &hwcache_align_attr.attr, > - &reclaim_account_attr.attr, > - &destroy_by_rcu_attr.attr, > - &shrink_attr.attr, > - &slabs_cpu_partial_attr.attr, > -#ifdef CONFIG_SLUB_DEBUG > - &total_objects_attr.attr, > - &slabs_attr.attr, > - &sanity_checks_attr.attr, > - &trace_attr.attr, > - &red_zone_attr.attr, > - &poison_attr.attr, > - &store_user_attr.attr, > - &validate_attr.attr, > -#endif > -#ifdef CONFIG_ZONE_DMA > - &cache_dma_attr.attr, > -#endif > -#ifdef CONFIG_NUMA > - &remote_node_defrag_ratio_attr.attr, > -#endif > -#ifdef CONFIG_SLUB_STATS > - &alloc_fastpath_attr.attr, > - &alloc_slowpath_attr.attr, > - &free_fastpath_attr.attr, > - &free_slowpath_attr.attr, > - &free_frozen_attr.attr, > - &free_add_partial_attr.attr, > - &free_remove_partial_attr.attr, > - &alloc_from_partial_attr.attr, > - &alloc_slab_attr.attr, > - &alloc_refill_attr.attr, > - &alloc_node_mismatch_attr.attr, > - &free_slab_attr.attr, > - &cpuslab_flush_attr.attr, > - &deactivate_full_attr.attr, > - &deactivate_empty_attr.attr, > - &deactivate_to_head_attr.attr, > - &deactivate_to_tail_attr.attr, > - &deactivate_remote_frees_attr.attr, > - &deactivate_bypass_attr.attr, > - &order_fallback_attr.attr, > - &cmpxchg_double_fail_attr.attr, > - &cmpxchg_double_cpu_fail_attr.attr, > - &cpu_partial_alloc_attr.attr, > - &cpu_partial_free_attr.attr, > - &cpu_partial_node_attr.attr, > - &cpu_partial_drain_attr.attr, > -#endif > -#ifdef CONFIG_FAILSLAB > - &failslab_attr.attr, > -#endif > -#ifdef CONFIG_HARDENED_USERCOPY > - &usersize_attr.attr, > -#endif > -#ifdef CONFIG_KFENCE > - &skip_kfence_attr.attr, > -#endif > - > - NULL > -}; > - > -static const struct attribute_group slab_attr_group = { > - .attrs = slab_attrs, > -}; > - > -static ssize_t slab_attr_show(struct kobject *kobj, > - struct attribute *attr, > - char *buf) > -{ > - struct slab_attribute *attribute; > - struct kmem_cache *s; > - > - attribute = to_slab_attr(attr); > - s = to_slab(kobj); > - > - if (!attribute->show) > - return -EIO; > - > - return attribute->show(s, buf); > -} > - > -static ssize_t slab_attr_store(struct kobject *kobj, > - struct attribute *attr, > - const char *buf, size_t len) > -{ > - struct slab_attribute *attribute; > - struct kmem_cache *s; > - > - attribute = to_slab_attr(attr); > - s = to_slab(kobj); > - > - if (!attribute->store) > - return -EIO; > - > - return attribute->store(s, buf, len); > -} > - > -static void kmem_cache_release(struct kobject *k) > -{ > - slab_kmem_cache_release(to_slab(k)); > -} > - > -static const struct sysfs_ops slab_sysfs_ops = { > - .show = slab_attr_show, > - .store = slab_attr_store, > -}; > - > -static struct kobj_type slab_ktype = { > - .sysfs_ops = &slab_sysfs_ops, > - .release = kmem_cache_release, > -}; > - > -static struct kset *slab_kset; > - > -static inline struct kset *cache_kset(struct kmem_cache *s) > -{ > - return slab_kset; > -} > - > -#define ID_STR_LENGTH 32 > - > -/* Create a unique string id for a slab cache: > - * > - * Format :[flags-]size > - */ > -static char *create_unique_id(struct kmem_cache *s) > -{ > - char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL); > - char *p = name; > - > - if (!name) > - return ERR_PTR(-ENOMEM); > - > - *p++ = ':'; > - /* > - * First flags affecting slabcache operations. We will only > - * get here for aliasable slabs so we do not need to support > - * too many flags. The flags here must cover all flags that > - * are matched during merging to guarantee that the id is > - * unique. > - */ > - if (s->flags & SLAB_CACHE_DMA) > - *p++ = 'd'; > - if (s->flags & SLAB_CACHE_DMA32) > - *p++ = 'D'; > - if (s->flags & SLAB_RECLAIM_ACCOUNT) > - *p++ = 'a'; > - if (s->flags & SLAB_CONSISTENCY_CHECKS) > - *p++ = 'F'; > - if (s->flags & SLAB_ACCOUNT) > - *p++ = 'A'; > - if (p != name + 1) > - *p++ = '-'; > - p += snprintf(p, ID_STR_LENGTH - (p - name), "%07u", s->size); > - > - if (WARN_ON(p > name + ID_STR_LENGTH - 1)) { > - kfree(name); > - return ERR_PTR(-EINVAL); > - } > - kmsan_unpoison_memory(name, p - name); > - return name; > -} > - > -static int sysfs_slab_add(struct kmem_cache *s) > -{ > - int err; > - const char *name; > - struct kset *kset = cache_kset(s); > - int unmergeable = slab_unmergeable(s); > - > - if (!unmergeable && disable_higher_order_debug && > - (slub_debug & DEBUG_METADATA_FLAGS)) > - unmergeable = 1; > - > - if (unmergeable) { > - /* > - * Slabcache can never be merged so we can use the name proper. > - * This is typically the case for debug situations. In that > - * case we can catch duplicate names easily. > - */ > - sysfs_remove_link(&slab_kset->kobj, s->name); > - name = s->name; > - } else { > - /* > - * Create a unique name for the slab as a target > - * for the symlinks. > - */ > - name = create_unique_id(s); > - if (IS_ERR(name)) > - return PTR_ERR(name); > - } > - > - s->kobj.kset = kset; > - err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, "%s", name); > - if (err) > - goto out; > - > - err = sysfs_create_group(&s->kobj, &slab_attr_group); > - if (err) > - goto out_del_kobj; > - > - if (!unmergeable) { > - /* Setup first alias */ > - sysfs_slab_alias(s, s->name); > - } > -out: > - if (!unmergeable) > - kfree(name); > - return err; > -out_del_kobj: > - kobject_del(&s->kobj); > - goto out; > -} > - > -void sysfs_slab_unlink(struct kmem_cache *s) > -{ > - if (slab_state >= FULL) > - kobject_del(&s->kobj); > -} > - > -void sysfs_slab_release(struct kmem_cache *s) > -{ > - if (slab_state >= FULL) > - kobject_put(&s->kobj); > -} > - > -/* > - * Need to buffer aliases during bootup until sysfs becomes > - * available lest we lose that information. > - */ > -struct saved_alias { > - struct kmem_cache *s; > - const char *name; > - struct saved_alias *next; > -}; > - > -static struct saved_alias *alias_list; > - > -static int sysfs_slab_alias(struct kmem_cache *s, const char *name) > -{ > - struct saved_alias *al; > - > - if (slab_state == FULL) { > - /* > - * If we have a leftover link then remove it. > - */ > - sysfs_remove_link(&slab_kset->kobj, name); > - return sysfs_create_link(&slab_kset->kobj, &s->kobj, name); > - } > - > - al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL); > - if (!al) > - return -ENOMEM; > - > - al->s = s; > - al->name = name; > - al->next = alias_list; > - alias_list = al; > - kmsan_unpoison_memory(al, sizeof(*al)); > - return 0; > -} > - > -static int __init slab_sysfs_init(void) > -{ > - struct kmem_cache *s; > - int err; > - > - mutex_lock(&slab_mutex); > - > - slab_kset = kset_create_and_add("slab", NULL, kernel_kobj); > - if (!slab_kset) { > - mutex_unlock(&slab_mutex); > - pr_err("Cannot register slab subsystem.\n"); > - return -ENOSYS; > - } > - > - slab_state = FULL; > - > - list_for_each_entry(s, &slab_caches, list) { > - err = sysfs_slab_add(s); > - if (err) > - pr_err("SLUB: Unable to add boot slab %s to sysfs\n", > - s->name); > - } > - > - while (alias_list) { > - struct saved_alias *al = alias_list; > - > - alias_list = alias_list->next; > - err = sysfs_slab_alias(al->s, al->name); > - if (err) > - pr_err("SLUB: Unable to add boot slab alias %s to sysfs\n", > - al->name); > - kfree(al); > - } > - > - mutex_unlock(&slab_mutex); > - return 0; > -} > -late_initcall(slab_sysfs_init); > -#endif /* SLAB_SUPPORTS_SYSFS */ > - > -#if defined(CONFIG_SLUB_DEBUG) && defined(CONFIG_DEBUG_FS) > -static int slab_debugfs_show(struct seq_file *seq, void *v) > -{ > - struct loc_track *t = seq->private; > - struct location *l; > - unsigned long idx; > - > - idx = (unsigned long) t->idx; > - if (idx < t->count) { > - l = &t->loc[idx]; > - > - seq_printf(seq, "%7ld ", l->count); > - > - if (l->addr) > - seq_printf(seq, "%pS", (void *)l->addr); > - else > - seq_puts(seq, "<not-available>"); > - > - if (l->waste) > - seq_printf(seq, " waste=%lu/%lu", > - l->count * l->waste, l->waste); > - > - if (l->sum_time != l->min_time) { > - seq_printf(seq, " age=%ld/%llu/%ld", > - l->min_time, div_u64(l->sum_time, l->count), > - l->max_time); > - } else > - seq_printf(seq, " age=%ld", l->min_time); > - > - if (l->min_pid != l->max_pid) > - seq_printf(seq, " pid=%ld-%ld", l->min_pid, l->max_pid); > - else > - seq_printf(seq, " pid=%ld", > - l->min_pid); > - > - if (num_online_cpus() > 1 && !cpumask_empty(to_cpumask(l->cpus))) > - seq_printf(seq, " cpus=%*pbl", > - cpumask_pr_args(to_cpumask(l->cpus))); > - > - if (nr_online_nodes > 1 && !nodes_empty(l->nodes)) > - seq_printf(seq, " nodes=%*pbl", > - nodemask_pr_args(&l->nodes)); > - > -#ifdef CONFIG_STACKDEPOT > - { > - depot_stack_handle_t handle; > - unsigned long *entries; > - unsigned int nr_entries, j; > - > - handle = READ_ONCE(l->handle); > - if (handle) { > - nr_entries = stack_depot_fetch(handle, &entries); > - seq_puts(seq, "\n"); > - for (j = 0; j < nr_entries; j++) > - seq_printf(seq, " %pS\n", (void *)entries[j]); > - } > - } > -#endif > - seq_puts(seq, "\n"); > - } > - > - if (!idx && !t->count) > - seq_puts(seq, "No data\n"); > - > - return 0; > -} > - > -static void slab_debugfs_stop(struct seq_file *seq, void *v) > -{ > -} > - > -static void *slab_debugfs_next(struct seq_file *seq, void *v, loff_t *ppos) > -{ > - struct loc_track *t = seq->private; > - > - t->idx = ++(*ppos); > - if (*ppos <= t->count) > - return ppos; > - > - return NULL; > -} > - > -static int cmp_loc_by_count(const void *a, const void *b, const void *data) > -{ > - struct location *loc1 = (struct location *)a; > - struct location *loc2 = (struct location *)b; > - > - if (loc1->count > loc2->count) > - return -1; > - else > - return 1; > -} > - > -static void *slab_debugfs_start(struct seq_file *seq, loff_t *ppos) > -{ > - struct loc_track *t = seq->private; > - > - t->idx = *ppos; > - return ppos; > -} > - > -static const struct seq_operations slab_debugfs_sops = { > - .start = slab_debugfs_start, > - .next = slab_debugfs_next, > - .stop = slab_debugfs_stop, > - .show = slab_debugfs_show, > -}; > - > -static int slab_debug_trace_open(struct inode *inode, struct file *filep) > -{ > - > - struct kmem_cache_node *n; > - enum track_item alloc; > - int node; > - struct loc_track *t = __seq_open_private(filep, &slab_debugfs_sops, > - sizeof(struct loc_track)); > - struct kmem_cache *s = file_inode(filep)->i_private; > - unsigned long *obj_map; > - > - if (!t) > - return -ENOMEM; > - > - obj_map = bitmap_alloc(oo_objects(s->oo), GFP_KERNEL); > - if (!obj_map) { > - seq_release_private(inode, filep); > - return -ENOMEM; > - } > - > - if (strcmp(filep->f_path.dentry->d_name.name, "alloc_traces") == 0) > - alloc = TRACK_ALLOC; > - else > - alloc = TRACK_FREE; > - > - if (!alloc_loc_track(t, PAGE_SIZE / sizeof(struct location), GFP_KERNEL)) { > - bitmap_free(obj_map); > - seq_release_private(inode, filep); > - return -ENOMEM; > - } > - > - for_each_kmem_cache_node(s, node, n) { > - unsigned long flags; > - struct slab *slab; > - > - if (!atomic_long_read(&n->nr_slabs)) > - continue; > - > - spin_lock_irqsave(&n->list_lock, flags); > - list_for_each_entry(slab, &n->partial, slab_list) > - process_slab(t, s, slab, alloc, obj_map); > - list_for_each_entry(slab, &n->full, slab_list) > - process_slab(t, s, slab, alloc, obj_map); > - spin_unlock_irqrestore(&n->list_lock, flags); > - } > - > - /* Sort locations by count */ > - sort_r(t->loc, t->count, sizeof(struct location), > - cmp_loc_by_count, NULL, NULL); > - > - bitmap_free(obj_map); > - return 0; > -} > - > -static int slab_debug_trace_release(struct inode *inode, struct file *file) > -{ > - struct seq_file *seq = file->private_data; > - struct loc_track *t = seq->private; > - > - free_loc_track(t); > - return seq_release_private(inode, file); > -} > - > -static const struct file_operations slab_debugfs_fops = { > - .open = slab_debug_trace_open, > - .read = seq_read, > - .llseek = seq_lseek, > - .release = slab_debug_trace_release, > -}; > - > -static void debugfs_slab_add(struct kmem_cache *s) > -{ > - struct dentry *slab_cache_dir; > - > - if (unlikely(!slab_debugfs_root)) > - return; > - > - slab_cache_dir = debugfs_create_dir(s->name, slab_debugfs_root); > - > - debugfs_create_file("alloc_traces", 0400, > - slab_cache_dir, s, &slab_debugfs_fops); > - > - debugfs_create_file("free_traces", 0400, > - slab_cache_dir, s, &slab_debugfs_fops); > -} > - > -void debugfs_slab_release(struct kmem_cache *s) > -{ > - debugfs_lookup_and_remove(s->name, slab_debugfs_root); > -} > - > -static int __init slab_debugfs_init(void) > -{ > - struct kmem_cache *s; > - > - slab_debugfs_root = debugfs_create_dir("slab", NULL); > - > - list_for_each_entry(s, &slab_caches, list) > - if (s->flags & SLAB_STORE_USER) > - debugfs_slab_add(s); > - > - return 0; > - > -} > -__initcall(slab_debugfs_init); > -#endif > -/* > - * The /proc/slabinfo ABI > - */ > -#ifdef CONFIG_SLUB_DEBUG > -void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo) > -{ > - unsigned long nr_slabs = 0; > - unsigned long nr_objs = 0; > - unsigned long nr_free = 0; > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - nr_slabs += node_nr_slabs(n); > - nr_objs += node_nr_objs(n); > - nr_free += count_partial(n, count_free); > - } > - > - sinfo->active_objs = nr_objs - nr_free; > - sinfo->num_objs = nr_objs; > - sinfo->active_slabs = nr_slabs; > - sinfo->num_slabs = nr_slabs; > - sinfo->objects_per_slab = oo_objects(s->oo); > - sinfo->cache_order = oo_order(s->oo); > -} > - > -void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s) > -{ > -} > - > -ssize_t slabinfo_write(struct file *file, const char __user *buffer, > - size_t count, loff_t *ppos) > -{ > - return -EIO; > -} > -#endif /* CONFIG_SLUB_DEBUG */ > -- > 2.40.0 > >
It's a trap! I read it as a desperate attempt by manufacturers of memory modules to cause an artifical increase in demand, thus recovering DRAM prices. Sorry for top-posting. Petr T On Sat, 1 Apr 2023 11:46:58 +0200 Vlastimil Babka <vbabka@suse.cz> wrote: > As the SLOB removal is on track and the SLAB removal is planned, I have > realized - why should we stop there and not remove also SLUB? What's a > slab allocator good for in 2023? The RAM sizes are getting larger and > the modules cheaper [1]. The object constructor trick was perhaps > interesting in 1994, but not with contemporary CPUs. So all the slab > allocator does today is just adding an unnecessary layer of complexity > over the page allocator. > > Thus, with this patch, all three slab allocators are removed, and only a > layer that passes everything to the page allocator remains in the slab.h > and mm/slab_common.c files. This will allow users to gradually > transition away and use the page allocator directly. To summarize the > advantages: > > - Less code to maintain: over 13k lines are removed by this patch, and > more could be removed if I wast^Wspent more time on this, and later as > users are transitioned from the legacy layer. This no longer needs a > separate subsystem so remove it from MAINTAINERS (I hope I can keep the > kernel.org account anyway, though). > > - Simplified MEMCG_KMEM accounting: while I was lazy and just marked it > BROKEN in this patch, it should be trivial to use the page memcg > accounting now that we use the page allocator. The per-object > accounting went through several iterations in the past and was always > complex and added overhead. Page accounting is much simpler by > comparison. > > - Simplified KASAN and friends: also was lazy in this patch so they > can't be enabled but should be easy to fix up and work just on the > page level. > > - Simpler debugging: just use debug_pagealloc=on, no need to look up the > exact syntax of the absurdly complex slub_debug parameter. > > - Speed: didn't measure, but for the page allocator we have pcplists, so > it should scale just fine. No need for the crazy SLUB's cmpxchg_double() > craziness. Maybe that thing could be now removed too? Yeah I can see > just two remaining users. > > Any downsides? Let's look at memory usage after virtme boot: > > Before (with SLUB): > Slab: 26304 kB > > After: > Slab: 295592 kB > > Well, that's not so bad, see [1]. > > [1] https://www.theregister.com/2023/03/29/dram_prices_crash/ > --- > MAINTAINERS | 15 - > include/linux/slab.h | 211 +- > include/linux/slab_def.h | 124 - > include/linux/slub_def.h | 198 -- > init/Kconfig | 2 +- > mm/Kconfig | 134 +- > mm/Makefile | 10 - > mm/slab.c | 4046 ------------------------ > mm/slab.h | 426 --- > mm/slab_common.c | 876 ++--- > mm/slob.c | 757 ----- > mm/slub.c | 6506 -------------------------------------- > 12 files changed, 228 insertions(+), 13077 deletions(-) > delete mode 100644 include/linux/slab_def.h > delete mode 100644 include/linux/slub_def.h > delete mode 100644 mm/slab.c > delete mode 100644 mm/slob.c > delete mode 100644 mm/slub.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 1dc8bd26b6cf..40b05ad03cd0 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -19183,21 +19183,6 @@ F: drivers/irqchip/irq-sl28cpld.c > F: drivers/pwm/pwm-sl28cpld.c > F: drivers/watchdog/sl28cpld_wdt.c > > -SLAB ALLOCATOR > -M: Christoph Lameter <cl@linux.com> > -M: Pekka Enberg <penberg@kernel.org> > -M: David Rientjes <rientjes@google.com> > -M: Joonsoo Kim <iamjoonsoo.kim@lge.com> > -M: Andrew Morton <akpm@linux-foundation.org> > -M: Vlastimil Babka <vbabka@suse.cz> > -R: Roman Gushchin <roman.gushchin@linux.dev> > -R: Hyeonggon Yoo <42.hyeyoo@gmail.com> > -L: linux-mm@kvack.org > -S: Maintained > -T: git git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab.git > -F: include/linux/sl?b*.h > -F: mm/sl?b* > - > SLCAN CAN NETWORK DRIVER > M: Dario Binacchi <dario.binacchi@amarulasolutions.com> > L: linux-can@vger.kernel.org > diff --git a/include/linux/slab.h b/include/linux/slab.h > index 45af70315a94..61602d54b1d0 100644 > --- a/include/linux/slab.h > +++ b/include/linux/slab.h > @@ -140,13 +140,14 @@ > > /* The following flags affect the page allocator grouping pages by mobility */ > /* Objects are reclaimable */ > -#ifndef CONFIG_SLUB_TINY > #define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U) > -#else > -#define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0) > -#endif > #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */ > > +#define KMALLOC_NOT_NORMAL_BITS \ > + (__GFP_RECLAIMABLE | \ > + (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ > + (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) > + > /* > * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests. > * > @@ -278,38 +279,11 @@ static inline unsigned int arch_slab_minalign(void) > * Kmalloc array related definitions > */ > > -#ifdef CONFIG_SLAB > -/* > - * SLAB and SLUB directly allocates requests fitting in to an order-1 page > - * (PAGE_SIZE*2). Larger requests are passed to the page allocator. > - */ > -#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) > -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > -#ifndef KMALLOC_SHIFT_LOW > -#define KMALLOC_SHIFT_LOW 5 > -#endif > -#endif > - > -#ifdef CONFIG_SLUB > -#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) > -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > -#ifndef KMALLOC_SHIFT_LOW > -#define KMALLOC_SHIFT_LOW 3 > -#endif > -#endif > - > -#ifdef CONFIG_SLOB > -/* > - * SLOB passes all requests larger than one page to the page allocator. > - * No kmalloc array is necessary since objects of different sizes can > - * be allocated from the same page. > - */ > #define KMALLOC_SHIFT_HIGH PAGE_SHIFT > #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > #ifndef KMALLOC_SHIFT_LOW > #define KMALLOC_SHIFT_LOW 3 > #endif > -#endif > > /* Maximum allocatable size */ > #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX) > @@ -336,130 +310,6 @@ static inline unsigned int arch_slab_minalign(void) > #define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \ > (KMALLOC_MIN_SIZE) : 16) > > -/* > - * Whenever changing this, take care of that kmalloc_type() and > - * create_kmalloc_caches() still work as intended. > - * > - * KMALLOC_NORMAL can contain only unaccounted objects whereas KMALLOC_CGROUP > - * is for accounted but unreclaimable and non-dma objects. All the other > - * kmem caches can have both accounted and unaccounted objects. > - */ > -enum kmalloc_cache_type { > - KMALLOC_NORMAL = 0, > -#ifndef CONFIG_ZONE_DMA > - KMALLOC_DMA = KMALLOC_NORMAL, > -#endif > -#ifndef CONFIG_MEMCG_KMEM > - KMALLOC_CGROUP = KMALLOC_NORMAL, > -#endif > -#ifdef CONFIG_SLUB_TINY > - KMALLOC_RECLAIM = KMALLOC_NORMAL, > -#else > - KMALLOC_RECLAIM, > -#endif > -#ifdef CONFIG_ZONE_DMA > - KMALLOC_DMA, > -#endif > -#ifdef CONFIG_MEMCG_KMEM > - KMALLOC_CGROUP, > -#endif > - NR_KMALLOC_TYPES > -}; > - > -#ifndef CONFIG_SLOB > -extern struct kmem_cache * > -kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1]; > - > -/* > - * Define gfp bits that should not be set for KMALLOC_NORMAL. > - */ > -#define KMALLOC_NOT_NORMAL_BITS \ > - (__GFP_RECLAIMABLE | \ > - (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ > - (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) > - > -static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) > -{ > - /* > - * The most common case is KMALLOC_NORMAL, so test for it > - * with a single branch for all the relevant flags. > - */ > - if (likely((flags & KMALLOC_NOT_NORMAL_BITS) == 0)) > - return KMALLOC_NORMAL; > - > - /* > - * At least one of the flags has to be set. Their priorities in > - * decreasing order are: > - * 1) __GFP_DMA > - * 2) __GFP_RECLAIMABLE > - * 3) __GFP_ACCOUNT > - */ > - if (IS_ENABLED(CONFIG_ZONE_DMA) && (flags & __GFP_DMA)) > - return KMALLOC_DMA; > - if (!IS_ENABLED(CONFIG_MEMCG_KMEM) || (flags & __GFP_RECLAIMABLE)) > - return KMALLOC_RECLAIM; > - else > - return KMALLOC_CGROUP; > -} > - > -/* > - * Figure out which kmalloc slab an allocation of a certain size > - * belongs to. > - * 0 = zero alloc > - * 1 = 65 .. 96 bytes > - * 2 = 129 .. 192 bytes > - * n = 2^(n-1)+1 .. 2^n > - * > - * Note: __kmalloc_index() is compile-time optimized, and not runtime optimized; > - * typical usage is via kmalloc_index() and therefore evaluated at compile-time. > - * Callers where !size_is_constant should only be test modules, where runtime > - * overheads of __kmalloc_index() can be tolerated. Also see kmalloc_slab(). > - */ > -static __always_inline unsigned int __kmalloc_index(size_t size, > - bool size_is_constant) > -{ > - if (!size) > - return 0; > - > - if (size <= KMALLOC_MIN_SIZE) > - return KMALLOC_SHIFT_LOW; > - > - if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96) > - return 1; > - if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192) > - return 2; > - if (size <= 8) return 3; > - if (size <= 16) return 4; > - if (size <= 32) return 5; > - if (size <= 64) return 6; > - if (size <= 128) return 7; > - if (size <= 256) return 8; > - if (size <= 512) return 9; > - if (size <= 1024) return 10; > - if (size <= 2 * 1024) return 11; > - if (size <= 4 * 1024) return 12; > - if (size <= 8 * 1024) return 13; > - if (size <= 16 * 1024) return 14; > - if (size <= 32 * 1024) return 15; > - if (size <= 64 * 1024) return 16; > - if (size <= 128 * 1024) return 17; > - if (size <= 256 * 1024) return 18; > - if (size <= 512 * 1024) return 19; > - if (size <= 1024 * 1024) return 20; > - if (size <= 2 * 1024 * 1024) return 21; > - > - if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant) > - BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()"); > - else > - BUG(); > - > - /* Will never be reached. Needed because the compiler may complain */ > - return -1; > -} > -static_assert(PAGE_SHIFT <= 20); > -#define kmalloc_index(s) __kmalloc_index(s, true) > -#endif /* !CONFIG_SLOB */ > - > void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __alloc_size(1); > > /** > @@ -567,57 +417,15 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) __assume_page_align > * Try really hard to succeed the allocation but fail > * eventually. > */ > -#ifndef CONFIG_SLOB > -static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) > -{ > - if (__builtin_constant_p(size) && size) { > - unsigned int index; > - > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large(size, flags); > - > - index = kmalloc_index(size); > - return kmalloc_trace( > - kmalloc_caches[kmalloc_type(flags)][index], > - flags, size); > - } > - return __kmalloc(size, flags); > -} > -#else > static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) > { > - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large(size, flags); > - > - return __kmalloc(size, flags); > + return kmalloc_large(size, flags); > } > -#endif > > -#ifndef CONFIG_SLOB > static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) > { > - if (__builtin_constant_p(size) && size) { > - unsigned int index; > - > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large_node(size, flags, node); > - > - index = kmalloc_index(size); > - return kmalloc_node_trace( > - kmalloc_caches[kmalloc_type(flags)][index], > - flags, node, size); > - } > - return __kmalloc_node(size, flags, node); > + return kmalloc_large_node(size, flags, node); > } > -#else > -static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) > -{ > - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large_node(size, flags, node); > - > - return __kmalloc_node(size, flags, node); > -} > -#endif > > /** > * kmalloc_array - allocate memory for an array. > @@ -785,12 +593,7 @@ size_t kmalloc_size_roundup(size_t size); > > void __init kmem_cache_init_late(void); > > -#if defined(CONFIG_SMP) && defined(CONFIG_SLAB) > -int slab_prepare_cpu(unsigned int cpu); > -int slab_dead_cpu(unsigned int cpu); > -#else > #define slab_prepare_cpu NULL > #define slab_dead_cpu NULL > -#endif > > #endif /* _LINUX_SLAB_H */ > diff --git a/include/linux/slab_def.h b/include/linux/slab_def.h > deleted file mode 100644 > index a61e7d55d0d3..000000000000 > --- a/include/linux/slab_def.h > +++ /dev/null > @@ -1,124 +0,0 @@ > -/* SPDX-License-Identifier: GPL-2.0 */ > -#ifndef _LINUX_SLAB_DEF_H > -#define _LINUX_SLAB_DEF_H > - > -#include <linux/kfence.h> > -#include <linux/reciprocal_div.h> > - > -/* > - * Definitions unique to the original Linux SLAB allocator. > - */ > - > -struct kmem_cache { > - struct array_cache __percpu *cpu_cache; > - > -/* 1) Cache tunables. Protected by slab_mutex */ > - unsigned int batchcount; > - unsigned int limit; > - unsigned int shared; > - > - unsigned int size; > - struct reciprocal_value reciprocal_buffer_size; > -/* 2) touched by every alloc & free from the backend */ > - > - slab_flags_t flags; /* constant flags */ > - unsigned int num; /* # of objs per slab */ > - > -/* 3) cache_grow/shrink */ > - /* order of pgs per slab (2^n) */ > - unsigned int gfporder; > - > - /* force GFP flags, e.g. GFP_DMA */ > - gfp_t allocflags; > - > - size_t colour; /* cache colouring range */ > - unsigned int colour_off; /* colour offset */ > - unsigned int freelist_size; > - > - /* constructor func */ > - void (*ctor)(void *obj); > - > -/* 4) cache creation/removal */ > - const char *name; > - struct list_head list; > - int refcount; > - int object_size; > - int align; > - > -/* 5) statistics */ > -#ifdef CONFIG_DEBUG_SLAB > - unsigned long num_active; > - unsigned long num_allocations; > - unsigned long high_mark; > - unsigned long grown; > - unsigned long reaped; > - unsigned long errors; > - unsigned long max_freeable; > - unsigned long node_allocs; > - unsigned long node_frees; > - unsigned long node_overflow; > - atomic_t allochit; > - atomic_t allocmiss; > - atomic_t freehit; > - atomic_t freemiss; > - > - /* > - * If debugging is enabled, then the allocator can add additional > - * fields and/or padding to every object. 'size' contains the total > - * object size including these internal fields, while 'obj_offset' > - * and 'object_size' contain the offset to the user object and its > - * size. > - */ > - int obj_offset; > -#endif /* CONFIG_DEBUG_SLAB */ > - > -#ifdef CONFIG_KASAN_GENERIC > - struct kasan_cache kasan_info; > -#endif > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > - unsigned int *random_seq; > -#endif > - > -#ifdef CONFIG_HARDENED_USERCOPY > - unsigned int useroffset; /* Usercopy region offset */ > - unsigned int usersize; /* Usercopy region size */ > -#endif > - > - struct kmem_cache_node *node[MAX_NUMNODES]; > -}; > - > -static inline void *nearest_obj(struct kmem_cache *cache, const struct slab *slab, > - void *x) > -{ > - void *object = x - (x - slab->s_mem) % cache->size; > - void *last_object = slab->s_mem + (cache->num - 1) * cache->size; > - > - if (unlikely(object > last_object)) > - return last_object; > - else > - return object; > -} > - > -/* > - * We want to avoid an expensive divide : (offset / cache->size) > - * Using the fact that size is a constant for a particular cache, > - * we can replace (offset / cache->size) by > - * reciprocal_divide(offset, cache->reciprocal_buffer_size) > - */ > -static inline unsigned int obj_to_index(const struct kmem_cache *cache, > - const struct slab *slab, void *obj) > -{ > - u32 offset = (obj - slab->s_mem); > - return reciprocal_divide(offset, cache->reciprocal_buffer_size); > -} > - > -static inline int objs_per_slab(const struct kmem_cache *cache, > - const struct slab *slab) > -{ > - if (is_kfence_address(slab_address(slab))) > - return 1; > - return cache->num; > -} > - > -#endif /* _LINUX_SLAB_DEF_H */ > diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h > deleted file mode 100644 > index f6df03f934e5..000000000000 > --- a/include/linux/slub_def.h > +++ /dev/null > @@ -1,198 +0,0 @@ > -/* SPDX-License-Identifier: GPL-2.0 */ > -#ifndef _LINUX_SLUB_DEF_H > -#define _LINUX_SLUB_DEF_H > - > -/* > - * SLUB : A Slab allocator without object queues. > - * > - * (C) 2007 SGI, Christoph Lameter > - */ > -#include <linux/kfence.h> > -#include <linux/kobject.h> > -#include <linux/reciprocal_div.h> > -#include <linux/local_lock.h> > - > -enum stat_item { > - ALLOC_FASTPATH, /* Allocation from cpu slab */ > - ALLOC_SLOWPATH, /* Allocation by getting a new cpu slab */ > - FREE_FASTPATH, /* Free to cpu slab */ > - FREE_SLOWPATH, /* Freeing not to cpu slab */ > - FREE_FROZEN, /* Freeing to frozen slab */ > - FREE_ADD_PARTIAL, /* Freeing moves slab to partial list */ > - FREE_REMOVE_PARTIAL, /* Freeing removes last object */ > - ALLOC_FROM_PARTIAL, /* Cpu slab acquired from node partial list */ > - ALLOC_SLAB, /* Cpu slab acquired from page allocator */ > - ALLOC_REFILL, /* Refill cpu slab from slab freelist */ > - ALLOC_NODE_MISMATCH, /* Switching cpu slab */ > - FREE_SLAB, /* Slab freed to the page allocator */ > - CPUSLAB_FLUSH, /* Abandoning of the cpu slab */ > - DEACTIVATE_FULL, /* Cpu slab was full when deactivated */ > - DEACTIVATE_EMPTY, /* Cpu slab was empty when deactivated */ > - DEACTIVATE_TO_HEAD, /* Cpu slab was moved to the head of partials */ > - DEACTIVATE_TO_TAIL, /* Cpu slab was moved to the tail of partials */ > - DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */ > - DEACTIVATE_BYPASS, /* Implicit deactivation */ > - ORDER_FALLBACK, /* Number of times fallback was necessary */ > - CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */ > - CMPXCHG_DOUBLE_FAIL, /* Number of times that cmpxchg double did not match */ > - CPU_PARTIAL_ALLOC, /* Used cpu partial on alloc */ > - CPU_PARTIAL_FREE, /* Refill cpu partial on free */ > - CPU_PARTIAL_NODE, /* Refill cpu partial from node partial */ > - CPU_PARTIAL_DRAIN, /* Drain cpu partial to node partial */ > - NR_SLUB_STAT_ITEMS }; > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * When changing the layout, make sure freelist and tid are still compatible > - * with this_cpu_cmpxchg_double() alignment requirements. > - */ > -struct kmem_cache_cpu { > - void **freelist; /* Pointer to next available object */ > - unsigned long tid; /* Globally unique transaction id */ > - struct slab *slab; /* The slab from which we are allocating */ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - struct slab *partial; /* Partially allocated frozen slabs */ > -#endif > - local_lock_t lock; /* Protects the fields above */ > -#ifdef CONFIG_SLUB_STATS > - unsigned stat[NR_SLUB_STAT_ITEMS]; > -#endif > -}; > -#endif /* CONFIG_SLUB_TINY */ > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -#define slub_percpu_partial(c) ((c)->partial) > - > -#define slub_set_percpu_partial(c, p) \ > -({ \ > - slub_percpu_partial(c) = (p)->next; \ > -}) > - > -#define slub_percpu_partial_read_once(c) READ_ONCE(slub_percpu_partial(c)) > -#else > -#define slub_percpu_partial(c) NULL > - > -#define slub_set_percpu_partial(c, p) > - > -#define slub_percpu_partial_read_once(c) NULL > -#endif // CONFIG_SLUB_CPU_PARTIAL > - > -/* > - * Word size structure that can be atomically updated or read and that > - * contains both the order and the number of objects that a slab of the > - * given order would contain. > - */ > -struct kmem_cache_order_objects { > - unsigned int x; > -}; > - > -/* > - * Slab cache management. > - */ > -struct kmem_cache { > -#ifndef CONFIG_SLUB_TINY > - struct kmem_cache_cpu __percpu *cpu_slab; > -#endif > - /* Used for retrieving partial slabs, etc. */ > - slab_flags_t flags; > - unsigned long min_partial; > - unsigned int size; /* The size of an object including metadata */ > - unsigned int object_size;/* The size of an object without metadata */ > - struct reciprocal_value reciprocal_size; > - unsigned int offset; /* Free pointer offset */ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - /* Number of per cpu partial objects to keep around */ > - unsigned int cpu_partial; > - /* Number of per cpu partial slabs to keep around */ > - unsigned int cpu_partial_slabs; > -#endif > - struct kmem_cache_order_objects oo; > - > - /* Allocation and freeing of slabs */ > - struct kmem_cache_order_objects min; > - gfp_t allocflags; /* gfp flags to use on each alloc */ > - int refcount; /* Refcount for slab cache destroy */ > - void (*ctor)(void *); > - unsigned int inuse; /* Offset to metadata */ > - unsigned int align; /* Alignment */ > - unsigned int red_left_pad; /* Left redzone padding size */ > - const char *name; /* Name (only for display!) */ > - struct list_head list; /* List of slab caches */ > -#ifdef CONFIG_SYSFS > - struct kobject kobj; /* For sysfs */ > -#endif > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - unsigned long random; > -#endif > - > -#ifdef CONFIG_NUMA > - /* > - * Defragmentation by allocating from a remote node. > - */ > - unsigned int remote_node_defrag_ratio; > -#endif > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > - unsigned int *random_seq; > -#endif > - > -#ifdef CONFIG_KASAN_GENERIC > - struct kasan_cache kasan_info; > -#endif > - > -#ifdef CONFIG_HARDENED_USERCOPY > - unsigned int useroffset; /* Usercopy region offset */ > - unsigned int usersize; /* Usercopy region size */ > -#endif > - > - struct kmem_cache_node *node[MAX_NUMNODES]; > -}; > - > -#if defined(CONFIG_SYSFS) && !defined(CONFIG_SLUB_TINY) > -#define SLAB_SUPPORTS_SYSFS > -void sysfs_slab_unlink(struct kmem_cache *); > -void sysfs_slab_release(struct kmem_cache *); > -#else > -static inline void sysfs_slab_unlink(struct kmem_cache *s) > -{ > -} > -static inline void sysfs_slab_release(struct kmem_cache *s) > -{ > -} > -#endif > - > -void *fixup_red_left(struct kmem_cache *s, void *p); > - > -static inline void *nearest_obj(struct kmem_cache *cache, const struct slab *slab, > - void *x) { > - void *object = x - (x - slab_address(slab)) % cache->size; > - void *last_object = slab_address(slab) + > - (slab->objects - 1) * cache->size; > - void *result = (unlikely(object > last_object)) ? last_object : object; > - > - result = fixup_red_left(cache, result); > - return result; > -} > - > -/* Determine object index from a given position */ > -static inline unsigned int __obj_to_index(const struct kmem_cache *cache, > - void *addr, void *obj) > -{ > - return reciprocal_divide(kasan_reset_tag(obj) - addr, > - cache->reciprocal_size); > -} > - > -static inline unsigned int obj_to_index(const struct kmem_cache *cache, > - const struct slab *slab, void *obj) > -{ > - if (is_kfence_address(obj)) > - return 0; > - return __obj_to_index(cache, slab_address(slab), obj); > -} > - > -static inline int objs_per_slab(const struct kmem_cache *cache, > - const struct slab *slab) > -{ > - return slab->objects; > -} > -#endif /* _LINUX_SLUB_DEF_H */ > diff --git a/init/Kconfig b/init/Kconfig > index 1fb5f313d18f..45be2eedf75c 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -973,7 +973,7 @@ config MEMCG > > config MEMCG_KMEM > bool > - depends on MEMCG && !SLOB > + depends on MEMCG && BROKEN > default y > > config BLK_CGROUP > diff --git a/mm/Kconfig b/mm/Kconfig > index 4751031f3f05..f07e81bca39e 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -210,134 +210,9 @@ config ZSMALLOC_CHAIN_SIZE > > For more information, see zsmalloc documentation. > > -menu "SLAB allocator options" > - > -choice > - prompt "Choose SLAB allocator" > - default SLUB > - help > - This option allows to select a slab allocator. > - > -config SLAB > - bool "SLAB" > - depends on !PREEMPT_RT > - select HAVE_HARDENED_USERCOPY_ALLOCATOR > - help > - The regular slab allocator that is established and known to work > - well in all environments. It organizes cache hot objects in > - per cpu and per node queues. > - > -config SLUB > - bool "SLUB (Unqueued Allocator)" > - select HAVE_HARDENED_USERCOPY_ALLOCATOR > - help > - SLUB is a slab allocator that minimizes cache line usage > - instead of managing queues of cached objects (SLAB approach). > - Per cpu caching is realized using slabs of objects instead > - of queues of objects. SLUB can use memory efficiently > - and has enhanced diagnostics. SLUB is the default choice for > - a slab allocator. > - > -config SLOB_DEPRECATED > - depends on EXPERT > - bool "SLOB (Simple Allocator - DEPRECATED)" > - depends on !PREEMPT_RT > - help > - Deprecated and scheduled for removal in a few cycles. SLUB > - recommended as replacement. CONFIG_SLUB_TINY can be considered > - on systems with 16MB or less RAM. > - > - If you need SLOB to stay, please contact linux-mm@kvack.org and > - people listed in the SLAB ALLOCATOR section of MAINTAINERS file, > - with your use case. > - > - SLOB replaces the stock allocator with a drastically simpler > - allocator. SLOB is generally more space efficient but > - does not perform as well on large systems. > - > -endchoice > - > -config SLOB > - bool > - default y > - depends on SLOB_DEPRECATED > - > -config SLUB_TINY > - bool "Configure SLUB for minimal memory footprint" > - depends on SLUB && EXPERT > - select SLAB_MERGE_DEFAULT > - help > - Configures the SLUB allocator in a way to achieve minimal memory > - footprint, sacrificing scalability, debugging and other features. > - This is intended only for the smallest system that had used the > - SLOB allocator and is not recommended for systems with more than > - 16MB RAM. > - > - If unsure, say N. > - > -config SLAB_MERGE_DEFAULT > - bool "Allow slab caches to be merged" > - default y > - depends on SLAB || SLUB > - help > - For reduced kernel memory fragmentation, slab caches can be > - merged when they share the same size and other characteristics. > - This carries a risk of kernel heap overflows being able to > - overwrite objects from merged caches (and more easily control > - cache layout), which makes such heap attacks easier to exploit > - by attackers. By keeping caches unmerged, these kinds of exploits > - can usually only damage objects in the same cache. To disable > - merging at runtime, "slab_nomerge" can be passed on the kernel > - command line. > - > -config SLAB_FREELIST_RANDOM > - bool "Randomize slab freelist" > - depends on SLAB || (SLUB && !SLUB_TINY) > - help > - Randomizes the freelist order used on creating new pages. This > - security feature reduces the predictability of the kernel slab > - allocator against heap overflows. > - > -config SLAB_FREELIST_HARDENED > - bool "Harden slab freelist metadata" > - depends on SLAB || (SLUB && !SLUB_TINY) > - help > - Many kernel heap attacks try to target slab cache metadata and > - other infrastructure. This options makes minor performance > - sacrifices to harden the kernel slab allocator against common > - freelist exploit methods. Some slab implementations have more > - sanity-checking than others. This option is most effective with > - CONFIG_SLUB. > - > -config SLUB_STATS > - default n > - bool "Enable SLUB performance statistics" > - depends on SLUB && SYSFS && !SLUB_TINY > - help > - SLUB statistics are useful to debug SLUBs allocation behavior in > - order find ways to optimize the allocator. This should never be > - enabled for production use since keeping statistics slows down > - the allocator by a few percentage points. The slabinfo command > - supports the determination of the most active slabs to figure > - out which slabs are relevant to a particular load. > - Try running: slabinfo -DA > - > -config SLUB_CPU_PARTIAL > - default y > - depends on SLUB && SMP && !SLUB_TINY > - bool "SLUB per cpu partial cache" > - help > - Per cpu partial caches accelerate objects allocation and freeing > - that is local to a processor at the price of more indeterminism > - in the latency of the free. On overflow these caches will be cleared > - which requires the taking of locks that may cause latency spikes. > - Typically one would choose no for a realtime system. > - > -endmenu # SLAB allocator options > - > config SHUFFLE_PAGE_ALLOCATOR > bool "Page allocator randomization" > - default SLAB_FREELIST_RANDOM && ACPI_NUMA > + default ACPI_NUMA > help > Randomization of the page allocator improves the average > utilization of a direct-mapped memory-side-cache. See section > @@ -345,10 +220,9 @@ config SHUFFLE_PAGE_ALLOCATOR > 6.2a specification for an example of how a platform advertises > the presence of a memory-side-cache. There are also incidental > security benefits as it reduces the predictability of page > - allocations to compliment SLAB_FREELIST_RANDOM, but the > - default granularity of shuffling on the "MAX_ORDER - 1" i.e, > - 10th order of pages is selected based on cache utilization > - benefits on x86. > + allocations, but the default granularity of shuffling on the > + "MAX_ORDER - 1" i.e, 10th order of pages is selected based on > + cache utilization benefits on x86. > > While the randomization improves cache utilization it may > negatively impact workloads on platforms without a cache. For > diff --git a/mm/Makefile b/mm/Makefile > index 8e105e5b3e29..18b0bb245fc3 100644 > --- a/mm/Makefile > +++ b/mm/Makefile > @@ -4,16 +4,12 @@ > # > > KASAN_SANITIZE_slab_common.o := n > -KASAN_SANITIZE_slab.o := n > -KASAN_SANITIZE_slub.o := n > KCSAN_SANITIZE_kmemleak.o := n > > # These produce frequent data race reports: most of them are due to races on > # the same word but accesses to different bits of that word. Re-enable KCSAN > # for these when we have more consensus on what to do about them. > KCSAN_SANITIZE_slab_common.o := n > -KCSAN_SANITIZE_slab.o := n > -KCSAN_SANITIZE_slub.o := n > KCSAN_SANITIZE_page_alloc.o := n > # But enable explicit instrumentation for memory barriers. > KCSAN_INSTRUMENT_BARRIERS := y > @@ -22,9 +18,6 @@ KCSAN_INSTRUMENT_BARRIERS := y > # flaky coverage that is not a function of syscall inputs. E.g. slab is out of > # free pages, or a task is migrated between nodes. > KCOV_INSTRUMENT_slab_common.o := n > -KCOV_INSTRUMENT_slob.o := n > -KCOV_INSTRUMENT_slab.o := n > -KCOV_INSTRUMENT_slub.o := n > KCOV_INSTRUMENT_page_alloc.o := n > KCOV_INSTRUMENT_debug-pagealloc.o := n > KCOV_INSTRUMENT_kmemleak.o := n > @@ -81,12 +74,9 @@ obj-$(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP) += hugetlb_vmemmap.o > obj-$(CONFIG_NUMA) += mempolicy.o > obj-$(CONFIG_SPARSEMEM) += sparse.o > obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o > -obj-$(CONFIG_SLOB) += slob.o > obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o > obj-$(CONFIG_KSM) += ksm.o > obj-$(CONFIG_PAGE_POISONING) += page_poison.o > -obj-$(CONFIG_SLAB) += slab.o > -obj-$(CONFIG_SLUB) += slub.o > obj-$(CONFIG_KASAN) += kasan/ > obj-$(CONFIG_KFENCE) += kfence/ > obj-$(CONFIG_KMSAN) += kmsan/ > diff --git a/mm/slab.c b/mm/slab.c > deleted file mode 100644 > index edbe722fb906..000000000000 > --- a/mm/slab.c > +++ /dev/null > @@ -1,4046 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * linux/mm/slab.c > - * Written by Mark Hemment, 1996/97. > - * (markhe@nextd.demon.co.uk) > - * > - * kmem_cache_destroy() + some cleanup - 1999 Andrea Arcangeli > - * > - * Major cleanup, different bufctl logic, per-cpu arrays > - * (c) 2000 Manfred Spraul > - * > - * Cleanup, make the head arrays unconditional, preparation for NUMA > - * (c) 2002 Manfred Spraul > - * > - * An implementation of the Slab Allocator as described in outline in; > - * UNIX Internals: The New Frontiers by Uresh Vahalia > - * Pub: Prentice Hall ISBN 0-13-101908-2 > - * or with a little more detail in; > - * The Slab Allocator: An Object-Caching Kernel Memory Allocator > - * Jeff Bonwick (Sun Microsystems). > - * Presented at: USENIX Summer 1994 Technical Conference > - * > - * The memory is organized in caches, one cache for each object type. > - * (e.g. inode_cache, dentry_cache, buffer_head, vm_area_struct) > - * Each cache consists out of many slabs (they are small (usually one > - * page long) and always contiguous), and each slab contains multiple > - * initialized objects. > - * > - * This means, that your constructor is used only for newly allocated > - * slabs and you must pass objects with the same initializations to > - * kmem_cache_free. > - * > - * Each cache can only support one memory type (GFP_DMA, GFP_HIGHMEM, > - * normal). If you need a special memory type, then must create a new > - * cache for that memory type. > - * > - * In order to reduce fragmentation, the slabs are sorted in 3 groups: > - * full slabs with 0 free objects > - * partial slabs > - * empty slabs with no allocated objects > - * > - * If partial slabs exist, then new allocations come from these slabs, > - * otherwise from empty slabs or new slabs are allocated. > - * > - * kmem_cache_destroy() CAN CRASH if you try to allocate from the cache > - * during kmem_cache_destroy(). The caller must prevent concurrent allocs. > - * > - * Each cache has a short per-cpu head array, most allocs > - * and frees go into that array, and if that array overflows, then 1/2 > - * of the entries in the array are given back into the global cache. > - * The head array is strictly LIFO and should improve the cache hit rates. > - * On SMP, it additionally reduces the spinlock operations. > - * > - * The c_cpuarray may not be read with enabled local interrupts - > - * it's changed with a smp_call_function(). > - * > - * SMP synchronization: > - * constructors and destructors are called without any locking. > - * Several members in struct kmem_cache and struct slab never change, they > - * are accessed without any locking. > - * The per-cpu arrays are never accessed from the wrong cpu, no locking, > - * and local interrupts are disabled so slab code is preempt-safe. > - * The non-constant members are protected with a per-cache irq spinlock. > - * > - * Many thanks to Mark Hemment, who wrote another per-cpu slab patch > - * in 2000 - many ideas in the current implementation are derived from > - * his patch. > - * > - * Further notes from the original documentation: > - * > - * 11 April '97. Started multi-threading - markhe > - * The global cache-chain is protected by the mutex 'slab_mutex'. > - * The sem is only needed when accessing/extending the cache-chain, which > - * can never happen inside an interrupt (kmem_cache_create(), > - * kmem_cache_shrink() and kmem_cache_reap()). > - * > - * At present, each engine can be growing a cache. This should be blocked. > - * > - * 15 March 2005. NUMA slab allocator. > - * Shai Fultheim <shai@scalex86.org>. > - * Shobhit Dayal <shobhit@calsoftinc.com> > - * Alok N Kataria <alokk@calsoftinc.com> > - * Christoph Lameter <christoph@lameter.com> > - * > - * Modified the slab allocator to be node aware on NUMA systems. > - * Each node has its own list of partial, free and full slabs. > - * All object allocations for a node occur from node specific slab lists. > - */ > - > -#include <linux/slab.h> > -#include <linux/mm.h> > -#include <linux/poison.h> > -#include <linux/swap.h> > -#include <linux/cache.h> > -#include <linux/interrupt.h> > -#include <linux/init.h> > -#include <linux/compiler.h> > -#include <linux/cpuset.h> > -#include <linux/proc_fs.h> > -#include <linux/seq_file.h> > -#include <linux/notifier.h> > -#include <linux/kallsyms.h> > -#include <linux/kfence.h> > -#include <linux/cpu.h> > -#include <linux/sysctl.h> > -#include <linux/module.h> > -#include <linux/rcupdate.h> > -#include <linux/string.h> > -#include <linux/uaccess.h> > -#include <linux/nodemask.h> > -#include <linux/kmemleak.h> > -#include <linux/mempolicy.h> > -#include <linux/mutex.h> > -#include <linux/fault-inject.h> > -#include <linux/rtmutex.h> > -#include <linux/reciprocal_div.h> > -#include <linux/debugobjects.h> > -#include <linux/memory.h> > -#include <linux/prefetch.h> > -#include <linux/sched/task_stack.h> > - > -#include <net/sock.h> > - > -#include <asm/cacheflush.h> > -#include <asm/tlbflush.h> > -#include <asm/page.h> > - > -#include <trace/events/kmem.h> > - > -#include "internal.h" > - > -#include "slab.h" > - > -/* > - * DEBUG - 1 for kmem_cache_create() to honour; SLAB_RED_ZONE & SLAB_POISON. > - * 0 for faster, smaller code (especially in the critical paths). > - * > - * STATS - 1 to collect stats for /proc/slabinfo. > - * 0 for faster, smaller code (especially in the critical paths). > - * > - * FORCED_DEBUG - 1 enables SLAB_RED_ZONE and SLAB_POISON (if possible) > - */ > - > -#ifdef CONFIG_DEBUG_SLAB > -#define DEBUG 1 > -#define STATS 1 > -#define FORCED_DEBUG 1 > -#else > -#define DEBUG 0 > -#define STATS 0 > -#define FORCED_DEBUG 0 > -#endif > - > -/* Shouldn't this be in a header file somewhere? */ > -#define BYTES_PER_WORD sizeof(void *) > -#define REDZONE_ALIGN max(BYTES_PER_WORD, __alignof__(unsigned long long)) > - > -#ifndef ARCH_KMALLOC_FLAGS > -#define ARCH_KMALLOC_FLAGS SLAB_HWCACHE_ALIGN > -#endif > - > -#define FREELIST_BYTE_INDEX (((PAGE_SIZE >> BITS_PER_BYTE) \ > - <= SLAB_OBJ_MIN_SIZE) ? 1 : 0) > - > -#if FREELIST_BYTE_INDEX > -typedef unsigned char freelist_idx_t; > -#else > -typedef unsigned short freelist_idx_t; > -#endif > - > -#define SLAB_OBJ_MAX_NUM ((1 << sizeof(freelist_idx_t) * BITS_PER_BYTE) - 1) > - > -/* > - * struct array_cache > - * > - * Purpose: > - * - LIFO ordering, to hand out cache-warm objects from _alloc > - * - reduce the number of linked list operations > - * - reduce spinlock operations > - * > - * The limit is stored in the per-cpu structure to reduce the data cache > - * footprint. > - * > - */ > -struct array_cache { > - unsigned int avail; > - unsigned int limit; > - unsigned int batchcount; > - unsigned int touched; > - void *entry[]; /* > - * Must have this definition in here for the proper > - * alignment of array_cache. Also simplifies accessing > - * the entries. > - */ > -}; > - > -struct alien_cache { > - spinlock_t lock; > - struct array_cache ac; > -}; > - > -/* > - * Need this for bootstrapping a per node allocator. > - */ > -#define NUM_INIT_LISTS (2 * MAX_NUMNODES) > -static struct kmem_cache_node __initdata init_kmem_cache_node[NUM_INIT_LISTS]; > -#define CACHE_CACHE 0 > -#define SIZE_NODE (MAX_NUMNODES) > - > -static int drain_freelist(struct kmem_cache *cache, > - struct kmem_cache_node *n, int tofree); > -static void free_block(struct kmem_cache *cachep, void **objpp, int len, > - int node, struct list_head *list); > -static void slabs_destroy(struct kmem_cache *cachep, struct list_head *list); > -static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp); > -static void cache_reap(struct work_struct *unused); > - > -static inline void fixup_objfreelist_debug(struct kmem_cache *cachep, > - void **list); > -static inline void fixup_slab_list(struct kmem_cache *cachep, > - struct kmem_cache_node *n, struct slab *slab, > - void **list); > - > -#define INDEX_NODE kmalloc_index(sizeof(struct kmem_cache_node)) > - > -static void kmem_cache_node_init(struct kmem_cache_node *parent) > -{ > - INIT_LIST_HEAD(&parent->slabs_full); > - INIT_LIST_HEAD(&parent->slabs_partial); > - INIT_LIST_HEAD(&parent->slabs_free); > - parent->total_slabs = 0; > - parent->free_slabs = 0; > - parent->shared = NULL; > - parent->alien = NULL; > - parent->colour_next = 0; > - raw_spin_lock_init(&parent->list_lock); > - parent->free_objects = 0; > - parent->free_touched = 0; > -} > - > -#define MAKE_LIST(cachep, listp, slab, nodeid) \ > - do { \ > - INIT_LIST_HEAD(listp); \ > - list_splice(&get_node(cachep, nodeid)->slab, listp); \ > - } while (0) > - > -#define MAKE_ALL_LISTS(cachep, ptr, nodeid) \ > - do { \ > - MAKE_LIST((cachep), (&(ptr)->slabs_full), slabs_full, nodeid); \ > - MAKE_LIST((cachep), (&(ptr)->slabs_partial), slabs_partial, nodeid); \ > - MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid); \ > - } while (0) > - > -#define CFLGS_OBJFREELIST_SLAB ((slab_flags_t __force)0x40000000U) > -#define CFLGS_OFF_SLAB ((slab_flags_t __force)0x80000000U) > -#define OBJFREELIST_SLAB(x) ((x)->flags & CFLGS_OBJFREELIST_SLAB) > -#define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB) > - > -#define BATCHREFILL_LIMIT 16 > -/* > - * Optimization question: fewer reaps means less probability for unnecessary > - * cpucache drain/refill cycles. > - * > - * OTOH the cpuarrays can contain lots of objects, > - * which could lock up otherwise freeable slabs. > - */ > -#define REAPTIMEOUT_AC (2*HZ) > -#define REAPTIMEOUT_NODE (4*HZ) > - > -#if STATS > -#define STATS_INC_ACTIVE(x) ((x)->num_active++) > -#define STATS_DEC_ACTIVE(x) ((x)->num_active--) > -#define STATS_INC_ALLOCED(x) ((x)->num_allocations++) > -#define STATS_INC_GROWN(x) ((x)->grown++) > -#define STATS_ADD_REAPED(x, y) ((x)->reaped += (y)) > -#define STATS_SET_HIGH(x) \ > - do { \ > - if ((x)->num_active > (x)->high_mark) \ > - (x)->high_mark = (x)->num_active; \ > - } while (0) > -#define STATS_INC_ERR(x) ((x)->errors++) > -#define STATS_INC_NODEALLOCS(x) ((x)->node_allocs++) > -#define STATS_INC_NODEFREES(x) ((x)->node_frees++) > -#define STATS_INC_ACOVERFLOW(x) ((x)->node_overflow++) > -#define STATS_SET_FREEABLE(x, i) \ > - do { \ > - if ((x)->max_freeable < i) \ > - (x)->max_freeable = i; \ > - } while (0) > -#define STATS_INC_ALLOCHIT(x) atomic_inc(&(x)->allochit) > -#define STATS_INC_ALLOCMISS(x) atomic_inc(&(x)->allocmiss) > -#define STATS_INC_FREEHIT(x) atomic_inc(&(x)->freehit) > -#define STATS_INC_FREEMISS(x) atomic_inc(&(x)->freemiss) > -#else > -#define STATS_INC_ACTIVE(x) do { } while (0) > -#define STATS_DEC_ACTIVE(x) do { } while (0) > -#define STATS_INC_ALLOCED(x) do { } while (0) > -#define STATS_INC_GROWN(x) do { } while (0) > -#define STATS_ADD_REAPED(x, y) do { (void)(y); } while (0) > -#define STATS_SET_HIGH(x) do { } while (0) > -#define STATS_INC_ERR(x) do { } while (0) > -#define STATS_INC_NODEALLOCS(x) do { } while (0) > -#define STATS_INC_NODEFREES(x) do { } while (0) > -#define STATS_INC_ACOVERFLOW(x) do { } while (0) > -#define STATS_SET_FREEABLE(x, i) do { } while (0) > -#define STATS_INC_ALLOCHIT(x) do { } while (0) > -#define STATS_INC_ALLOCMISS(x) do { } while (0) > -#define STATS_INC_FREEHIT(x) do { } while (0) > -#define STATS_INC_FREEMISS(x) do { } while (0) > -#endif > - > -#if DEBUG > - > -/* > - * memory layout of objects: > - * 0 : objp > - * 0 .. cachep->obj_offset - BYTES_PER_WORD - 1: padding. This ensures that > - * the end of an object is aligned with the end of the real > - * allocation. Catches writes behind the end of the allocation. > - * cachep->obj_offset - BYTES_PER_WORD .. cachep->obj_offset - 1: > - * redzone word. > - * cachep->obj_offset: The real object. > - * cachep->size - 2* BYTES_PER_WORD: redzone word [BYTES_PER_WORD long] > - * cachep->size - 1* BYTES_PER_WORD: last caller address > - * [BYTES_PER_WORD long] > - */ > -static int obj_offset(struct kmem_cache *cachep) > -{ > - return cachep->obj_offset; > -} > - > -static unsigned long long *dbg_redzone1(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); > - return (unsigned long long *) (objp + obj_offset(cachep) - > - sizeof(unsigned long long)); > -} > - > -static unsigned long long *dbg_redzone2(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); > - if (cachep->flags & SLAB_STORE_USER) > - return (unsigned long long *)(objp + cachep->size - > - sizeof(unsigned long long) - > - REDZONE_ALIGN); > - return (unsigned long long *) (objp + cachep->size - > - sizeof(unsigned long long)); > -} > - > -static void **dbg_userword(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_STORE_USER)); > - return (void **)(objp + cachep->size - BYTES_PER_WORD); > -} > - > -#else > - > -#define obj_offset(x) 0 > -#define dbg_redzone1(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) > -#define dbg_redzone2(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) > -#define dbg_userword(cachep, objp) ({BUG(); (void **)NULL;}) > - > -#endif > - > -/* > - * Do not go above this order unless 0 objects fit into the slab or > - * overridden on the command line. > - */ > -#define SLAB_MAX_ORDER_HI 1 > -#define SLAB_MAX_ORDER_LO 0 > -static int slab_max_order = SLAB_MAX_ORDER_LO; > -static bool slab_max_order_set __initdata; > - > -static inline void *index_to_obj(struct kmem_cache *cache, > - const struct slab *slab, unsigned int idx) > -{ > - return slab->s_mem + cache->size * idx; > -} > - > -#define BOOT_CPUCACHE_ENTRIES 1 > -/* internal cache of cache description objs */ > -static struct kmem_cache kmem_cache_boot = { > - .batchcount = 1, > - .limit = BOOT_CPUCACHE_ENTRIES, > - .shared = 1, > - .size = sizeof(struct kmem_cache), > - .name = "kmem_cache", > -}; > - > -static DEFINE_PER_CPU(struct delayed_work, slab_reap_work); > - > -static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) > -{ > - return this_cpu_ptr(cachep->cpu_cache); > -} > - > -/* > - * Calculate the number of objects and left-over bytes for a given buffer size. > - */ > -static unsigned int cache_estimate(unsigned long gfporder, size_t buffer_size, > - slab_flags_t flags, size_t *left_over) > -{ > - unsigned int num; > - size_t slab_size = PAGE_SIZE << gfporder; > - > - /* > - * The slab management structure can be either off the slab or > - * on it. For the latter case, the memory allocated for a > - * slab is used for: > - * > - * - @buffer_size bytes for each object > - * - One freelist_idx_t for each object > - * > - * We don't need to consider alignment of freelist because > - * freelist will be at the end of slab page. The objects will be > - * at the correct alignment. > - * > - * If the slab management structure is off the slab, then the > - * alignment will already be calculated into the size. Because > - * the slabs are all pages aligned, the objects will be at the > - * correct alignment when allocated. > - */ > - if (flags & (CFLGS_OBJFREELIST_SLAB | CFLGS_OFF_SLAB)) { > - num = slab_size / buffer_size; > - *left_over = slab_size % buffer_size; > - } else { > - num = slab_size / (buffer_size + sizeof(freelist_idx_t)); > - *left_over = slab_size % > - (buffer_size + sizeof(freelist_idx_t)); > - } > - > - return num; > -} > - > -#if DEBUG > -#define slab_error(cachep, msg) __slab_error(__func__, cachep, msg) > - > -static void __slab_error(const char *function, struct kmem_cache *cachep, > - char *msg) > -{ > - pr_err("slab error in %s(): cache `%s': %s\n", > - function, cachep->name, msg); > - dump_stack(); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > -#endif > - > -/* > - * By default on NUMA we use alien caches to stage the freeing of > - * objects allocated from other nodes. This causes massive memory > - * inefficiencies when using fake NUMA setup to split memory into a > - * large number of small nodes, so it can be disabled on the command > - * line > - */ > - > -static int use_alien_caches __read_mostly = 1; > -static int __init noaliencache_setup(char *s) > -{ > - use_alien_caches = 0; > - return 1; > -} > -__setup("noaliencache", noaliencache_setup); > - > -static int __init slab_max_order_setup(char *str) > -{ > - get_option(&str, &slab_max_order); > - slab_max_order = slab_max_order < 0 ? 0 : > - min(slab_max_order, MAX_ORDER - 1); > - slab_max_order_set = true; > - > - return 1; > -} > -__setup("slab_max_order=", slab_max_order_setup); > - > -#ifdef CONFIG_NUMA > -/* > - * Special reaping functions for NUMA systems called from cache_reap(). > - * These take care of doing round robin flushing of alien caches (containing > - * objects freed on different nodes from which they were allocated) and the > - * flushing of remote pcps by calling drain_node_pages. > - */ > -static DEFINE_PER_CPU(unsigned long, slab_reap_node); > - > -static void init_reap_node(int cpu) > -{ > - per_cpu(slab_reap_node, cpu) = next_node_in(cpu_to_mem(cpu), > - node_online_map); > -} > - > -static void next_reap_node(void) > -{ > - int node = __this_cpu_read(slab_reap_node); > - > - node = next_node_in(node, node_online_map); > - __this_cpu_write(slab_reap_node, node); > -} > - > -#else > -#define init_reap_node(cpu) do { } while (0) > -#define next_reap_node(void) do { } while (0) > -#endif > - > -/* > - * Initiate the reap timer running on the target CPU. We run at around 1 to 2Hz > - * via the workqueue/eventd. > - * Add the CPU number into the expiration time to minimize the possibility of > - * the CPUs getting into lockstep and contending for the global cache chain > - * lock. > - */ > -static void start_cpu_timer(int cpu) > -{ > - struct delayed_work *reap_work = &per_cpu(slab_reap_work, cpu); > - > - if (reap_work->work.func == NULL) { > - init_reap_node(cpu); > - INIT_DEFERRABLE_WORK(reap_work, cache_reap); > - schedule_delayed_work_on(cpu, reap_work, > - __round_jiffies_relative(HZ, cpu)); > - } > -} > - > -static void init_arraycache(struct array_cache *ac, int limit, int batch) > -{ > - if (ac) { > - ac->avail = 0; > - ac->limit = limit; > - ac->batchcount = batch; > - ac->touched = 0; > - } > -} > - > -static struct array_cache *alloc_arraycache(int node, int entries, > - int batchcount, gfp_t gfp) > -{ > - size_t memsize = sizeof(void *) * entries + sizeof(struct array_cache); > - struct array_cache *ac = NULL; > - > - ac = kmalloc_node(memsize, gfp, node); > - /* > - * The array_cache structures contain pointers to free object. > - * However, when such objects are allocated or transferred to another > - * cache the pointers are not cleared and they could be counted as > - * valid references during a kmemleak scan. Therefore, kmemleak must > - * not scan such objects. > - */ > - kmemleak_no_scan(ac); > - init_arraycache(ac, entries, batchcount); > - return ac; > -} > - > -static noinline void cache_free_pfmemalloc(struct kmem_cache *cachep, > - struct slab *slab, void *objp) > -{ > - struct kmem_cache_node *n; > - int slab_node; > - LIST_HEAD(list); > - > - slab_node = slab_nid(slab); > - n = get_node(cachep, slab_node); > - > - raw_spin_lock(&n->list_lock); > - free_block(cachep, &objp, 1, slab_node, &list); > - raw_spin_unlock(&n->list_lock); > - > - slabs_destroy(cachep, &list); > -} > - > -/* > - * Transfer objects in one arraycache to another. > - * Locking must be handled by the caller. > - * > - * Return the number of entries transferred. > - */ > -static int transfer_objects(struct array_cache *to, > - struct array_cache *from, unsigned int max) > -{ > - /* Figure out how many entries to transfer */ > - int nr = min3(from->avail, max, to->limit - to->avail); > - > - if (!nr) > - return 0; > - > - memcpy(to->entry + to->avail, from->entry + from->avail - nr, > - sizeof(void *) *nr); > - > - from->avail -= nr; > - to->avail += nr; > - return nr; > -} > - > -/* &alien->lock must be held by alien callers. */ > -static __always_inline void __free_one(struct array_cache *ac, void *objp) > -{ > - /* Avoid trivial double-free. */ > - if (IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && > - WARN_ON_ONCE(ac->avail > 0 && ac->entry[ac->avail - 1] == objp)) > - return; > - ac->entry[ac->avail++] = objp; > -} > - > -#ifndef CONFIG_NUMA > - > -#define drain_alien_cache(cachep, alien) do { } while (0) > -#define reap_alien(cachep, n) do { } while (0) > - > -static inline struct alien_cache **alloc_alien_cache(int node, > - int limit, gfp_t gfp) > -{ > - return NULL; > -} > - > -static inline void free_alien_cache(struct alien_cache **ac_ptr) > -{ > -} > - > -static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) > -{ > - return 0; > -} > - > -static inline gfp_t gfp_exact_node(gfp_t flags) > -{ > - return flags & ~__GFP_NOFAIL; > -} > - > -#else /* CONFIG_NUMA */ > - > -static struct alien_cache *__alloc_alien_cache(int node, int entries, > - int batch, gfp_t gfp) > -{ > - size_t memsize = sizeof(void *) * entries + sizeof(struct alien_cache); > - struct alien_cache *alc = NULL; > - > - alc = kmalloc_node(memsize, gfp, node); > - if (alc) { > - kmemleak_no_scan(alc); > - init_arraycache(&alc->ac, entries, batch); > - spin_lock_init(&alc->lock); > - } > - return alc; > -} > - > -static struct alien_cache **alloc_alien_cache(int node, int limit, gfp_t gfp) > -{ > - struct alien_cache **alc_ptr; > - int i; > - > - if (limit > 1) > - limit = 12; > - alc_ptr = kcalloc_node(nr_node_ids, sizeof(void *), gfp, node); > - if (!alc_ptr) > - return NULL; > - > - for_each_node(i) { > - if (i == node || !node_online(i)) > - continue; > - alc_ptr[i] = __alloc_alien_cache(node, limit, 0xbaadf00d, gfp); > - if (!alc_ptr[i]) { > - for (i--; i >= 0; i--) > - kfree(alc_ptr[i]); > - kfree(alc_ptr); > - return NULL; > - } > - } > - return alc_ptr; > -} > - > -static void free_alien_cache(struct alien_cache **alc_ptr) > -{ > - int i; > - > - if (!alc_ptr) > - return; > - for_each_node(i) > - kfree(alc_ptr[i]); > - kfree(alc_ptr); > -} > - > -static void __drain_alien_cache(struct kmem_cache *cachep, > - struct array_cache *ac, int node, > - struct list_head *list) > -{ > - struct kmem_cache_node *n = get_node(cachep, node); > - > - if (ac->avail) { > - raw_spin_lock(&n->list_lock); > - /* > - * Stuff objects into the remote nodes shared array first. > - * That way we could avoid the overhead of putting the objects > - * into the free lists and getting them back later. > - */ > - if (n->shared) > - transfer_objects(n->shared, ac, ac->limit); > - > - free_block(cachep, ac->entry, ac->avail, node, list); > - ac->avail = 0; > - raw_spin_unlock(&n->list_lock); > - } > -} > - > -/* > - * Called from cache_reap() to regularly drain alien caches round robin. > - */ > -static void reap_alien(struct kmem_cache *cachep, struct kmem_cache_node *n) > -{ > - int node = __this_cpu_read(slab_reap_node); > - > - if (n->alien) { > - struct alien_cache *alc = n->alien[node]; > - struct array_cache *ac; > - > - if (alc) { > - ac = &alc->ac; > - if (ac->avail && spin_trylock_irq(&alc->lock)) { > - LIST_HEAD(list); > - > - __drain_alien_cache(cachep, ac, node, &list); > - spin_unlock_irq(&alc->lock); > - slabs_destroy(cachep, &list); > - } > - } > - } > -} > - > -static void drain_alien_cache(struct kmem_cache *cachep, > - struct alien_cache **alien) > -{ > - int i = 0; > - struct alien_cache *alc; > - struct array_cache *ac; > - unsigned long flags; > - > - for_each_online_node(i) { > - alc = alien[i]; > - if (alc) { > - LIST_HEAD(list); > - > - ac = &alc->ac; > - spin_lock_irqsave(&alc->lock, flags); > - __drain_alien_cache(cachep, ac, i, &list); > - spin_unlock_irqrestore(&alc->lock, flags); > - slabs_destroy(cachep, &list); > - } > - } > -} > - > -static int __cache_free_alien(struct kmem_cache *cachep, void *objp, > - int node, int slab_node) > -{ > - struct kmem_cache_node *n; > - struct alien_cache *alien = NULL; > - struct array_cache *ac; > - LIST_HEAD(list); > - > - n = get_node(cachep, node); > - STATS_INC_NODEFREES(cachep); > - if (n->alien && n->alien[slab_node]) { > - alien = n->alien[slab_node]; > - ac = &alien->ac; > - spin_lock(&alien->lock); > - if (unlikely(ac->avail == ac->limit)) { > - STATS_INC_ACOVERFLOW(cachep); > - __drain_alien_cache(cachep, ac, slab_node, &list); > - } > - __free_one(ac, objp); > - spin_unlock(&alien->lock); > - slabs_destroy(cachep, &list); > - } else { > - n = get_node(cachep, slab_node); > - raw_spin_lock(&n->list_lock); > - free_block(cachep, &objp, 1, slab_node, &list); > - raw_spin_unlock(&n->list_lock); > - slabs_destroy(cachep, &list); > - } > - return 1; > -} > - > -static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) > -{ > - int slab_node = slab_nid(virt_to_slab(objp)); > - int node = numa_mem_id(); > - /* > - * Make sure we are not freeing an object from another node to the array > - * cache on this cpu. > - */ > - if (likely(node == slab_node)) > - return 0; > - > - return __cache_free_alien(cachep, objp, node, slab_node); > -} > - > -/* > - * Construct gfp mask to allocate from a specific node but do not reclaim or > - * warn about failures. > - */ > -static inline gfp_t gfp_exact_node(gfp_t flags) > -{ > - return (flags | __GFP_THISNODE | __GFP_NOWARN) & ~(__GFP_RECLAIM|__GFP_NOFAIL); > -} > -#endif > - > -static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp) > -{ > - struct kmem_cache_node *n; > - > - /* > - * Set up the kmem_cache_node for cpu before we can > - * begin anything. Make sure some other cpu on this > - * node has not already allocated this > - */ > - n = get_node(cachep, node); > - if (n) { > - raw_spin_lock_irq(&n->list_lock); > - n->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount + > - cachep->num; > - raw_spin_unlock_irq(&n->list_lock); > - > - return 0; > - } > - > - n = kmalloc_node(sizeof(struct kmem_cache_node), gfp, node); > - if (!n) > - return -ENOMEM; > - > - kmem_cache_node_init(n); > - n->next_reap = jiffies + REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - > - n->free_limit = > - (1 + nr_cpus_node(node)) * cachep->batchcount + cachep->num; > - > - /* > - * The kmem_cache_nodes don't come and go as CPUs > - * come and go. slab_mutex provides sufficient > - * protection here. > - */ > - cachep->node[node] = n; > - > - return 0; > -} > - > -#if defined(CONFIG_NUMA) || defined(CONFIG_SMP) > -/* > - * Allocates and initializes node for a node on each slab cache, used for > - * either memory or cpu hotplug. If memory is being hot-added, the kmem_cache_node > - * will be allocated off-node since memory is not yet online for the new node. > - * When hotplugging memory or a cpu, existing nodes are not replaced if > - * already in use. > - * > - * Must hold slab_mutex. > - */ > -static int init_cache_node_node(int node) > -{ > - int ret; > - struct kmem_cache *cachep; > - > - list_for_each_entry(cachep, &slab_caches, list) { > - ret = init_cache_node(cachep, node, GFP_KERNEL); > - if (ret) > - return ret; > - } > - > - return 0; > -} > -#endif > - > -static int setup_kmem_cache_node(struct kmem_cache *cachep, > - int node, gfp_t gfp, bool force_change) > -{ > - int ret = -ENOMEM; > - struct kmem_cache_node *n; > - struct array_cache *old_shared = NULL; > - struct array_cache *new_shared = NULL; > - struct alien_cache **new_alien = NULL; > - LIST_HEAD(list); > - > - if (use_alien_caches) { > - new_alien = alloc_alien_cache(node, cachep->limit, gfp); > - if (!new_alien) > - goto fail; > - } > - > - if (cachep->shared) { > - new_shared = alloc_arraycache(node, > - cachep->shared * cachep->batchcount, 0xbaadf00d, gfp); > - if (!new_shared) > - goto fail; > - } > - > - ret = init_cache_node(cachep, node, gfp); > - if (ret) > - goto fail; > - > - n = get_node(cachep, node); > - raw_spin_lock_irq(&n->list_lock); > - if (n->shared && force_change) { > - free_block(cachep, n->shared->entry, > - n->shared->avail, node, &list); > - n->shared->avail = 0; > - } > - > - if (!n->shared || force_change) { > - old_shared = n->shared; > - n->shared = new_shared; > - new_shared = NULL; > - } > - > - if (!n->alien) { > - n->alien = new_alien; > - new_alien = NULL; > - } > - > - raw_spin_unlock_irq(&n->list_lock); > - slabs_destroy(cachep, &list); > - > - /* > - * To protect lockless access to n->shared during irq disabled context. > - * If n->shared isn't NULL in irq disabled context, accessing to it is > - * guaranteed to be valid until irq is re-enabled, because it will be > - * freed after synchronize_rcu(). > - */ > - if (old_shared && force_change) > - synchronize_rcu(); > - > -fail: > - kfree(old_shared); > - kfree(new_shared); > - free_alien_cache(new_alien); > - > - return ret; > -} > - > -#ifdef CONFIG_SMP > - > -static void cpuup_canceled(long cpu) > -{ > - struct kmem_cache *cachep; > - struct kmem_cache_node *n = NULL; > - int node = cpu_to_mem(cpu); > - const struct cpumask *mask = cpumask_of_node(node); > - > - list_for_each_entry(cachep, &slab_caches, list) { > - struct array_cache *nc; > - struct array_cache *shared; > - struct alien_cache **alien; > - LIST_HEAD(list); > - > - n = get_node(cachep, node); > - if (!n) > - continue; > - > - raw_spin_lock_irq(&n->list_lock); > - > - /* Free limit for this kmem_cache_node */ > - n->free_limit -= cachep->batchcount; > - > - /* cpu is dead; no one can alloc from it. */ > - nc = per_cpu_ptr(cachep->cpu_cache, cpu); > - free_block(cachep, nc->entry, nc->avail, node, &list); > - nc->avail = 0; > - > - if (!cpumask_empty(mask)) { > - raw_spin_unlock_irq(&n->list_lock); > - goto free_slab; > - } > - > - shared = n->shared; > - if (shared) { > - free_block(cachep, shared->entry, > - shared->avail, node, &list); > - n->shared = NULL; > - } > - > - alien = n->alien; > - n->alien = NULL; > - > - raw_spin_unlock_irq(&n->list_lock); > - > - kfree(shared); > - if (alien) { > - drain_alien_cache(cachep, alien); > - free_alien_cache(alien); > - } > - > -free_slab: > - slabs_destroy(cachep, &list); > - } > - /* > - * In the previous loop, all the objects were freed to > - * the respective cache's slabs, now we can go ahead and > - * shrink each nodelist to its limit. > - */ > - list_for_each_entry(cachep, &slab_caches, list) { > - n = get_node(cachep, node); > - if (!n) > - continue; > - drain_freelist(cachep, n, INT_MAX); > - } > -} > - > -static int cpuup_prepare(long cpu) > -{ > - struct kmem_cache *cachep; > - int node = cpu_to_mem(cpu); > - int err; > - > - /* > - * We need to do this right in the beginning since > - * alloc_arraycache's are going to use this list. > - * kmalloc_node allows us to add the slab to the right > - * kmem_cache_node and not this cpu's kmem_cache_node > - */ > - err = init_cache_node_node(node); > - if (err < 0) > - goto bad; > - > - /* > - * Now we can go ahead with allocating the shared arrays and > - * array caches > - */ > - list_for_each_entry(cachep, &slab_caches, list) { > - err = setup_kmem_cache_node(cachep, node, GFP_KERNEL, false); > - if (err) > - goto bad; > - } > - > - return 0; > -bad: > - cpuup_canceled(cpu); > - return -ENOMEM; > -} > - > -int slab_prepare_cpu(unsigned int cpu) > -{ > - int err; > - > - mutex_lock(&slab_mutex); > - err = cpuup_prepare(cpu); > - mutex_unlock(&slab_mutex); > - return err; > -} > - > -/* > - * This is called for a failed online attempt and for a successful > - * offline. > - * > - * Even if all the cpus of a node are down, we don't free the > - * kmem_cache_node of any cache. This is to avoid a race between cpu_down, and > - * a kmalloc allocation from another cpu for memory from the node of > - * the cpu going down. The kmem_cache_node structure is usually allocated from > - * kmem_cache_create() and gets destroyed at kmem_cache_destroy(). > - */ > -int slab_dead_cpu(unsigned int cpu) > -{ > - mutex_lock(&slab_mutex); > - cpuup_canceled(cpu); > - mutex_unlock(&slab_mutex); > - return 0; > -} > -#endif > - > -static int slab_online_cpu(unsigned int cpu) > -{ > - start_cpu_timer(cpu); > - return 0; > -} > - > -static int slab_offline_cpu(unsigned int cpu) > -{ > - /* > - * Shutdown cache reaper. Note that the slab_mutex is held so > - * that if cache_reap() is invoked it cannot do anything > - * expensive but will only modify reap_work and reschedule the > - * timer. > - */ > - cancel_delayed_work_sync(&per_cpu(slab_reap_work, cpu)); > - /* Now the cache_reaper is guaranteed to be not running. */ > - per_cpu(slab_reap_work, cpu).work.func = NULL; > - return 0; > -} > - > -#if defined(CONFIG_NUMA) > -/* > - * Drains freelist for a node on each slab cache, used for memory hot-remove. > - * Returns -EBUSY if all objects cannot be drained so that the node is not > - * removed. > - * > - * Must hold slab_mutex. > - */ > -static int __meminit drain_cache_node_node(int node) > -{ > - struct kmem_cache *cachep; > - int ret = 0; > - > - list_for_each_entry(cachep, &slab_caches, list) { > - struct kmem_cache_node *n; > - > - n = get_node(cachep, node); > - if (!n) > - continue; > - > - drain_freelist(cachep, n, INT_MAX); > - > - if (!list_empty(&n->slabs_full) || > - !list_empty(&n->slabs_partial)) { > - ret = -EBUSY; > - break; > - } > - } > - return ret; > -} > - > -static int __meminit slab_memory_callback(struct notifier_block *self, > - unsigned long action, void *arg) > -{ > - struct memory_notify *mnb = arg; > - int ret = 0; > - int nid; > - > - nid = mnb->status_change_nid; > - if (nid < 0) > - goto out; > - > - switch (action) { > - case MEM_GOING_ONLINE: > - mutex_lock(&slab_mutex); > - ret = init_cache_node_node(nid); > - mutex_unlock(&slab_mutex); > - break; > - case MEM_GOING_OFFLINE: > - mutex_lock(&slab_mutex); > - ret = drain_cache_node_node(nid); > - mutex_unlock(&slab_mutex); > - break; > - case MEM_ONLINE: > - case MEM_OFFLINE: > - case MEM_CANCEL_ONLINE: > - case MEM_CANCEL_OFFLINE: > - break; > - } > -out: > - return notifier_from_errno(ret); > -} > -#endif /* CONFIG_NUMA */ > - > -/* > - * swap the static kmem_cache_node with kmalloced memory > - */ > -static void __init init_list(struct kmem_cache *cachep, struct kmem_cache_node *list, > - int nodeid) > -{ > - struct kmem_cache_node *ptr; > - > - ptr = kmalloc_node(sizeof(struct kmem_cache_node), GFP_NOWAIT, nodeid); > - BUG_ON(!ptr); > - > - memcpy(ptr, list, sizeof(struct kmem_cache_node)); > - /* > - * Do not assume that spinlocks can be initialized via memcpy: > - */ > - raw_spin_lock_init(&ptr->list_lock); > - > - MAKE_ALL_LISTS(cachep, ptr, nodeid); > - cachep->node[nodeid] = ptr; > -} > - > -/* > - * For setting up all the kmem_cache_node for cache whose buffer_size is same as > - * size of kmem_cache_node. > - */ > -static void __init set_up_node(struct kmem_cache *cachep, int index) > -{ > - int node; > - > - for_each_online_node(node) { > - cachep->node[node] = &init_kmem_cache_node[index + node]; > - cachep->node[node]->next_reap = jiffies + > - REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - } > -} > - > -/* > - * Initialisation. Called after the page allocator have been initialised and > - * before smp_init(). > - */ > -void __init kmem_cache_init(void) > -{ > - int i; > - > - kmem_cache = &kmem_cache_boot; > - > - if (!IS_ENABLED(CONFIG_NUMA) || num_possible_nodes() == 1) > - use_alien_caches = 0; > - > - for (i = 0; i < NUM_INIT_LISTS; i++) > - kmem_cache_node_init(&init_kmem_cache_node[i]); > - > - /* > - * Fragmentation resistance on low memory - only use bigger > - * page orders on machines with more than 32MB of memory if > - * not overridden on the command line. > - */ > - if (!slab_max_order_set && totalram_pages() > (32 << 20) >> PAGE_SHIFT) > - slab_max_order = SLAB_MAX_ORDER_HI; > - > - /* Bootstrap is tricky, because several objects are allocated > - * from caches that do not exist yet: > - * 1) initialize the kmem_cache cache: it contains the struct > - * kmem_cache structures of all caches, except kmem_cache itself: > - * kmem_cache is statically allocated. > - * Initially an __init data area is used for the head array and the > - * kmem_cache_node structures, it's replaced with a kmalloc allocated > - * array at the end of the bootstrap. > - * 2) Create the first kmalloc cache. > - * The struct kmem_cache for the new cache is allocated normally. > - * An __init data area is used for the head array. > - * 3) Create the remaining kmalloc caches, with minimally sized > - * head arrays. > - * 4) Replace the __init data head arrays for kmem_cache and the first > - * kmalloc cache with kmalloc allocated arrays. > - * 5) Replace the __init data for kmem_cache_node for kmem_cache and > - * the other cache's with kmalloc allocated memory. > - * 6) Resize the head arrays of the kmalloc caches to their final sizes. > - */ > - > - /* 1) create the kmem_cache */ > - > - /* > - * struct kmem_cache size depends on nr_node_ids & nr_cpu_ids > - */ > - create_boot_cache(kmem_cache, "kmem_cache", > - offsetof(struct kmem_cache, node) + > - nr_node_ids * sizeof(struct kmem_cache_node *), > - SLAB_HWCACHE_ALIGN, 0, 0); > - list_add(&kmem_cache->list, &slab_caches); > - slab_state = PARTIAL; > - > - /* > - * Initialize the caches that provide memory for the kmem_cache_node > - * structures first. Without this, further allocations will bug. > - */ > - kmalloc_caches[KMALLOC_NORMAL][INDEX_NODE] = create_kmalloc_cache( > - kmalloc_info[INDEX_NODE].name[KMALLOC_NORMAL], > - kmalloc_info[INDEX_NODE].size, > - ARCH_KMALLOC_FLAGS, 0, > - kmalloc_info[INDEX_NODE].size); > - slab_state = PARTIAL_NODE; > - setup_kmalloc_cache_index_table(); > - > - /* 5) Replace the bootstrap kmem_cache_node */ > - { > - int nid; > - > - for_each_online_node(nid) { > - init_list(kmem_cache, &init_kmem_cache_node[CACHE_CACHE + nid], nid); > - > - init_list(kmalloc_caches[KMALLOC_NORMAL][INDEX_NODE], > - &init_kmem_cache_node[SIZE_NODE + nid], nid); > - } > - } > - > - create_kmalloc_caches(ARCH_KMALLOC_FLAGS); > -} > - > -void __init kmem_cache_init_late(void) > -{ > - struct kmem_cache *cachep; > - > - /* 6) resize the head arrays to their final sizes */ > - mutex_lock(&slab_mutex); > - list_for_each_entry(cachep, &slab_caches, list) > - if (enable_cpucache(cachep, GFP_NOWAIT)) > - BUG(); > - mutex_unlock(&slab_mutex); > - > - /* Done! */ > - slab_state = FULL; > - > -#ifdef CONFIG_NUMA > - /* > - * Register a memory hotplug callback that initializes and frees > - * node. > - */ > - hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI); > -#endif > - > - /* > - * The reap timers are started later, with a module init call: That part > - * of the kernel is not yet operational. > - */ > -} > - > -static int __init cpucache_init(void) > -{ > - int ret; > - > - /* > - * Register the timers that return unneeded pages to the page allocator > - */ > - ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "SLAB online", > - slab_online_cpu, slab_offline_cpu); > - WARN_ON(ret < 0); > - > - return 0; > -} > -__initcall(cpucache_init); > - > -static noinline void > -slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid) > -{ > -#if DEBUG > - struct kmem_cache_node *n; > - unsigned long flags; > - int node; > - static DEFINE_RATELIMIT_STATE(slab_oom_rs, DEFAULT_RATELIMIT_INTERVAL, > - DEFAULT_RATELIMIT_BURST); > - > - if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slab_oom_rs)) > - return; > - > - pr_warn("SLAB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", > - nodeid, gfpflags, &gfpflags); > - pr_warn(" cache: %s, object size: %d, order: %d\n", > - cachep->name, cachep->size, cachep->gfporder); > - > - for_each_kmem_cache_node(cachep, node, n) { > - unsigned long total_slabs, free_slabs, free_objs; > - > - raw_spin_lock_irqsave(&n->list_lock, flags); > - total_slabs = n->total_slabs; > - free_slabs = n->free_slabs; > - free_objs = n->free_objects; > - raw_spin_unlock_irqrestore(&n->list_lock, flags); > - > - pr_warn(" node %d: slabs: %ld/%ld, objs: %ld/%ld\n", > - node, total_slabs - free_slabs, total_slabs, > - (total_slabs * cachep->num) - free_objs, > - total_slabs * cachep->num); > - } > -#endif > -} > - > -/* > - * Interface to system's page allocator. No need to hold the > - * kmem_cache_node ->list_lock. > - * > - * If we requested dmaable memory, we will get it. Even if we > - * did not request dmaable memory, we might get it, but that > - * would be relatively rare and ignorable. > - */ > -static struct slab *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, > - int nodeid) > -{ > - struct folio *folio; > - struct slab *slab; > - > - flags |= cachep->allocflags; > - > - folio = (struct folio *) __alloc_pages_node(nodeid, flags, cachep->gfporder); > - if (!folio) { > - slab_out_of_memory(cachep, flags, nodeid); > - return NULL; > - } > - > - slab = folio_slab(folio); > - > - account_slab(slab, cachep->gfporder, cachep, flags); > - __folio_set_slab(folio); > - /* Make the flag visible before any changes to folio->mapping */ > - smp_wmb(); > - /* Record if ALLOC_NO_WATERMARKS was set when allocating the slab */ > - if (sk_memalloc_socks() && folio_is_pfmemalloc(folio)) > - slab_set_pfmemalloc(slab); > - > - return slab; > -} > - > -/* > - * Interface to system's page release. > - */ > -static void kmem_freepages(struct kmem_cache *cachep, struct slab *slab) > -{ > - int order = cachep->gfporder; > - struct folio *folio = slab_folio(slab); > - > - BUG_ON(!folio_test_slab(folio)); > - __slab_clear_pfmemalloc(slab); > - page_mapcount_reset(&folio->page); > - folio->mapping = NULL; > - /* Make the mapping reset visible before clearing the flag */ > - smp_wmb(); > - __folio_clear_slab(folio); > - > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += 1 << order; > - unaccount_slab(slab, order, cachep); > - __free_pages(&folio->page, order); > -} > - > -static void kmem_rcu_free(struct rcu_head *head) > -{ > - struct kmem_cache *cachep; > - struct slab *slab; > - > - slab = container_of(head, struct slab, rcu_head); > - cachep = slab->slab_cache; > - > - kmem_freepages(cachep, slab); > -} > - > -#if DEBUG > -static inline bool is_debug_pagealloc_cache(struct kmem_cache *cachep) > -{ > - return debug_pagealloc_enabled_static() && OFF_SLAB(cachep) && > - ((cachep->size % PAGE_SIZE) == 0); > -} > - > -#ifdef CONFIG_DEBUG_PAGEALLOC > -static void slab_kernel_map(struct kmem_cache *cachep, void *objp, int map) > -{ > - if (!is_debug_pagealloc_cache(cachep)) > - return; > - > - __kernel_map_pages(virt_to_page(objp), cachep->size / PAGE_SIZE, map); > -} > - > -#else > -static inline void slab_kernel_map(struct kmem_cache *cachep, void *objp, > - int map) {} > - > -#endif > - > -static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val) > -{ > - int size = cachep->object_size; > - addr = &((char *)addr)[obj_offset(cachep)]; > - > - memset(addr, val, size); > - *(unsigned char *)(addr + size - 1) = POISON_END; > -} > - > -static void dump_line(char *data, int offset, int limit) > -{ > - int i; > - unsigned char error = 0; > - int bad_count = 0; > - > - pr_err("%03x: ", offset); > - for (i = 0; i < limit; i++) { > - if (data[offset + i] != POISON_FREE) { > - error = data[offset + i]; > - bad_count++; > - } > - } > - print_hex_dump(KERN_CONT, "", 0, 16, 1, > - &data[offset], limit, 1); > - > - if (bad_count == 1) { > - error ^= POISON_FREE; > - if (!(error & (error - 1))) { > - pr_err("Single bit error detected. Probably bad RAM.\n"); > -#ifdef CONFIG_X86 > - pr_err("Run memtest86+ or a similar memory test tool.\n"); > -#else > - pr_err("Run a memory test tool.\n"); > -#endif > - } > - } > -} > -#endif > - > -#if DEBUG > - > -static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines) > -{ > - int i, size; > - char *realobj; > - > - if (cachep->flags & SLAB_RED_ZONE) { > - pr_err("Redzone: 0x%llx/0x%llx\n", > - *dbg_redzone1(cachep, objp), > - *dbg_redzone2(cachep, objp)); > - } > - > - if (cachep->flags & SLAB_STORE_USER) > - pr_err("Last user: (%pSR)\n", *dbg_userword(cachep, objp)); > - realobj = (char *)objp + obj_offset(cachep); > - size = cachep->object_size; > - for (i = 0; i < size && lines; i += 16, lines--) { > - int limit; > - limit = 16; > - if (i + limit > size) > - limit = size - i; > - dump_line(realobj, i, limit); > - } > -} > - > -static void check_poison_obj(struct kmem_cache *cachep, void *objp) > -{ > - char *realobj; > - int size, i; > - int lines = 0; > - > - if (is_debug_pagealloc_cache(cachep)) > - return; > - > - realobj = (char *)objp + obj_offset(cachep); > - size = cachep->object_size; > - > - for (i = 0; i < size; i++) { > - char exp = POISON_FREE; > - if (i == size - 1) > - exp = POISON_END; > - if (realobj[i] != exp) { > - int limit; > - /* Mismatch ! */ > - /* Print header */ > - if (lines == 0) { > - pr_err("Slab corruption (%s): %s start=%px, len=%d\n", > - print_tainted(), cachep->name, > - realobj, size); > - print_objinfo(cachep, objp, 0); > - } > - /* Hexdump the affected line */ > - i = (i / 16) * 16; > - limit = 16; > - if (i + limit > size) > - limit = size - i; > - dump_line(realobj, i, limit); > - i += 16; > - lines++; > - /* Limit to 5 lines */ > - if (lines > 5) > - break; > - } > - } > - if (lines != 0) { > - /* Print some data about the neighboring objects, if they > - * exist: > - */ > - struct slab *slab = virt_to_slab(objp); > - unsigned int objnr; > - > - objnr = obj_to_index(cachep, slab, objp); > - if (objnr) { > - objp = index_to_obj(cachep, slab, objnr - 1); > - realobj = (char *)objp + obj_offset(cachep); > - pr_err("Prev obj: start=%px, len=%d\n", realobj, size); > - print_objinfo(cachep, objp, 2); > - } > - if (objnr + 1 < cachep->num) { > - objp = index_to_obj(cachep, slab, objnr + 1); > - realobj = (char *)objp + obj_offset(cachep); > - pr_err("Next obj: start=%px, len=%d\n", realobj, size); > - print_objinfo(cachep, objp, 2); > - } > - } > -} > -#endif > - > -#if DEBUG > -static void slab_destroy_debugcheck(struct kmem_cache *cachep, > - struct slab *slab) > -{ > - int i; > - > - if (OBJFREELIST_SLAB(cachep) && cachep->flags & SLAB_POISON) { > - poison_obj(cachep, slab->freelist - obj_offset(cachep), > - POISON_FREE); > - } > - > - for (i = 0; i < cachep->num; i++) { > - void *objp = index_to_obj(cachep, slab, i); > - > - if (cachep->flags & SLAB_POISON) { > - check_poison_obj(cachep, objp); > - slab_kernel_map(cachep, objp, 1); > - } > - if (cachep->flags & SLAB_RED_ZONE) { > - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "start of a freed object was overwritten"); > - if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "end of a freed object was overwritten"); > - } > - } > -} > -#else > -static void slab_destroy_debugcheck(struct kmem_cache *cachep, > - struct slab *slab) > -{ > -} > -#endif > - > -/** > - * slab_destroy - destroy and release all objects in a slab > - * @cachep: cache pointer being destroyed > - * @slab: slab being destroyed > - * > - * Destroy all the objs in a slab, and release the mem back to the system. > - * Before calling the slab must have been unlinked from the cache. The > - * kmem_cache_node ->list_lock is not held/needed. > - */ > -static void slab_destroy(struct kmem_cache *cachep, struct slab *slab) > -{ > - void *freelist; > - > - freelist = slab->freelist; > - slab_destroy_debugcheck(cachep, slab); > - if (unlikely(cachep->flags & SLAB_TYPESAFE_BY_RCU)) > - call_rcu(&slab->rcu_head, kmem_rcu_free); > - else > - kmem_freepages(cachep, slab); > - > - /* > - * From now on, we don't use freelist > - * although actual page can be freed in rcu context > - */ > - if (OFF_SLAB(cachep)) > - kfree(freelist); > -} > - > -/* > - * Update the size of the caches before calling slabs_destroy as it may > - * recursively call kfree. > - */ > -static void slabs_destroy(struct kmem_cache *cachep, struct list_head *list) > -{ > - struct slab *slab, *n; > - > - list_for_each_entry_safe(slab, n, list, slab_list) { > - list_del(&slab->slab_list); > - slab_destroy(cachep, slab); > - } > -} > - > -/** > - * calculate_slab_order - calculate size (page order) of slabs > - * @cachep: pointer to the cache that is being created > - * @size: size of objects to be created in this cache. > - * @flags: slab allocation flags > - * > - * Also calculates the number of objects per slab. > - * > - * This could be made much more intelligent. For now, try to avoid using > - * high order pages for slabs. When the gfp() functions are more friendly > - * towards high-order requests, this should be changed. > - * > - * Return: number of left-over bytes in a slab > - */ > -static size_t calculate_slab_order(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left_over = 0; > - int gfporder; > - > - for (gfporder = 0; gfporder <= KMALLOC_MAX_ORDER; gfporder++) { > - unsigned int num; > - size_t remainder; > - > - num = cache_estimate(gfporder, size, flags, &remainder); > - if (!num) > - continue; > - > - /* Can't handle number of objects more than SLAB_OBJ_MAX_NUM */ > - if (num > SLAB_OBJ_MAX_NUM) > - break; > - > - if (flags & CFLGS_OFF_SLAB) { > - struct kmem_cache *freelist_cache; > - size_t freelist_size; > - size_t freelist_cache_size; > - > - freelist_size = num * sizeof(freelist_idx_t); > - if (freelist_size > KMALLOC_MAX_CACHE_SIZE) { > - freelist_cache_size = PAGE_SIZE << get_order(freelist_size); > - } else { > - freelist_cache = kmalloc_slab(freelist_size, 0u); > - if (!freelist_cache) > - continue; > - freelist_cache_size = freelist_cache->size; > - > - /* > - * Needed to avoid possible looping condition > - * in cache_grow_begin() > - */ > - if (OFF_SLAB(freelist_cache)) > - continue; > - } > - > - /* check if off slab has enough benefit */ > - if (freelist_cache_size > cachep->size / 2) > - continue; > - } > - > - /* Found something acceptable - save it away */ > - cachep->num = num; > - cachep->gfporder = gfporder; > - left_over = remainder; > - > - /* > - * A VFS-reclaimable slab tends to have most allocations > - * as GFP_NOFS and we really don't want to have to be allocating > - * higher-order pages when we are unable to shrink dcache. > - */ > - if (flags & SLAB_RECLAIM_ACCOUNT) > - break; > - > - /* > - * Large number of objects is good, but very large slabs are > - * currently bad for the gfp()s. > - */ > - if (gfporder >= slab_max_order) > - break; > - > - /* > - * Acceptable internal fragmentation? > - */ > - if (left_over * 8 <= (PAGE_SIZE << gfporder)) > - break; > - } > - return left_over; > -} > - > -static struct array_cache __percpu *alloc_kmem_cache_cpus( > - struct kmem_cache *cachep, int entries, int batchcount) > -{ > - int cpu; > - size_t size; > - struct array_cache __percpu *cpu_cache; > - > - size = sizeof(void *) * entries + sizeof(struct array_cache); > - cpu_cache = __alloc_percpu(size, sizeof(void *)); > - > - if (!cpu_cache) > - return NULL; > - > - for_each_possible_cpu(cpu) { > - init_arraycache(per_cpu_ptr(cpu_cache, cpu), > - entries, batchcount); > - } > - > - return cpu_cache; > -} > - > -static int __ref setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp) > -{ > - if (slab_state >= FULL) > - return enable_cpucache(cachep, gfp); > - > - cachep->cpu_cache = alloc_kmem_cache_cpus(cachep, 1, 1); > - if (!cachep->cpu_cache) > - return 1; > - > - if (slab_state == DOWN) { > - /* Creation of first cache (kmem_cache). */ > - set_up_node(kmem_cache, CACHE_CACHE); > - } else if (slab_state == PARTIAL) { > - /* For kmem_cache_node */ > - set_up_node(cachep, SIZE_NODE); > - } else { > - int node; > - > - for_each_online_node(node) { > - cachep->node[node] = kmalloc_node( > - sizeof(struct kmem_cache_node), gfp, node); > - BUG_ON(!cachep->node[node]); > - kmem_cache_node_init(cachep->node[node]); > - } > - } > - > - cachep->node[numa_mem_id()]->next_reap = > - jiffies + REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - > - cpu_cache_get(cachep)->avail = 0; > - cpu_cache_get(cachep)->limit = BOOT_CPUCACHE_ENTRIES; > - cpu_cache_get(cachep)->batchcount = 1; > - cpu_cache_get(cachep)->touched = 0; > - cachep->batchcount = 1; > - cachep->limit = BOOT_CPUCACHE_ENTRIES; > - return 0; > -} > - > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name) > -{ > - return flags; > -} > - > -struct kmem_cache * > -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > - slab_flags_t flags, void (*ctor)(void *)) > -{ > - struct kmem_cache *cachep; > - > - cachep = find_mergeable(size, align, flags, name, ctor); > - if (cachep) { > - cachep->refcount++; > - > - /* > - * Adjust the object sizes so that we clear > - * the complete object on kzalloc. > - */ > - cachep->object_size = max_t(int, cachep->object_size, size); > - } > - return cachep; > -} > - > -static bool set_objfreelist_slab_cache(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left; > - > - cachep->num = 0; > - > - /* > - * If slab auto-initialization on free is enabled, store the freelist > - * off-slab, so that its contents don't end up in one of the allocated > - * objects. > - */ > - if (unlikely(slab_want_init_on_free(cachep))) > - return false; > - > - if (cachep->ctor || flags & SLAB_TYPESAFE_BY_RCU) > - return false; > - > - left = calculate_slab_order(cachep, size, > - flags | CFLGS_OBJFREELIST_SLAB); > - if (!cachep->num) > - return false; > - > - if (cachep->num * sizeof(freelist_idx_t) > cachep->object_size) > - return false; > - > - cachep->colour = left / cachep->colour_off; > - > - return true; > -} > - > -static bool set_off_slab_cache(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left; > - > - cachep->num = 0; > - > - /* > - * Always use on-slab management when SLAB_NOLEAKTRACE > - * to avoid recursive calls into kmemleak. > - */ > - if (flags & SLAB_NOLEAKTRACE) > - return false; > - > - /* > - * Size is large, assume best to place the slab management obj > - * off-slab (should allow better packing of objs). > - */ > - left = calculate_slab_order(cachep, size, flags | CFLGS_OFF_SLAB); > - if (!cachep->num) > - return false; > - > - /* > - * If the slab has been placed off-slab, and we have enough space then > - * move it on-slab. This is at the expense of any extra colouring. > - */ > - if (left >= cachep->num * sizeof(freelist_idx_t)) > - return false; > - > - cachep->colour = left / cachep->colour_off; > - > - return true; > -} > - > -static bool set_on_slab_cache(struct kmem_cache *cachep, > - size_t size, slab_flags_t flags) > -{ > - size_t left; > - > - cachep->num = 0; > - > - left = calculate_slab_order(cachep, size, flags); > - if (!cachep->num) > - return false; > - > - cachep->colour = left / cachep->colour_off; > - > - return true; > -} > - > -/** > - * __kmem_cache_create - Create a cache. > - * @cachep: cache management descriptor > - * @flags: SLAB flags > - * > - * Returns a ptr to the cache on success, NULL on failure. > - * Cannot be called within an int, but can be interrupted. > - * The @ctor is run when new pages are allocated by the cache. > - * > - * The flags are > - * > - * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5) > - * to catch references to uninitialised memory. > - * > - * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check > - * for buffer overruns. > - * > - * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware > - * cacheline. This can be beneficial if you're counting cycles as closely > - * as davem. > - * > - * Return: a pointer to the created cache or %NULL in case of error > - */ > -int __kmem_cache_create(struct kmem_cache *cachep, slab_flags_t flags) > -{ > - size_t ralign = BYTES_PER_WORD; > - gfp_t gfp; > - int err; > - unsigned int size = cachep->size; > - > -#if DEBUG > -#if FORCED_DEBUG > - /* > - * Enable redzoning and last user accounting, except for caches with > - * large objects, if the increased size would increase the object size > - * above the next power of two: caches with object sizes just above a > - * power of two have a significant amount of internal fragmentation. > - */ > - if (size < 4096 || fls(size - 1) == fls(size-1 + REDZONE_ALIGN + > - 2 * sizeof(unsigned long long))) > - flags |= SLAB_RED_ZONE | SLAB_STORE_USER; > - if (!(flags & SLAB_TYPESAFE_BY_RCU)) > - flags |= SLAB_POISON; > -#endif > -#endif > - > - /* > - * Check that size is in terms of words. This is needed to avoid > - * unaligned accesses for some archs when redzoning is used, and makes > - * sure any on-slab bufctl's are also correctly aligned. > - */ > - size = ALIGN(size, BYTES_PER_WORD); > - > - if (flags & SLAB_RED_ZONE) { > - ralign = REDZONE_ALIGN; > - /* If redzoning, ensure that the second redzone is suitably > - * aligned, by adjusting the object size accordingly. */ > - size = ALIGN(size, REDZONE_ALIGN); > - } > - > - /* 3) caller mandated alignment */ > - if (ralign < cachep->align) { > - ralign = cachep->align; > - } > - /* disable debug if necessary */ > - if (ralign > __alignof__(unsigned long long)) > - flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); > - /* > - * 4) Store it. > - */ > - cachep->align = ralign; > - cachep->colour_off = cache_line_size(); > - /* Offset must be a multiple of the alignment. */ > - if (cachep->colour_off < cachep->align) > - cachep->colour_off = cachep->align; > - > - if (slab_is_available()) > - gfp = GFP_KERNEL; > - else > - gfp = GFP_NOWAIT; > - > -#if DEBUG > - > - /* > - * Both debugging options require word-alignment which is calculated > - * into align above. > - */ > - if (flags & SLAB_RED_ZONE) { > - /* add space for red zone words */ > - cachep->obj_offset += sizeof(unsigned long long); > - size += 2 * sizeof(unsigned long long); > - } > - if (flags & SLAB_STORE_USER) { > - /* user store requires one word storage behind the end of > - * the real object. But if the second red zone needs to be > - * aligned to 64 bits, we must allow that much space. > - */ > - if (flags & SLAB_RED_ZONE) > - size += REDZONE_ALIGN; > - else > - size += BYTES_PER_WORD; > - } > -#endif > - > - kasan_cache_create(cachep, &size, &flags); > - > - size = ALIGN(size, cachep->align); > - /* > - * We should restrict the number of objects in a slab to implement > - * byte sized index. Refer comment on SLAB_OBJ_MIN_SIZE definition. > - */ > - if (FREELIST_BYTE_INDEX && size < SLAB_OBJ_MIN_SIZE) > - size = ALIGN(SLAB_OBJ_MIN_SIZE, cachep->align); > - > -#if DEBUG > - /* > - * To activate debug pagealloc, off-slab management is necessary > - * requirement. In early phase of initialization, small sized slab > - * doesn't get initialized so it would not be possible. So, we need > - * to check size >= 256. It guarantees that all necessary small > - * sized slab is initialized in current slab initialization sequence. > - */ > - if (debug_pagealloc_enabled_static() && (flags & SLAB_POISON) && > - size >= 256 && cachep->object_size > cache_line_size()) { > - if (size < PAGE_SIZE || size % PAGE_SIZE == 0) { > - size_t tmp_size = ALIGN(size, PAGE_SIZE); > - > - if (set_off_slab_cache(cachep, tmp_size, flags)) { > - flags |= CFLGS_OFF_SLAB; > - cachep->obj_offset += tmp_size - size; > - size = tmp_size; > - goto done; > - } > - } > - } > -#endif > - > - if (set_objfreelist_slab_cache(cachep, size, flags)) { > - flags |= CFLGS_OBJFREELIST_SLAB; > - goto done; > - } > - > - if (set_off_slab_cache(cachep, size, flags)) { > - flags |= CFLGS_OFF_SLAB; > - goto done; > - } > - > - if (set_on_slab_cache(cachep, size, flags)) > - goto done; > - > - return -E2BIG; > - > -done: > - cachep->freelist_size = cachep->num * sizeof(freelist_idx_t); > - cachep->flags = flags; > - cachep->allocflags = __GFP_COMP; > - if (flags & SLAB_CACHE_DMA) > - cachep->allocflags |= GFP_DMA; > - if (flags & SLAB_CACHE_DMA32) > - cachep->allocflags |= GFP_DMA32; > - if (flags & SLAB_RECLAIM_ACCOUNT) > - cachep->allocflags |= __GFP_RECLAIMABLE; > - cachep->size = size; > - cachep->reciprocal_buffer_size = reciprocal_value(size); > - > -#if DEBUG > - /* > - * If we're going to use the generic kernel_map_pages() > - * poisoning, then it's going to smash the contents of > - * the redzone and userword anyhow, so switch them off. > - */ > - if (IS_ENABLED(CONFIG_PAGE_POISONING) && > - (cachep->flags & SLAB_POISON) && > - is_debug_pagealloc_cache(cachep)) > - cachep->flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); > -#endif > - > - err = setup_cpu_cache(cachep, gfp); > - if (err) { > - __kmem_cache_release(cachep); > - return err; > - } > - > - return 0; > -} > - > -#if DEBUG > -static void check_irq_off(void) > -{ > - BUG_ON(!irqs_disabled()); > -} > - > -static void check_irq_on(void) > -{ > - BUG_ON(irqs_disabled()); > -} > - > -static void check_mutex_acquired(void) > -{ > - BUG_ON(!mutex_is_locked(&slab_mutex)); > -} > - > -static void check_spinlock_acquired(struct kmem_cache *cachep) > -{ > -#ifdef CONFIG_SMP > - check_irq_off(); > - assert_raw_spin_locked(&get_node(cachep, numa_mem_id())->list_lock); > -#endif > -} > - > -static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node) > -{ > -#ifdef CONFIG_SMP > - check_irq_off(); > - assert_raw_spin_locked(&get_node(cachep, node)->list_lock); > -#endif > -} > - > -#else > -#define check_irq_off() do { } while(0) > -#define check_irq_on() do { } while(0) > -#define check_mutex_acquired() do { } while(0) > -#define check_spinlock_acquired(x) do { } while(0) > -#define check_spinlock_acquired_node(x, y) do { } while(0) > -#endif > - > -static void drain_array_locked(struct kmem_cache *cachep, struct array_cache *ac, > - int node, bool free_all, struct list_head *list) > -{ > - int tofree; > - > - if (!ac || !ac->avail) > - return; > - > - tofree = free_all ? ac->avail : (ac->limit + 4) / 5; > - if (tofree > ac->avail) > - tofree = (ac->avail + 1) / 2; > - > - free_block(cachep, ac->entry, tofree, node, list); > - ac->avail -= tofree; > - memmove(ac->entry, &(ac->entry[tofree]), sizeof(void *) * ac->avail); > -} > - > -static void do_drain(void *arg) > -{ > - struct kmem_cache *cachep = arg; > - struct array_cache *ac; > - int node = numa_mem_id(); > - struct kmem_cache_node *n; > - LIST_HEAD(list); > - > - check_irq_off(); > - ac = cpu_cache_get(cachep); > - n = get_node(cachep, node); > - raw_spin_lock(&n->list_lock); > - free_block(cachep, ac->entry, ac->avail, node, &list); > - raw_spin_unlock(&n->list_lock); > - ac->avail = 0; > - slabs_destroy(cachep, &list); > -} > - > -static void drain_cpu_caches(struct kmem_cache *cachep) > -{ > - struct kmem_cache_node *n; > - int node; > - LIST_HEAD(list); > - > - on_each_cpu(do_drain, cachep, 1); > - check_irq_on(); > - for_each_kmem_cache_node(cachep, node, n) > - if (n->alien) > - drain_alien_cache(cachep, n->alien); > - > - for_each_kmem_cache_node(cachep, node, n) { > - raw_spin_lock_irq(&n->list_lock); > - drain_array_locked(cachep, n->shared, node, true, &list); > - raw_spin_unlock_irq(&n->list_lock); > - > - slabs_destroy(cachep, &list); > - } > -} > - > -/* > - * Remove slabs from the list of free slabs. > - * Specify the number of slabs to drain in tofree. > - * > - * Returns the actual number of slabs released. > - */ > -static int drain_freelist(struct kmem_cache *cache, > - struct kmem_cache_node *n, int tofree) > -{ > - struct list_head *p; > - int nr_freed; > - struct slab *slab; > - > - nr_freed = 0; > - while (nr_freed < tofree && !list_empty(&n->slabs_free)) { > - > - raw_spin_lock_irq(&n->list_lock); > - p = n->slabs_free.prev; > - if (p == &n->slabs_free) { > - raw_spin_unlock_irq(&n->list_lock); > - goto out; > - } > - > - slab = list_entry(p, struct slab, slab_list); > - list_del(&slab->slab_list); > - n->free_slabs--; > - n->total_slabs--; > - /* > - * Safe to drop the lock. The slab is no longer linked > - * to the cache. > - */ > - n->free_objects -= cache->num; > - raw_spin_unlock_irq(&n->list_lock); > - slab_destroy(cache, slab); > - nr_freed++; > - > - cond_resched(); > - } > -out: > - return nr_freed; > -} > - > -bool __kmem_cache_empty(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) > - if (!list_empty(&n->slabs_full) || > - !list_empty(&n->slabs_partial)) > - return false; > - return true; > -} > - > -int __kmem_cache_shrink(struct kmem_cache *cachep) > -{ > - int ret = 0; > - int node; > - struct kmem_cache_node *n; > - > - drain_cpu_caches(cachep); > - > - check_irq_on(); > - for_each_kmem_cache_node(cachep, node, n) { > - drain_freelist(cachep, n, INT_MAX); > - > - ret += !list_empty(&n->slabs_full) || > - !list_empty(&n->slabs_partial); > - } > - return (ret ? 1 : 0); > -} > - > -int __kmem_cache_shutdown(struct kmem_cache *cachep) > -{ > - return __kmem_cache_shrink(cachep); > -} > - > -void __kmem_cache_release(struct kmem_cache *cachep) > -{ > - int i; > - struct kmem_cache_node *n; > - > - cache_random_seq_destroy(cachep); > - > - free_percpu(cachep->cpu_cache); > - > - /* NUMA: free the node structures */ > - for_each_kmem_cache_node(cachep, i, n) { > - kfree(n->shared); > - free_alien_cache(n->alien); > - kfree(n); > - cachep->node[i] = NULL; > - } > -} > - > -/* > - * Get the memory for a slab management obj. > - * > - * For a slab cache when the slab descriptor is off-slab, the > - * slab descriptor can't come from the same cache which is being created, > - * Because if it is the case, that means we defer the creation of > - * the kmalloc_{dma,}_cache of size sizeof(slab descriptor) to this point. > - * And we eventually call down to __kmem_cache_create(), which > - * in turn looks up in the kmalloc_{dma,}_caches for the desired-size one. > - * This is a "chicken-and-egg" problem. > - * > - * So the off-slab slab descriptor shall come from the kmalloc_{dma,}_caches, > - * which are all initialized during kmem_cache_init(). > - */ > -static void *alloc_slabmgmt(struct kmem_cache *cachep, > - struct slab *slab, int colour_off, > - gfp_t local_flags, int nodeid) > -{ > - void *freelist; > - void *addr = slab_address(slab); > - > - slab->s_mem = addr + colour_off; > - slab->active = 0; > - > - if (OBJFREELIST_SLAB(cachep)) > - freelist = NULL; > - else if (OFF_SLAB(cachep)) { > - /* Slab management obj is off-slab. */ > - freelist = kmalloc_node(cachep->freelist_size, > - local_flags, nodeid); > - } else { > - /* We will use last bytes at the slab for freelist */ > - freelist = addr + (PAGE_SIZE << cachep->gfporder) - > - cachep->freelist_size; > - } > - > - return freelist; > -} > - > -static inline freelist_idx_t get_free_obj(struct slab *slab, unsigned int idx) > -{ > - return ((freelist_idx_t *) slab->freelist)[idx]; > -} > - > -static inline void set_free_obj(struct slab *slab, > - unsigned int idx, freelist_idx_t val) > -{ > - ((freelist_idx_t *)(slab->freelist))[idx] = val; > -} > - > -static void cache_init_objs_debug(struct kmem_cache *cachep, struct slab *slab) > -{ > -#if DEBUG > - int i; > - > - for (i = 0; i < cachep->num; i++) { > - void *objp = index_to_obj(cachep, slab, i); > - > - if (cachep->flags & SLAB_STORE_USER) > - *dbg_userword(cachep, objp) = NULL; > - > - if (cachep->flags & SLAB_RED_ZONE) { > - *dbg_redzone1(cachep, objp) = RED_INACTIVE; > - *dbg_redzone2(cachep, objp) = RED_INACTIVE; > - } > - /* > - * Constructors are not allowed to allocate memory from the same > - * cache which they are a constructor for. Otherwise, deadlock. > - * They must also be threaded. > - */ > - if (cachep->ctor && !(cachep->flags & SLAB_POISON)) { > - kasan_unpoison_object_data(cachep, > - objp + obj_offset(cachep)); > - cachep->ctor(objp + obj_offset(cachep)); > - kasan_poison_object_data( > - cachep, objp + obj_offset(cachep)); > - } > - > - if (cachep->flags & SLAB_RED_ZONE) { > - if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "constructor overwrote the end of an object"); > - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) > - slab_error(cachep, "constructor overwrote the start of an object"); > - } > - /* need to poison the objs? */ > - if (cachep->flags & SLAB_POISON) { > - poison_obj(cachep, objp, POISON_FREE); > - slab_kernel_map(cachep, objp, 0); > - } > - } > -#endif > -} > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -/* Hold information during a freelist initialization */ > -union freelist_init_state { > - struct { > - unsigned int pos; > - unsigned int *list; > - unsigned int count; > - }; > - struct rnd_state rnd_state; > -}; > - > -/* > - * Initialize the state based on the randomization method available. > - * return true if the pre-computed list is available, false otherwise. > - */ > -static bool freelist_state_initialize(union freelist_init_state *state, > - struct kmem_cache *cachep, > - unsigned int count) > -{ > - bool ret; > - unsigned int rand; > - > - /* Use best entropy available to define a random shift */ > - rand = get_random_u32(); > - > - /* Use a random state if the pre-computed list is not available */ > - if (!cachep->random_seq) { > - prandom_seed_state(&state->rnd_state, rand); > - ret = false; > - } else { > - state->list = cachep->random_seq; > - state->count = count; > - state->pos = rand % count; > - ret = true; > - } > - return ret; > -} > - > -/* Get the next entry on the list and randomize it using a random shift */ > -static freelist_idx_t next_random_slot(union freelist_init_state *state) > -{ > - if (state->pos >= state->count) > - state->pos = 0; > - return state->list[state->pos++]; > -} > - > -/* Swap two freelist entries */ > -static void swap_free_obj(struct slab *slab, unsigned int a, unsigned int b) > -{ > - swap(((freelist_idx_t *) slab->freelist)[a], > - ((freelist_idx_t *) slab->freelist)[b]); > -} > - > -/* > - * Shuffle the freelist initialization state based on pre-computed lists. > - * return true if the list was successfully shuffled, false otherwise. > - */ > -static bool shuffle_freelist(struct kmem_cache *cachep, struct slab *slab) > -{ > - unsigned int objfreelist = 0, i, rand, count = cachep->num; > - union freelist_init_state state; > - bool precomputed; > - > - if (count < 2) > - return false; > - > - precomputed = freelist_state_initialize(&state, cachep, count); > - > - /* Take a random entry as the objfreelist */ > - if (OBJFREELIST_SLAB(cachep)) { > - if (!precomputed) > - objfreelist = count - 1; > - else > - objfreelist = next_random_slot(&state); > - slab->freelist = index_to_obj(cachep, slab, objfreelist) + > - obj_offset(cachep); > - count--; > - } > - > - /* > - * On early boot, generate the list dynamically. > - * Later use a pre-computed list for speed. > - */ > - if (!precomputed) { > - for (i = 0; i < count; i++) > - set_free_obj(slab, i, i); > - > - /* Fisher-Yates shuffle */ > - for (i = count - 1; i > 0; i--) { > - rand = prandom_u32_state(&state.rnd_state); > - rand %= (i + 1); > - swap_free_obj(slab, i, rand); > - } > - } else { > - for (i = 0; i < count; i++) > - set_free_obj(slab, i, next_random_slot(&state)); > - } > - > - if (OBJFREELIST_SLAB(cachep)) > - set_free_obj(slab, cachep->num - 1, objfreelist); > - > - return true; > -} > -#else > -static inline bool shuffle_freelist(struct kmem_cache *cachep, > - struct slab *slab) > -{ > - return false; > -} > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > - > -static void cache_init_objs(struct kmem_cache *cachep, > - struct slab *slab) > -{ > - int i; > - void *objp; > - bool shuffled; > - > - cache_init_objs_debug(cachep, slab); > - > - /* Try to randomize the freelist if enabled */ > - shuffled = shuffle_freelist(cachep, slab); > - > - if (!shuffled && OBJFREELIST_SLAB(cachep)) { > - slab->freelist = index_to_obj(cachep, slab, cachep->num - 1) + > - obj_offset(cachep); > - } > - > - for (i = 0; i < cachep->num; i++) { > - objp = index_to_obj(cachep, slab, i); > - objp = kasan_init_slab_obj(cachep, objp); > - > - /* constructor could break poison info */ > - if (DEBUG == 0 && cachep->ctor) { > - kasan_unpoison_object_data(cachep, objp); > - cachep->ctor(objp); > - kasan_poison_object_data(cachep, objp); > - } > - > - if (!shuffled) > - set_free_obj(slab, i, i); > - } > -} > - > -static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slab) > -{ > - void *objp; > - > - objp = index_to_obj(cachep, slab, get_free_obj(slab, slab->active)); > - slab->active++; > - > - return objp; > -} > - > -static void slab_put_obj(struct kmem_cache *cachep, > - struct slab *slab, void *objp) > -{ > - unsigned int objnr = obj_to_index(cachep, slab, objp); > -#if DEBUG > - unsigned int i; > - > - /* Verify double free bug */ > - for (i = slab->active; i < cachep->num; i++) { > - if (get_free_obj(slab, i) == objnr) { > - pr_err("slab: double free detected in cache '%s', objp %px\n", > - cachep->name, objp); > - BUG(); > - } > - } > -#endif > - slab->active--; > - if (!slab->freelist) > - slab->freelist = objp + obj_offset(cachep); > - > - set_free_obj(slab, slab->active, objnr); > -} > - > -/* > - * Grow (by 1) the number of slabs within a cache. This is called by > - * kmem_cache_alloc() when there are no active objs left in a cache. > - */ > -static struct slab *cache_grow_begin(struct kmem_cache *cachep, > - gfp_t flags, int nodeid) > -{ > - void *freelist; > - size_t offset; > - gfp_t local_flags; > - int slab_node; > - struct kmem_cache_node *n; > - struct slab *slab; > - > - /* > - * Be lazy and only check for valid flags here, keeping it out of the > - * critical path in kmem_cache_alloc(). > - */ > - if (unlikely(flags & GFP_SLAB_BUG_MASK)) > - flags = kmalloc_fix_flags(flags); > - > - WARN_ON_ONCE(cachep->ctor && (flags & __GFP_ZERO)); > - local_flags = flags & (GFP_CONSTRAINT_MASK|GFP_RECLAIM_MASK); > - > - check_irq_off(); > - if (gfpflags_allow_blocking(local_flags)) > - local_irq_enable(); > - > - /* > - * Get mem for the objs. Attempt to allocate a physical page from > - * 'nodeid'. > - */ > - slab = kmem_getpages(cachep, local_flags, nodeid); > - if (!slab) > - goto failed; > - > - slab_node = slab_nid(slab); > - n = get_node(cachep, slab_node); > - > - /* Get colour for the slab, and cal the next value. */ > - n->colour_next++; > - if (n->colour_next >= cachep->colour) > - n->colour_next = 0; > - > - offset = n->colour_next; > - if (offset >= cachep->colour) > - offset = 0; > - > - offset *= cachep->colour_off; > - > - /* > - * Call kasan_poison_slab() before calling alloc_slabmgmt(), so > - * page_address() in the latter returns a non-tagged pointer, > - * as it should be for slab pages. > - */ > - kasan_poison_slab(slab); > - > - /* Get slab management. */ > - freelist = alloc_slabmgmt(cachep, slab, offset, > - local_flags & ~GFP_CONSTRAINT_MASK, slab_node); > - if (OFF_SLAB(cachep) && !freelist) > - goto opps1; > - > - slab->slab_cache = cachep; > - slab->freelist = freelist; > - > - cache_init_objs(cachep, slab); > - > - if (gfpflags_allow_blocking(local_flags)) > - local_irq_disable(); > - > - return slab; > - > -opps1: > - kmem_freepages(cachep, slab); > -failed: > - if (gfpflags_allow_blocking(local_flags)) > - local_irq_disable(); > - return NULL; > -} > - > -static void cache_grow_end(struct kmem_cache *cachep, struct slab *slab) > -{ > - struct kmem_cache_node *n; > - void *list = NULL; > - > - check_irq_off(); > - > - if (!slab) > - return; > - > - INIT_LIST_HEAD(&slab->slab_list); > - n = get_node(cachep, slab_nid(slab)); > - > - raw_spin_lock(&n->list_lock); > - n->total_slabs++; > - if (!slab->active) { > - list_add_tail(&slab->slab_list, &n->slabs_free); > - n->free_slabs++; > - } else > - fixup_slab_list(cachep, n, slab, &list); > - > - STATS_INC_GROWN(cachep); > - n->free_objects += cachep->num - slab->active; > - raw_spin_unlock(&n->list_lock); > - > - fixup_objfreelist_debug(cachep, &list); > -} > - > -#if DEBUG > - > -/* > - * Perform extra freeing checks: > - * - detect bad pointers. > - * - POISON/RED_ZONE checking > - */ > -static void kfree_debugcheck(const void *objp) > -{ > - if (!virt_addr_valid(objp)) { > - pr_err("kfree_debugcheck: out of range ptr %lxh\n", > - (unsigned long)objp); > - BUG(); > - } > -} > - > -static inline void verify_redzone_free(struct kmem_cache *cache, void *obj) > -{ > - unsigned long long redzone1, redzone2; > - > - redzone1 = *dbg_redzone1(cache, obj); > - redzone2 = *dbg_redzone2(cache, obj); > - > - /* > - * Redzone is ok. > - */ > - if (redzone1 == RED_ACTIVE && redzone2 == RED_ACTIVE) > - return; > - > - if (redzone1 == RED_INACTIVE && redzone2 == RED_INACTIVE) > - slab_error(cache, "double free detected"); > - else > - slab_error(cache, "memory outside object was overwritten"); > - > - pr_err("%px: redzone 1:0x%llx, redzone 2:0x%llx\n", > - obj, redzone1, redzone2); > -} > - > -static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - unsigned int objnr; > - struct slab *slab; > - > - BUG_ON(virt_to_cache(objp) != cachep); > - > - objp -= obj_offset(cachep); > - kfree_debugcheck(objp); > - slab = virt_to_slab(objp); > - > - if (cachep->flags & SLAB_RED_ZONE) { > - verify_redzone_free(cachep, objp); > - *dbg_redzone1(cachep, objp) = RED_INACTIVE; > - *dbg_redzone2(cachep, objp) = RED_INACTIVE; > - } > - if (cachep->flags & SLAB_STORE_USER) > - *dbg_userword(cachep, objp) = (void *)caller; > - > - objnr = obj_to_index(cachep, slab, objp); > - > - BUG_ON(objnr >= cachep->num); > - BUG_ON(objp != index_to_obj(cachep, slab, objnr)); > - > - if (cachep->flags & SLAB_POISON) { > - poison_obj(cachep, objp, POISON_FREE); > - slab_kernel_map(cachep, objp, 0); > - } > - return objp; > -} > - > -#else > -#define kfree_debugcheck(x) do { } while(0) > -#define cache_free_debugcheck(x, objp, z) (objp) > -#endif > - > -static inline void fixup_objfreelist_debug(struct kmem_cache *cachep, > - void **list) > -{ > -#if DEBUG > - void *next = *list; > - void *objp; > - > - while (next) { > - objp = next - obj_offset(cachep); > - next = *(void **)next; > - poison_obj(cachep, objp, POISON_FREE); > - } > -#endif > -} > - > -static inline void fixup_slab_list(struct kmem_cache *cachep, > - struct kmem_cache_node *n, struct slab *slab, > - void **list) > -{ > - /* move slabp to correct slabp list: */ > - list_del(&slab->slab_list); > - if (slab->active == cachep->num) { > - list_add(&slab->slab_list, &n->slabs_full); > - if (OBJFREELIST_SLAB(cachep)) { > -#if DEBUG > - /* Poisoning will be done without holding the lock */ > - if (cachep->flags & SLAB_POISON) { > - void **objp = slab->freelist; > - > - *objp = *list; > - *list = objp; > - } > -#endif > - slab->freelist = NULL; > - } > - } else > - list_add(&slab->slab_list, &n->slabs_partial); > -} > - > -/* Try to find non-pfmemalloc slab if needed */ > -static noinline struct slab *get_valid_first_slab(struct kmem_cache_node *n, > - struct slab *slab, bool pfmemalloc) > -{ > - if (!slab) > - return NULL; > - > - if (pfmemalloc) > - return slab; > - > - if (!slab_test_pfmemalloc(slab)) > - return slab; > - > - /* No need to keep pfmemalloc slab if we have enough free objects */ > - if (n->free_objects > n->free_limit) { > - slab_clear_pfmemalloc(slab); > - return slab; > - } > - > - /* Move pfmemalloc slab to the end of list to speed up next search */ > - list_del(&slab->slab_list); > - if (!slab->active) { > - list_add_tail(&slab->slab_list, &n->slabs_free); > - n->free_slabs++; > - } else > - list_add_tail(&slab->slab_list, &n->slabs_partial); > - > - list_for_each_entry(slab, &n->slabs_partial, slab_list) { > - if (!slab_test_pfmemalloc(slab)) > - return slab; > - } > - > - n->free_touched = 1; > - list_for_each_entry(slab, &n->slabs_free, slab_list) { > - if (!slab_test_pfmemalloc(slab)) { > - n->free_slabs--; > - return slab; > - } > - } > - > - return NULL; > -} > - > -static struct slab *get_first_slab(struct kmem_cache_node *n, bool pfmemalloc) > -{ > - struct slab *slab; > - > - assert_raw_spin_locked(&n->list_lock); > - slab = list_first_entry_or_null(&n->slabs_partial, struct slab, > - slab_list); > - if (!slab) { > - n->free_touched = 1; > - slab = list_first_entry_or_null(&n->slabs_free, struct slab, > - slab_list); > - if (slab) > - n->free_slabs--; > - } > - > - if (sk_memalloc_socks()) > - slab = get_valid_first_slab(n, slab, pfmemalloc); > - > - return slab; > -} > - > -static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep, > - struct kmem_cache_node *n, gfp_t flags) > -{ > - struct slab *slab; > - void *obj; > - void *list = NULL; > - > - if (!gfp_pfmemalloc_allowed(flags)) > - return NULL; > - > - raw_spin_lock(&n->list_lock); > - slab = get_first_slab(n, true); > - if (!slab) { > - raw_spin_unlock(&n->list_lock); > - return NULL; > - } > - > - obj = slab_get_obj(cachep, slab); > - n->free_objects--; > - > - fixup_slab_list(cachep, n, slab, &list); > - > - raw_spin_unlock(&n->list_lock); > - fixup_objfreelist_debug(cachep, &list); > - > - return obj; > -} > - > -/* > - * Slab list should be fixed up by fixup_slab_list() for existing slab > - * or cache_grow_end() for new slab > - */ > -static __always_inline int alloc_block(struct kmem_cache *cachep, > - struct array_cache *ac, struct slab *slab, int batchcount) > -{ > - /* > - * There must be at least one object available for > - * allocation. > - */ > - BUG_ON(slab->active >= cachep->num); > - > - while (slab->active < cachep->num && batchcount--) { > - STATS_INC_ALLOCED(cachep); > - STATS_INC_ACTIVE(cachep); > - STATS_SET_HIGH(cachep); > - > - ac->entry[ac->avail++] = slab_get_obj(cachep, slab); > - } > - > - return batchcount; > -} > - > -static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags) > -{ > - int batchcount; > - struct kmem_cache_node *n; > - struct array_cache *ac, *shared; > - int node; > - void *list = NULL; > - struct slab *slab; > - > - check_irq_off(); > - node = numa_mem_id(); > - > - ac = cpu_cache_get(cachep); > - batchcount = ac->batchcount; > - if (!ac->touched && batchcount > BATCHREFILL_LIMIT) { > - /* > - * If there was little recent activity on this cache, then > - * perform only a partial refill. Otherwise we could generate > - * refill bouncing. > - */ > - batchcount = BATCHREFILL_LIMIT; > - } > - n = get_node(cachep, node); > - > - BUG_ON(ac->avail > 0 || !n); > - shared = READ_ONCE(n->shared); > - if (!n->free_objects && (!shared || !shared->avail)) > - goto direct_grow; > - > - raw_spin_lock(&n->list_lock); > - shared = READ_ONCE(n->shared); > - > - /* See if we can refill from the shared array */ > - if (shared && transfer_objects(ac, shared, batchcount)) { > - shared->touched = 1; > - goto alloc_done; > - } > - > - while (batchcount > 0) { > - /* Get slab alloc is to come from. */ > - slab = get_first_slab(n, false); > - if (!slab) > - goto must_grow; > - > - check_spinlock_acquired(cachep); > - > - batchcount = alloc_block(cachep, ac, slab, batchcount); > - fixup_slab_list(cachep, n, slab, &list); > - } > - > -must_grow: > - n->free_objects -= ac->avail; > -alloc_done: > - raw_spin_unlock(&n->list_lock); > - fixup_objfreelist_debug(cachep, &list); > - > -direct_grow: > - if (unlikely(!ac->avail)) { > - /* Check if we can use obj in pfmemalloc slab */ > - if (sk_memalloc_socks()) { > - void *obj = cache_alloc_pfmemalloc(cachep, n, flags); > - > - if (obj) > - return obj; > - } > - > - slab = cache_grow_begin(cachep, gfp_exact_node(flags), node); > - > - /* > - * cache_grow_begin() can reenable interrupts, > - * then ac could change. > - */ > - ac = cpu_cache_get(cachep); > - if (!ac->avail && slab) > - alloc_block(cachep, ac, slab, batchcount); > - cache_grow_end(cachep, slab); > - > - if (!ac->avail) > - return NULL; > - } > - ac->touched = 1; > - > - return ac->entry[--ac->avail]; > -} > - > -#if DEBUG > -static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, > - gfp_t flags, void *objp, unsigned long caller) > -{ > - WARN_ON_ONCE(cachep->ctor && (flags & __GFP_ZERO)); > - if (!objp || is_kfence_address(objp)) > - return objp; > - if (cachep->flags & SLAB_POISON) { > - check_poison_obj(cachep, objp); > - slab_kernel_map(cachep, objp, 1); > - poison_obj(cachep, objp, POISON_INUSE); > - } > - if (cachep->flags & SLAB_STORE_USER) > - *dbg_userword(cachep, objp) = (void *)caller; > - > - if (cachep->flags & SLAB_RED_ZONE) { > - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE || > - *dbg_redzone2(cachep, objp) != RED_INACTIVE) { > - slab_error(cachep, "double free, or memory outside object was overwritten"); > - pr_err("%px: redzone 1:0x%llx, redzone 2:0x%llx\n", > - objp, *dbg_redzone1(cachep, objp), > - *dbg_redzone2(cachep, objp)); > - } > - *dbg_redzone1(cachep, objp) = RED_ACTIVE; > - *dbg_redzone2(cachep, objp) = RED_ACTIVE; > - } > - > - objp += obj_offset(cachep); > - if (cachep->ctor && cachep->flags & SLAB_POISON) > - cachep->ctor(objp); > - if ((unsigned long)objp & (arch_slab_minalign() - 1)) { > - pr_err("0x%px: not aligned to arch_slab_minalign()=%u\n", objp, > - arch_slab_minalign()); > - } > - return objp; > -} > -#else > -#define cache_alloc_debugcheck_after(a, b, objp, d) (objp) > -#endif > - > -static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - void *objp; > - struct array_cache *ac; > - > - check_irq_off(); > - > - ac = cpu_cache_get(cachep); > - if (likely(ac->avail)) { > - ac->touched = 1; > - objp = ac->entry[--ac->avail]; > - > - STATS_INC_ALLOCHIT(cachep); > - goto out; > - } > - > - STATS_INC_ALLOCMISS(cachep); > - objp = cache_alloc_refill(cachep, flags); > - /* > - * the 'ac' may be updated by cache_alloc_refill(), > - * and kmemleak_erase() requires its correct value. > - */ > - ac = cpu_cache_get(cachep); > - > -out: > - /* > - * To avoid a false negative, if an object that is in one of the > - * per-CPU caches is leaked, we need to make sure kmemleak doesn't > - * treat the array pointers as a reference to the object. > - */ > - if (objp) > - kmemleak_erase(&ac->entry[ac->avail]); > - return objp; > -} > - > -#ifdef CONFIG_NUMA > -static void *____cache_alloc_node(struct kmem_cache *, gfp_t, int); > - > -/* > - * Try allocating on another node if PFA_SPREAD_SLAB is a mempolicy is set. > - * > - * If we are in_interrupt, then process context, including cpusets and > - * mempolicy, may not apply and should not be used for allocation policy. > - */ > -static void *alternate_node_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - int nid_alloc, nid_here; > - > - if (in_interrupt() || (flags & __GFP_THISNODE)) > - return NULL; > - nid_alloc = nid_here = numa_mem_id(); > - if (cpuset_do_slab_mem_spread() && (cachep->flags & SLAB_MEM_SPREAD)) > - nid_alloc = cpuset_slab_spread_node(); > - else if (current->mempolicy) > - nid_alloc = mempolicy_slab_node(); > - if (nid_alloc != nid_here) > - return ____cache_alloc_node(cachep, flags, nid_alloc); > - return NULL; > -} > - > -/* > - * Fallback function if there was no memory available and no objects on a > - * certain node and fall back is permitted. First we scan all the > - * available node for available objects. If that fails then we > - * perform an allocation without specifying a node. This allows the page > - * allocator to do its reclaim / fallback magic. We then insert the > - * slab into the proper nodelist and then allocate from it. > - */ > -static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags) > -{ > - struct zonelist *zonelist; > - struct zoneref *z; > - struct zone *zone; > - enum zone_type highest_zoneidx = gfp_zone(flags); > - void *obj = NULL; > - struct slab *slab; > - int nid; > - unsigned int cpuset_mems_cookie; > - > - if (flags & __GFP_THISNODE) > - return NULL; > - > -retry_cpuset: > - cpuset_mems_cookie = read_mems_allowed_begin(); > - zonelist = node_zonelist(mempolicy_slab_node(), flags); > - > -retry: > - /* > - * Look through allowed nodes for objects available > - * from existing per node queues. > - */ > - for_each_zone_zonelist(zone, z, zonelist, highest_zoneidx) { > - nid = zone_to_nid(zone); > - > - if (cpuset_zone_allowed(zone, flags) && > - get_node(cache, nid) && > - get_node(cache, nid)->free_objects) { > - obj = ____cache_alloc_node(cache, > - gfp_exact_node(flags), nid); > - if (obj) > - break; > - } > - } > - > - if (!obj) { > - /* > - * This allocation will be performed within the constraints > - * of the current cpuset / memory policy requirements. > - * We may trigger various forms of reclaim on the allowed > - * set and go into memory reserves if necessary. > - */ > - slab = cache_grow_begin(cache, flags, numa_mem_id()); > - cache_grow_end(cache, slab); > - if (slab) { > - nid = slab_nid(slab); > - obj = ____cache_alloc_node(cache, > - gfp_exact_node(flags), nid); > - > - /* > - * Another processor may allocate the objects in > - * the slab since we are not holding any locks. > - */ > - if (!obj) > - goto retry; > - } > - } > - > - if (unlikely(!obj && read_mems_allowed_retry(cpuset_mems_cookie))) > - goto retry_cpuset; > - return obj; > -} > - > -/* > - * An interface to enable slab creation on nodeid > - */ > -static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, > - int nodeid) > -{ > - struct slab *slab; > - struct kmem_cache_node *n; > - void *obj = NULL; > - void *list = NULL; > - > - VM_BUG_ON(nodeid < 0 || nodeid >= MAX_NUMNODES); > - n = get_node(cachep, nodeid); > - BUG_ON(!n); > - > - check_irq_off(); > - raw_spin_lock(&n->list_lock); > - slab = get_first_slab(n, false); > - if (!slab) > - goto must_grow; > - > - check_spinlock_acquired_node(cachep, nodeid); > - > - STATS_INC_NODEALLOCS(cachep); > - STATS_INC_ACTIVE(cachep); > - STATS_SET_HIGH(cachep); > - > - BUG_ON(slab->active == cachep->num); > - > - obj = slab_get_obj(cachep, slab); > - n->free_objects--; > - > - fixup_slab_list(cachep, n, slab, &list); > - > - raw_spin_unlock(&n->list_lock); > - fixup_objfreelist_debug(cachep, &list); > - return obj; > - > -must_grow: > - raw_spin_unlock(&n->list_lock); > - slab = cache_grow_begin(cachep, gfp_exact_node(flags), nodeid); > - if (slab) { > - /* This slab isn't counted yet so don't update free_objects */ > - obj = slab_get_obj(cachep, slab); > - } > - cache_grow_end(cachep, slab); > - > - return obj ? obj : fallback_alloc(cachep, flags); > -} > - > -static __always_inline void * > -__do_cache_alloc(struct kmem_cache *cachep, gfp_t flags, int nodeid) > -{ > - void *objp = NULL; > - int slab_node = numa_mem_id(); > - > - if (nodeid == NUMA_NO_NODE) { > - if (current->mempolicy || cpuset_do_slab_mem_spread()) { > - objp = alternate_node_alloc(cachep, flags); > - if (objp) > - goto out; > - } > - /* > - * Use the locally cached objects if possible. > - * However ____cache_alloc does not allow fallback > - * to other nodes. It may fail while we still have > - * objects on other nodes available. > - */ > - objp = ____cache_alloc(cachep, flags); > - nodeid = slab_node; > - } else if (nodeid == slab_node) { > - objp = ____cache_alloc(cachep, flags); > - } else if (!get_node(cachep, nodeid)) { > - /* Node not bootstrapped yet */ > - objp = fallback_alloc(cachep, flags); > - goto out; > - } > - > - /* > - * We may just have run out of memory on the local node. > - * ____cache_alloc_node() knows how to locate memory on other nodes > - */ > - if (!objp) > - objp = ____cache_alloc_node(cachep, flags, nodeid); > -out: > - return objp; > -} > -#else > - > -static __always_inline void * > -__do_cache_alloc(struct kmem_cache *cachep, gfp_t flags, int nodeid __maybe_unused) > -{ > - return ____cache_alloc(cachep, flags); > -} > - > -#endif /* CONFIG_NUMA */ > - > -static __always_inline void * > -slab_alloc_node(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags, > - int nodeid, size_t orig_size, unsigned long caller) > -{ > - unsigned long save_flags; > - void *objp; > - struct obj_cgroup *objcg = NULL; > - bool init = false; > - > - flags &= gfp_allowed_mask; > - cachep = slab_pre_alloc_hook(cachep, lru, &objcg, 1, flags); > - if (unlikely(!cachep)) > - return NULL; > - > - objp = kfence_alloc(cachep, orig_size, flags); > - if (unlikely(objp)) > - goto out; > - > - local_irq_save(save_flags); > - objp = __do_cache_alloc(cachep, flags, nodeid); > - local_irq_restore(save_flags); > - objp = cache_alloc_debugcheck_after(cachep, flags, objp, caller); > - prefetchw(objp); > - init = slab_want_init_on_alloc(flags, cachep); > - > -out: > - slab_post_alloc_hook(cachep, objcg, flags, 1, &objp, init, > - cachep->object_size); > - return objp; > -} > - > -static __always_inline void * > -slab_alloc(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags, > - size_t orig_size, unsigned long caller) > -{ > - return slab_alloc_node(cachep, lru, flags, NUMA_NO_NODE, orig_size, > - caller); > -} > - > -/* > - * Caller needs to acquire correct kmem_cache_node's list_lock > - * @list: List of detached free slabs should be freed by caller > - */ > -static void free_block(struct kmem_cache *cachep, void **objpp, > - int nr_objects, int node, struct list_head *list) > -{ > - int i; > - struct kmem_cache_node *n = get_node(cachep, node); > - struct slab *slab; > - > - n->free_objects += nr_objects; > - > - for (i = 0; i < nr_objects; i++) { > - void *objp; > - struct slab *slab; > - > - objp = objpp[i]; > - > - slab = virt_to_slab(objp); > - list_del(&slab->slab_list); > - check_spinlock_acquired_node(cachep, node); > - slab_put_obj(cachep, slab, objp); > - STATS_DEC_ACTIVE(cachep); > - > - /* fixup slab chains */ > - if (slab->active == 0) { > - list_add(&slab->slab_list, &n->slabs_free); > - n->free_slabs++; > - } else { > - /* Unconditionally move a slab to the end of the > - * partial list on free - maximum time for the > - * other objects to be freed, too. > - */ > - list_add_tail(&slab->slab_list, &n->slabs_partial); > - } > - } > - > - while (n->free_objects > n->free_limit && !list_empty(&n->slabs_free)) { > - n->free_objects -= cachep->num; > - > - slab = list_last_entry(&n->slabs_free, struct slab, slab_list); > - list_move(&slab->slab_list, list); > - n->free_slabs--; > - n->total_slabs--; > - } > -} > - > -static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) > -{ > - int batchcount; > - struct kmem_cache_node *n; > - int node = numa_mem_id(); > - LIST_HEAD(list); > - > - batchcount = ac->batchcount; > - > - check_irq_off(); > - n = get_node(cachep, node); > - raw_spin_lock(&n->list_lock); > - if (n->shared) { > - struct array_cache *shared_array = n->shared; > - int max = shared_array->limit - shared_array->avail; > - if (max) { > - if (batchcount > max) > - batchcount = max; > - memcpy(&(shared_array->entry[shared_array->avail]), > - ac->entry, sizeof(void *) * batchcount); > - shared_array->avail += batchcount; > - goto free_done; > - } > - } > - > - free_block(cachep, ac->entry, batchcount, node, &list); > -free_done: > -#if STATS > - { > - int i = 0; > - struct slab *slab; > - > - list_for_each_entry(slab, &n->slabs_free, slab_list) { > - BUG_ON(slab->active); > - > - i++; > - } > - STATS_SET_FREEABLE(cachep, i); > - } > -#endif > - raw_spin_unlock(&n->list_lock); > - ac->avail -= batchcount; > - memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail); > - slabs_destroy(cachep, &list); > -} > - > -/* > - * Release an obj back to its cache. If the obj has a constructed state, it must > - * be in this state _before_ it is released. Called with disabled ints. > - */ > -static __always_inline void __cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - bool init; > - > - memcg_slab_free_hook(cachep, virt_to_slab(objp), &objp, 1); > - > - if (is_kfence_address(objp)) { > - kmemleak_free_recursive(objp, cachep->flags); > - __kfence_free(objp); > - return; > - } > - > - /* > - * As memory initialization might be integrated into KASAN, > - * kasan_slab_free and initialization memset must be > - * kept together to avoid discrepancies in behavior. > - */ > - init = slab_want_init_on_free(cachep); > - if (init && !kasan_has_integrated_init()) > - memset(objp, 0, cachep->object_size); > - /* KASAN might put objp into memory quarantine, delaying its reuse. */ > - if (kasan_slab_free(cachep, objp, init)) > - return; > - > - /* Use KCSAN to help debug racy use-after-free. */ > - if (!(cachep->flags & SLAB_TYPESAFE_BY_RCU)) > - __kcsan_check_access(objp, cachep->object_size, > - KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ASSERT); > - > - ___cache_free(cachep, objp, caller); > -} > - > -void ___cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - struct array_cache *ac = cpu_cache_get(cachep); > - > - check_irq_off(); > - kmemleak_free_recursive(objp, cachep->flags); > - objp = cache_free_debugcheck(cachep, objp, caller); > - > - /* > - * Skip calling cache_free_alien() when the platform is not numa. > - * This will avoid cache misses that happen while accessing slabp (which > - * is per page memory reference) to get nodeid. Instead use a global > - * variable to skip the call, which is mostly likely to be present in > - * the cache. > - */ > - if (nr_online_nodes > 1 && cache_free_alien(cachep, objp)) > - return; > - > - if (ac->avail < ac->limit) { > - STATS_INC_FREEHIT(cachep); > - } else { > - STATS_INC_FREEMISS(cachep); > - cache_flusharray(cachep, ac); > - } > - > - if (sk_memalloc_socks()) { > - struct slab *slab = virt_to_slab(objp); > - > - if (unlikely(slab_test_pfmemalloc(slab))) { > - cache_free_pfmemalloc(cachep, slab, objp); > - return; > - } > - } > - > - __free_one(ac, objp); > -} > - > -static __always_inline > -void *__kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, > - gfp_t flags) > -{ > - void *ret = slab_alloc(cachep, lru, flags, cachep->object_size, _RET_IP_); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, cachep, flags, NUMA_NO_NODE); > - > - return ret; > -} > - > -void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - return __kmem_cache_alloc_lru(cachep, NULL, flags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc); > - > -void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, > - gfp_t flags) > -{ > - return __kmem_cache_alloc_lru(cachep, lru, flags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_lru); > - > -static __always_inline void > -cache_alloc_debugcheck_after_bulk(struct kmem_cache *s, gfp_t flags, > - size_t size, void **p, unsigned long caller) > -{ > - size_t i; > - > - for (i = 0; i < size; i++) > - p[i] = cache_alloc_debugcheck_after(s, flags, p[i], caller); > -} > - > -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, > - void **p) > -{ > - struct obj_cgroup *objcg = NULL; > - unsigned long irqflags; > - size_t i; > - > - s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); > - if (!s) > - return 0; > - > - local_irq_save(irqflags); > - for (i = 0; i < size; i++) { > - void *objp = kfence_alloc(s, s->object_size, flags) ?: > - __do_cache_alloc(s, flags, NUMA_NO_NODE); > - > - if (unlikely(!objp)) > - goto error; > - p[i] = objp; > - } > - local_irq_restore(irqflags); > - > - cache_alloc_debugcheck_after_bulk(s, flags, size, p, _RET_IP_); > - > - /* > - * memcg and kmem_cache debug support and memory initialization. > - * Done outside of the IRQ disabled section. > - */ > - slab_post_alloc_hook(s, objcg, flags, size, p, > - slab_want_init_on_alloc(flags, s), s->object_size); > - /* FIXME: Trace call missing. Christoph would like a bulk variant */ > - return size; > -error: > - local_irq_restore(irqflags); > - cache_alloc_debugcheck_after_bulk(s, flags, i, p, _RET_IP_); > - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); > - kmem_cache_free_bulk(s, i, p); > - return 0; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_bulk); > - > -/** > - * kmem_cache_alloc_node - Allocate an object on the specified node > - * @cachep: The cache to allocate from. > - * @flags: See kmalloc(). > - * @nodeid: node number of the target node. > - * > - * Identical to kmem_cache_alloc but it will allocate memory on the given > - * node, which can improve the performance for cpu bound structures. > - * > - * Fallback to other node is possible if __GFP_THISNODE is not set. > - * > - * Return: pointer to the new object or %NULL in case of error > - */ > -void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) > -{ > - void *ret = slab_alloc_node(cachep, NULL, flags, nodeid, cachep->object_size, _RET_IP_); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, cachep, flags, nodeid); > - > - return ret; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_node); > - > -void *__kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, > - int nodeid, size_t orig_size, > - unsigned long caller) > -{ > - return slab_alloc_node(cachep, NULL, flags, nodeid, > - orig_size, caller); > -} > - > -#ifdef CONFIG_PRINTK > -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) > -{ > - struct kmem_cache *cachep; > - unsigned int objnr; > - void *objp; > - > - kpp->kp_ptr = object; > - kpp->kp_slab = slab; > - cachep = slab->slab_cache; > - kpp->kp_slab_cache = cachep; > - objp = object - obj_offset(cachep); > - kpp->kp_data_offset = obj_offset(cachep); > - slab = virt_to_slab(objp); > - objnr = obj_to_index(cachep, slab, objp); > - objp = index_to_obj(cachep, slab, objnr); > - kpp->kp_objp = objp; > - if (DEBUG && cachep->flags & SLAB_STORE_USER) > - kpp->kp_ret = *dbg_userword(cachep, objp); > -} > -#endif > - > -static __always_inline > -void __do_kmem_cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - unsigned long flags; > - > - local_irq_save(flags); > - debug_check_no_locks_freed(objp, cachep->object_size); > - if (!(cachep->flags & SLAB_DEBUG_OBJECTS)) > - debug_check_no_obj_freed(objp, cachep->object_size); > - __cache_free(cachep, objp, caller); > - local_irq_restore(flags); > -} > - > -void __kmem_cache_free(struct kmem_cache *cachep, void *objp, > - unsigned long caller) > -{ > - __do_kmem_cache_free(cachep, objp, caller); > -} > - > -/** > - * kmem_cache_free - Deallocate an object > - * @cachep: The cache the allocation was from. > - * @objp: The previously allocated object. > - * > - * Free an object which was previously allocated from this > - * cache. > - */ > -void kmem_cache_free(struct kmem_cache *cachep, void *objp) > -{ > - cachep = cache_from_obj(cachep, objp); > - if (!cachep) > - return; > - > - trace_kmem_cache_free(_RET_IP_, objp, cachep); > - __do_kmem_cache_free(cachep, objp, _RET_IP_); > -} > -EXPORT_SYMBOL(kmem_cache_free); > - > -void kmem_cache_free_bulk(struct kmem_cache *orig_s, size_t size, void **p) > -{ > - unsigned long flags; > - > - local_irq_save(flags); > - for (int i = 0; i < size; i++) { > - void *objp = p[i]; > - struct kmem_cache *s; > - > - if (!orig_s) { > - struct folio *folio = virt_to_folio(objp); > - > - /* called via kfree_bulk */ > - if (!folio_test_slab(folio)) { > - local_irq_restore(flags); > - free_large_kmalloc(folio, objp); > - local_irq_save(flags); > - continue; > - } > - s = folio_slab(folio)->slab_cache; > - } else { > - s = cache_from_obj(orig_s, objp); > - } > - > - if (!s) > - continue; > - > - debug_check_no_locks_freed(objp, s->object_size); > - if (!(s->flags & SLAB_DEBUG_OBJECTS)) > - debug_check_no_obj_freed(objp, s->object_size); > - > - __cache_free(s, objp, _RET_IP_); > - } > - local_irq_restore(flags); > - > - /* FIXME: add tracing */ > -} > -EXPORT_SYMBOL(kmem_cache_free_bulk); > - > -/* > - * This initializes kmem_cache_node or resizes various caches for all nodes. > - */ > -static int setup_kmem_cache_nodes(struct kmem_cache *cachep, gfp_t gfp) > -{ > - int ret; > - int node; > - struct kmem_cache_node *n; > - > - for_each_online_node(node) { > - ret = setup_kmem_cache_node(cachep, node, gfp, true); > - if (ret) > - goto fail; > - > - } > - > - return 0; > - > -fail: > - if (!cachep->list.next) { > - /* Cache is not active yet. Roll back what we did */ > - node--; > - while (node >= 0) { > - n = get_node(cachep, node); > - if (n) { > - kfree(n->shared); > - free_alien_cache(n->alien); > - kfree(n); > - cachep->node[node] = NULL; > - } > - node--; > - } > - } > - return -ENOMEM; > -} > - > -/* Always called with the slab_mutex held */ > -static int do_tune_cpucache(struct kmem_cache *cachep, int limit, > - int batchcount, int shared, gfp_t gfp) > -{ > - struct array_cache __percpu *cpu_cache, *prev; > - int cpu; > - > - cpu_cache = alloc_kmem_cache_cpus(cachep, limit, batchcount); > - if (!cpu_cache) > - return -ENOMEM; > - > - prev = cachep->cpu_cache; > - cachep->cpu_cache = cpu_cache; > - /* > - * Without a previous cpu_cache there's no need to synchronize remote > - * cpus, so skip the IPIs. > - */ > - if (prev) > - kick_all_cpus_sync(); > - > - check_irq_on(); > - cachep->batchcount = batchcount; > - cachep->limit = limit; > - cachep->shared = shared; > - > - if (!prev) > - goto setup_node; > - > - for_each_online_cpu(cpu) { > - LIST_HEAD(list); > - int node; > - struct kmem_cache_node *n; > - struct array_cache *ac = per_cpu_ptr(prev, cpu); > - > - node = cpu_to_mem(cpu); > - n = get_node(cachep, node); > - raw_spin_lock_irq(&n->list_lock); > - free_block(cachep, ac->entry, ac->avail, node, &list); > - raw_spin_unlock_irq(&n->list_lock); > - slabs_destroy(cachep, &list); > - } > - free_percpu(prev); > - > -setup_node: > - return setup_kmem_cache_nodes(cachep, gfp); > -} > - > -/* Called with slab_mutex held always */ > -static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp) > -{ > - int err; > - int limit = 0; > - int shared = 0; > - int batchcount = 0; > - > - err = cache_random_seq_create(cachep, cachep->num, gfp); > - if (err) > - goto end; > - > - /* > - * The head array serves three purposes: > - * - create a LIFO ordering, i.e. return objects that are cache-warm > - * - reduce the number of spinlock operations. > - * - reduce the number of linked list operations on the slab and > - * bufctl chains: array operations are cheaper. > - * The numbers are guessed, we should auto-tune as described by > - * Bonwick. > - */ > - if (cachep->size > 131072) > - limit = 1; > - else if (cachep->size > PAGE_SIZE) > - limit = 8; > - else if (cachep->size > 1024) > - limit = 24; > - else if (cachep->size > 256) > - limit = 54; > - else > - limit = 120; > - > - /* > - * CPU bound tasks (e.g. network routing) can exhibit cpu bound > - * allocation behaviour: Most allocs on one cpu, most free operations > - * on another cpu. For these cases, an efficient object passing between > - * cpus is necessary. This is provided by a shared array. The array > - * replaces Bonwick's magazine layer. > - * On uniprocessor, it's functionally equivalent (but less efficient) > - * to a larger limit. Thus disabled by default. > - */ > - shared = 0; > - if (cachep->size <= PAGE_SIZE && num_possible_cpus() > 1) > - shared = 8; > - > -#if DEBUG > - /* > - * With debugging enabled, large batchcount lead to excessively long > - * periods with disabled local interrupts. Limit the batchcount > - */ > - if (limit > 32) > - limit = 32; > -#endif > - batchcount = (limit + 1) / 2; > - err = do_tune_cpucache(cachep, limit, batchcount, shared, gfp); > -end: > - if (err) > - pr_err("enable_cpucache failed for %s, error %d\n", > - cachep->name, -err); > - return err; > -} > - > -/* > - * Drain an array if it contains any elements taking the node lock only if > - * necessary. Note that the node listlock also protects the array_cache > - * if drain_array() is used on the shared array. > - */ > -static void drain_array(struct kmem_cache *cachep, struct kmem_cache_node *n, > - struct array_cache *ac, int node) > -{ > - LIST_HEAD(list); > - > - /* ac from n->shared can be freed if we don't hold the slab_mutex. */ > - check_mutex_acquired(); > - > - if (!ac || !ac->avail) > - return; > - > - if (ac->touched) { > - ac->touched = 0; > - return; > - } > - > - raw_spin_lock_irq(&n->list_lock); > - drain_array_locked(cachep, ac, node, false, &list); > - raw_spin_unlock_irq(&n->list_lock); > - > - slabs_destroy(cachep, &list); > -} > - > -/** > - * cache_reap - Reclaim memory from caches. > - * @w: work descriptor > - * > - * Called from workqueue/eventd every few seconds. > - * Purpose: > - * - clear the per-cpu caches for this CPU. > - * - return freeable pages to the main free memory pool. > - * > - * If we cannot acquire the cache chain mutex then just give up - we'll try > - * again on the next iteration. > - */ > -static void cache_reap(struct work_struct *w) > -{ > - struct kmem_cache *searchp; > - struct kmem_cache_node *n; > - int node = numa_mem_id(); > - struct delayed_work *work = to_delayed_work(w); > - > - if (!mutex_trylock(&slab_mutex)) > - /* Give up. Setup the next iteration. */ > - goto out; > - > - list_for_each_entry(searchp, &slab_caches, list) { > - check_irq_on(); > - > - /* > - * We only take the node lock if absolutely necessary and we > - * have established with reasonable certainty that > - * we can do some work if the lock was obtained. > - */ > - n = get_node(searchp, node); > - > - reap_alien(searchp, n); > - > - drain_array(searchp, n, cpu_cache_get(searchp), node); > - > - /* > - * These are racy checks but it does not matter > - * if we skip one check or scan twice. > - */ > - if (time_after(n->next_reap, jiffies)) > - goto next; > - > - n->next_reap = jiffies + REAPTIMEOUT_NODE; > - > - drain_array(searchp, n, n->shared, node); > - > - if (n->free_touched) > - n->free_touched = 0; > - else { > - int freed; > - > - freed = drain_freelist(searchp, n, (n->free_limit + > - 5 * searchp->num - 1) / (5 * searchp->num)); > - STATS_ADD_REAPED(searchp, freed); > - } > -next: > - cond_resched(); > - } > - check_irq_on(); > - mutex_unlock(&slab_mutex); > - next_reap_node(); > -out: > - /* Set up the next iteration */ > - schedule_delayed_work_on(smp_processor_id(), work, > - round_jiffies_relative(REAPTIMEOUT_AC)); > -} > - > -void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo) > -{ > - unsigned long active_objs, num_objs, active_slabs; > - unsigned long total_slabs = 0, free_objs = 0, shared_avail = 0; > - unsigned long free_slabs = 0; > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(cachep, node, n) { > - check_irq_on(); > - raw_spin_lock_irq(&n->list_lock); > - > - total_slabs += n->total_slabs; > - free_slabs += n->free_slabs; > - free_objs += n->free_objects; > - > - if (n->shared) > - shared_avail += n->shared->avail; > - > - raw_spin_unlock_irq(&n->list_lock); > - } > - num_objs = total_slabs * cachep->num; > - active_slabs = total_slabs - free_slabs; > - active_objs = num_objs - free_objs; > - > - sinfo->active_objs = active_objs; > - sinfo->num_objs = num_objs; > - sinfo->active_slabs = active_slabs; > - sinfo->num_slabs = total_slabs; > - sinfo->shared_avail = shared_avail; > - sinfo->limit = cachep->limit; > - sinfo->batchcount = cachep->batchcount; > - sinfo->shared = cachep->shared; > - sinfo->objects_per_slab = cachep->num; > - sinfo->cache_order = cachep->gfporder; > -} > - > -void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *cachep) > -{ > -#if STATS > - { /* node stats */ > - unsigned long high = cachep->high_mark; > - unsigned long allocs = cachep->num_allocations; > - unsigned long grown = cachep->grown; > - unsigned long reaped = cachep->reaped; > - unsigned long errors = cachep->errors; > - unsigned long max_freeable = cachep->max_freeable; > - unsigned long node_allocs = cachep->node_allocs; > - unsigned long node_frees = cachep->node_frees; > - unsigned long overflows = cachep->node_overflow; > - > - seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu %4lu %4lu %4lu %4lu %4lu", > - allocs, high, grown, > - reaped, errors, max_freeable, node_allocs, > - node_frees, overflows); > - } > - /* cpu stats */ > - { > - unsigned long allochit = atomic_read(&cachep->allochit); > - unsigned long allocmiss = atomic_read(&cachep->allocmiss); > - unsigned long freehit = atomic_read(&cachep->freehit); > - unsigned long freemiss = atomic_read(&cachep->freemiss); > - > - seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu", > - allochit, allocmiss, freehit, freemiss); > - } > -#endif > -} > - > -#define MAX_SLABINFO_WRITE 128 > -/** > - * slabinfo_write - Tuning for the slab allocator > - * @file: unused > - * @buffer: user buffer > - * @count: data length > - * @ppos: unused > - * > - * Return: %0 on success, negative error code otherwise. > - */ > -ssize_t slabinfo_write(struct file *file, const char __user *buffer, > - size_t count, loff_t *ppos) > -{ > - char kbuf[MAX_SLABINFO_WRITE + 1], *tmp; > - int limit, batchcount, shared, res; > - struct kmem_cache *cachep; > - > - if (count > MAX_SLABINFO_WRITE) > - return -EINVAL; > - if (copy_from_user(&kbuf, buffer, count)) > - return -EFAULT; > - kbuf[MAX_SLABINFO_WRITE] = '\0'; > - > - tmp = strchr(kbuf, ' '); > - if (!tmp) > - return -EINVAL; > - *tmp = '\0'; > - tmp++; > - if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3) > - return -EINVAL; > - > - /* Find the cache in the chain of caches. */ > - mutex_lock(&slab_mutex); > - res = -EINVAL; > - list_for_each_entry(cachep, &slab_caches, list) { > - if (!strcmp(cachep->name, kbuf)) { > - if (limit < 1 || batchcount < 1 || > - batchcount > limit || shared < 0) { > - res = 0; > - } else { > - res = do_tune_cpucache(cachep, limit, > - batchcount, shared, > - GFP_KERNEL); > - } > - break; > - } > - } > - mutex_unlock(&slab_mutex); > - if (res >= 0) > - res = count; > - return res; > -} > - > -#ifdef CONFIG_HARDENED_USERCOPY > -/* > - * Rejects incorrectly sized objects and objects that are to be copied > - * to/from userspace but do not fall entirely within the containing slab > - * cache's usercopy region. > - * > - * Returns NULL if check passes, otherwise const char * to name of cache > - * to indicate an error. > - */ > -void __check_heap_object(const void *ptr, unsigned long n, > - const struct slab *slab, bool to_user) > -{ > - struct kmem_cache *cachep; > - unsigned int objnr; > - unsigned long offset; > - > - ptr = kasan_reset_tag(ptr); > - > - /* Find and validate object. */ > - cachep = slab->slab_cache; > - objnr = obj_to_index(cachep, slab, (void *)ptr); > - BUG_ON(objnr >= cachep->num); > - > - /* Find offset within object. */ > - if (is_kfence_address(ptr)) > - offset = ptr - kfence_object_start(ptr); > - else > - offset = ptr - index_to_obj(cachep, slab, objnr) - obj_offset(cachep); > - > - /* Allow address range falling entirely within usercopy region. */ > - if (offset >= cachep->useroffset && > - offset - cachep->useroffset <= cachep->usersize && > - n <= cachep->useroffset - offset + cachep->usersize) > - return; > - > - usercopy_abort("SLAB object", cachep->name, to_user, offset, n); > -} > -#endif /* CONFIG_HARDENED_USERCOPY */ > diff --git a/mm/slab.h b/mm/slab.h > index 43966aa5fadf..53e97b7640e9 100644 > --- a/mm/slab.h > +++ b/mm/slab.h > @@ -9,60 +9,12 @@ > struct slab { > unsigned long __page_flags; > > -#if defined(CONFIG_SLAB) > - > - struct kmem_cache *slab_cache; > - union { > - struct { > - struct list_head slab_list; > - void *freelist; /* array of free object indexes */ > - void *s_mem; /* first object */ > - }; > - struct rcu_head rcu_head; > - }; > - unsigned int active; > - > -#elif defined(CONFIG_SLUB) > - > - struct kmem_cache *slab_cache; > - union { > - struct { > - union { > - struct list_head slab_list; > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - struct { > - struct slab *next; > - int slabs; /* Nr of slabs left */ > - }; > -#endif > - }; > - /* Double-word boundary */ > - void *freelist; /* first free object */ > - union { > - unsigned long counters; > - struct { > - unsigned inuse:16; > - unsigned objects:15; > - unsigned frozen:1; > - }; > - }; > - }; > - struct rcu_head rcu_head; > - }; > - unsigned int __unused; > - > -#elif defined(CONFIG_SLOB) > - > struct list_head slab_list; > void *__unused_1; > void *freelist; /* first free block */ > long units; > unsigned int __unused_2; > > -#else > -#error "Unexpected slab allocator configured" > -#endif > - > atomic_t __page_refcount; > #ifdef CONFIG_MEMCG > unsigned long memcg_data; > @@ -72,20 +24,13 @@ struct slab { > #define SLAB_MATCH(pg, sl) \ > static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl)) > SLAB_MATCH(flags, __page_flags); > -#ifndef CONFIG_SLOB > -SLAB_MATCH(compound_head, slab_cache); /* Ensure bit 0 is clear */ > -#else > SLAB_MATCH(compound_head, slab_list); /* Ensure bit 0 is clear */ > -#endif > SLAB_MATCH(_refcount, __page_refcount); > #ifdef CONFIG_MEMCG > SLAB_MATCH(memcg_data, memcg_data); > #endif > #undef SLAB_MATCH > static_assert(sizeof(struct slab) <= sizeof(struct page)); > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && defined(CONFIG_SLUB) > -static_assert(IS_ALIGNED(offsetof(struct slab, freelist), 2*sizeof(void *))); > -#endif > > /** > * folio_slab - Converts from folio to slab. > @@ -200,7 +145,6 @@ static inline size_t slab_size(const struct slab *slab) > return PAGE_SIZE << slab_order(slab); > } > > -#ifdef CONFIG_SLOB > /* > * Common fields provided in kmem_cache by all slab allocators > * This struct is either used directly by the allocator (SLOB) > @@ -223,16 +167,6 @@ struct kmem_cache { > struct list_head list; /* List of all slab caches on the system */ > }; > > -#endif /* CONFIG_SLOB */ > - > -#ifdef CONFIG_SLAB > -#include <linux/slab_def.h> > -#endif > - > -#ifdef CONFIG_SLUB > -#include <linux/slub_def.h> > -#endif > - > #include <linux/memcontrol.h> > #include <linux/fault-inject.h> > #include <linux/kasan.h> > @@ -268,26 +202,6 @@ extern struct list_head slab_caches; > /* The slab cache that manages slab cache information */ > extern struct kmem_cache *kmem_cache; > > -/* A table of kmalloc cache names and sizes */ > -extern const struct kmalloc_info_struct { > - const char *name[NR_KMALLOC_TYPES]; > - unsigned int size; > -} kmalloc_info[]; > - > -#ifndef CONFIG_SLOB > -/* Kmalloc array related functions */ > -void setup_kmalloc_cache_index_table(void); > -void create_kmalloc_caches(slab_flags_t); > - > -/* Find the kmalloc slab corresponding for a certain size */ > -struct kmem_cache *kmalloc_slab(size_t, gfp_t); > - > -void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, > - int node, size_t orig_size, > - unsigned long caller); > -void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller); > -#endif > - > gfp_t kmalloc_fix_flags(gfp_t flags); > > /* Functions provided by the slab allocators */ > @@ -303,14 +217,6 @@ extern void create_boot_cache(struct kmem_cache *, const char *name, > int slab_unmergeable(struct kmem_cache *s); > struct kmem_cache *find_mergeable(unsigned size, unsigned align, > slab_flags_t flags, const char *name, void (*ctor)(void *)); > -#ifndef CONFIG_SLOB > -struct kmem_cache * > -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > - slab_flags_t flags, void (*ctor)(void *)); > - > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name); > -#else > static inline struct kmem_cache * > __kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > slab_flags_t flags, void (*ctor)(void *)) > @@ -321,15 +227,10 @@ static inline slab_flags_t kmem_cache_flags(unsigned int object_size, > { > return flags; > } > -#endif > > static inline bool is_kmalloc_cache(struct kmem_cache *s) > { > -#ifndef CONFIG_SLOB > - return (s->flags & SLAB_KMALLOC); > -#else > return false; > -#endif > } > > /* Legal flag mask for kmem_cache_create(), for various configurations */ > @@ -337,26 +238,9 @@ static inline bool is_kmalloc_cache(struct kmem_cache *s) > SLAB_CACHE_DMA32 | SLAB_PANIC | \ > SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS ) > > -#if defined(CONFIG_DEBUG_SLAB) > -#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) > -#elif defined(CONFIG_SLUB_DEBUG) > -#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ > - SLAB_TRACE | SLAB_CONSISTENCY_CHECKS) > -#else > #define SLAB_DEBUG_FLAGS (0) > -#endif > > -#if defined(CONFIG_SLAB) > -#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \ > - SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \ > - SLAB_ACCOUNT) > -#elif defined(CONFIG_SLUB) > -#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ > - SLAB_TEMPORARY | SLAB_ACCOUNT | \ > - SLAB_NO_USER_FLAGS | SLAB_KMALLOC) > -#else > #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE) > -#endif > > /* Common flags available with current configuration */ > #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS) > @@ -409,19 +293,6 @@ static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s) > NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B; > } > > -#ifdef CONFIG_SLUB_DEBUG > -#ifdef CONFIG_SLUB_DEBUG_ON > -DECLARE_STATIC_KEY_TRUE(slub_debug_enabled); > -#else > -DECLARE_STATIC_KEY_FALSE(slub_debug_enabled); > -#endif > -extern void print_tracking(struct kmem_cache *s, void *object); > -long validate_slab_cache(struct kmem_cache *s); > -static inline bool __slub_debug_enabled(void) > -{ > - return static_branch_unlikely(&slub_debug_enabled); > -} > -#else > static inline void print_tracking(struct kmem_cache *s, void *object) > { > } > @@ -429,7 +300,6 @@ static inline bool __slub_debug_enabled(void) > { > return false; > } > -#endif > > /* > * Returns true if any of the specified slub_debug flags is enabled for the > @@ -438,160 +308,9 @@ static inline bool __slub_debug_enabled(void) > */ > static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags) > { > - if (IS_ENABLED(CONFIG_SLUB_DEBUG)) > - VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS)); > - if (__slub_debug_enabled()) > - return s->flags & flags; > return false; > } > > -#ifdef CONFIG_MEMCG_KMEM > -/* > - * slab_objcgs - get the object cgroups vector associated with a slab > - * @slab: a pointer to the slab struct > - * > - * Returns a pointer to the object cgroups vector associated with the slab, > - * or NULL if no such vector has been associated yet. > - */ > -static inline struct obj_cgroup **slab_objcgs(struct slab *slab) > -{ > - unsigned long memcg_data = READ_ONCE(slab->memcg_data); > - > - VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), > - slab_page(slab)); > - VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, slab_page(slab)); > - > - return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); > -} > - > -int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s, > - gfp_t gfp, bool new_slab); > -void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, > - enum node_stat_item idx, int nr); > - > -static inline void memcg_free_slab_cgroups(struct slab *slab) > -{ > - kfree(slab_objcgs(slab)); > - slab->memcg_data = 0; > -} > - > -static inline size_t obj_full_size(struct kmem_cache *s) > -{ > - /* > - * For each accounted object there is an extra space which is used > - * to store obj_cgroup membership. Charge it too. > - */ > - return s->size + sizeof(struct obj_cgroup *); > -} > - > -/* > - * Returns false if the allocation should fail. > - */ > -static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, > - struct list_lru *lru, > - struct obj_cgroup **objcgp, > - size_t objects, gfp_t flags) > -{ > - struct obj_cgroup *objcg; > - > - if (!memcg_kmem_online()) > - return true; > - > - if (!(flags & __GFP_ACCOUNT) && !(s->flags & SLAB_ACCOUNT)) > - return true; > - > - objcg = get_obj_cgroup_from_current(); > - if (!objcg) > - return true; > - > - if (lru) { > - int ret; > - struct mem_cgroup *memcg; > - > - memcg = get_mem_cgroup_from_objcg(objcg); > - ret = memcg_list_lru_alloc(memcg, lru, flags); > - css_put(&memcg->css); > - > - if (ret) > - goto out; > - } > - > - if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s))) > - goto out; > - > - *objcgp = objcg; > - return true; > -out: > - obj_cgroup_put(objcg); > - return false; > -} > - > -static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, > - struct obj_cgroup *objcg, > - gfp_t flags, size_t size, > - void **p) > -{ > - struct slab *slab; > - unsigned long off; > - size_t i; > - > - if (!memcg_kmem_online() || !objcg) > - return; > - > - for (i = 0; i < size; i++) { > - if (likely(p[i])) { > - slab = virt_to_slab(p[i]); > - > - if (!slab_objcgs(slab) && > - memcg_alloc_slab_cgroups(slab, s, flags, > - false)) { > - obj_cgroup_uncharge(objcg, obj_full_size(s)); > - continue; > - } > - > - off = obj_to_index(s, slab, p[i]); > - obj_cgroup_get(objcg); > - slab_objcgs(slab)[off] = objcg; > - mod_objcg_state(objcg, slab_pgdat(slab), > - cache_vmstat_idx(s), obj_full_size(s)); > - } else { > - obj_cgroup_uncharge(objcg, obj_full_size(s)); > - } > - } > - obj_cgroup_put(objcg); > -} > - > -static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, > - void **p, int objects) > -{ > - struct obj_cgroup **objcgs; > - int i; > - > - if (!memcg_kmem_online()) > - return; > - > - objcgs = slab_objcgs(slab); > - if (!objcgs) > - return; > - > - for (i = 0; i < objects; i++) { > - struct obj_cgroup *objcg; > - unsigned int off; > - > - off = obj_to_index(s, slab, p[i]); > - objcg = objcgs[off]; > - if (!objcg) > - continue; > - > - objcgs[off] = NULL; > - obj_cgroup_uncharge(objcg, obj_full_size(s)); > - mod_objcg_state(objcg, slab_pgdat(slab), cache_vmstat_idx(s), > - -obj_full_size(s)); > - obj_cgroup_put(objcg); > - } > -} > - > -#else /* CONFIG_MEMCG_KMEM */ > static inline struct obj_cgroup **slab_objcgs(struct slab *slab) > { > return NULL; > @@ -632,90 +351,12 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, > void **p, int objects) > { > } > -#endif /* CONFIG_MEMCG_KMEM */ > - > -#ifndef CONFIG_SLOB > -static inline struct kmem_cache *virt_to_cache(const void *obj) > -{ > - struct slab *slab; > - > - slab = virt_to_slab(obj); > - if (WARN_ONCE(!slab, "%s: Object is not a Slab page!\n", > - __func__)) > - return NULL; > - return slab->slab_cache; > -} > - > -static __always_inline void account_slab(struct slab *slab, int order, > - struct kmem_cache *s, gfp_t gfp) > -{ > - if (memcg_kmem_online() && (s->flags & SLAB_ACCOUNT)) > - memcg_alloc_slab_cgroups(slab, s, gfp, true); > - > - mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), > - PAGE_SIZE << order); > -} > - > -static __always_inline void unaccount_slab(struct slab *slab, int order, > - struct kmem_cache *s) > -{ > - if (memcg_kmem_online()) > - memcg_free_slab_cgroups(slab); > - > - mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), > - -(PAGE_SIZE << order)); > -} > - > -static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) > -{ > - struct kmem_cache *cachep; > - > - if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && > - !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) > - return s; > - > - cachep = virt_to_cache(x); > - if (WARN(cachep && cachep != s, > - "%s: Wrong slab cache. %s but object is from %s\n", > - __func__, s->name, cachep->name)) > - print_tracking(cachep, x); > - return cachep; > -} > - > -void free_large_kmalloc(struct folio *folio, void *object); > - > -#endif /* CONFIG_SLOB */ > > size_t __ksize(const void *objp); > > static inline size_t slab_ksize(const struct kmem_cache *s) > { > -#ifndef CONFIG_SLUB > return s->object_size; > - > -#else /* CONFIG_SLUB */ > -# ifdef CONFIG_SLUB_DEBUG > - /* > - * Debugging requires use of the padding between object > - * and whatever may come after it. > - */ > - if (s->flags & (SLAB_RED_ZONE | SLAB_POISON)) > - return s->object_size; > -# endif > - if (s->flags & SLAB_KASAN) > - return s->object_size; > - /* > - * If we have the need to store the freelist pointer > - * back there or track user information then we can > - * only use the space before that information. > - */ > - if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER)) > - return s->inuse; > - /* > - * Else we can use all the padding etc for the allocation > - */ > - return s->size; > -#endif > } > > static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, > @@ -777,77 +418,18 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, > memcg_slab_post_alloc_hook(s, objcg, flags, size, p); > } > > -#ifndef CONFIG_SLOB > -/* > - * The slab lists for all objects. > - */ > -struct kmem_cache_node { > -#ifdef CONFIG_SLAB > - raw_spinlock_t list_lock; > - struct list_head slabs_partial; /* partial list first, better asm code */ > - struct list_head slabs_full; > - struct list_head slabs_free; > - unsigned long total_slabs; /* length of all slab lists */ > - unsigned long free_slabs; /* length of free slab list only */ > - unsigned long free_objects; > - unsigned int free_limit; > - unsigned int colour_next; /* Per-node cache coloring */ > - struct array_cache *shared; /* shared per node */ > - struct alien_cache **alien; /* on other nodes */ > - unsigned long next_reap; /* updated without locking */ > - int free_touched; /* updated without locking */ > -#endif > - > -#ifdef CONFIG_SLUB > - spinlock_t list_lock; > - unsigned long nr_partial; > - struct list_head partial; > -#ifdef CONFIG_SLUB_DEBUG > - atomic_long_t nr_slabs; > - atomic_long_t total_objects; > - struct list_head full; > -#endif > -#endif > - > -}; > - > -static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node) > -{ > - return s->node[node]; > -} > - > -/* > - * Iterator over all nodes. The body will be executed for each node that has > - * a kmem_cache_node structure allocated (which is true for all online nodes) > - */ > -#define for_each_kmem_cache_node(__s, __node, __n) \ > - for (__node = 0; __node < nr_node_ids; __node++) \ > - if ((__n = get_node(__s, __node))) > - > -#endif > - > -#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG) > -void dump_unreclaimable_slab(void); > -#else > static inline void dump_unreclaimable_slab(void) > { > } > -#endif > > void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr); > > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, > - gfp_t gfp); > -void cache_random_seq_destroy(struct kmem_cache *cachep); > -#else > static inline int cache_random_seq_create(struct kmem_cache *cachep, > unsigned int count, gfp_t gfp) > { > return 0; > } > static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { } > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > > static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c) > { > @@ -871,11 +453,7 @@ static inline bool slab_want_init_on_free(struct kmem_cache *c) > return false; > } > > -#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) > -void debugfs_slab_release(struct kmem_cache *); > -#else > static inline void debugfs_slab_release(struct kmem_cache *s) { } > -#endif > > #ifdef CONFIG_PRINTK > #define KS_ADDRS_COUNT 16 > @@ -903,8 +481,4 @@ void __check_heap_object(const void *ptr, unsigned long n, > } > #endif > > -#ifdef CONFIG_SLUB_DEBUG > -void skip_orig_size_check(struct kmem_cache *s, const void *object); > -#endif > - > #endif /* MM_SLAB_H */ > diff --git a/mm/slab_common.c b/mm/slab_common.c > index bf4e777cfe90..5f6a59e31abd 100644 > --- a/mm/slab_common.c > +++ b/mm/slab_common.c > @@ -69,11 +69,6 @@ static int __init setup_slab_merge(char *str) > return 1; > } > > -#ifdef CONFIG_SLUB > -__setup_param("slub_nomerge", slub_nomerge, setup_slab_nomerge, 0); > -__setup_param("slub_merge", slub_merge, setup_slab_merge, 0); > -#endif > - > __setup("slab_nomerge", setup_slab_nomerge); > __setup("slab_merge", setup_slab_merge); > > @@ -195,15 +190,29 @@ struct kmem_cache *find_mergeable(unsigned int size, unsigned int align, > if (s->size - size >= sizeof(void *)) > continue; > > - if (IS_ENABLED(CONFIG_SLAB) && align && > - (align > s->align || s->align % align)) > - continue; > - > return s; > } > return NULL; > } > > +struct slab_rcu { > + struct rcu_head head; > + int size; > +}; > + > +int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags) > +{ > + if (flags & SLAB_TYPESAFE_BY_RCU) { > + /* leave room for rcu footer at the end of object */ > + c->size += sizeof(struct slab_rcu); > + } > + > + /* Actual size allocated */ > + c->size = PAGE_SIZE << get_order(c->size); > + c->flags = flags; > + return 0; > +} > + > static struct kmem_cache *create_cache(const char *name, > unsigned int object_size, unsigned int align, > slab_flags_t flags, unsigned int useroffset, > @@ -285,20 +294,6 @@ kmem_cache_create_usercopy(const char *name, > const char *cache_name; > int err; > > -#ifdef CONFIG_SLUB_DEBUG > - /* > - * If no slub_debug was enabled globally, the static key is not yet > - * enabled by setup_slub_debug(). Enable it if the cache is being > - * created with any of the debugging flags passed explicitly. > - * It's also possible that this is the first cache created with > - * SLAB_STORE_USER and we should init stack_depot for it. > - */ > - if (flags & SLAB_DEBUG_FLAGS) > - static_branch_enable(&slub_debug_enabled); > - if (flags & SLAB_STORE_USER) > - stack_depot_init(); > -#endif > - > mutex_lock(&slab_mutex); > > err = kmem_cache_sanity_check(name, size); > @@ -552,7 +547,8 @@ static void kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab * > { > if (__kfence_obj_info(kpp, object, slab)) > return; > - __kmem_obj_info(kpp, object, slab); > + kpp->kp_ptr = object; > + kpp->kp_slab = slab; > } > > /** > @@ -625,462 +621,6 @@ void kmem_dump_obj(void *object) > EXPORT_SYMBOL_GPL(kmem_dump_obj); > #endif > > -#ifndef CONFIG_SLOB > -/* Create a cache during boot when no slab services are available yet */ > -void __init create_boot_cache(struct kmem_cache *s, const char *name, > - unsigned int size, slab_flags_t flags, > - unsigned int useroffset, unsigned int usersize) > -{ > - int err; > - unsigned int align = ARCH_KMALLOC_MINALIGN; > - > - s->name = name; > - s->size = s->object_size = size; > - > - /* > - * For power of two sizes, guarantee natural alignment for kmalloc > - * caches, regardless of SL*B debugging options. > - */ > - if (is_power_of_2(size)) > - align = max(align, size); > - s->align = calculate_alignment(flags, align, size); > - > -#ifdef CONFIG_HARDENED_USERCOPY > - s->useroffset = useroffset; > - s->usersize = usersize; > -#endif > - > - err = __kmem_cache_create(s, flags); > - > - if (err) > - panic("Creation of kmalloc slab %s size=%u failed. Reason %d\n", > - name, size, err); > - > - s->refcount = -1; /* Exempt from merging for now */ > -} > - > -struct kmem_cache *__init create_kmalloc_cache(const char *name, > - unsigned int size, slab_flags_t flags, > - unsigned int useroffset, unsigned int usersize) > -{ > - struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); > - > - if (!s) > - panic("Out of memory when creating slab %s\n", name); > - > - create_boot_cache(s, name, size, flags | SLAB_KMALLOC, useroffset, > - usersize); > - list_add(&s->list, &slab_caches); > - s->refcount = 1; > - return s; > -} > - > -struct kmem_cache * > -kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1] __ro_after_init = > -{ /* initialization for https://bugs.llvm.org/show_bug.cgi?id=42570 */ }; > -EXPORT_SYMBOL(kmalloc_caches); > - > -/* > - * Conversion table for small slabs sizes / 8 to the index in the > - * kmalloc array. This is necessary for slabs < 192 since we have non power > - * of two cache sizes there. The size of larger slabs can be determined using > - * fls. > - */ > -static u8 size_index[24] __ro_after_init = { > - 3, /* 8 */ > - 4, /* 16 */ > - 5, /* 24 */ > - 5, /* 32 */ > - 6, /* 40 */ > - 6, /* 48 */ > - 6, /* 56 */ > - 6, /* 64 */ > - 1, /* 72 */ > - 1, /* 80 */ > - 1, /* 88 */ > - 1, /* 96 */ > - 7, /* 104 */ > - 7, /* 112 */ > - 7, /* 120 */ > - 7, /* 128 */ > - 2, /* 136 */ > - 2, /* 144 */ > - 2, /* 152 */ > - 2, /* 160 */ > - 2, /* 168 */ > - 2, /* 176 */ > - 2, /* 184 */ > - 2 /* 192 */ > -}; > - > -static inline unsigned int size_index_elem(unsigned int bytes) > -{ > - return (bytes - 1) / 8; > -} > - > -/* > - * Find the kmem_cache structure that serves a given size of > - * allocation > - */ > -struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags) > -{ > - unsigned int index; > - > - if (size <= 192) { > - if (!size) > - return ZERO_SIZE_PTR; > - > - index = size_index[size_index_elem(size)]; > - } else { > - if (WARN_ON_ONCE(size > KMALLOC_MAX_CACHE_SIZE)) > - return NULL; > - index = fls(size - 1); > - } > - > - return kmalloc_caches[kmalloc_type(flags)][index]; > -} > - > -size_t kmalloc_size_roundup(size_t size) > -{ > - struct kmem_cache *c; > - > - /* Short-circuit the 0 size case. */ > - if (unlikely(size == 0)) > - return 0; > - /* Short-circuit saturated "too-large" case. */ > - if (unlikely(size == SIZE_MAX)) > - return SIZE_MAX; > - /* Above the smaller buckets, size is a multiple of page size. */ > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return PAGE_SIZE << get_order(size); > - > - /* The flags don't matter since size_index is common to all. */ > - c = kmalloc_slab(size, GFP_KERNEL); > - return c ? c->object_size : 0; > -} > -EXPORT_SYMBOL(kmalloc_size_roundup); > - > -#ifdef CONFIG_ZONE_DMA > -#define KMALLOC_DMA_NAME(sz) .name[KMALLOC_DMA] = "dma-kmalloc-" #sz, > -#else > -#define KMALLOC_DMA_NAME(sz) > -#endif > - > -#ifdef CONFIG_MEMCG_KMEM > -#define KMALLOC_CGROUP_NAME(sz) .name[KMALLOC_CGROUP] = "kmalloc-cg-" #sz, > -#else > -#define KMALLOC_CGROUP_NAME(sz) > -#endif > - > -#ifndef CONFIG_SLUB_TINY > -#define KMALLOC_RCL_NAME(sz) .name[KMALLOC_RECLAIM] = "kmalloc-rcl-" #sz, > -#else > -#define KMALLOC_RCL_NAME(sz) > -#endif > - > -#define INIT_KMALLOC_INFO(__size, __short_size) \ > -{ \ > - .name[KMALLOC_NORMAL] = "kmalloc-" #__short_size, \ > - KMALLOC_RCL_NAME(__short_size) \ > - KMALLOC_CGROUP_NAME(__short_size) \ > - KMALLOC_DMA_NAME(__short_size) \ > - .size = __size, \ > -} > - > -/* > - * kmalloc_info[] is to make slub_debug=,kmalloc-xx option work at boot time. > - * kmalloc_index() supports up to 2^21=2MB, so the final entry of the table is > - * kmalloc-2M. > - */ > -const struct kmalloc_info_struct kmalloc_info[] __initconst = { > - INIT_KMALLOC_INFO(0, 0), > - INIT_KMALLOC_INFO(96, 96), > - INIT_KMALLOC_INFO(192, 192), > - INIT_KMALLOC_INFO(8, 8), > - INIT_KMALLOC_INFO(16, 16), > - INIT_KMALLOC_INFO(32, 32), > - INIT_KMALLOC_INFO(64, 64), > - INIT_KMALLOC_INFO(128, 128), > - INIT_KMALLOC_INFO(256, 256), > - INIT_KMALLOC_INFO(512, 512), > - INIT_KMALLOC_INFO(1024, 1k), > - INIT_KMALLOC_INFO(2048, 2k), > - INIT_KMALLOC_INFO(4096, 4k), > - INIT_KMALLOC_INFO(8192, 8k), > - INIT_KMALLOC_INFO(16384, 16k), > - INIT_KMALLOC_INFO(32768, 32k), > - INIT_KMALLOC_INFO(65536, 64k), > - INIT_KMALLOC_INFO(131072, 128k), > - INIT_KMALLOC_INFO(262144, 256k), > - INIT_KMALLOC_INFO(524288, 512k), > - INIT_KMALLOC_INFO(1048576, 1M), > - INIT_KMALLOC_INFO(2097152, 2M) > -}; > - > -/* > - * Patch up the size_index table if we have strange large alignment > - * requirements for the kmalloc array. This is only the case for > - * MIPS it seems. The standard arches will not generate any code here. > - * > - * Largest permitted alignment is 256 bytes due to the way we > - * handle the index determination for the smaller caches. > - * > - * Make sure that nothing crazy happens if someone starts tinkering > - * around with ARCH_KMALLOC_MINALIGN > - */ > -void __init setup_kmalloc_cache_index_table(void) > -{ > - unsigned int i; > - > - BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 || > - !is_power_of_2(KMALLOC_MIN_SIZE)); > - > - for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) { > - unsigned int elem = size_index_elem(i); > - > - if (elem >= ARRAY_SIZE(size_index)) > - break; > - size_index[elem] = KMALLOC_SHIFT_LOW; > - } > - > - if (KMALLOC_MIN_SIZE >= 64) { > - /* > - * The 96 byte sized cache is not used if the alignment > - * is 64 byte. > - */ > - for (i = 64 + 8; i <= 96; i += 8) > - size_index[size_index_elem(i)] = 7; > - > - } > - > - if (KMALLOC_MIN_SIZE >= 128) { > - /* > - * The 192 byte sized cache is not used if the alignment > - * is 128 byte. Redirect kmalloc to use the 256 byte cache > - * instead. > - */ > - for (i = 128 + 8; i <= 192; i += 8) > - size_index[size_index_elem(i)] = 8; > - } > -} > - > -static void __init > -new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags) > -{ > - if ((KMALLOC_RECLAIM != KMALLOC_NORMAL) && (type == KMALLOC_RECLAIM)) { > - flags |= SLAB_RECLAIM_ACCOUNT; > - } else if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_CGROUP)) { > - if (mem_cgroup_kmem_disabled()) { > - kmalloc_caches[type][idx] = kmalloc_caches[KMALLOC_NORMAL][idx]; > - return; > - } > - flags |= SLAB_ACCOUNT; > - } else if (IS_ENABLED(CONFIG_ZONE_DMA) && (type == KMALLOC_DMA)) { > - flags |= SLAB_CACHE_DMA; > - } > - > - kmalloc_caches[type][idx] = create_kmalloc_cache( > - kmalloc_info[idx].name[type], > - kmalloc_info[idx].size, flags, 0, > - kmalloc_info[idx].size); > - > - /* > - * If CONFIG_MEMCG_KMEM is enabled, disable cache merging for > - * KMALLOC_NORMAL caches. > - */ > - if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_NORMAL)) > - kmalloc_caches[type][idx]->refcount = -1; > -} > - > -/* > - * Create the kmalloc array. Some of the regular kmalloc arrays > - * may already have been created because they were needed to > - * enable allocations for slab creation. > - */ > -void __init create_kmalloc_caches(slab_flags_t flags) > -{ > - int i; > - enum kmalloc_cache_type type; > - > - /* > - * Including KMALLOC_CGROUP if CONFIG_MEMCG_KMEM defined > - */ > - for (type = KMALLOC_NORMAL; type < NR_KMALLOC_TYPES; type++) { > - for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) { > - if (!kmalloc_caches[type][i]) > - new_kmalloc_cache(i, type, flags); > - > - /* > - * Caches that are not of the two-to-the-power-of size. > - * These have to be created immediately after the > - * earlier power of two caches > - */ > - if (KMALLOC_MIN_SIZE <= 32 && i == 6 && > - !kmalloc_caches[type][1]) > - new_kmalloc_cache(1, type, flags); > - if (KMALLOC_MIN_SIZE <= 64 && i == 7 && > - !kmalloc_caches[type][2]) > - new_kmalloc_cache(2, type, flags); > - } > - } > - > - /* Kmalloc array is now usable */ > - slab_state = UP; > -} > - > -void free_large_kmalloc(struct folio *folio, void *object) > -{ > - unsigned int order = folio_order(folio); > - > - if (WARN_ON_ONCE(order == 0)) > - pr_warn_once("object pointer: 0x%p\n", object); > - > - kmemleak_free(object); > - kasan_kfree_large(object); > - kmsan_kfree_large(object); > - > - mod_lruvec_page_state(folio_page(folio, 0), NR_SLAB_UNRECLAIMABLE_B, > - -(PAGE_SIZE << order)); > - __free_pages(folio_page(folio, 0), order); > -} > - > -static void *__kmalloc_large_node(size_t size, gfp_t flags, int node); > -static __always_inline > -void *__do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller) > -{ > - struct kmem_cache *s; > - void *ret; > - > - if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) { > - ret = __kmalloc_large_node(size, flags, node); > - trace_kmalloc(caller, ret, size, > - PAGE_SIZE << get_order(size), flags, node); > - return ret; > - } > - > - s = kmalloc_slab(size, flags); > - > - if (unlikely(ZERO_OR_NULL_PTR(s))) > - return s; > - > - ret = __kmem_cache_alloc_node(s, flags, node, size, caller); > - ret = kasan_kmalloc(s, ret, size, flags); > - trace_kmalloc(caller, ret, size, s->size, flags, node); > - return ret; > -} > - > -void *__kmalloc_node(size_t size, gfp_t flags, int node) > -{ > - return __do_kmalloc_node(size, flags, node, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc_node); > - > -void *__kmalloc(size_t size, gfp_t flags) > -{ > - return __do_kmalloc_node(size, flags, NUMA_NO_NODE, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc); > - > -void *__kmalloc_node_track_caller(size_t size, gfp_t flags, > - int node, unsigned long caller) > -{ > - return __do_kmalloc_node(size, flags, node, caller); > -} > -EXPORT_SYMBOL(__kmalloc_node_track_caller); > - > -/** > - * kfree - free previously allocated memory > - * @object: pointer returned by kmalloc. > - * > - * If @object is NULL, no operation is performed. > - * > - * Don't free memory not originally allocated by kmalloc() > - * or you will run into trouble. > - */ > -void kfree(const void *object) > -{ > - struct folio *folio; > - struct slab *slab; > - struct kmem_cache *s; > - > - trace_kfree(_RET_IP_, object); > - > - if (unlikely(ZERO_OR_NULL_PTR(object))) > - return; > - > - folio = virt_to_folio(object); > - if (unlikely(!folio_test_slab(folio))) { > - free_large_kmalloc(folio, (void *)object); > - return; > - } > - > - slab = folio_slab(folio); > - s = slab->slab_cache; > - __kmem_cache_free(s, (void *)object, _RET_IP_); > -} > -EXPORT_SYMBOL(kfree); > - > -/** > - * __ksize -- Report full size of underlying allocation > - * @object: pointer to the object > - * > - * This should only be used internally to query the true size of allocations. > - * It is not meant to be a way to discover the usable size of an allocation > - * after the fact. Instead, use kmalloc_size_roundup(). Using memory beyond > - * the originally requested allocation size may trigger KASAN, UBSAN_BOUNDS, > - * and/or FORTIFY_SOURCE. > - * > - * Return: size of the actual memory used by @object in bytes > - */ > -size_t __ksize(const void *object) > -{ > - struct folio *folio; > - > - if (unlikely(object == ZERO_SIZE_PTR)) > - return 0; > - > - folio = virt_to_folio(object); > - > - if (unlikely(!folio_test_slab(folio))) { > - if (WARN_ON(folio_size(folio) <= KMALLOC_MAX_CACHE_SIZE)) > - return 0; > - if (WARN_ON(object != folio_address(folio))) > - return 0; > - return folio_size(folio); > - } > - > -#ifdef CONFIG_SLUB_DEBUG > - skip_orig_size_check(folio_slab(folio)->slab_cache, object); > -#endif > - > - return slab_ksize(folio_slab(folio)->slab_cache); > -} > - > -void *kmalloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size) > -{ > - void *ret = __kmem_cache_alloc_node(s, gfpflags, NUMA_NO_NODE, > - size, _RET_IP_); > - > - trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags, NUMA_NO_NODE); > - > - ret = kasan_kmalloc(s, ret, size, gfpflags); > - return ret; > -} > -EXPORT_SYMBOL(kmalloc_trace); > - > -void *kmalloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, > - int node, size_t size) > -{ > - void *ret = __kmem_cache_alloc_node(s, gfpflags, node, size, _RET_IP_); > - > - trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags, node); > - > - ret = kasan_kmalloc(s, ret, size, gfpflags); > - return ret; > -} > -EXPORT_SYMBOL(kmalloc_node_trace); > -#endif /* !CONFIG_SLOB */ > - > gfp_t kmalloc_fix_flags(gfp_t flags) > { > gfp_t invalid_mask = flags & GFP_SLAB_BUG_MASK; > @@ -1144,202 +684,44 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) > } > EXPORT_SYMBOL(kmalloc_large_node); > > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -/* Randomize a generic freelist */ > -static void freelist_randomize(struct rnd_state *state, unsigned int *list, > - unsigned int count) > -{ > - unsigned int rand; > - unsigned int i; > - > - for (i = 0; i < count; i++) > - list[i] = i; > - > - /* Fisher-Yates shuffle */ > - for (i = count - 1; i > 0; i--) { > - rand = prandom_u32_state(state); > - rand %= (i + 1); > - swap(list[i], list[rand]); > - } > -} > - > -/* Create a random sequence per cache */ > -int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, > - gfp_t gfp) > -{ > - struct rnd_state state; > - > - if (count < 2 || cachep->random_seq) > - return 0; > - > - cachep->random_seq = kcalloc(count, sizeof(unsigned int), gfp); > - if (!cachep->random_seq) > - return -ENOMEM; > - > - /* Get best entropy at this stage of boot */ > - prandom_seed_state(&state, get_random_long()); > - > - freelist_randomize(&state, cachep->random_seq, count); > - return 0; > -} > - > -/* Destroy the per-cache random freelist sequence */ > -void cache_random_seq_destroy(struct kmem_cache *cachep) > -{ > - kfree(cachep->random_seq); > - cachep->random_seq = NULL; > -} > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > - > -#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG) > -#ifdef CONFIG_SLAB > -#define SLABINFO_RIGHTS (0600) > -#else > -#define SLABINFO_RIGHTS (0400) > -#endif > - > -static void print_slabinfo_header(struct seq_file *m) > -{ > - /* > - * Output format version, so at least we can change it > - * without _too_ many complaints. > - */ > -#ifdef CONFIG_DEBUG_SLAB > - seq_puts(m, "slabinfo - version: 2.1 (statistics)\n"); > -#else > - seq_puts(m, "slabinfo - version: 2.1\n"); > -#endif > - seq_puts(m, "# name <active_objs> <num_objs> <objsize> <objperslab> <pagesperslab>"); > - seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>"); > - seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>"); > -#ifdef CONFIG_DEBUG_SLAB > - seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> <error> <maxfreeable> <nodeallocs> <remotefrees> <alienoverflow>"); > - seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>"); > -#endif > - seq_putc(m, '\n'); > -} > - > -static void *slab_start(struct seq_file *m, loff_t *pos) > -{ > - mutex_lock(&slab_mutex); > - return seq_list_start(&slab_caches, *pos); > -} > - > -static void *slab_next(struct seq_file *m, void *p, loff_t *pos) > -{ > - return seq_list_next(p, &slab_caches, pos); > -} > - > -static void slab_stop(struct seq_file *m, void *p) > -{ > - mutex_unlock(&slab_mutex); > -} > - > -static void cache_show(struct kmem_cache *s, struct seq_file *m) > +static __always_inline void * > +__do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) > { > - struct slabinfo sinfo; > + void *ret; > > - memset(&sinfo, 0, sizeof(sinfo)); > - get_slabinfo(s, &sinfo); > + gfp &= gfp_allowed_mask; > > - seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", > - s->name, sinfo.active_objs, sinfo.num_objs, s->size, > - sinfo.objects_per_slab, (1 << sinfo.cache_order)); > + might_alloc(gfp); > > - seq_printf(m, " : tunables %4u %4u %4u", > - sinfo.limit, sinfo.batchcount, sinfo.shared); > - seq_printf(m, " : slabdata %6lu %6lu %6lu", > - sinfo.active_slabs, sinfo.num_slabs, sinfo.shared_avail); > - slabinfo_show_stats(m, s); > - seq_putc(m, '\n'); > -} > + if (unlikely(!size)) > + ret = ZERO_SIZE_PTR; > + else > + ret = __kmalloc_large_node(size, gfp, node); > > -static int slab_show(struct seq_file *m, void *p) > -{ > - struct kmem_cache *s = list_entry(p, struct kmem_cache, list); > + trace_kmalloc(caller, ret, size, PAGE_SIZE << get_order(size), gfp, node); > > - if (p == slab_caches.next) > - print_slabinfo_header(m); > - cache_show(s, m); > - return 0; > + kmemleak_alloc(ret, size, 1, gfp); > + return ret; > } > > -void dump_unreclaimable_slab(void) > +void *__kmalloc(size_t size, gfp_t gfp) > { > - struct kmem_cache *s; > - struct slabinfo sinfo; > - > - /* > - * Here acquiring slab_mutex is risky since we don't prefer to get > - * sleep in oom path. But, without mutex hold, it may introduce a > - * risk of crash. > - * Use mutex_trylock to protect the list traverse, dump nothing > - * without acquiring the mutex. > - */ > - if (!mutex_trylock(&slab_mutex)) { > - pr_warn("excessive unreclaimable slab but cannot dump stats\n"); > - return; > - } > - > - pr_info("Unreclaimable slab info:\n"); > - pr_info("Name Used Total\n"); > - > - list_for_each_entry(s, &slab_caches, list) { > - if (s->flags & SLAB_RECLAIM_ACCOUNT) > - continue; > - > - get_slabinfo(s, &sinfo); > - > - if (sinfo.num_objs > 0) > - pr_info("%-17s %10luKB %10luKB\n", s->name, > - (sinfo.active_objs * s->size) / 1024, > - (sinfo.num_objs * s->size) / 1024); > - } > - mutex_unlock(&slab_mutex); > + return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_); > } > +EXPORT_SYMBOL(__kmalloc); > > -/* > - * slabinfo_op - iterator that generates /proc/slabinfo > - * > - * Output layout: > - * cache-name > - * num-active-objs > - * total-objs > - * object size > - * num-active-slabs > - * total-slabs > - * num-pages-per-slab > - * + further values on SMP and with statistics enabled > - */ > -static const struct seq_operations slabinfo_op = { > - .start = slab_start, > - .next = slab_next, > - .stop = slab_stop, > - .show = slab_show, > -}; > - > -static int slabinfo_open(struct inode *inode, struct file *file) > +void *__kmalloc_node(size_t size, gfp_t gfp, int node) > { > - return seq_open(file, &slabinfo_op); > + return __do_kmalloc_node(size, gfp, node, _RET_IP_); > } > +EXPORT_SYMBOL(__kmalloc_node); > > -static const struct proc_ops slabinfo_proc_ops = { > - .proc_flags = PROC_ENTRY_PERMANENT, > - .proc_open = slabinfo_open, > - .proc_read = seq_read, > - .proc_write = slabinfo_write, > - .proc_lseek = seq_lseek, > - .proc_release = seq_release, > -}; > - > -static int __init slab_proc_init(void) > +void *__kmalloc_node_track_caller(size_t size, gfp_t gfp, > + int node, unsigned long caller) > { > - proc_create("slabinfo", SLABINFO_RIGHTS, NULL, &slabinfo_proc_ops); > - return 0; > + return __do_kmalloc_node(size, gfp, node, caller); > } > -module_init(slab_proc_init); > - > -#endif /* CONFIG_SLAB || CONFIG_SLUB_DEBUG */ > +EXPORT_SYMBOL(__kmalloc_node_track_caller); > > static __always_inline __realloc_size(2) void * > __do_krealloc(const void *p, size_t new_size, gfp_t flags) > @@ -1402,6 +784,27 @@ void *krealloc(const void *p, size_t new_size, gfp_t flags) > } > EXPORT_SYMBOL(krealloc); > > +void kfree(const void *block) > +{ > + struct folio *sp; > + unsigned int order; > + > + trace_kfree(_RET_IP_, block); > + > + if (unlikely(ZERO_OR_NULL_PTR(block))) > + return; > + kmemleak_free(block); > + > + sp = virt_to_folio(block); > + BUG_ON(folio_test_slab(sp)); > + order = folio_order(sp); > + > + mod_node_page_state(folio_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > + -(PAGE_SIZE << order)); > + __free_pages(folio_page(sp, 0), order); > +} > +EXPORT_SYMBOL(kfree); > + > /** > * kfree_sensitive - Clear sensitive information in memory before freeing > * @p: object to free memory of > @@ -1427,6 +830,34 @@ void kfree_sensitive(const void *p) > } > EXPORT_SYMBOL(kfree_sensitive); > > +size_t kmalloc_size_roundup(size_t size) > +{ > + /* Short-circuit the 0 size case. */ > + if (unlikely(size == 0)) > + return 0; > + /* Short-circuit saturated "too-large" case. */ > + if (unlikely(size == SIZE_MAX)) > + return SIZE_MAX; > + > + return PAGE_SIZE << get_order(size); > +} > + > +EXPORT_SYMBOL(kmalloc_size_roundup); > + > +/* can't use ksize for kmem_cache_alloc memory, only kmalloc */ > +size_t __ksize(const void *block) > +{ > + struct folio *folio; > + > + BUG_ON(!block); > + if (unlikely(block == ZERO_SIZE_PTR)) > + return 0; > + > + folio = virt_to_folio(block); > + BUG_ON(folio_test_slab(folio)); > + return folio_size(folio); > +} > + > size_t ksize(const void *objp) > { > /* > @@ -1451,6 +882,131 @@ size_t ksize(const void *objp) > } > EXPORT_SYMBOL(ksize); > > +static void *__kmem_cache_alloc_node(struct kmem_cache *c, gfp_t flags, int node) > +{ > + void *b; > + > + flags &= gfp_allowed_mask; > + > + might_alloc(flags); > + > + b = __kmalloc_large_node(c->size, flags, node); > + trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); > + > + if (b && c->ctor) { > + WARN_ON_ONCE(flags & __GFP_ZERO); > + c->ctor(b); > + } > + > + kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); > + return b; > +} > + > +void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) > +{ > + return __kmem_cache_alloc_node(cachep, flags, NUMA_NO_NODE); > +} > +EXPORT_SYMBOL(kmem_cache_alloc); > + > + > +void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags) > +{ > + return __kmem_cache_alloc_node(cachep, flags, NUMA_NO_NODE); > +} > +EXPORT_SYMBOL(kmem_cache_alloc_lru); > + > +void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node) > +{ > + return __kmem_cache_alloc_node(cachep, gfp, node); > +} > +EXPORT_SYMBOL(kmem_cache_alloc_node); > + > +static void kmem_rcu_free(struct rcu_head *head) > +{ > + struct slab_rcu *slab_rcu = (struct slab_rcu *)head; > + void *b = (void *)slab_rcu - (slab_rcu->size - sizeof(struct slab_rcu)); > + > + kfree(b); > +} > + > +void kmem_cache_free(struct kmem_cache *c, void *b) > +{ > + kmemleak_free_recursive(b, c->flags); > + trace_kmem_cache_free(_RET_IP_, b, c); > + if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) { > + struct slab_rcu *slab_rcu; > + slab_rcu = b + (c->size - sizeof(struct slab_rcu)); > + slab_rcu->size = c->size; > + call_rcu(&slab_rcu->head, kmem_rcu_free); > + } else { > + kfree(b); > + } > +} > +EXPORT_SYMBOL(kmem_cache_free); > + > +void kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p) > +{ > + size_t i; > + > + for (i = 0; i < nr; i++) { > + if (s) > + kmem_cache_free(s, p[i]); > + else > + kfree(p[i]); > + } > +} > +EXPORT_SYMBOL(kmem_cache_free_bulk); > + > +int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr, > + void **p) > +{ > + size_t i; > + > + for (i = 0; i < nr; i++) { > + void *x = p[i] = kmem_cache_alloc(s, flags); > + > + if (!x) { > + kmem_cache_free_bulk(s, i, p); > + return 0; > + } > + } > + return i; > +} > +EXPORT_SYMBOL(kmem_cache_alloc_bulk); > + > +int __kmem_cache_shutdown(struct kmem_cache *c) > +{ > + /* No way to check for remaining objects */ > + return 0; > +} > + > +void __kmem_cache_release(struct kmem_cache *c) > +{ > +} > + > +int __kmem_cache_shrink(struct kmem_cache *d) > +{ > + return 0; > +} > + > +static struct kmem_cache kmem_cache_boot = { > + .name = "kmem_cache", > + .size = sizeof(struct kmem_cache), > + .flags = SLAB_PANIC, > + .align = ARCH_KMALLOC_MINALIGN, > +}; > + > +void __init kmem_cache_init(void) > +{ > + kmem_cache = &kmem_cache_boot; > + slab_state = UP; > +} > + > +void __init kmem_cache_init_late(void) > +{ > + slab_state = FULL; > +} > + > /* Tracepoints definitions. */ > EXPORT_TRACEPOINT_SYMBOL(kmalloc); > EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc); > diff --git a/mm/slob.c b/mm/slob.c > deleted file mode 100644 > index fe567fcfa3a3..000000000000 > --- a/mm/slob.c > +++ /dev/null > @@ -1,757 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * SLOB Allocator: Simple List Of Blocks > - * > - * Matt Mackall <mpm@selenic.com> 12/30/03 > - * > - * NUMA support by Paul Mundt, 2007. > - * > - * How SLOB works: > - * > - * The core of SLOB is a traditional K&R style heap allocator, with > - * support for returning aligned objects. The granularity of this > - * allocator is as little as 2 bytes, however typically most architectures > - * will require 4 bytes on 32-bit and 8 bytes on 64-bit. > - * > - * The slob heap is a set of linked list of pages from alloc_pages(), > - * and within each page, there is a singly-linked list of free blocks > - * (slob_t). The heap is grown on demand. To reduce fragmentation, > - * heap pages are segregated into three lists, with objects less than > - * 256 bytes, objects less than 1024 bytes, and all other objects. > - * > - * Allocation from heap involves first searching for a page with > - * sufficient free blocks (using a next-fit-like approach) followed by > - * a first-fit scan of the page. Deallocation inserts objects back > - * into the free list in address order, so this is effectively an > - * address-ordered first fit. > - * > - * Above this is an implementation of kmalloc/kfree. Blocks returned > - * from kmalloc are prepended with a 4-byte header with the kmalloc size. > - * If kmalloc is asked for objects of PAGE_SIZE or larger, it calls > - * alloc_pages() directly, allocating compound pages so the page order > - * does not have to be separately tracked. > - * These objects are detected in kfree() because folio_test_slab() > - * is false for them. > - * > - * SLAB is emulated on top of SLOB by simply calling constructors and > - * destructors for every SLAB allocation. Objects are returned with the > - * 4-byte alignment unless the SLAB_HWCACHE_ALIGN flag is set, in which > - * case the low-level allocator will fragment blocks to create the proper > - * alignment. Again, objects of page-size or greater are allocated by > - * calling alloc_pages(). As SLAB objects know their size, no separate > - * size bookkeeping is necessary and there is essentially no allocation > - * space overhead, and compound pages aren't needed for multi-page > - * allocations. > - * > - * NUMA support in SLOB is fairly simplistic, pushing most of the real > - * logic down to the page allocator, and simply doing the node accounting > - * on the upper levels. In the event that a node id is explicitly > - * provided, __alloc_pages_node() with the specified node id is used > - * instead. The common case (or when the node id isn't explicitly provided) > - * will default to the current node, as per numa_node_id(). > - * > - * Node aware pages are still inserted in to the global freelist, and > - * these are scanned for by matching against the node id encoded in the > - * page flags. As a result, block allocations that can be satisfied from > - * the freelist will only be done so on pages residing on the same node, > - * in order to prevent random node placement. > - */ > - > -#include <linux/kernel.h> > -#include <linux/slab.h> > - > -#include <linux/mm.h> > -#include <linux/swap.h> /* struct reclaim_state */ > -#include <linux/cache.h> > -#include <linux/init.h> > -#include <linux/export.h> > -#include <linux/rcupdate.h> > -#include <linux/list.h> > -#include <linux/kmemleak.h> > - > -#include <trace/events/kmem.h> > - > -#include <linux/atomic.h> > - > -#include "slab.h" > -/* > - * slob_block has a field 'units', which indicates size of block if +ve, > - * or offset of next block if -ve (in SLOB_UNITs). > - * > - * Free blocks of size 1 unit simply contain the offset of the next block. > - * Those with larger size contain their size in the first SLOB_UNIT of > - * memory, and the offset of the next free block in the second SLOB_UNIT. > - */ > -#if PAGE_SIZE <= (32767 * 2) > -typedef s16 slobidx_t; > -#else > -typedef s32 slobidx_t; > -#endif > - > -struct slob_block { > - slobidx_t units; > -}; > -typedef struct slob_block slob_t; > - > -/* > - * All partially free slob pages go on these lists. > - */ > -#define SLOB_BREAK1 256 > -#define SLOB_BREAK2 1024 > -static LIST_HEAD(free_slob_small); > -static LIST_HEAD(free_slob_medium); > -static LIST_HEAD(free_slob_large); > - > -/* > - * slob_page_free: true for pages on free_slob_pages list. > - */ > -static inline int slob_page_free(struct slab *slab) > -{ > - return PageSlobFree(slab_page(slab)); > -} > - > -static void set_slob_page_free(struct slab *slab, struct list_head *list) > -{ > - list_add(&slab->slab_list, list); > - __SetPageSlobFree(slab_page(slab)); > -} > - > -static inline void clear_slob_page_free(struct slab *slab) > -{ > - list_del(&slab->slab_list); > - __ClearPageSlobFree(slab_page(slab)); > -} > - > -#define SLOB_UNIT sizeof(slob_t) > -#define SLOB_UNITS(size) DIV_ROUND_UP(size, SLOB_UNIT) > - > -/* > - * struct slob_rcu is inserted at the tail of allocated slob blocks, which > - * were created with a SLAB_TYPESAFE_BY_RCU slab. slob_rcu is used to free > - * the block using call_rcu. > - */ > -struct slob_rcu { > - struct rcu_head head; > - int size; > -}; > - > -/* > - * slob_lock protects all slob allocator structures. > - */ > -static DEFINE_SPINLOCK(slob_lock); > - > -/* > - * Encode the given size and next info into a free slob block s. > - */ > -static void set_slob(slob_t *s, slobidx_t size, slob_t *next) > -{ > - slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); > - slobidx_t offset = next - base; > - > - if (size > 1) { > - s[0].units = size; > - s[1].units = offset; > - } else > - s[0].units = -offset; > -} > - > -/* > - * Return the size of a slob block. > - */ > -static slobidx_t slob_units(slob_t *s) > -{ > - if (s->units > 0) > - return s->units; > - return 1; > -} > - > -/* > - * Return the next free slob block pointer after this one. > - */ > -static slob_t *slob_next(slob_t *s) > -{ > - slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); > - slobidx_t next; > - > - if (s[0].units < 0) > - next = -s[0].units; > - else > - next = s[1].units; > - return base+next; > -} > - > -/* > - * Returns true if s is the last free block in its page. > - */ > -static int slob_last(slob_t *s) > -{ > - return !((unsigned long)slob_next(s) & ~PAGE_MASK); > -} > - > -static void *slob_new_pages(gfp_t gfp, int order, int node) > -{ > - struct page *page; > - > -#ifdef CONFIG_NUMA > - if (node != NUMA_NO_NODE) > - page = __alloc_pages_node(node, gfp, order); > - else > -#endif > - page = alloc_pages(gfp, order); > - > - if (!page) > - return NULL; > - > - mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE_B, > - PAGE_SIZE << order); > - return page_address(page); > -} > - > -static void slob_free_pages(void *b, int order) > -{ > - struct page *sp = virt_to_page(b); > - > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += 1 << order; > - > - mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > - -(PAGE_SIZE << order)); > - __free_pages(sp, order); > -} > - > -/* > - * slob_page_alloc() - Allocate a slob block within a given slob_page sp. > - * @sp: Page to look in. > - * @size: Size of the allocation. > - * @align: Allocation alignment. > - * @align_offset: Offset in the allocated block that will be aligned. > - * @page_removed_from_list: Return parameter. > - * > - * Tries to find a chunk of memory at least @size bytes big within @page. > - * > - * Return: Pointer to memory if allocated, %NULL otherwise. If the > - * allocation fills up @page then the page is removed from the > - * freelist, in this case @page_removed_from_list will be set to > - * true (set to false otherwise). > - */ > -static void *slob_page_alloc(struct slab *sp, size_t size, int align, > - int align_offset, bool *page_removed_from_list) > -{ > - slob_t *prev, *cur, *aligned = NULL; > - int delta = 0, units = SLOB_UNITS(size); > - > - *page_removed_from_list = false; > - for (prev = NULL, cur = sp->freelist; ; prev = cur, cur = slob_next(cur)) { > - slobidx_t avail = slob_units(cur); > - > - /* > - * 'aligned' will hold the address of the slob block so that the > - * address 'aligned'+'align_offset' is aligned according to the > - * 'align' parameter. This is for kmalloc() which prepends the > - * allocated block with its size, so that the block itself is > - * aligned when needed. > - */ > - if (align) { > - aligned = (slob_t *) > - (ALIGN((unsigned long)cur + align_offset, align) > - - align_offset); > - delta = aligned - cur; > - } > - if (avail >= units + delta) { /* room enough? */ > - slob_t *next; > - > - if (delta) { /* need to fragment head to align? */ > - next = slob_next(cur); > - set_slob(aligned, avail - delta, next); > - set_slob(cur, delta, aligned); > - prev = cur; > - cur = aligned; > - avail = slob_units(cur); > - } > - > - next = slob_next(cur); > - if (avail == units) { /* exact fit? unlink. */ > - if (prev) > - set_slob(prev, slob_units(prev), next); > - else > - sp->freelist = next; > - } else { /* fragment */ > - if (prev) > - set_slob(prev, slob_units(prev), cur + units); > - else > - sp->freelist = cur + units; > - set_slob(cur + units, avail - units, next); > - } > - > - sp->units -= units; > - if (!sp->units) { > - clear_slob_page_free(sp); > - *page_removed_from_list = true; > - } > - return cur; > - } > - if (slob_last(cur)) > - return NULL; > - } > -} > - > -/* > - * slob_alloc: entry point into the slob allocator. > - */ > -static void *slob_alloc(size_t size, gfp_t gfp, int align, int node, > - int align_offset) > -{ > - struct folio *folio; > - struct slab *sp; > - struct list_head *slob_list; > - slob_t *b = NULL; > - unsigned long flags; > - bool _unused; > - > - if (size < SLOB_BREAK1) > - slob_list = &free_slob_small; > - else if (size < SLOB_BREAK2) > - slob_list = &free_slob_medium; > - else > - slob_list = &free_slob_large; > - > - spin_lock_irqsave(&slob_lock, flags); > - /* Iterate through each partially free page, try to find room */ > - list_for_each_entry(sp, slob_list, slab_list) { > - bool page_removed_from_list = false; > -#ifdef CONFIG_NUMA > - /* > - * If there's a node specification, search for a partial > - * page with a matching node id in the freelist. > - */ > - if (node != NUMA_NO_NODE && slab_nid(sp) != node) > - continue; > -#endif > - /* Enough room on this page? */ > - if (sp->units < SLOB_UNITS(size)) > - continue; > - > - b = slob_page_alloc(sp, size, align, align_offset, &page_removed_from_list); > - if (!b) > - continue; > - > - /* > - * If slob_page_alloc() removed sp from the list then we > - * cannot call list functions on sp. If so allocation > - * did not fragment the page anyway so optimisation is > - * unnecessary. > - */ > - if (!page_removed_from_list) { > - /* > - * Improve fragment distribution and reduce our average > - * search time by starting our next search here. (see > - * Knuth vol 1, sec 2.5, pg 449) > - */ > - if (!list_is_first(&sp->slab_list, slob_list)) > - list_rotate_to_front(&sp->slab_list, slob_list); > - } > - break; > - } > - spin_unlock_irqrestore(&slob_lock, flags); > - > - /* Not enough space: must allocate a new page */ > - if (!b) { > - b = slob_new_pages(gfp & ~__GFP_ZERO, 0, node); > - if (!b) > - return NULL; > - folio = virt_to_folio(b); > - __folio_set_slab(folio); > - sp = folio_slab(folio); > - > - spin_lock_irqsave(&slob_lock, flags); > - sp->units = SLOB_UNITS(PAGE_SIZE); > - sp->freelist = b; > - INIT_LIST_HEAD(&sp->slab_list); > - set_slob(b, SLOB_UNITS(PAGE_SIZE), b + SLOB_UNITS(PAGE_SIZE)); > - set_slob_page_free(sp, slob_list); > - b = slob_page_alloc(sp, size, align, align_offset, &_unused); > - BUG_ON(!b); > - spin_unlock_irqrestore(&slob_lock, flags); > - } > - if (unlikely(gfp & __GFP_ZERO)) > - memset(b, 0, size); > - return b; > -} > - > -/* > - * slob_free: entry point into the slob allocator. > - */ > -static void slob_free(void *block, int size) > -{ > - struct slab *sp; > - slob_t *prev, *next, *b = (slob_t *)block; > - slobidx_t units; > - unsigned long flags; > - struct list_head *slob_list; > - > - if (unlikely(ZERO_OR_NULL_PTR(block))) > - return; > - BUG_ON(!size); > - > - sp = virt_to_slab(block); > - units = SLOB_UNITS(size); > - > - spin_lock_irqsave(&slob_lock, flags); > - > - if (sp->units + units == SLOB_UNITS(PAGE_SIZE)) { > - /* Go directly to page allocator. Do not pass slob allocator */ > - if (slob_page_free(sp)) > - clear_slob_page_free(sp); > - spin_unlock_irqrestore(&slob_lock, flags); > - __folio_clear_slab(slab_folio(sp)); > - slob_free_pages(b, 0); > - return; > - } > - > - if (!slob_page_free(sp)) { > - /* This slob page is about to become partially free. Easy! */ > - sp->units = units; > - sp->freelist = b; > - set_slob(b, units, > - (void *)((unsigned long)(b + > - SLOB_UNITS(PAGE_SIZE)) & PAGE_MASK)); > - if (size < SLOB_BREAK1) > - slob_list = &free_slob_small; > - else if (size < SLOB_BREAK2) > - slob_list = &free_slob_medium; > - else > - slob_list = &free_slob_large; > - set_slob_page_free(sp, slob_list); > - goto out; > - } > - > - /* > - * Otherwise the page is already partially free, so find reinsertion > - * point. > - */ > - sp->units += units; > - > - if (b < (slob_t *)sp->freelist) { > - if (b + units == sp->freelist) { > - units += slob_units(sp->freelist); > - sp->freelist = slob_next(sp->freelist); > - } > - set_slob(b, units, sp->freelist); > - sp->freelist = b; > - } else { > - prev = sp->freelist; > - next = slob_next(prev); > - while (b > next) { > - prev = next; > - next = slob_next(prev); > - } > - > - if (!slob_last(prev) && b + units == next) { > - units += slob_units(next); > - set_slob(b, units, slob_next(next)); > - } else > - set_slob(b, units, next); > - > - if (prev + slob_units(prev) == b) { > - units = slob_units(b) + slob_units(prev); > - set_slob(prev, units, slob_next(b)); > - } else > - set_slob(prev, slob_units(prev), b); > - } > -out: > - spin_unlock_irqrestore(&slob_lock, flags); > -} > - > -#ifdef CONFIG_PRINTK > -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) > -{ > - kpp->kp_ptr = object; > - kpp->kp_slab = slab; > -} > -#endif > - > -/* > - * End of slob allocator proper. Begin kmem_cache_alloc and kmalloc frontend. > - */ > - > -static __always_inline void * > -__do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) > -{ > - unsigned int *m; > - unsigned int minalign; > - void *ret; > - > - minalign = max_t(unsigned int, ARCH_KMALLOC_MINALIGN, > - arch_slab_minalign()); > - gfp &= gfp_allowed_mask; > - > - might_alloc(gfp); > - > - if (size < PAGE_SIZE - minalign) { > - int align = minalign; > - > - /* > - * For power of two sizes, guarantee natural alignment for > - * kmalloc()'d objects. > - */ > - if (is_power_of_2(size)) > - align = max_t(unsigned int, minalign, size); > - > - if (!size) > - return ZERO_SIZE_PTR; > - > - m = slob_alloc(size + minalign, gfp, align, node, minalign); > - > - if (!m) > - return NULL; > - *m = size; > - ret = (void *)m + minalign; > - > - trace_kmalloc(caller, ret, size, size + minalign, gfp, node); > - } else { > - unsigned int order = get_order(size); > - > - if (likely(order)) > - gfp |= __GFP_COMP; > - ret = slob_new_pages(gfp, order, node); > - > - trace_kmalloc(caller, ret, size, PAGE_SIZE << order, gfp, node); > - } > - > - kmemleak_alloc(ret, size, 1, gfp); > - return ret; > -} > - > -void *__kmalloc(size_t size, gfp_t gfp) > -{ > - return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc); > - > -void *__kmalloc_node_track_caller(size_t size, gfp_t gfp, > - int node, unsigned long caller) > -{ > - return __do_kmalloc_node(size, gfp, node, caller); > -} > -EXPORT_SYMBOL(__kmalloc_node_track_caller); > - > -void kfree(const void *block) > -{ > - struct folio *sp; > - > - trace_kfree(_RET_IP_, block); > - > - if (unlikely(ZERO_OR_NULL_PTR(block))) > - return; > - kmemleak_free(block); > - > - sp = virt_to_folio(block); > - if (folio_test_slab(sp)) { > - unsigned int align = max_t(unsigned int, > - ARCH_KMALLOC_MINALIGN, > - arch_slab_minalign()); > - unsigned int *m = (unsigned int *)(block - align); > - > - slob_free(m, *m + align); > - } else { > - unsigned int order = folio_order(sp); > - > - mod_node_page_state(folio_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, > - -(PAGE_SIZE << order)); > - __free_pages(folio_page(sp, 0), order); > - > - } > -} > -EXPORT_SYMBOL(kfree); > - > -size_t kmalloc_size_roundup(size_t size) > -{ > - /* Short-circuit the 0 size case. */ > - if (unlikely(size == 0)) > - return 0; > - /* Short-circuit saturated "too-large" case. */ > - if (unlikely(size == SIZE_MAX)) > - return SIZE_MAX; > - > - return ALIGN(size, ARCH_KMALLOC_MINALIGN); > -} > - > -EXPORT_SYMBOL(kmalloc_size_roundup); > - > -/* can't use ksize for kmem_cache_alloc memory, only kmalloc */ > -size_t __ksize(const void *block) > -{ > - struct folio *folio; > - unsigned int align; > - unsigned int *m; > - > - BUG_ON(!block); > - if (unlikely(block == ZERO_SIZE_PTR)) > - return 0; > - > - folio = virt_to_folio(block); > - if (unlikely(!folio_test_slab(folio))) > - return folio_size(folio); > - > - align = max_t(unsigned int, ARCH_KMALLOC_MINALIGN, > - arch_slab_minalign()); > - m = (unsigned int *)(block - align); > - return SLOB_UNITS(*m) * SLOB_UNIT; > -} > - > -int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags) > -{ > - if (flags & SLAB_TYPESAFE_BY_RCU) { > - /* leave room for rcu footer at the end of object */ > - c->size += sizeof(struct slob_rcu); > - } > - > - /* Actual size allocated */ > - c->size = SLOB_UNITS(c->size) * SLOB_UNIT; > - c->flags = flags; > - return 0; > -} > - > -static void *slob_alloc_node(struct kmem_cache *c, gfp_t flags, int node) > -{ > - void *b; > - > - flags &= gfp_allowed_mask; > - > - might_alloc(flags); > - > - if (c->size < PAGE_SIZE) { > - b = slob_alloc(c->size, flags, c->align, node, 0); > - trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); > - } else { > - b = slob_new_pages(flags, get_order(c->size), node); > - trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); > - } > - > - if (b && c->ctor) { > - WARN_ON_ONCE(flags & __GFP_ZERO); > - c->ctor(b); > - } > - > - kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); > - return b; > -} > - > -void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) > -{ > - return slob_alloc_node(cachep, flags, NUMA_NO_NODE); > -} > -EXPORT_SYMBOL(kmem_cache_alloc); > - > - > -void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags) > -{ > - return slob_alloc_node(cachep, flags, NUMA_NO_NODE); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_lru); > - > -void *__kmalloc_node(size_t size, gfp_t gfp, int node) > -{ > - return __do_kmalloc_node(size, gfp, node, _RET_IP_); > -} > -EXPORT_SYMBOL(__kmalloc_node); > - > -void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node) > -{ > - return slob_alloc_node(cachep, gfp, node); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_node); > - > -static void __kmem_cache_free(void *b, int size) > -{ > - if (size < PAGE_SIZE) > - slob_free(b, size); > - else > - slob_free_pages(b, get_order(size)); > -} > - > -static void kmem_rcu_free(struct rcu_head *head) > -{ > - struct slob_rcu *slob_rcu = (struct slob_rcu *)head; > - void *b = (void *)slob_rcu - (slob_rcu->size - sizeof(struct slob_rcu)); > - > - __kmem_cache_free(b, slob_rcu->size); > -} > - > -void kmem_cache_free(struct kmem_cache *c, void *b) > -{ > - kmemleak_free_recursive(b, c->flags); > - trace_kmem_cache_free(_RET_IP_, b, c); > - if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) { > - struct slob_rcu *slob_rcu; > - slob_rcu = b + (c->size - sizeof(struct slob_rcu)); > - slob_rcu->size = c->size; > - call_rcu(&slob_rcu->head, kmem_rcu_free); > - } else { > - __kmem_cache_free(b, c->size); > - } > -} > -EXPORT_SYMBOL(kmem_cache_free); > - > -void kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p) > -{ > - size_t i; > - > - for (i = 0; i < nr; i++) { > - if (s) > - kmem_cache_free(s, p[i]); > - else > - kfree(p[i]); > - } > -} > -EXPORT_SYMBOL(kmem_cache_free_bulk); > - > -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr, > - void **p) > -{ > - size_t i; > - > - for (i = 0; i < nr; i++) { > - void *x = p[i] = kmem_cache_alloc(s, flags); > - > - if (!x) { > - kmem_cache_free_bulk(s, i, p); > - return 0; > - } > - } > - return i; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_bulk); > - > -int __kmem_cache_shutdown(struct kmem_cache *c) > -{ > - /* No way to check for remaining objects */ > - return 0; > -} > - > -void __kmem_cache_release(struct kmem_cache *c) > -{ > -} > - > -int __kmem_cache_shrink(struct kmem_cache *d) > -{ > - return 0; > -} > - > -static struct kmem_cache kmem_cache_boot = { > - .name = "kmem_cache", > - .size = sizeof(struct kmem_cache), > - .flags = SLAB_PANIC, > - .align = ARCH_KMALLOC_MINALIGN, > -}; > - > -void __init kmem_cache_init(void) > -{ > - kmem_cache = &kmem_cache_boot; > - slab_state = UP; > -} > - > -void __init kmem_cache_init_late(void) > -{ > - slab_state = FULL; > -} > diff --git a/mm/slub.c b/mm/slub.c > deleted file mode 100644 > index 39327e98fce3..000000000000 > --- a/mm/slub.c > +++ /dev/null > @@ -1,6506 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * SLUB: A slab allocator that limits cache line use instead of queuing > - * objects in per cpu and per node lists. > - * > - * The allocator synchronizes using per slab locks or atomic operations > - * and only uses a centralized lock to manage a pool of partial slabs. > - * > - * (C) 2007 SGI, Christoph Lameter > - * (C) 2011 Linux Foundation, Christoph Lameter > - */ > - > -#include <linux/mm.h> > -#include <linux/swap.h> /* struct reclaim_state */ > -#include <linux/module.h> > -#include <linux/bit_spinlock.h> > -#include <linux/interrupt.h> > -#include <linux/swab.h> > -#include <linux/bitops.h> > -#include <linux/slab.h> > -#include "slab.h" > -#include <linux/proc_fs.h> > -#include <linux/seq_file.h> > -#include <linux/kasan.h> > -#include <linux/kmsan.h> > -#include <linux/cpu.h> > -#include <linux/cpuset.h> > -#include <linux/mempolicy.h> > -#include <linux/ctype.h> > -#include <linux/stackdepot.h> > -#include <linux/debugobjects.h> > -#include <linux/kallsyms.h> > -#include <linux/kfence.h> > -#include <linux/memory.h> > -#include <linux/math64.h> > -#include <linux/fault-inject.h> > -#include <linux/stacktrace.h> > -#include <linux/prefetch.h> > -#include <linux/memcontrol.h> > -#include <linux/random.h> > -#include <kunit/test.h> > -#include <kunit/test-bug.h> > -#include <linux/sort.h> > - > -#include <linux/debugfs.h> > -#include <trace/events/kmem.h> > - > -#include "internal.h" > - > -/* > - * Lock order: > - * 1. slab_mutex (Global Mutex) > - * 2. node->list_lock (Spinlock) > - * 3. kmem_cache->cpu_slab->lock (Local lock) > - * 4. slab_lock(slab) (Only on some arches) > - * 5. object_map_lock (Only for debugging) > - * > - * slab_mutex > - * > - * The role of the slab_mutex is to protect the list of all the slabs > - * and to synchronize major metadata changes to slab cache structures. > - * Also synchronizes memory hotplug callbacks. > - * > - * slab_lock > - * > - * The slab_lock is a wrapper around the page lock, thus it is a bit > - * spinlock. > - * > - * The slab_lock is only used on arches that do not have the ability > - * to do a cmpxchg_double. It only protects: > - * > - * A. slab->freelist -> List of free objects in a slab > - * B. slab->inuse -> Number of objects in use > - * C. slab->objects -> Number of objects in slab > - * D. slab->frozen -> frozen state > - * > - * Frozen slabs > - * > - * If a slab is frozen then it is exempt from list management. It is not > - * on any list except per cpu partial list. The processor that froze the > - * slab is the one who can perform list operations on the slab. Other > - * processors may put objects onto the freelist but the processor that > - * froze the slab is the only one that can retrieve the objects from the > - * slab's freelist. > - * > - * list_lock > - * > - * The list_lock protects the partial and full list on each node and > - * the partial slab counter. If taken then no new slabs may be added or > - * removed from the lists nor make the number of partial slabs be modified. > - * (Note that the total number of slabs is an atomic value that may be > - * modified without taking the list lock). > - * > - * The list_lock is a centralized lock and thus we avoid taking it as > - * much as possible. As long as SLUB does not have to handle partial > - * slabs, operations can continue without any centralized lock. F.e. > - * allocating a long series of objects that fill up slabs does not require > - * the list lock. > - * > - * For debug caches, all allocations are forced to go through a list_lock > - * protected region to serialize against concurrent validation. > - * > - * cpu_slab->lock local lock > - * > - * This locks protect slowpath manipulation of all kmem_cache_cpu fields > - * except the stat counters. This is a percpu structure manipulated only by > - * the local cpu, so the lock protects against being preempted or interrupted > - * by an irq. Fast path operations rely on lockless operations instead. > - * > - * On PREEMPT_RT, the local lock neither disables interrupts nor preemption > - * which means the lockless fastpath cannot be used as it might interfere with > - * an in-progress slow path operations. In this case the local lock is always > - * taken but it still utilizes the freelist for the common operations. > - * > - * lockless fastpaths > - * > - * The fast path allocation (slab_alloc_node()) and freeing (do_slab_free()) > - * are fully lockless when satisfied from the percpu slab (and when > - * cmpxchg_double is possible to use, otherwise slab_lock is taken). > - * They also don't disable preemption or migration or irqs. They rely on > - * the transaction id (tid) field to detect being preempted or moved to > - * another cpu. > - * > - * irq, preemption, migration considerations > - * > - * Interrupts are disabled as part of list_lock or local_lock operations, or > - * around the slab_lock operation, in order to make the slab allocator safe > - * to use in the context of an irq. > - * > - * In addition, preemption (or migration on PREEMPT_RT) is disabled in the > - * allocation slowpath, bulk allocation, and put_cpu_partial(), so that the > - * local cpu doesn't change in the process and e.g. the kmem_cache_cpu pointer > - * doesn't have to be revalidated in each section protected by the local lock. > - * > - * SLUB assigns one slab for allocation to each processor. > - * Allocations only occur from these slabs called cpu slabs. > - * > - * Slabs with free elements are kept on a partial list and during regular > - * operations no list for full slabs is used. If an object in a full slab is > - * freed then the slab will show up again on the partial lists. > - * We track full slabs for debugging purposes though because otherwise we > - * cannot scan all objects. > - * > - * Slabs are freed when they become empty. Teardown and setup is > - * minimal so we rely on the page allocators per cpu caches for > - * fast frees and allocs. > - * > - * slab->frozen The slab is frozen and exempt from list processing. > - * This means that the slab is dedicated to a purpose > - * such as satisfying allocations for a specific > - * processor. Objects may be freed in the slab while > - * it is frozen but slab_free will then skip the usual > - * list operations. It is up to the processor holding > - * the slab to integrate the slab into the slab lists > - * when the slab is no longer needed. > - * > - * One use of this flag is to mark slabs that are > - * used for allocations. Then such a slab becomes a cpu > - * slab. The cpu slab may be equipped with an additional > - * freelist that allows lockless access to > - * free objects in addition to the regular freelist > - * that requires the slab lock. > - * > - * SLAB_DEBUG_FLAGS Slab requires special handling due to debug > - * options set. This moves slab handling out of > - * the fast path and disables lockless freelists. > - */ > - > -/* > - * We could simply use migrate_disable()/enable() but as long as it's a > - * function call even on !PREEMPT_RT, use inline preempt_disable() there. > - */ > -#ifndef CONFIG_PREEMPT_RT > -#define slub_get_cpu_ptr(var) get_cpu_ptr(var) > -#define slub_put_cpu_ptr(var) put_cpu_ptr(var) > -#define USE_LOCKLESS_FAST_PATH() (true) > -#else > -#define slub_get_cpu_ptr(var) \ > -({ \ > - migrate_disable(); \ > - this_cpu_ptr(var); \ > -}) > -#define slub_put_cpu_ptr(var) \ > -do { \ > - (void)(var); \ > - migrate_enable(); \ > -} while (0) > -#define USE_LOCKLESS_FAST_PATH() (false) > -#endif > - > -#ifndef CONFIG_SLUB_TINY > -#define __fastpath_inline __always_inline > -#else > -#define __fastpath_inline > -#endif > - > -#ifdef CONFIG_SLUB_DEBUG > -#ifdef CONFIG_SLUB_DEBUG_ON > -DEFINE_STATIC_KEY_TRUE(slub_debug_enabled); > -#else > -DEFINE_STATIC_KEY_FALSE(slub_debug_enabled); > -#endif > -#endif /* CONFIG_SLUB_DEBUG */ > - > -/* Structure holding parameters for get_partial() call chain */ > -struct partial_context { > - struct slab **slab; > - gfp_t flags; > - unsigned int orig_size; > -}; > - > -static inline bool kmem_cache_debug(struct kmem_cache *s) > -{ > - return kmem_cache_debug_flags(s, SLAB_DEBUG_FLAGS); > -} > - > -static inline bool slub_debug_orig_size(struct kmem_cache *s) > -{ > - return (kmem_cache_debug_flags(s, SLAB_STORE_USER) && > - (s->flags & SLAB_KMALLOC)); > -} > - > -void *fixup_red_left(struct kmem_cache *s, void *p) > -{ > - if (kmem_cache_debug_flags(s, SLAB_RED_ZONE)) > - p += s->red_left_pad; > - > - return p; > -} > - > -static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s) > -{ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - return !kmem_cache_debug(s); > -#else > - return false; > -#endif > -} > - > -/* > - * Issues still to be resolved: > - * > - * - Support PAGE_ALLOC_DEBUG. Should be easy to do. > - * > - * - Variable sizing of the per node arrays > - */ > - > -/* Enable to log cmpxchg failures */ > -#undef SLUB_DEBUG_CMPXCHG > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Minimum number of partial slabs. These will be left on the partial > - * lists even if they are empty. kmem_cache_shrink may reclaim them. > - */ > -#define MIN_PARTIAL 5 > - > -/* > - * Maximum number of desirable partial slabs. > - * The existence of more partial slabs makes kmem_cache_shrink > - * sort the partial list by the number of objects in use. > - */ > -#define MAX_PARTIAL 10 > -#else > -#define MIN_PARTIAL 0 > -#define MAX_PARTIAL 0 > -#endif > - > -#define DEBUG_DEFAULT_FLAGS (SLAB_CONSISTENCY_CHECKS | SLAB_RED_ZONE | \ > - SLAB_POISON | SLAB_STORE_USER) > - > -/* > - * These debug flags cannot use CMPXCHG because there might be consistency > - * issues when checking or reading debug information > - */ > -#define SLAB_NO_CMPXCHG (SLAB_CONSISTENCY_CHECKS | SLAB_STORE_USER | \ > - SLAB_TRACE) > - > - > -/* > - * Debugging flags that require metadata to be stored in the slab. These get > - * disabled when slub_debug=O is used and a cache's min order increases with > - * metadata. > - */ > -#define DEBUG_METADATA_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) > - > -#define OO_SHIFT 16 > -#define OO_MASK ((1 << OO_SHIFT) - 1) > -#define MAX_OBJS_PER_PAGE 32767 /* since slab.objects is u15 */ > - > -/* Internal SLUB flags */ > -/* Poison object */ > -#define __OBJECT_POISON ((slab_flags_t __force)0x80000000U) > -/* Use cmpxchg_double */ > -#define __CMPXCHG_DOUBLE ((slab_flags_t __force)0x40000000U) > - > -/* > - * Tracking user of a slab. > - */ > -#define TRACK_ADDRS_COUNT 16 > -struct track { > - unsigned long addr; /* Called from address */ > -#ifdef CONFIG_STACKDEPOT > - depot_stack_handle_t handle; > -#endif > - int cpu; /* Was running on cpu */ > - int pid; /* Pid context */ > - unsigned long when; /* When did the operation occur */ > -}; > - > -enum track_item { TRACK_ALLOC, TRACK_FREE }; > - > -#ifdef SLAB_SUPPORTS_SYSFS > -static int sysfs_slab_add(struct kmem_cache *); > -static int sysfs_slab_alias(struct kmem_cache *, const char *); > -#else > -static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; } > -static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) > - { return 0; } > -#endif > - > -#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) > -static void debugfs_slab_add(struct kmem_cache *); > -#else > -static inline void debugfs_slab_add(struct kmem_cache *s) { } > -#endif > - > -static inline void stat(const struct kmem_cache *s, enum stat_item si) > -{ > -#ifdef CONFIG_SLUB_STATS > - /* > - * The rmw is racy on a preemptible kernel but this is acceptable, so > - * avoid this_cpu_add()'s irq-disable overhead. > - */ > - raw_cpu_inc(s->cpu_slab->stat[si]); > -#endif > -} > - > -/* > - * Tracks for which NUMA nodes we have kmem_cache_nodes allocated. > - * Corresponds to node_state[N_NORMAL_MEMORY], but can temporarily > - * differ during memory hotplug/hotremove operations. > - * Protected by slab_mutex. > - */ > -static nodemask_t slab_nodes; > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Workqueue used for flush_cpu_slab(). > - */ > -static struct workqueue_struct *flushwq; > -#endif > - > -/******************************************************************** > - * Core slab cache functions > - *******************************************************************/ > - > -/* > - * Returns freelist pointer (ptr). With hardening, this is obfuscated > - * with an XOR of the address where the pointer is held and a per-cache > - * random number. > - */ > -static inline void *freelist_ptr(const struct kmem_cache *s, void *ptr, > - unsigned long ptr_addr) > -{ > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - /* > - * When CONFIG_KASAN_SW/HW_TAGS is enabled, ptr_addr might be tagged. > - * Normally, this doesn't cause any issues, as both set_freepointer() > - * and get_freepointer() are called with a pointer with the same tag. > - * However, there are some issues with CONFIG_SLUB_DEBUG code. For > - * example, when __free_slub() iterates over objects in a cache, it > - * passes untagged pointers to check_object(). check_object() in turns > - * calls get_freepointer() with an untagged pointer, which causes the > - * freepointer to be restored incorrectly. > - */ > - return (void *)((unsigned long)ptr ^ s->random ^ > - swab((unsigned long)kasan_reset_tag((void *)ptr_addr))); > -#else > - return ptr; > -#endif > -} > - > -/* Returns the freelist pointer recorded at location ptr_addr. */ > -static inline void *freelist_dereference(const struct kmem_cache *s, > - void *ptr_addr) > -{ > - return freelist_ptr(s, (void *)*(unsigned long *)(ptr_addr), > - (unsigned long)ptr_addr); > -} > - > -static inline void *get_freepointer(struct kmem_cache *s, void *object) > -{ > - object = kasan_reset_tag(object); > - return freelist_dereference(s, object + s->offset); > -} > - > -#ifndef CONFIG_SLUB_TINY > -static void prefetch_freepointer(const struct kmem_cache *s, void *object) > -{ > - prefetchw(object + s->offset); > -} > -#endif > - > -/* > - * When running under KMSAN, get_freepointer_safe() may return an uninitialized > - * pointer value in the case the current thread loses the race for the next > - * memory chunk in the freelist. In that case this_cpu_cmpxchg_double() in > - * slab_alloc_node() will fail, so the uninitialized value won't be used, but > - * KMSAN will still check all arguments of cmpxchg because of imperfect > - * handling of inline assembly. > - * To work around this problem, we apply __no_kmsan_checks to ensure that > - * get_freepointer_safe() returns initialized memory. > - */ > -__no_kmsan_checks > -static inline void *get_freepointer_safe(struct kmem_cache *s, void *object) > -{ > - unsigned long freepointer_addr; > - void *p; > - > - if (!debug_pagealloc_enabled_static()) > - return get_freepointer(s, object); > - > - object = kasan_reset_tag(object); > - freepointer_addr = (unsigned long)object + s->offset; > - copy_from_kernel_nofault(&p, (void **)freepointer_addr, sizeof(p)); > - return freelist_ptr(s, p, freepointer_addr); > -} > - > -static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) > -{ > - unsigned long freeptr_addr = (unsigned long)object + s->offset; > - > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - BUG_ON(object == fp); /* naive detection of double free or corruption */ > -#endif > - > - freeptr_addr = (unsigned long)kasan_reset_tag((void *)freeptr_addr); > - *(void **)freeptr_addr = freelist_ptr(s, fp, freeptr_addr); > -} > - > -/* Loop over all objects in a slab */ > -#define for_each_object(__p, __s, __addr, __objects) \ > - for (__p = fixup_red_left(__s, __addr); \ > - __p < (__addr) + (__objects) * (__s)->size; \ > - __p += (__s)->size) > - > -static inline unsigned int order_objects(unsigned int order, unsigned int size) > -{ > - return ((unsigned int)PAGE_SIZE << order) / size; > -} > - > -static inline struct kmem_cache_order_objects oo_make(unsigned int order, > - unsigned int size) > -{ > - struct kmem_cache_order_objects x = { > - (order << OO_SHIFT) + order_objects(order, size) > - }; > - > - return x; > -} > - > -static inline unsigned int oo_order(struct kmem_cache_order_objects x) > -{ > - return x.x >> OO_SHIFT; > -} > - > -static inline unsigned int oo_objects(struct kmem_cache_order_objects x) > -{ > - return x.x & OO_MASK; > -} > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -static void slub_set_cpu_partial(struct kmem_cache *s, unsigned int nr_objects) > -{ > - unsigned int nr_slabs; > - > - s->cpu_partial = nr_objects; > - > - /* > - * We take the number of objects but actually limit the number of > - * slabs on the per cpu partial list, in order to limit excessive > - * growth of the list. For simplicity we assume that the slabs will > - * be half-full. > - */ > - nr_slabs = DIV_ROUND_UP(nr_objects * 2, oo_objects(s->oo)); > - s->cpu_partial_slabs = nr_slabs; > -} > -#else > -static inline void > -slub_set_cpu_partial(struct kmem_cache *s, unsigned int nr_objects) > -{ > -} > -#endif /* CONFIG_SLUB_CPU_PARTIAL */ > - > -/* > - * Per slab locking using the pagelock > - */ > -static __always_inline void slab_lock(struct slab *slab) > -{ > - struct page *page = slab_page(slab); > - > - VM_BUG_ON_PAGE(PageTail(page), page); > - bit_spin_lock(PG_locked, &page->flags); > -} > - > -static __always_inline void slab_unlock(struct slab *slab) > -{ > - struct page *page = slab_page(slab); > - > - VM_BUG_ON_PAGE(PageTail(page), page); > - __bit_spin_unlock(PG_locked, &page->flags); > -} > - > -/* > - * Interrupts must be disabled (for the fallback code to work right), typically > - * by an _irqsave() lock variant. On PREEMPT_RT the preempt_disable(), which is > - * part of bit_spin_lock(), is sufficient because the policy is not to allow any > - * allocation/ free operation in hardirq context. Therefore nothing can > - * interrupt the operation. > - */ > -static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab, > - void *freelist_old, unsigned long counters_old, > - void *freelist_new, unsigned long counters_new, > - const char *n) > -{ > - if (USE_LOCKLESS_FAST_PATH()) > - lockdep_assert_irqs_disabled(); > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ > - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) > - if (s->flags & __CMPXCHG_DOUBLE) { > - if (cmpxchg_double(&slab->freelist, &slab->counters, > - freelist_old, counters_old, > - freelist_new, counters_new)) > - return true; > - } else > -#endif > - { > - slab_lock(slab); > - if (slab->freelist == freelist_old && > - slab->counters == counters_old) { > - slab->freelist = freelist_new; > - slab->counters = counters_new; > - slab_unlock(slab); > - return true; > - } > - slab_unlock(slab); > - } > - > - cpu_relax(); > - stat(s, CMPXCHG_DOUBLE_FAIL); > - > -#ifdef SLUB_DEBUG_CMPXCHG > - pr_info("%s %s: cmpxchg double redo ", n, s->name); > -#endif > - > - return false; > -} > - > -static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab, > - void *freelist_old, unsigned long counters_old, > - void *freelist_new, unsigned long counters_new, > - const char *n) > -{ > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ > - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) > - if (s->flags & __CMPXCHG_DOUBLE) { > - if (cmpxchg_double(&slab->freelist, &slab->counters, > - freelist_old, counters_old, > - freelist_new, counters_new)) > - return true; > - } else > -#endif > - { > - unsigned long flags; > - > - local_irq_save(flags); > - slab_lock(slab); > - if (slab->freelist == freelist_old && > - slab->counters == counters_old) { > - slab->freelist = freelist_new; > - slab->counters = counters_new; > - slab_unlock(slab); > - local_irq_restore(flags); > - return true; > - } > - slab_unlock(slab); > - local_irq_restore(flags); > - } > - > - cpu_relax(); > - stat(s, CMPXCHG_DOUBLE_FAIL); > - > -#ifdef SLUB_DEBUG_CMPXCHG > - pr_info("%s %s: cmpxchg double redo ", n, s->name); > -#endif > - > - return false; > -} > - > -#ifdef CONFIG_SLUB_DEBUG > -static unsigned long object_map[BITS_TO_LONGS(MAX_OBJS_PER_PAGE)]; > -static DEFINE_SPINLOCK(object_map_lock); > - > -static void __fill_map(unsigned long *obj_map, struct kmem_cache *s, > - struct slab *slab) > -{ > - void *addr = slab_address(slab); > - void *p; > - > - bitmap_zero(obj_map, slab->objects); > - > - for (p = slab->freelist; p; p = get_freepointer(s, p)) > - set_bit(__obj_to_index(s, addr, p), obj_map); > -} > - > -#if IS_ENABLED(CONFIG_KUNIT) > -static bool slab_add_kunit_errors(void) > -{ > - struct kunit_resource *resource; > - > - if (!kunit_get_current_test()) > - return false; > - > - resource = kunit_find_named_resource(current->kunit_test, "slab_errors"); > - if (!resource) > - return false; > - > - (*(int *)resource->data)++; > - kunit_put_resource(resource); > - return true; > -} > -#else > -static inline bool slab_add_kunit_errors(void) { return false; } > -#endif > - > -static inline unsigned int size_from_object(struct kmem_cache *s) > -{ > - if (s->flags & SLAB_RED_ZONE) > - return s->size - s->red_left_pad; > - > - return s->size; > -} > - > -static inline void *restore_red_left(struct kmem_cache *s, void *p) > -{ > - if (s->flags & SLAB_RED_ZONE) > - p -= s->red_left_pad; > - > - return p; > -} > - > -/* > - * Debug settings: > - */ > -#if defined(CONFIG_SLUB_DEBUG_ON) > -static slab_flags_t slub_debug = DEBUG_DEFAULT_FLAGS; > -#else > -static slab_flags_t slub_debug; > -#endif > - > -static char *slub_debug_string; > -static int disable_higher_order_debug; > - > -/* > - * slub is about to manipulate internal object metadata. This memory lies > - * outside the range of the allocated object, so accessing it would normally > - * be reported by kasan as a bounds error. metadata_access_enable() is used > - * to tell kasan that these accesses are OK. > - */ > -static inline void metadata_access_enable(void) > -{ > - kasan_disable_current(); > -} > - > -static inline void metadata_access_disable(void) > -{ > - kasan_enable_current(); > -} > - > -/* > - * Object debugging > - */ > - > -/* Verify that a pointer has an address that is valid within a slab page */ > -static inline int check_valid_pointer(struct kmem_cache *s, > - struct slab *slab, void *object) > -{ > - void *base; > - > - if (!object) > - return 1; > - > - base = slab_address(slab); > - object = kasan_reset_tag(object); > - object = restore_red_left(s, object); > - if (object < base || object >= base + slab->objects * s->size || > - (object - base) % s->size) { > - return 0; > - } > - > - return 1; > -} > - > -static void print_section(char *level, char *text, u8 *addr, > - unsigned int length) > -{ > - metadata_access_enable(); > - print_hex_dump(level, text, DUMP_PREFIX_ADDRESS, > - 16, 1, kasan_reset_tag((void *)addr), length, 1); > - metadata_access_disable(); > -} > - > -/* > - * See comment in calculate_sizes(). > - */ > -static inline bool freeptr_outside_object(struct kmem_cache *s) > -{ > - return s->offset >= s->inuse; > -} > - > -/* > - * Return offset of the end of info block which is inuse + free pointer if > - * not overlapping with object. > - */ > -static inline unsigned int get_info_end(struct kmem_cache *s) > -{ > - if (freeptr_outside_object(s)) > - return s->inuse + sizeof(void *); > - else > - return s->inuse; > -} > - > -static struct track *get_track(struct kmem_cache *s, void *object, > - enum track_item alloc) > -{ > - struct track *p; > - > - p = object + get_info_end(s); > - > - return kasan_reset_tag(p + alloc); > -} > - > -#ifdef CONFIG_STACKDEPOT > -static noinline depot_stack_handle_t set_track_prepare(void) > -{ > - depot_stack_handle_t handle; > - unsigned long entries[TRACK_ADDRS_COUNT]; > - unsigned int nr_entries; > - > - nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 3); > - handle = stack_depot_save(entries, nr_entries, GFP_NOWAIT); > - > - return handle; > -} > -#else > -static inline depot_stack_handle_t set_track_prepare(void) > -{ > - return 0; > -} > -#endif > - > -static void set_track_update(struct kmem_cache *s, void *object, > - enum track_item alloc, unsigned long addr, > - depot_stack_handle_t handle) > -{ > - struct track *p = get_track(s, object, alloc); > - > -#ifdef CONFIG_STACKDEPOT > - p->handle = handle; > -#endif > - p->addr = addr; > - p->cpu = smp_processor_id(); > - p->pid = current->pid; > - p->when = jiffies; > -} > - > -static __always_inline void set_track(struct kmem_cache *s, void *object, > - enum track_item alloc, unsigned long addr) > -{ > - depot_stack_handle_t handle = set_track_prepare(); > - > - set_track_update(s, object, alloc, addr, handle); > -} > - > -static void init_tracking(struct kmem_cache *s, void *object) > -{ > - struct track *p; > - > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - p = get_track(s, object, TRACK_ALLOC); > - memset(p, 0, 2*sizeof(struct track)); > -} > - > -static void print_track(const char *s, struct track *t, unsigned long pr_time) > -{ > - depot_stack_handle_t handle __maybe_unused; > - > - if (!t->addr) > - return; > - > - pr_err("%s in %pS age=%lu cpu=%u pid=%d\n", > - s, (void *)t->addr, pr_time - t->when, t->cpu, t->pid); > -#ifdef CONFIG_STACKDEPOT > - handle = READ_ONCE(t->handle); > - if (handle) > - stack_depot_print(handle); > - else > - pr_err("object allocation/free stack trace missing\n"); > -#endif > -} > - > -void print_tracking(struct kmem_cache *s, void *object) > -{ > - unsigned long pr_time = jiffies; > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - print_track("Allocated", get_track(s, object, TRACK_ALLOC), pr_time); > - print_track("Freed", get_track(s, object, TRACK_FREE), pr_time); > -} > - > -static void print_slab_info(const struct slab *slab) > -{ > - struct folio *folio = (struct folio *)slab_folio(slab); > - > - pr_err("Slab 0x%p objects=%u used=%u fp=0x%p flags=%pGp\n", > - slab, slab->objects, slab->inuse, slab->freelist, > - folio_flags(folio, 0)); > -} > - > -/* > - * kmalloc caches has fixed sizes (mostly power of 2), and kmalloc() API > - * family will round up the real request size to these fixed ones, so > - * there could be an extra area than what is requested. Save the original > - * request size in the meta data area, for better debug and sanity check. > - */ > -static inline void set_orig_size(struct kmem_cache *s, > - void *object, unsigned int orig_size) > -{ > - void *p = kasan_reset_tag(object); > - > - if (!slub_debug_orig_size(s)) > - return; > - > -#ifdef CONFIG_KASAN_GENERIC > - /* > - * KASAN could save its free meta data in object's data area at > - * offset 0, if the size is larger than 'orig_size', it will > - * overlap the data redzone in [orig_size+1, object_size], and > - * the check should be skipped. > - */ > - if (kasan_metadata_size(s, true) > orig_size) > - orig_size = s->object_size; > -#endif > - > - p += get_info_end(s); > - p += sizeof(struct track) * 2; > - > - *(unsigned int *)p = orig_size; > -} > - > -static inline unsigned int get_orig_size(struct kmem_cache *s, void *object) > -{ > - void *p = kasan_reset_tag(object); > - > - if (!slub_debug_orig_size(s)) > - return s->object_size; > - > - p += get_info_end(s); > - p += sizeof(struct track) * 2; > - > - return *(unsigned int *)p; > -} > - > -void skip_orig_size_check(struct kmem_cache *s, const void *object) > -{ > - set_orig_size(s, (void *)object, s->object_size); > -} > - > -static void slab_bug(struct kmem_cache *s, char *fmt, ...) > -{ > - struct va_format vaf; > - va_list args; > - > - va_start(args, fmt); > - vaf.fmt = fmt; > - vaf.va = &args; > - pr_err("=============================================================================\n"); > - pr_err("BUG %s (%s): %pV\n", s->name, print_tainted(), &vaf); > - pr_err("-----------------------------------------------------------------------------\n\n"); > - va_end(args); > -} > - > -__printf(2, 3) > -static void slab_fix(struct kmem_cache *s, char *fmt, ...) > -{ > - struct va_format vaf; > - va_list args; > - > - if (slab_add_kunit_errors()) > - return; > - > - va_start(args, fmt); > - vaf.fmt = fmt; > - vaf.va = &args; > - pr_err("FIX %s: %pV\n", s->name, &vaf); > - va_end(args); > -} > - > -static void print_trailer(struct kmem_cache *s, struct slab *slab, u8 *p) > -{ > - unsigned int off; /* Offset of last byte */ > - u8 *addr = slab_address(slab); > - > - print_tracking(s, p); > - > - print_slab_info(slab); > - > - pr_err("Object 0x%p @offset=%tu fp=0x%p\n\n", > - p, p - addr, get_freepointer(s, p)); > - > - if (s->flags & SLAB_RED_ZONE) > - print_section(KERN_ERR, "Redzone ", p - s->red_left_pad, > - s->red_left_pad); > - else if (p > addr + 16) > - print_section(KERN_ERR, "Bytes b4 ", p - 16, 16); > - > - print_section(KERN_ERR, "Object ", p, > - min_t(unsigned int, s->object_size, PAGE_SIZE)); > - if (s->flags & SLAB_RED_ZONE) > - print_section(KERN_ERR, "Redzone ", p + s->object_size, > - s->inuse - s->object_size); > - > - off = get_info_end(s); > - > - if (s->flags & SLAB_STORE_USER) > - off += 2 * sizeof(struct track); > - > - if (slub_debug_orig_size(s)) > - off += sizeof(unsigned int); > - > - off += kasan_metadata_size(s, false); > - > - if (off != size_from_object(s)) > - /* Beginning of the filler is the free pointer */ > - print_section(KERN_ERR, "Padding ", p + off, > - size_from_object(s) - off); > - > - dump_stack(); > -} > - > -static void object_err(struct kmem_cache *s, struct slab *slab, > - u8 *object, char *reason) > -{ > - if (slab_add_kunit_errors()) > - return; > - > - slab_bug(s, "%s", reason); > - print_trailer(s, slab, object); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > - > -static bool freelist_corrupted(struct kmem_cache *s, struct slab *slab, > - void **freelist, void *nextfree) > -{ > - if ((s->flags & SLAB_CONSISTENCY_CHECKS) && > - !check_valid_pointer(s, slab, nextfree) && freelist) { > - object_err(s, slab, *freelist, "Freechain corrupt"); > - *freelist = NULL; > - slab_fix(s, "Isolate corrupted freechain"); > - return true; > - } > - > - return false; > -} > - > -static __printf(3, 4) void slab_err(struct kmem_cache *s, struct slab *slab, > - const char *fmt, ...) > -{ > - va_list args; > - char buf[100]; > - > - if (slab_add_kunit_errors()) > - return; > - > - va_start(args, fmt); > - vsnprintf(buf, sizeof(buf), fmt, args); > - va_end(args); > - slab_bug(s, "%s", buf); > - print_slab_info(slab); > - dump_stack(); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > - > -static void init_object(struct kmem_cache *s, void *object, u8 val) > -{ > - u8 *p = kasan_reset_tag(object); > - unsigned int poison_size = s->object_size; > - > - if (s->flags & SLAB_RED_ZONE) { > - memset(p - s->red_left_pad, val, s->red_left_pad); > - > - if (slub_debug_orig_size(s) && val == SLUB_RED_ACTIVE) { > - /* > - * Redzone the extra allocated space by kmalloc than > - * requested, and the poison size will be limited to > - * the original request size accordingly. > - */ > - poison_size = get_orig_size(s, object); > - } > - } > - > - if (s->flags & __OBJECT_POISON) { > - memset(p, POISON_FREE, poison_size - 1); > - p[poison_size - 1] = POISON_END; > - } > - > - if (s->flags & SLAB_RED_ZONE) > - memset(p + poison_size, val, s->inuse - poison_size); > -} > - > -static void restore_bytes(struct kmem_cache *s, char *message, u8 data, > - void *from, void *to) > -{ > - slab_fix(s, "Restoring %s 0x%p-0x%p=0x%x", message, from, to - 1, data); > - memset(from, data, to - from); > -} > - > -static int check_bytes_and_report(struct kmem_cache *s, struct slab *slab, > - u8 *object, char *what, > - u8 *start, unsigned int value, unsigned int bytes) > -{ > - u8 *fault; > - u8 *end; > - u8 *addr = slab_address(slab); > - > - metadata_access_enable(); > - fault = memchr_inv(kasan_reset_tag(start), value, bytes); > - metadata_access_disable(); > - if (!fault) > - return 1; > - > - end = start + bytes; > - while (end > fault && end[-1] == value) > - end--; > - > - if (slab_add_kunit_errors()) > - goto skip_bug_print; > - > - slab_bug(s, "%s overwritten", what); > - pr_err("0x%p-0x%p @offset=%tu. First byte 0x%x instead of 0x%x\n", > - fault, end - 1, fault - addr, > - fault[0], value); > - print_trailer(s, slab, object); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > - > -skip_bug_print: > - restore_bytes(s, what, value, fault, end); > - return 0; > -} > - > -/* > - * Object layout: > - * > - * object address > - * Bytes of the object to be managed. > - * If the freepointer may overlay the object then the free > - * pointer is at the middle of the object. > - * > - * Poisoning uses 0x6b (POISON_FREE) and the last byte is > - * 0xa5 (POISON_END) > - * > - * object + s->object_size > - * Padding to reach word boundary. This is also used for Redzoning. > - * Padding is extended by another word if Redzoning is enabled and > - * object_size == inuse. > - * > - * We fill with 0xbb (RED_INACTIVE) for inactive objects and with > - * 0xcc (RED_ACTIVE) for objects in use. > - * > - * object + s->inuse > - * Meta data starts here. > - * > - * A. Free pointer (if we cannot overwrite object on free) > - * B. Tracking data for SLAB_STORE_USER > - * C. Original request size for kmalloc object (SLAB_STORE_USER enabled) > - * D. Padding to reach required alignment boundary or at minimum > - * one word if debugging is on to be able to detect writes > - * before the word boundary. > - * > - * Padding is done using 0x5a (POISON_INUSE) > - * > - * object + s->size > - * Nothing is used beyond s->size. > - * > - * If slabcaches are merged then the object_size and inuse boundaries are mostly > - * ignored. And therefore no slab options that rely on these boundaries > - * may be used with merged slabcaches. > - */ > - > -static int check_pad_bytes(struct kmem_cache *s, struct slab *slab, u8 *p) > -{ > - unsigned long off = get_info_end(s); /* The end of info */ > - > - if (s->flags & SLAB_STORE_USER) { > - /* We also have user information there */ > - off += 2 * sizeof(struct track); > - > - if (s->flags & SLAB_KMALLOC) > - off += sizeof(unsigned int); > - } > - > - off += kasan_metadata_size(s, false); > - > - if (size_from_object(s) == off) > - return 1; > - > - return check_bytes_and_report(s, slab, p, "Object padding", > - p + off, POISON_INUSE, size_from_object(s) - off); > -} > - > -/* Check the pad bytes at the end of a slab page */ > -static void slab_pad_check(struct kmem_cache *s, struct slab *slab) > -{ > - u8 *start; > - u8 *fault; > - u8 *end; > - u8 *pad; > - int length; > - int remainder; > - > - if (!(s->flags & SLAB_POISON)) > - return; > - > - start = slab_address(slab); > - length = slab_size(slab); > - end = start + length; > - remainder = length % s->size; > - if (!remainder) > - return; > - > - pad = end - remainder; > - metadata_access_enable(); > - fault = memchr_inv(kasan_reset_tag(pad), POISON_INUSE, remainder); > - metadata_access_disable(); > - if (!fault) > - return; > - while (end > fault && end[-1] == POISON_INUSE) > - end--; > - > - slab_err(s, slab, "Padding overwritten. 0x%p-0x%p @offset=%tu", > - fault, end - 1, fault - start); > - print_section(KERN_ERR, "Padding ", pad, remainder); > - > - restore_bytes(s, "slab padding", POISON_INUSE, fault, end); > -} > - > -static int check_object(struct kmem_cache *s, struct slab *slab, > - void *object, u8 val) > -{ > - u8 *p = object; > - u8 *endobject = object + s->object_size; > - unsigned int orig_size; > - > - if (s->flags & SLAB_RED_ZONE) { > - if (!check_bytes_and_report(s, slab, object, "Left Redzone", > - object - s->red_left_pad, val, s->red_left_pad)) > - return 0; > - > - if (!check_bytes_and_report(s, slab, object, "Right Redzone", > - endobject, val, s->inuse - s->object_size)) > - return 0; > - > - if (slub_debug_orig_size(s) && val == SLUB_RED_ACTIVE) { > - orig_size = get_orig_size(s, object); > - > - if (s->object_size > orig_size && > - !check_bytes_and_report(s, slab, object, > - "kmalloc Redzone", p + orig_size, > - val, s->object_size - orig_size)) { > - return 0; > - } > - } > - } else { > - if ((s->flags & SLAB_POISON) && s->object_size < s->inuse) { > - check_bytes_and_report(s, slab, p, "Alignment padding", > - endobject, POISON_INUSE, > - s->inuse - s->object_size); > - } > - } > - > - if (s->flags & SLAB_POISON) { > - if (val != SLUB_RED_ACTIVE && (s->flags & __OBJECT_POISON) && > - (!check_bytes_and_report(s, slab, p, "Poison", p, > - POISON_FREE, s->object_size - 1) || > - !check_bytes_and_report(s, slab, p, "End Poison", > - p + s->object_size - 1, POISON_END, 1))) > - return 0; > - /* > - * check_pad_bytes cleans up on its own. > - */ > - check_pad_bytes(s, slab, p); > - } > - > - if (!freeptr_outside_object(s) && val == SLUB_RED_ACTIVE) > - /* > - * Object and freepointer overlap. Cannot check > - * freepointer while object is allocated. > - */ > - return 1; > - > - /* Check free pointer validity */ > - if (!check_valid_pointer(s, slab, get_freepointer(s, p))) { > - object_err(s, slab, p, "Freepointer corrupt"); > - /* > - * No choice but to zap it and thus lose the remainder > - * of the free objects in this slab. May cause > - * another error because the object count is now wrong. > - */ > - set_freepointer(s, p, NULL); > - return 0; > - } > - return 1; > -} > - > -static int check_slab(struct kmem_cache *s, struct slab *slab) > -{ > - int maxobj; > - > - if (!folio_test_slab(slab_folio(slab))) { > - slab_err(s, slab, "Not a valid slab page"); > - return 0; > - } > - > - maxobj = order_objects(slab_order(slab), s->size); > - if (slab->objects > maxobj) { > - slab_err(s, slab, "objects %u > max %u", > - slab->objects, maxobj); > - return 0; > - } > - if (slab->inuse > slab->objects) { > - slab_err(s, slab, "inuse %u > max %u", > - slab->inuse, slab->objects); > - return 0; > - } > - /* Slab_pad_check fixes things up after itself */ > - slab_pad_check(s, slab); > - return 1; > -} > - > -/* > - * Determine if a certain object in a slab is on the freelist. Must hold the > - * slab lock to guarantee that the chains are in a consistent state. > - */ > -static int on_freelist(struct kmem_cache *s, struct slab *slab, void *search) > -{ > - int nr = 0; > - void *fp; > - void *object = NULL; > - int max_objects; > - > - fp = slab->freelist; > - while (fp && nr <= slab->objects) { > - if (fp == search) > - return 1; > - if (!check_valid_pointer(s, slab, fp)) { > - if (object) { > - object_err(s, slab, object, > - "Freechain corrupt"); > - set_freepointer(s, object, NULL); > - } else { > - slab_err(s, slab, "Freepointer corrupt"); > - slab->freelist = NULL; > - slab->inuse = slab->objects; > - slab_fix(s, "Freelist cleared"); > - return 0; > - } > - break; > - } > - object = fp; > - fp = get_freepointer(s, object); > - nr++; > - } > - > - max_objects = order_objects(slab_order(slab), s->size); > - if (max_objects > MAX_OBJS_PER_PAGE) > - max_objects = MAX_OBJS_PER_PAGE; > - > - if (slab->objects != max_objects) { > - slab_err(s, slab, "Wrong number of objects. Found %d but should be %d", > - slab->objects, max_objects); > - slab->objects = max_objects; > - slab_fix(s, "Number of objects adjusted"); > - } > - if (slab->inuse != slab->objects - nr) { > - slab_err(s, slab, "Wrong object count. Counter is %d but counted were %d", > - slab->inuse, slab->objects - nr); > - slab->inuse = slab->objects - nr; > - slab_fix(s, "Object count adjusted"); > - } > - return search == NULL; > -} > - > -static void trace(struct kmem_cache *s, struct slab *slab, void *object, > - int alloc) > -{ > - if (s->flags & SLAB_TRACE) { > - pr_info("TRACE %s %s 0x%p inuse=%d fp=0x%p\n", > - s->name, > - alloc ? "alloc" : "free", > - object, slab->inuse, > - slab->freelist); > - > - if (!alloc) > - print_section(KERN_INFO, "Object ", (void *)object, > - s->object_size); > - > - dump_stack(); > - } > -} > - > -/* > - * Tracking of fully allocated slabs for debugging purposes. > - */ > -static void add_full(struct kmem_cache *s, > - struct kmem_cache_node *n, struct slab *slab) > -{ > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - lockdep_assert_held(&n->list_lock); > - list_add(&slab->slab_list, &n->full); > -} > - > -static void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, struct slab *slab) > -{ > - if (!(s->flags & SLAB_STORE_USER)) > - return; > - > - lockdep_assert_held(&n->list_lock); > - list_del(&slab->slab_list); > -} > - > -/* Tracking of the number of slabs for debugging purposes */ > -static inline unsigned long slabs_node(struct kmem_cache *s, int node) > -{ > - struct kmem_cache_node *n = get_node(s, node); > - > - return atomic_long_read(&n->nr_slabs); > -} > - > -static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) > -{ > - return atomic_long_read(&n->nr_slabs); > -} > - > -static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects) > -{ > - struct kmem_cache_node *n = get_node(s, node); > - > - /* > - * May be called early in order to allocate a slab for the > - * kmem_cache_node structure. Solve the chicken-egg > - * dilemma by deferring the increment of the count during > - * bootstrap (see early_kmem_cache_node_alloc). > - */ > - if (likely(n)) { > - atomic_long_inc(&n->nr_slabs); > - atomic_long_add(objects, &n->total_objects); > - } > -} > -static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects) > -{ > - struct kmem_cache_node *n = get_node(s, node); > - > - atomic_long_dec(&n->nr_slabs); > - atomic_long_sub(objects, &n->total_objects); > -} > - > -/* Object debug checks for alloc/free paths */ > -static void setup_object_debug(struct kmem_cache *s, void *object) > -{ > - if (!kmem_cache_debug_flags(s, SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON)) > - return; > - > - init_object(s, object, SLUB_RED_INACTIVE); > - init_tracking(s, object); > -} > - > -static > -void setup_slab_debug(struct kmem_cache *s, struct slab *slab, void *addr) > -{ > - if (!kmem_cache_debug_flags(s, SLAB_POISON)) > - return; > - > - metadata_access_enable(); > - memset(kasan_reset_tag(addr), POISON_INUSE, slab_size(slab)); > - metadata_access_disable(); > -} > - > -static inline int alloc_consistency_checks(struct kmem_cache *s, > - struct slab *slab, void *object) > -{ > - if (!check_slab(s, slab)) > - return 0; > - > - if (!check_valid_pointer(s, slab, object)) { > - object_err(s, slab, object, "Freelist Pointer check fails"); > - return 0; > - } > - > - if (!check_object(s, slab, object, SLUB_RED_INACTIVE)) > - return 0; > - > - return 1; > -} > - > -static noinline bool alloc_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *object, int orig_size) > -{ > - if (s->flags & SLAB_CONSISTENCY_CHECKS) { > - if (!alloc_consistency_checks(s, slab, object)) > - goto bad; > - } > - > - /* Success. Perform special debug activities for allocs */ > - trace(s, slab, object, 1); > - set_orig_size(s, object, orig_size); > - init_object(s, object, SLUB_RED_ACTIVE); > - return true; > - > -bad: > - if (folio_test_slab(slab_folio(slab))) { > - /* > - * If this is a slab page then lets do the best we can > - * to avoid issues in the future. Marking all objects > - * as used avoids touching the remaining objects. > - */ > - slab_fix(s, "Marking all objects used"); > - slab->inuse = slab->objects; > - slab->freelist = NULL; > - } > - return false; > -} > - > -static inline int free_consistency_checks(struct kmem_cache *s, > - struct slab *slab, void *object, unsigned long addr) > -{ > - if (!check_valid_pointer(s, slab, object)) { > - slab_err(s, slab, "Invalid object pointer 0x%p", object); > - return 0; > - } > - > - if (on_freelist(s, slab, object)) { > - object_err(s, slab, object, "Object already free"); > - return 0; > - } > - > - if (!check_object(s, slab, object, SLUB_RED_ACTIVE)) > - return 0; > - > - if (unlikely(s != slab->slab_cache)) { > - if (!folio_test_slab(slab_folio(slab))) { > - slab_err(s, slab, "Attempt to free object(0x%p) outside of slab", > - object); > - } else if (!slab->slab_cache) { > - pr_err("SLUB <none>: no slab for object 0x%p.\n", > - object); > - dump_stack(); > - } else > - object_err(s, slab, object, > - "page slab pointer corrupt."); > - return 0; > - } > - return 1; > -} > - > -/* > - * Parse a block of slub_debug options. Blocks are delimited by ';' > - * > - * @str: start of block > - * @flags: returns parsed flags, or DEBUG_DEFAULT_FLAGS if none specified > - * @slabs: return start of list of slabs, or NULL when there's no list > - * @init: assume this is initial parsing and not per-kmem-create parsing > - * > - * returns the start of next block if there's any, or NULL > - */ > -static char * > -parse_slub_debug_flags(char *str, slab_flags_t *flags, char **slabs, bool init) > -{ > - bool higher_order_disable = false; > - > - /* Skip any completely empty blocks */ > - while (*str && *str == ';') > - str++; > - > - if (*str == ',') { > - /* > - * No options but restriction on slabs. This means full > - * debugging for slabs matching a pattern. > - */ > - *flags = DEBUG_DEFAULT_FLAGS; > - goto check_slabs; > - } > - *flags = 0; > - > - /* Determine which debug features should be switched on */ > - for (; *str && *str != ',' && *str != ';'; str++) { > - switch (tolower(*str)) { > - case '-': > - *flags = 0; > - break; > - case 'f': > - *flags |= SLAB_CONSISTENCY_CHECKS; > - break; > - case 'z': > - *flags |= SLAB_RED_ZONE; > - break; > - case 'p': > - *flags |= SLAB_POISON; > - break; > - case 'u': > - *flags |= SLAB_STORE_USER; > - break; > - case 't': > - *flags |= SLAB_TRACE; > - break; > - case 'a': > - *flags |= SLAB_FAILSLAB; > - break; > - case 'o': > - /* > - * Avoid enabling debugging on caches if its minimum > - * order would increase as a result. > - */ > - higher_order_disable = true; > - break; > - default: > - if (init) > - pr_err("slub_debug option '%c' unknown. skipped\n", *str); > - } > - } > -check_slabs: > - if (*str == ',') > - *slabs = ++str; > - else > - *slabs = NULL; > - > - /* Skip over the slab list */ > - while (*str && *str != ';') > - str++; > - > - /* Skip any completely empty blocks */ > - while (*str && *str == ';') > - str++; > - > - if (init && higher_order_disable) > - disable_higher_order_debug = 1; > - > - if (*str) > - return str; > - else > - return NULL; > -} > - > -static int __init setup_slub_debug(char *str) > -{ > - slab_flags_t flags; > - slab_flags_t global_flags; > - char *saved_str; > - char *slab_list; > - bool global_slub_debug_changed = false; > - bool slab_list_specified = false; > - > - global_flags = DEBUG_DEFAULT_FLAGS; > - if (*str++ != '=' || !*str) > - /* > - * No options specified. Switch on full debugging. > - */ > - goto out; > - > - saved_str = str; > - while (str) { > - str = parse_slub_debug_flags(str, &flags, &slab_list, true); > - > - if (!slab_list) { > - global_flags = flags; > - global_slub_debug_changed = true; > - } else { > - slab_list_specified = true; > - if (flags & SLAB_STORE_USER) > - stack_depot_request_early_init(); > - } > - } > - > - /* > - * For backwards compatibility, a single list of flags with list of > - * slabs means debugging is only changed for those slabs, so the global > - * slub_debug should be unchanged (0 or DEBUG_DEFAULT_FLAGS, depending > - * on CONFIG_SLUB_DEBUG_ON). We can extended that to multiple lists as > - * long as there is no option specifying flags without a slab list. > - */ > - if (slab_list_specified) { > - if (!global_slub_debug_changed) > - global_flags = slub_debug; > - slub_debug_string = saved_str; > - } > -out: > - slub_debug = global_flags; > - if (slub_debug & SLAB_STORE_USER) > - stack_depot_request_early_init(); > - if (slub_debug != 0 || slub_debug_string) > - static_branch_enable(&slub_debug_enabled); > - else > - static_branch_disable(&slub_debug_enabled); > - if ((static_branch_unlikely(&init_on_alloc) || > - static_branch_unlikely(&init_on_free)) && > - (slub_debug & SLAB_POISON)) > - pr_info("mem auto-init: SLAB_POISON will take precedence over init_on_alloc/init_on_free\n"); > - return 1; > -} > - > -__setup("slub_debug", setup_slub_debug); > - > -/* > - * kmem_cache_flags - apply debugging options to the cache > - * @object_size: the size of an object without meta data > - * @flags: flags to set > - * @name: name of the cache > - * > - * Debug option(s) are applied to @flags. In addition to the debug > - * option(s), if a slab name (or multiple) is specified i.e. > - * slub_debug=<Debug-Options>,<slab name1>,<slab name2> ... > - * then only the select slabs will receive the debug option(s). > - */ > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name) > -{ > - char *iter; > - size_t len; > - char *next_block; > - slab_flags_t block_flags; > - slab_flags_t slub_debug_local = slub_debug; > - > - if (flags & SLAB_NO_USER_FLAGS) > - return flags; > - > - /* > - * If the slab cache is for debugging (e.g. kmemleak) then > - * don't store user (stack trace) information by default, > - * but let the user enable it via the command line below. > - */ > - if (flags & SLAB_NOLEAKTRACE) > - slub_debug_local &= ~SLAB_STORE_USER; > - > - len = strlen(name); > - next_block = slub_debug_string; > - /* Go through all blocks of debug options, see if any matches our slab's name */ > - while (next_block) { > - next_block = parse_slub_debug_flags(next_block, &block_flags, &iter, false); > - if (!iter) > - continue; > - /* Found a block that has a slab list, search it */ > - while (*iter) { > - char *end, *glob; > - size_t cmplen; > - > - end = strchrnul(iter, ','); > - if (next_block && next_block < end) > - end = next_block - 1; > - > - glob = strnchr(iter, end - iter, '*'); > - if (glob) > - cmplen = glob - iter; > - else > - cmplen = max_t(size_t, len, (end - iter)); > - > - if (!strncmp(name, iter, cmplen)) { > - flags |= block_flags; > - return flags; > - } > - > - if (!*end || *end == ';') > - break; > - iter = end + 1; > - } > - } > - > - return flags | slub_debug_local; > -} > -#else /* !CONFIG_SLUB_DEBUG */ > -static inline void setup_object_debug(struct kmem_cache *s, void *object) {} > -static inline > -void setup_slab_debug(struct kmem_cache *s, struct slab *slab, void *addr) {} > - > -static inline bool alloc_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *object, int orig_size) { return true; } > - > -static inline bool free_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, int *bulk_cnt, > - unsigned long addr, depot_stack_handle_t handle) { return true; } > - > -static inline void slab_pad_check(struct kmem_cache *s, struct slab *slab) {} > -static inline int check_object(struct kmem_cache *s, struct slab *slab, > - void *object, u8 val) { return 1; } > -static inline depot_stack_handle_t set_track_prepare(void) { return 0; } > -static inline void set_track(struct kmem_cache *s, void *object, > - enum track_item alloc, unsigned long addr) {} > -static inline void add_full(struct kmem_cache *s, struct kmem_cache_node *n, > - struct slab *slab) {} > -static inline void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, > - struct slab *slab) {} > -slab_flags_t kmem_cache_flags(unsigned int object_size, > - slab_flags_t flags, const char *name) > -{ > - return flags; > -} > -#define slub_debug 0 > - > -#define disable_higher_order_debug 0 > - > -static inline unsigned long slabs_node(struct kmem_cache *s, int node) > - { return 0; } > -static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) > - { return 0; } > -static inline void inc_slabs_node(struct kmem_cache *s, int node, > - int objects) {} > -static inline void dec_slabs_node(struct kmem_cache *s, int node, > - int objects) {} > - > -#ifndef CONFIG_SLUB_TINY > -static bool freelist_corrupted(struct kmem_cache *s, struct slab *slab, > - void **freelist, void *nextfree) > -{ > - return false; > -} > -#endif > -#endif /* CONFIG_SLUB_DEBUG */ > - > -/* > - * Hooks for other subsystems that check memory allocations. In a typical > - * production configuration these hooks all should produce no code at all. > - */ > -static __always_inline bool slab_free_hook(struct kmem_cache *s, > - void *x, bool init) > -{ > - kmemleak_free_recursive(x, s->flags); > - kmsan_slab_free(s, x); > - > - debug_check_no_locks_freed(x, s->object_size); > - > - if (!(s->flags & SLAB_DEBUG_OBJECTS)) > - debug_check_no_obj_freed(x, s->object_size); > - > - /* Use KCSAN to help debug racy use-after-free. */ > - if (!(s->flags & SLAB_TYPESAFE_BY_RCU)) > - __kcsan_check_access(x, s->object_size, > - KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ASSERT); > - > - /* > - * As memory initialization might be integrated into KASAN, > - * kasan_slab_free and initialization memset's must be > - * kept together to avoid discrepancies in behavior. > - * > - * The initialization memset's clear the object and the metadata, > - * but don't touch the SLAB redzone. > - */ > - if (init) { > - int rsize; > - > - if (!kasan_has_integrated_init()) > - memset(kasan_reset_tag(x), 0, s->object_size); > - rsize = (s->flags & SLAB_RED_ZONE) ? s->red_left_pad : 0; > - memset((char *)kasan_reset_tag(x) + s->inuse, 0, > - s->size - s->inuse - rsize); > - } > - /* KASAN might put x into memory quarantine, delaying its reuse. */ > - return kasan_slab_free(s, x, init); > -} > - > -static inline bool slab_free_freelist_hook(struct kmem_cache *s, > - void **head, void **tail, > - int *cnt) > -{ > - > - void *object; > - void *next = *head; > - void *old_tail = *tail ? *tail : *head; > - > - if (is_kfence_address(next)) { > - slab_free_hook(s, next, false); > - return true; > - } > - > - /* Head and tail of the reconstructed freelist */ > - *head = NULL; > - *tail = NULL; > - > - do { > - object = next; > - next = get_freepointer(s, object); > - > - /* If object's reuse doesn't have to be delayed */ > - if (!slab_free_hook(s, object, slab_want_init_on_free(s))) { > - /* Move object to the new freelist */ > - set_freepointer(s, object, *head); > - *head = object; > - if (!*tail) > - *tail = object; > - } else { > - /* > - * Adjust the reconstructed freelist depth > - * accordingly if object's reuse is delayed. > - */ > - --(*cnt); > - } > - } while (object != old_tail); > - > - if (*head == *tail) > - *tail = NULL; > - > - return *head != NULL; > -} > - > -static void *setup_object(struct kmem_cache *s, void *object) > -{ > - setup_object_debug(s, object); > - object = kasan_init_slab_obj(s, object); > - if (unlikely(s->ctor)) { > - kasan_unpoison_object_data(s, object); > - s->ctor(object); > - kasan_poison_object_data(s, object); > - } > - return object; > -} > - > -/* > - * Slab allocation and freeing > - */ > -static inline struct slab *alloc_slab_page(gfp_t flags, int node, > - struct kmem_cache_order_objects oo) > -{ > - struct folio *folio; > - struct slab *slab; > - unsigned int order = oo_order(oo); > - > - if (node == NUMA_NO_NODE) > - folio = (struct folio *)alloc_pages(flags, order); > - else > - folio = (struct folio *)__alloc_pages_node(node, flags, order); > - > - if (!folio) > - return NULL; > - > - slab = folio_slab(folio); > - __folio_set_slab(folio); > - /* Make the flag visible before any changes to folio->mapping */ > - smp_wmb(); > - if (folio_is_pfmemalloc(folio)) > - slab_set_pfmemalloc(slab); > - > - return slab; > -} > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > -/* Pre-initialize the random sequence cache */ > -static int init_cache_random_seq(struct kmem_cache *s) > -{ > - unsigned int count = oo_objects(s->oo); > - int err; > - > - /* Bailout if already initialised */ > - if (s->random_seq) > - return 0; > - > - err = cache_random_seq_create(s, count, GFP_KERNEL); > - if (err) { > - pr_err("SLUB: Unable to initialize free list for %s\n", > - s->name); > - return err; > - } > - > - /* Transform to an offset on the set of pages */ > - if (s->random_seq) { > - unsigned int i; > - > - for (i = 0; i < count; i++) > - s->random_seq[i] *= s->size; > - } > - return 0; > -} > - > -/* Initialize each random sequence freelist per cache */ > -static void __init init_freelist_randomization(void) > -{ > - struct kmem_cache *s; > - > - mutex_lock(&slab_mutex); > - > - list_for_each_entry(s, &slab_caches, list) > - init_cache_random_seq(s); > - > - mutex_unlock(&slab_mutex); > -} > - > -/* Get the next entry on the pre-computed freelist randomized */ > -static void *next_freelist_entry(struct kmem_cache *s, struct slab *slab, > - unsigned long *pos, void *start, > - unsigned long page_limit, > - unsigned long freelist_count) > -{ > - unsigned int idx; > - > - /* > - * If the target page allocation failed, the number of objects on the > - * page might be smaller than the usual size defined by the cache. > - */ > - do { > - idx = s->random_seq[*pos]; > - *pos += 1; > - if (*pos >= freelist_count) > - *pos = 0; > - } while (unlikely(idx >= page_limit)); > - > - return (char *)start + idx; > -} > - > -/* Shuffle the single linked freelist based on a random pre-computed sequence */ > -static bool shuffle_freelist(struct kmem_cache *s, struct slab *slab) > -{ > - void *start; > - void *cur; > - void *next; > - unsigned long idx, pos, page_limit, freelist_count; > - > - if (slab->objects < 2 || !s->random_seq) > - return false; > - > - freelist_count = oo_objects(s->oo); > - pos = get_random_u32_below(freelist_count); > - > - page_limit = slab->objects * s->size; > - start = fixup_red_left(s, slab_address(slab)); > - > - /* First entry is used as the base of the freelist */ > - cur = next_freelist_entry(s, slab, &pos, start, page_limit, > - freelist_count); > - cur = setup_object(s, cur); > - slab->freelist = cur; > - > - for (idx = 1; idx < slab->objects; idx++) { > - next = next_freelist_entry(s, slab, &pos, start, page_limit, > - freelist_count); > - next = setup_object(s, next); > - set_freepointer(s, cur, next); > - cur = next; > - } > - set_freepointer(s, cur, NULL); > - > - return true; > -} > -#else > -static inline int init_cache_random_seq(struct kmem_cache *s) > -{ > - return 0; > -} > -static inline void init_freelist_randomization(void) { } > -static inline bool shuffle_freelist(struct kmem_cache *s, struct slab *slab) > -{ > - return false; > -} > -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ > - > -static struct slab *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) > -{ > - struct slab *slab; > - struct kmem_cache_order_objects oo = s->oo; > - gfp_t alloc_gfp; > - void *start, *p, *next; > - int idx; > - bool shuffle; > - > - flags &= gfp_allowed_mask; > - > - flags |= s->allocflags; > - > - /* > - * Let the initial higher-order allocation fail under memory pressure > - * so we fall-back to the minimum order allocation. > - */ > - alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL; > - if ((alloc_gfp & __GFP_DIRECT_RECLAIM) && oo_order(oo) > oo_order(s->min)) > - alloc_gfp = (alloc_gfp | __GFP_NOMEMALLOC) & ~__GFP_RECLAIM; > - > - slab = alloc_slab_page(alloc_gfp, node, oo); > - if (unlikely(!slab)) { > - oo = s->min; > - alloc_gfp = flags; > - /* > - * Allocation may have failed due to fragmentation. > - * Try a lower order alloc if possible > - */ > - slab = alloc_slab_page(alloc_gfp, node, oo); > - if (unlikely(!slab)) > - return NULL; > - stat(s, ORDER_FALLBACK); > - } > - > - slab->objects = oo_objects(oo); > - slab->inuse = 0; > - slab->frozen = 0; > - > - account_slab(slab, oo_order(oo), s, flags); > - > - slab->slab_cache = s; > - > - kasan_poison_slab(slab); > - > - start = slab_address(slab); > - > - setup_slab_debug(s, slab, start); > - > - shuffle = shuffle_freelist(s, slab); > - > - if (!shuffle) { > - start = fixup_red_left(s, start); > - start = setup_object(s, start); > - slab->freelist = start; > - for (idx = 0, p = start; idx < slab->objects - 1; idx++) { > - next = p + s->size; > - next = setup_object(s, next); > - set_freepointer(s, p, next); > - p = next; > - } > - set_freepointer(s, p, NULL); > - } > - > - return slab; > -} > - > -static struct slab *new_slab(struct kmem_cache *s, gfp_t flags, int node) > -{ > - if (unlikely(flags & GFP_SLAB_BUG_MASK)) > - flags = kmalloc_fix_flags(flags); > - > - WARN_ON_ONCE(s->ctor && (flags & __GFP_ZERO)); > - > - return allocate_slab(s, > - flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node); > -} > - > -static void __free_slab(struct kmem_cache *s, struct slab *slab) > -{ > - struct folio *folio = slab_folio(slab); > - int order = folio_order(folio); > - int pages = 1 << order; > - > - __slab_clear_pfmemalloc(slab); > - folio->mapping = NULL; > - /* Make the mapping reset visible before clearing the flag */ > - smp_wmb(); > - __folio_clear_slab(folio); > - if (current->reclaim_state) > - current->reclaim_state->reclaimed_slab += pages; > - unaccount_slab(slab, order, s); > - __free_pages(&folio->page, order); > -} > - > -static void rcu_free_slab(struct rcu_head *h) > -{ > - struct slab *slab = container_of(h, struct slab, rcu_head); > - > - __free_slab(slab->slab_cache, slab); > -} > - > -static void free_slab(struct kmem_cache *s, struct slab *slab) > -{ > - if (kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) { > - void *p; > - > - slab_pad_check(s, slab); > - for_each_object(p, s, slab_address(slab), slab->objects) > - check_object(s, slab, p, SLUB_RED_INACTIVE); > - } > - > - if (unlikely(s->flags & SLAB_TYPESAFE_BY_RCU)) > - call_rcu(&slab->rcu_head, rcu_free_slab); > - else > - __free_slab(s, slab); > -} > - > -static void discard_slab(struct kmem_cache *s, struct slab *slab) > -{ > - dec_slabs_node(s, slab_nid(slab), slab->objects); > - free_slab(s, slab); > -} > - > -/* > - * Management of partially allocated slabs. > - */ > -static inline void > -__add_partial(struct kmem_cache_node *n, struct slab *slab, int tail) > -{ > - n->nr_partial++; > - if (tail == DEACTIVATE_TO_TAIL) > - list_add_tail(&slab->slab_list, &n->partial); > - else > - list_add(&slab->slab_list, &n->partial); > -} > - > -static inline void add_partial(struct kmem_cache_node *n, > - struct slab *slab, int tail) > -{ > - lockdep_assert_held(&n->list_lock); > - __add_partial(n, slab, tail); > -} > - > -static inline void remove_partial(struct kmem_cache_node *n, > - struct slab *slab) > -{ > - lockdep_assert_held(&n->list_lock); > - list_del(&slab->slab_list); > - n->nr_partial--; > -} > - > -/* > - * Called only for kmem_cache_debug() caches instead of acquire_slab(), with a > - * slab from the n->partial list. Remove only a single object from the slab, do > - * the alloc_debug_processing() checks and leave the slab on the list, or move > - * it to full list if it was the last free object. > - */ > -static void *alloc_single_from_partial(struct kmem_cache *s, > - struct kmem_cache_node *n, struct slab *slab, int orig_size) > -{ > - void *object; > - > - lockdep_assert_held(&n->list_lock); > - > - object = slab->freelist; > - slab->freelist = get_freepointer(s, object); > - slab->inuse++; > - > - if (!alloc_debug_processing(s, slab, object, orig_size)) { > - remove_partial(n, slab); > - return NULL; > - } > - > - if (slab->inuse == slab->objects) { > - remove_partial(n, slab); > - add_full(s, n, slab); > - } > - > - return object; > -} > - > -/* > - * Called only for kmem_cache_debug() caches to allocate from a freshly > - * allocated slab. Allocate a single object instead of whole freelist > - * and put the slab to the partial (or full) list. > - */ > -static void *alloc_single_from_new_slab(struct kmem_cache *s, > - struct slab *slab, int orig_size) > -{ > - int nid = slab_nid(slab); > - struct kmem_cache_node *n = get_node(s, nid); > - unsigned long flags; > - void *object; > - > - > - object = slab->freelist; > - slab->freelist = get_freepointer(s, object); > - slab->inuse = 1; > - > - if (!alloc_debug_processing(s, slab, object, orig_size)) > - /* > - * It's not really expected that this would fail on a > - * freshly allocated slab, but a concurrent memory > - * corruption in theory could cause that. > - */ > - return NULL; > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - if (slab->inuse == slab->objects) > - add_full(s, n, slab); > - else > - add_partial(n, slab, DEACTIVATE_TO_HEAD); > - > - inc_slabs_node(s, nid, slab->objects); > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - return object; > -} > - > -/* > - * Remove slab from the partial list, freeze it and > - * return the pointer to the freelist. > - * > - * Returns a list of objects or NULL if it fails. > - */ > -static inline void *acquire_slab(struct kmem_cache *s, > - struct kmem_cache_node *n, struct slab *slab, > - int mode) > -{ > - void *freelist; > - unsigned long counters; > - struct slab new; > - > - lockdep_assert_held(&n->list_lock); > - > - /* > - * Zap the freelist and set the frozen bit. > - * The old freelist is the list of objects for the > - * per cpu allocation list. > - */ > - freelist = slab->freelist; > - counters = slab->counters; > - new.counters = counters; > - if (mode) { > - new.inuse = slab->objects; > - new.freelist = NULL; > - } else { > - new.freelist = freelist; > - } > - > - VM_BUG_ON(new.frozen); > - new.frozen = 1; > - > - if (!__cmpxchg_double_slab(s, slab, > - freelist, counters, > - new.freelist, new.counters, > - "acquire_slab")) > - return NULL; > - > - remove_partial(n, slab); > - WARN_ON(!freelist); > - return freelist; > -} > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -static void put_cpu_partial(struct kmem_cache *s, struct slab *slab, int drain); > -#else > -static inline void put_cpu_partial(struct kmem_cache *s, struct slab *slab, > - int drain) { } > -#endif > -static inline bool pfmemalloc_match(struct slab *slab, gfp_t gfpflags); > - > -/* > - * Try to allocate a partial slab from a specific node. > - */ > -static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n, > - struct partial_context *pc) > -{ > - struct slab *slab, *slab2; > - void *object = NULL; > - unsigned long flags; > - unsigned int partial_slabs = 0; > - > - /* > - * Racy check. If we mistakenly see no partial slabs then we > - * just allocate an empty slab. If we mistakenly try to get a > - * partial slab and there is none available then get_partial() > - * will return NULL. > - */ > - if (!n || !n->nr_partial) > - return NULL; > - > - spin_lock_irqsave(&n->list_lock, flags); > - list_for_each_entry_safe(slab, slab2, &n->partial, slab_list) { > - void *t; > - > - if (!pfmemalloc_match(slab, pc->flags)) > - continue; > - > - if (IS_ENABLED(CONFIG_SLUB_TINY) || kmem_cache_debug(s)) { > - object = alloc_single_from_partial(s, n, slab, > - pc->orig_size); > - if (object) > - break; > - continue; > - } > - > - t = acquire_slab(s, n, slab, object == NULL); > - if (!t) > - break; > - > - if (!object) { > - *pc->slab = slab; > - stat(s, ALLOC_FROM_PARTIAL); > - object = t; > - } else { > - put_cpu_partial(s, slab, 0); > - stat(s, CPU_PARTIAL_NODE); > - partial_slabs++; > - } > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - if (!kmem_cache_has_cpu_partial(s) > - || partial_slabs > s->cpu_partial_slabs / 2) > - break; > -#else > - break; > -#endif > - > - } > - spin_unlock_irqrestore(&n->list_lock, flags); > - return object; > -} > - > -/* > - * Get a slab from somewhere. Search in increasing NUMA distances. > - */ > -static void *get_any_partial(struct kmem_cache *s, struct partial_context *pc) > -{ > -#ifdef CONFIG_NUMA > - struct zonelist *zonelist; > - struct zoneref *z; > - struct zone *zone; > - enum zone_type highest_zoneidx = gfp_zone(pc->flags); > - void *object; > - unsigned int cpuset_mems_cookie; > - > - /* > - * The defrag ratio allows a configuration of the tradeoffs between > - * inter node defragmentation and node local allocations. A lower > - * defrag_ratio increases the tendency to do local allocations > - * instead of attempting to obtain partial slabs from other nodes. > - * > - * If the defrag_ratio is set to 0 then kmalloc() always > - * returns node local objects. If the ratio is higher then kmalloc() > - * may return off node objects because partial slabs are obtained > - * from other nodes and filled up. > - * > - * If /sys/kernel/slab/xx/remote_node_defrag_ratio is set to 100 > - * (which makes defrag_ratio = 1000) then every (well almost) > - * allocation will first attempt to defrag slab caches on other nodes. > - * This means scanning over all nodes to look for partial slabs which > - * may be expensive if we do it every time we are trying to find a slab > - * with available objects. > - */ > - if (!s->remote_node_defrag_ratio || > - get_cycles() % 1024 > s->remote_node_defrag_ratio) > - return NULL; > - > - do { > - cpuset_mems_cookie = read_mems_allowed_begin(); > - zonelist = node_zonelist(mempolicy_slab_node(), pc->flags); > - for_each_zone_zonelist(zone, z, zonelist, highest_zoneidx) { > - struct kmem_cache_node *n; > - > - n = get_node(s, zone_to_nid(zone)); > - > - if (n && cpuset_zone_allowed(zone, pc->flags) && > - n->nr_partial > s->min_partial) { > - object = get_partial_node(s, n, pc); > - if (object) { > - /* > - * Don't check read_mems_allowed_retry() > - * here - if mems_allowed was updated in > - * parallel, that was a harmless race > - * between allocation and the cpuset > - * update > - */ > - return object; > - } > - } > - } > - } while (read_mems_allowed_retry(cpuset_mems_cookie)); > -#endif /* CONFIG_NUMA */ > - return NULL; > -} > - > -/* > - * Get a partial slab, lock it and return it. > - */ > -static void *get_partial(struct kmem_cache *s, int node, struct partial_context *pc) > -{ > - void *object; > - int searchnode = node; > - > - if (node == NUMA_NO_NODE) > - searchnode = numa_mem_id(); > - > - object = get_partial_node(s, get_node(s, searchnode), pc); > - if (object || node != NUMA_NO_NODE) > - return object; > - > - return get_any_partial(s, pc); > -} > - > -#ifndef CONFIG_SLUB_TINY > - > -#ifdef CONFIG_PREEMPTION > -/* > - * Calculate the next globally unique transaction for disambiguation > - * during cmpxchg. The transactions start with the cpu number and are then > - * incremented by CONFIG_NR_CPUS. > - */ > -#define TID_STEP roundup_pow_of_two(CONFIG_NR_CPUS) > -#else > -/* > - * No preemption supported therefore also no need to check for > - * different cpus. > - */ > -#define TID_STEP 1 > -#endif /* CONFIG_PREEMPTION */ > - > -static inline unsigned long next_tid(unsigned long tid) > -{ > - return tid + TID_STEP; > -} > - > -#ifdef SLUB_DEBUG_CMPXCHG > -static inline unsigned int tid_to_cpu(unsigned long tid) > -{ > - return tid % TID_STEP; > -} > - > -static inline unsigned long tid_to_event(unsigned long tid) > -{ > - return tid / TID_STEP; > -} > -#endif > - > -static inline unsigned int init_tid(int cpu) > -{ > - return cpu; > -} > - > -static inline void note_cmpxchg_failure(const char *n, > - const struct kmem_cache *s, unsigned long tid) > -{ > -#ifdef SLUB_DEBUG_CMPXCHG > - unsigned long actual_tid = __this_cpu_read(s->cpu_slab->tid); > - > - pr_info("%s %s: cmpxchg redo ", n, s->name); > - > -#ifdef CONFIG_PREEMPTION > - if (tid_to_cpu(tid) != tid_to_cpu(actual_tid)) > - pr_warn("due to cpu change %d -> %d\n", > - tid_to_cpu(tid), tid_to_cpu(actual_tid)); > - else > -#endif > - if (tid_to_event(tid) != tid_to_event(actual_tid)) > - pr_warn("due to cpu running other code. Event %ld->%ld\n", > - tid_to_event(tid), tid_to_event(actual_tid)); > - else > - pr_warn("for unknown reason: actual=%lx was=%lx target=%lx\n", > - actual_tid, tid, next_tid(tid)); > -#endif > - stat(s, CMPXCHG_DOUBLE_CPU_FAIL); > -} > - > -static void init_kmem_cache_cpus(struct kmem_cache *s) > -{ > - int cpu; > - struct kmem_cache_cpu *c; > - > - for_each_possible_cpu(cpu) { > - c = per_cpu_ptr(s->cpu_slab, cpu); > - local_lock_init(&c->lock); > - c->tid = init_tid(cpu); > - } > -} > - > -/* > - * Finishes removing the cpu slab. Merges cpu's freelist with slab's freelist, > - * unfreezes the slabs and puts it on the proper list. > - * Assumes the slab has been already safely taken away from kmem_cache_cpu > - * by the caller. > - */ > -static void deactivate_slab(struct kmem_cache *s, struct slab *slab, > - void *freelist) > -{ > - enum slab_modes { M_NONE, M_PARTIAL, M_FREE, M_FULL_NOLIST }; > - struct kmem_cache_node *n = get_node(s, slab_nid(slab)); > - int free_delta = 0; > - enum slab_modes mode = M_NONE; > - void *nextfree, *freelist_iter, *freelist_tail; > - int tail = DEACTIVATE_TO_HEAD; > - unsigned long flags = 0; > - struct slab new; > - struct slab old; > - > - if (slab->freelist) { > - stat(s, DEACTIVATE_REMOTE_FREES); > - tail = DEACTIVATE_TO_TAIL; > - } > - > - /* > - * Stage one: Count the objects on cpu's freelist as free_delta and > - * remember the last object in freelist_tail for later splicing. > - */ > - freelist_tail = NULL; > - freelist_iter = freelist; > - while (freelist_iter) { > - nextfree = get_freepointer(s, freelist_iter); > - > - /* > - * If 'nextfree' is invalid, it is possible that the object at > - * 'freelist_iter' is already corrupted. So isolate all objects > - * starting at 'freelist_iter' by skipping them. > - */ > - if (freelist_corrupted(s, slab, &freelist_iter, nextfree)) > - break; > - > - freelist_tail = freelist_iter; > - free_delta++; > - > - freelist_iter = nextfree; > - } > - > - /* > - * Stage two: Unfreeze the slab while splicing the per-cpu > - * freelist to the head of slab's freelist. > - * > - * Ensure that the slab is unfrozen while the list presence > - * reflects the actual number of objects during unfreeze. > - * > - * We first perform cmpxchg holding lock and insert to list > - * when it succeed. If there is mismatch then the slab is not > - * unfrozen and number of objects in the slab may have changed. > - * Then release lock and retry cmpxchg again. > - */ > -redo: > - > - old.freelist = READ_ONCE(slab->freelist); > - old.counters = READ_ONCE(slab->counters); > - VM_BUG_ON(!old.frozen); > - > - /* Determine target state of the slab */ > - new.counters = old.counters; > - if (freelist_tail) { > - new.inuse -= free_delta; > - set_freepointer(s, freelist_tail, old.freelist); > - new.freelist = freelist; > - } else > - new.freelist = old.freelist; > - > - new.frozen = 0; > - > - if (!new.inuse && n->nr_partial >= s->min_partial) { > - mode = M_FREE; > - } else if (new.freelist) { > - mode = M_PARTIAL; > - /* > - * Taking the spinlock removes the possibility that > - * acquire_slab() will see a slab that is frozen > - */ > - spin_lock_irqsave(&n->list_lock, flags); > - } else { > - mode = M_FULL_NOLIST; > - } > - > - > - if (!cmpxchg_double_slab(s, slab, > - old.freelist, old.counters, > - new.freelist, new.counters, > - "unfreezing slab")) { > - if (mode == M_PARTIAL) > - spin_unlock_irqrestore(&n->list_lock, flags); > - goto redo; > - } > - > - > - if (mode == M_PARTIAL) { > - add_partial(n, slab, tail); > - spin_unlock_irqrestore(&n->list_lock, flags); > - stat(s, tail); > - } else if (mode == M_FREE) { > - stat(s, DEACTIVATE_EMPTY); > - discard_slab(s, slab); > - stat(s, FREE_SLAB); > - } else if (mode == M_FULL_NOLIST) { > - stat(s, DEACTIVATE_FULL); > - } > -} > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -static void __unfreeze_partials(struct kmem_cache *s, struct slab *partial_slab) > -{ > - struct kmem_cache_node *n = NULL, *n2 = NULL; > - struct slab *slab, *slab_to_discard = NULL; > - unsigned long flags = 0; > - > - while (partial_slab) { > - struct slab new; > - struct slab old; > - > - slab = partial_slab; > - partial_slab = slab->next; > - > - n2 = get_node(s, slab_nid(slab)); > - if (n != n2) { > - if (n) > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - n = n2; > - spin_lock_irqsave(&n->list_lock, flags); > - } > - > - do { > - > - old.freelist = slab->freelist; > - old.counters = slab->counters; > - VM_BUG_ON(!old.frozen); > - > - new.counters = old.counters; > - new.freelist = old.freelist; > - > - new.frozen = 0; > - > - } while (!__cmpxchg_double_slab(s, slab, > - old.freelist, old.counters, > - new.freelist, new.counters, > - "unfreezing slab")); > - > - if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) { > - slab->next = slab_to_discard; > - slab_to_discard = slab; > - } else { > - add_partial(n, slab, DEACTIVATE_TO_TAIL); > - stat(s, FREE_ADD_PARTIAL); > - } > - } > - > - if (n) > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - while (slab_to_discard) { > - slab = slab_to_discard; > - slab_to_discard = slab_to_discard->next; > - > - stat(s, DEACTIVATE_EMPTY); > - discard_slab(s, slab); > - stat(s, FREE_SLAB); > - } > -} > - > -/* > - * Unfreeze all the cpu partial slabs. > - */ > -static void unfreeze_partials(struct kmem_cache *s) > -{ > - struct slab *partial_slab; > - unsigned long flags; > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - partial_slab = this_cpu_read(s->cpu_slab->partial); > - this_cpu_write(s->cpu_slab->partial, NULL); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - if (partial_slab) > - __unfreeze_partials(s, partial_slab); > -} > - > -static void unfreeze_partials_cpu(struct kmem_cache *s, > - struct kmem_cache_cpu *c) > -{ > - struct slab *partial_slab; > - > - partial_slab = slub_percpu_partial(c); > - c->partial = NULL; > - > - if (partial_slab) > - __unfreeze_partials(s, partial_slab); > -} > - > -/* > - * Put a slab that was just frozen (in __slab_free|get_partial_node) into a > - * partial slab slot if available. > - * > - * If we did not find a slot then simply move all the partials to the > - * per node partial list. > - */ > -static void put_cpu_partial(struct kmem_cache *s, struct slab *slab, int drain) > -{ > - struct slab *oldslab; > - struct slab *slab_to_unfreeze = NULL; > - unsigned long flags; > - int slabs = 0; > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - > - oldslab = this_cpu_read(s->cpu_slab->partial); > - > - if (oldslab) { > - if (drain && oldslab->slabs >= s->cpu_partial_slabs) { > - /* > - * Partial array is full. Move the existing set to the > - * per node partial list. Postpone the actual unfreezing > - * outside of the critical section. > - */ > - slab_to_unfreeze = oldslab; > - oldslab = NULL; > - } else { > - slabs = oldslab->slabs; > - } > - } > - > - slabs++; > - > - slab->slabs = slabs; > - slab->next = oldslab; > - > - this_cpu_write(s->cpu_slab->partial, slab); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - if (slab_to_unfreeze) { > - __unfreeze_partials(s, slab_to_unfreeze); > - stat(s, CPU_PARTIAL_DRAIN); > - } > -} > - > -#else /* CONFIG_SLUB_CPU_PARTIAL */ > - > -static inline void unfreeze_partials(struct kmem_cache *s) { } > -static inline void unfreeze_partials_cpu(struct kmem_cache *s, > - struct kmem_cache_cpu *c) { } > - > -#endif /* CONFIG_SLUB_CPU_PARTIAL */ > - > -static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) > -{ > - unsigned long flags; > - struct slab *slab; > - void *freelist; > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - > - slab = c->slab; > - freelist = c->freelist; > - > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - if (slab) { > - deactivate_slab(s, slab, freelist); > - stat(s, CPUSLAB_FLUSH); > - } > -} > - > -static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) > -{ > - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); > - void *freelist = c->freelist; > - struct slab *slab = c->slab; > - > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - > - if (slab) { > - deactivate_slab(s, slab, freelist); > - stat(s, CPUSLAB_FLUSH); > - } > - > - unfreeze_partials_cpu(s, c); > -} > - > -struct slub_flush_work { > - struct work_struct work; > - struct kmem_cache *s; > - bool skip; > -}; > - > -/* > - * Flush cpu slab. > - * > - * Called from CPU work handler with migration disabled. > - */ > -static void flush_cpu_slab(struct work_struct *w) > -{ > - struct kmem_cache *s; > - struct kmem_cache_cpu *c; > - struct slub_flush_work *sfw; > - > - sfw = container_of(w, struct slub_flush_work, work); > - > - s = sfw->s; > - c = this_cpu_ptr(s->cpu_slab); > - > - if (c->slab) > - flush_slab(s, c); > - > - unfreeze_partials(s); > -} > - > -static bool has_cpu_slab(int cpu, struct kmem_cache *s) > -{ > - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); > - > - return c->slab || slub_percpu_partial(c); > -} > - > -static DEFINE_MUTEX(flush_lock); > -static DEFINE_PER_CPU(struct slub_flush_work, slub_flush); > - > -static void flush_all_cpus_locked(struct kmem_cache *s) > -{ > - struct slub_flush_work *sfw; > - unsigned int cpu; > - > - lockdep_assert_cpus_held(); > - mutex_lock(&flush_lock); > - > - for_each_online_cpu(cpu) { > - sfw = &per_cpu(slub_flush, cpu); > - if (!has_cpu_slab(cpu, s)) { > - sfw->skip = true; > - continue; > - } > - INIT_WORK(&sfw->work, flush_cpu_slab); > - sfw->skip = false; > - sfw->s = s; > - queue_work_on(cpu, flushwq, &sfw->work); > - } > - > - for_each_online_cpu(cpu) { > - sfw = &per_cpu(slub_flush, cpu); > - if (sfw->skip) > - continue; > - flush_work(&sfw->work); > - } > - > - mutex_unlock(&flush_lock); > -} > - > -static void flush_all(struct kmem_cache *s) > -{ > - cpus_read_lock(); > - flush_all_cpus_locked(s); > - cpus_read_unlock(); > -} > - > -/* > - * Use the cpu notifier to insure that the cpu slabs are flushed when > - * necessary. > - */ > -static int slub_cpu_dead(unsigned int cpu) > -{ > - struct kmem_cache *s; > - > - mutex_lock(&slab_mutex); > - list_for_each_entry(s, &slab_caches, list) > - __flush_cpu_slab(s, cpu); > - mutex_unlock(&slab_mutex); > - return 0; > -} > - > -#else /* CONFIG_SLUB_TINY */ > -static inline void flush_all_cpus_locked(struct kmem_cache *s) { } > -static inline void flush_all(struct kmem_cache *s) { } > -static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) { } > -static inline int slub_cpu_dead(unsigned int cpu) { return 0; } > -#endif /* CONFIG_SLUB_TINY */ > - > -/* > - * Check if the objects in a per cpu structure fit numa > - * locality expectations. > - */ > -static inline int node_match(struct slab *slab, int node) > -{ > -#ifdef CONFIG_NUMA > - if (node != NUMA_NO_NODE && slab_nid(slab) != node) > - return 0; > -#endif > - return 1; > -} > - > -#ifdef CONFIG_SLUB_DEBUG > -static int count_free(struct slab *slab) > -{ > - return slab->objects - slab->inuse; > -} > - > -static inline unsigned long node_nr_objs(struct kmem_cache_node *n) > -{ > - return atomic_long_read(&n->total_objects); > -} > - > -/* Supports checking bulk free of a constructed freelist */ > -static inline bool free_debug_processing(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, int *bulk_cnt, > - unsigned long addr, depot_stack_handle_t handle) > -{ > - bool checks_ok = false; > - void *object = head; > - int cnt = 0; > - > - if (s->flags & SLAB_CONSISTENCY_CHECKS) { > - if (!check_slab(s, slab)) > - goto out; > - } > - > - if (slab->inuse < *bulk_cnt) { > - slab_err(s, slab, "Slab has %d allocated objects but %d are to be freed\n", > - slab->inuse, *bulk_cnt); > - goto out; > - } > - > -next_object: > - > - if (++cnt > *bulk_cnt) > - goto out_cnt; > - > - if (s->flags & SLAB_CONSISTENCY_CHECKS) { > - if (!free_consistency_checks(s, slab, object, addr)) > - goto out; > - } > - > - if (s->flags & SLAB_STORE_USER) > - set_track_update(s, object, TRACK_FREE, addr, handle); > - trace(s, slab, object, 0); > - /* Freepointer not overwritten by init_object(), SLAB_POISON moved it */ > - init_object(s, object, SLUB_RED_INACTIVE); > - > - /* Reached end of constructed freelist yet? */ > - if (object != tail) { > - object = get_freepointer(s, object); > - goto next_object; > - } > - checks_ok = true; > - > -out_cnt: > - if (cnt != *bulk_cnt) { > - slab_err(s, slab, "Bulk free expected %d objects but found %d\n", > - *bulk_cnt, cnt); > - *bulk_cnt = cnt; > - } > - > -out: > - > - if (!checks_ok) > - slab_fix(s, "Object at 0x%p not freed", object); > - > - return checks_ok; > -} > -#endif /* CONFIG_SLUB_DEBUG */ > - > -#if defined(CONFIG_SLUB_DEBUG) || defined(SLAB_SUPPORTS_SYSFS) > -static unsigned long count_partial(struct kmem_cache_node *n, > - int (*get_count)(struct slab *)) > -{ > - unsigned long flags; > - unsigned long x = 0; > - struct slab *slab; > - > - spin_lock_irqsave(&n->list_lock, flags); > - list_for_each_entry(slab, &n->partial, slab_list) > - x += get_count(slab); > - spin_unlock_irqrestore(&n->list_lock, flags); > - return x; > -} > -#endif /* CONFIG_SLUB_DEBUG || SLAB_SUPPORTS_SYSFS */ > - > -#ifdef CONFIG_SLUB_DEBUG > -static noinline void > -slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) > -{ > - static DEFINE_RATELIMIT_STATE(slub_oom_rs, DEFAULT_RATELIMIT_INTERVAL, > - DEFAULT_RATELIMIT_BURST); > - int node; > - struct kmem_cache_node *n; > - > - if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slub_oom_rs)) > - return; > - > - pr_warn("SLUB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", > - nid, gfpflags, &gfpflags); > - pr_warn(" cache: %s, object size: %u, buffer size: %u, default order: %u, min order: %u\n", > - s->name, s->object_size, s->size, oo_order(s->oo), > - oo_order(s->min)); > - > - if (oo_order(s->min) > get_order(s->object_size)) > - pr_warn(" %s debugging increased min order, use slub_debug=O to disable.\n", > - s->name); > - > - for_each_kmem_cache_node(s, node, n) { > - unsigned long nr_slabs; > - unsigned long nr_objs; > - unsigned long nr_free; > - > - nr_free = count_partial(n, count_free); > - nr_slabs = node_nr_slabs(n); > - nr_objs = node_nr_objs(n); > - > - pr_warn(" node %d: slabs: %ld, objs: %ld, free: %ld\n", > - node, nr_slabs, nr_objs, nr_free); > - } > -} > -#else /* CONFIG_SLUB_DEBUG */ > -static inline void > -slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) { } > -#endif > - > -static inline bool pfmemalloc_match(struct slab *slab, gfp_t gfpflags) > -{ > - if (unlikely(slab_test_pfmemalloc(slab))) > - return gfp_pfmemalloc_allowed(gfpflags); > - > - return true; > -} > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Check the slab->freelist and either transfer the freelist to the > - * per cpu freelist or deactivate the slab. > - * > - * The slab is still frozen if the return value is not NULL. > - * > - * If this function returns NULL then the slab has been unfrozen. > - */ > -static inline void *get_freelist(struct kmem_cache *s, struct slab *slab) > -{ > - struct slab new; > - unsigned long counters; > - void *freelist; > - > - lockdep_assert_held(this_cpu_ptr(&s->cpu_slab->lock)); > - > - do { > - freelist = slab->freelist; > - counters = slab->counters; > - > - new.counters = counters; > - VM_BUG_ON(!new.frozen); > - > - new.inuse = slab->objects; > - new.frozen = freelist != NULL; > - > - } while (!__cmpxchg_double_slab(s, slab, > - freelist, counters, > - NULL, new.counters, > - "get_freelist")); > - > - return freelist; > -} > - > -/* > - * Slow path. The lockless freelist is empty or we need to perform > - * debugging duties. > - * > - * Processing is still very fast if new objects have been freed to the > - * regular freelist. In that case we simply take over the regular freelist > - * as the lockless freelist and zap the regular freelist. > - * > - * If that is not working then we fall back to the partial lists. We take the > - * first element of the freelist as the object to allocate now and move the > - * rest of the freelist to the lockless freelist. > - * > - * And if we were unable to get a new slab from the partial slab lists then > - * we need to allocate a new slab. This is the slowest path since it involves > - * a call to the page allocator and the setup of a new slab. > - * > - * Version of __slab_alloc to use when we know that preemption is > - * already disabled (which is the case for bulk allocation). > - */ > -static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, > - unsigned long addr, struct kmem_cache_cpu *c, unsigned int orig_size) > -{ > - void *freelist; > - struct slab *slab; > - unsigned long flags; > - struct partial_context pc; > - > - stat(s, ALLOC_SLOWPATH); > - > -reread_slab: > - > - slab = READ_ONCE(c->slab); > - if (!slab) { > - /* > - * if the node is not online or has no normal memory, just > - * ignore the node constraint > - */ > - if (unlikely(node != NUMA_NO_NODE && > - !node_isset(node, slab_nodes))) > - node = NUMA_NO_NODE; > - goto new_slab; > - } > -redo: > - > - if (unlikely(!node_match(slab, node))) { > - /* > - * same as above but node_match() being false already > - * implies node != NUMA_NO_NODE > - */ > - if (!node_isset(node, slab_nodes)) { > - node = NUMA_NO_NODE; > - } else { > - stat(s, ALLOC_NODE_MISMATCH); > - goto deactivate_slab; > - } > - } > - > - /* > - * By rights, we should be searching for a slab page that was > - * PFMEMALLOC but right now, we are losing the pfmemalloc > - * information when the page leaves the per-cpu allocator > - */ > - if (unlikely(!pfmemalloc_match(slab, gfpflags))) > - goto deactivate_slab; > - > - /* must check again c->slab in case we got preempted and it changed */ > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (unlikely(slab != c->slab)) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - goto reread_slab; > - } > - freelist = c->freelist; > - if (freelist) > - goto load_freelist; > - > - freelist = get_freelist(s, slab); > - > - if (!freelist) { > - c->slab = NULL; > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - stat(s, DEACTIVATE_BYPASS); > - goto new_slab; > - } > - > - stat(s, ALLOC_REFILL); > - > -load_freelist: > - > - lockdep_assert_held(this_cpu_ptr(&s->cpu_slab->lock)); > - > - /* > - * freelist is pointing to the list of objects to be used. > - * slab is pointing to the slab from which the objects are obtained. > - * That slab must be frozen for per cpu allocations to work. > - */ > - VM_BUG_ON(!c->slab->frozen); > - c->freelist = get_freepointer(s, freelist); > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - return freelist; > - > -deactivate_slab: > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (slab != c->slab) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - goto reread_slab; > - } > - freelist = c->freelist; > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - deactivate_slab(s, slab, freelist); > - > -new_slab: > - > - if (slub_percpu_partial(c)) { > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (unlikely(c->slab)) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - goto reread_slab; > - } > - if (unlikely(!slub_percpu_partial(c))) { > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - /* we were preempted and partial list got empty */ > - goto new_objects; > - } > - > - slab = c->slab = slub_percpu_partial(c); > - slub_set_percpu_partial(c, slab); > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - stat(s, CPU_PARTIAL_ALLOC); > - goto redo; > - } > - > -new_objects: > - > - pc.flags = gfpflags; > - pc.slab = &slab; > - pc.orig_size = orig_size; > - freelist = get_partial(s, node, &pc); > - if (freelist) > - goto check_new_slab; > - > - slub_put_cpu_ptr(s->cpu_slab); > - slab = new_slab(s, gfpflags, node); > - c = slub_get_cpu_ptr(s->cpu_slab); > - > - if (unlikely(!slab)) { > - slab_out_of_memory(s, gfpflags, node); > - return NULL; > - } > - > - stat(s, ALLOC_SLAB); > - > - if (kmem_cache_debug(s)) { > - freelist = alloc_single_from_new_slab(s, slab, orig_size); > - > - if (unlikely(!freelist)) > - goto new_objects; > - > - if (s->flags & SLAB_STORE_USER) > - set_track(s, freelist, TRACK_ALLOC, addr); > - > - return freelist; > - } > - > - /* > - * No other reference to the slab yet so we can > - * muck around with it freely without cmpxchg > - */ > - freelist = slab->freelist; > - slab->freelist = NULL; > - slab->inuse = slab->objects; > - slab->frozen = 1; > - > - inc_slabs_node(s, slab_nid(slab), slab->objects); > - > -check_new_slab: > - > - if (kmem_cache_debug(s)) { > - /* > - * For debug caches here we had to go through > - * alloc_single_from_partial() so just store the tracking info > - * and return the object > - */ > - if (s->flags & SLAB_STORE_USER) > - set_track(s, freelist, TRACK_ALLOC, addr); > - > - return freelist; > - } > - > - if (unlikely(!pfmemalloc_match(slab, gfpflags))) { > - /* > - * For !pfmemalloc_match() case we don't load freelist so that > - * we don't make further mismatched allocations easier. > - */ > - deactivate_slab(s, slab, get_freepointer(s, freelist)); > - return freelist; > - } > - > -retry_load_slab: > - > - local_lock_irqsave(&s->cpu_slab->lock, flags); > - if (unlikely(c->slab)) { > - void *flush_freelist = c->freelist; > - struct slab *flush_slab = c->slab; > - > - c->slab = NULL; > - c->freelist = NULL; > - c->tid = next_tid(c->tid); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, flags); > - > - deactivate_slab(s, flush_slab, flush_freelist); > - > - stat(s, CPUSLAB_FLUSH); > - > - goto retry_load_slab; > - } > - c->slab = slab; > - > - goto load_freelist; > -} > - > -/* > - * A wrapper for ___slab_alloc() for contexts where preemption is not yet > - * disabled. Compensates for possible cpu changes by refetching the per cpu area > - * pointer. > - */ > -static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, > - unsigned long addr, struct kmem_cache_cpu *c, unsigned int orig_size) > -{ > - void *p; > - > -#ifdef CONFIG_PREEMPT_COUNT > - /* > - * We may have been preempted and rescheduled on a different > - * cpu before disabling preemption. Need to reload cpu area > - * pointer. > - */ > - c = slub_get_cpu_ptr(s->cpu_slab); > -#endif > - > - p = ___slab_alloc(s, gfpflags, node, addr, c, orig_size); > -#ifdef CONFIG_PREEMPT_COUNT > - slub_put_cpu_ptr(s->cpu_slab); > -#endif > - return p; > -} > - > -static __always_inline void *__slab_alloc_node(struct kmem_cache *s, > - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) > -{ > - struct kmem_cache_cpu *c; > - struct slab *slab; > - unsigned long tid; > - void *object; > - > -redo: > - /* > - * Must read kmem_cache cpu data via this cpu ptr. Preemption is > - * enabled. We may switch back and forth between cpus while > - * reading from one cpu area. That does not matter as long > - * as we end up on the original cpu again when doing the cmpxchg. > - * > - * We must guarantee that tid and kmem_cache_cpu are retrieved on the > - * same cpu. We read first the kmem_cache_cpu pointer and use it to read > - * the tid. If we are preempted and switched to another cpu between the > - * two reads, it's OK as the two are still associated with the same cpu > - * and cmpxchg later will validate the cpu. > - */ > - c = raw_cpu_ptr(s->cpu_slab); > - tid = READ_ONCE(c->tid); > - > - /* > - * Irqless object alloc/free algorithm used here depends on sequence > - * of fetching cpu_slab's data. tid should be fetched before anything > - * on c to guarantee that object and slab associated with previous tid > - * won't be used with current tid. If we fetch tid first, object and > - * slab could be one associated with next tid and our alloc/free > - * request will be failed. In this case, we will retry. So, no problem. > - */ > - barrier(); > - > - /* > - * The transaction ids are globally unique per cpu and per operation on > - * a per cpu queue. Thus they can be guarantee that the cmpxchg_double > - * occurs on the right processor and that there was no operation on the > - * linked list in between. > - */ > - > - object = c->freelist; > - slab = c->slab; > - > - if (!USE_LOCKLESS_FAST_PATH() || > - unlikely(!object || !slab || !node_match(slab, node))) { > - object = __slab_alloc(s, gfpflags, node, addr, c, orig_size); > - } else { > - void *next_object = get_freepointer_safe(s, object); > - > - /* > - * The cmpxchg will only match if there was no additional > - * operation and if we are on the right processor. > - * > - * The cmpxchg does the following atomically (without lock > - * semantics!) > - * 1. Relocate first pointer to the current per cpu area. > - * 2. Verify that tid and freelist have not been changed > - * 3. If they were not changed replace tid and freelist > - * > - * Since this is without lock semantics the protection is only > - * against code executing on this cpu *not* from access by > - * other cpus. > - */ > - if (unlikely(!this_cpu_cmpxchg_double( > - s->cpu_slab->freelist, s->cpu_slab->tid, > - object, tid, > - next_object, next_tid(tid)))) { > - > - note_cmpxchg_failure("slab_alloc", s, tid); > - goto redo; > - } > - prefetch_freepointer(s, next_object); > - stat(s, ALLOC_FASTPATH); > - } > - > - return object; > -} > -#else /* CONFIG_SLUB_TINY */ > -static void *__slab_alloc_node(struct kmem_cache *s, > - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) > -{ > - struct partial_context pc; > - struct slab *slab; > - void *object; > - > - pc.flags = gfpflags; > - pc.slab = &slab; > - pc.orig_size = orig_size; > - object = get_partial(s, node, &pc); > - > - if (object) > - return object; > - > - slab = new_slab(s, gfpflags, node); > - if (unlikely(!slab)) { > - slab_out_of_memory(s, gfpflags, node); > - return NULL; > - } > - > - object = alloc_single_from_new_slab(s, slab, orig_size); > - > - return object; > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -/* > - * If the object has been wiped upon free, make sure it's fully initialized by > - * zeroing out freelist pointer. > - */ > -static __always_inline void maybe_wipe_obj_freeptr(struct kmem_cache *s, > - void *obj) > -{ > - if (unlikely(slab_want_init_on_free(s)) && obj) > - memset((void *)((char *)kasan_reset_tag(obj) + s->offset), > - 0, sizeof(void *)); > -} > - > -/* > - * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc) > - * have the fastpath folded into their functions. So no function call > - * overhead for requests that can be satisfied on the fastpath. > - * > - * The fastpath works by first checking if the lockless freelist can be used. > - * If not then __slab_alloc is called for slow processing. > - * > - * Otherwise we can simply pick the next object from the lockless free list. > - */ > -static __fastpath_inline void *slab_alloc_node(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) > -{ > - void *object; > - struct obj_cgroup *objcg = NULL; > - bool init = false; > - > - s = slab_pre_alloc_hook(s, lru, &objcg, 1, gfpflags); > - if (!s) > - return NULL; > - > - object = kfence_alloc(s, orig_size, gfpflags); > - if (unlikely(object)) > - goto out; > - > - object = __slab_alloc_node(s, gfpflags, node, addr, orig_size); > - > - maybe_wipe_obj_freeptr(s, object); > - init = slab_want_init_on_alloc(gfpflags, s); > - > -out: > - /* > - * When init equals 'true', like for kzalloc() family, only > - * @orig_size bytes might be zeroed instead of s->object_size > - */ > - slab_post_alloc_hook(s, objcg, gfpflags, 1, &object, init, orig_size); > - > - return object; > -} > - > -static __fastpath_inline void *slab_alloc(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags, unsigned long addr, size_t orig_size) > -{ > - return slab_alloc_node(s, lru, gfpflags, NUMA_NO_NODE, addr, orig_size); > -} > - > -static __fastpath_inline > -void *__kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags) > -{ > - void *ret = slab_alloc(s, lru, gfpflags, _RET_IP_, s->object_size); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, s, gfpflags, NUMA_NO_NODE); > - > - return ret; > -} > - > -void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) > -{ > - return __kmem_cache_alloc_lru(s, NULL, gfpflags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc); > - > -void *kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, > - gfp_t gfpflags) > -{ > - return __kmem_cache_alloc_lru(s, lru, gfpflags); > -} > -EXPORT_SYMBOL(kmem_cache_alloc_lru); > - > -void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, > - int node, size_t orig_size, > - unsigned long caller) > -{ > - return slab_alloc_node(s, NULL, gfpflags, node, > - caller, orig_size); > -} > - > -void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node) > -{ > - void *ret = slab_alloc_node(s, NULL, gfpflags, node, _RET_IP_, s->object_size); > - > - trace_kmem_cache_alloc(_RET_IP_, ret, s, gfpflags, node); > - > - return ret; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_node); > - > -static noinline void free_to_partial_list( > - struct kmem_cache *s, struct slab *slab, > - void *head, void *tail, int bulk_cnt, > - unsigned long addr) > -{ > - struct kmem_cache_node *n = get_node(s, slab_nid(slab)); > - struct slab *slab_free = NULL; > - int cnt = bulk_cnt; > - unsigned long flags; > - depot_stack_handle_t handle = 0; > - > - if (s->flags & SLAB_STORE_USER) > - handle = set_track_prepare(); > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - if (free_debug_processing(s, slab, head, tail, &cnt, addr, handle)) { > - void *prior = slab->freelist; > - > - /* Perform the actual freeing while we still hold the locks */ > - slab->inuse -= cnt; > - set_freepointer(s, tail, prior); > - slab->freelist = head; > - > - /* > - * If the slab is empty, and node's partial list is full, > - * it should be discarded anyway no matter it's on full or > - * partial list. > - */ > - if (slab->inuse == 0 && n->nr_partial >= s->min_partial) > - slab_free = slab; > - > - if (!prior) { > - /* was on full list */ > - remove_full(s, n, slab); > - if (!slab_free) { > - add_partial(n, slab, DEACTIVATE_TO_TAIL); > - stat(s, FREE_ADD_PARTIAL); > - } > - } else if (slab_free) { > - remove_partial(n, slab); > - stat(s, FREE_REMOVE_PARTIAL); > - } > - } > - > - if (slab_free) { > - /* > - * Update the counters while still holding n->list_lock to > - * prevent spurious validation warnings > - */ > - dec_slabs_node(s, slab_nid(slab_free), slab_free->objects); > - } > - > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - if (slab_free) { > - stat(s, FREE_SLAB); > - free_slab(s, slab_free); > - } > -} > - > -/* > - * Slow path handling. This may still be called frequently since objects > - * have a longer lifetime than the cpu slabs in most processing loads. > - * > - * So we still attempt to reduce cache line usage. Just take the slab > - * lock and free the item. If there is no additional partial slab > - * handling required then we can return immediately. > - */ > -static void __slab_free(struct kmem_cache *s, struct slab *slab, > - void *head, void *tail, int cnt, > - unsigned long addr) > - > -{ > - void *prior; > - int was_frozen; > - struct slab new; > - unsigned long counters; > - struct kmem_cache_node *n = NULL; > - unsigned long flags; > - > - stat(s, FREE_SLOWPATH); > - > - if (kfence_free(head)) > - return; > - > - if (IS_ENABLED(CONFIG_SLUB_TINY) || kmem_cache_debug(s)) { > - free_to_partial_list(s, slab, head, tail, cnt, addr); > - return; > - } > - > - do { > - if (unlikely(n)) { > - spin_unlock_irqrestore(&n->list_lock, flags); > - n = NULL; > - } > - prior = slab->freelist; > - counters = slab->counters; > - set_freepointer(s, tail, prior); > - new.counters = counters; > - was_frozen = new.frozen; > - new.inuse -= cnt; > - if ((!new.inuse || !prior) && !was_frozen) { > - > - if (kmem_cache_has_cpu_partial(s) && !prior) { > - > - /* > - * Slab was on no list before and will be > - * partially empty > - * We can defer the list move and instead > - * freeze it. > - */ > - new.frozen = 1; > - > - } else { /* Needs to be taken off a list */ > - > - n = get_node(s, slab_nid(slab)); > - /* > - * Speculatively acquire the list_lock. > - * If the cmpxchg does not succeed then we may > - * drop the list_lock without any processing. > - * > - * Otherwise the list_lock will synchronize with > - * other processors updating the list of slabs. > - */ > - spin_lock_irqsave(&n->list_lock, flags); > - > - } > - } > - > - } while (!cmpxchg_double_slab(s, slab, > - prior, counters, > - head, new.counters, > - "__slab_free")); > - > - if (likely(!n)) { > - > - if (likely(was_frozen)) { > - /* > - * The list lock was not taken therefore no list > - * activity can be necessary. > - */ > - stat(s, FREE_FROZEN); > - } else if (new.frozen) { > - /* > - * If we just froze the slab then put it onto the > - * per cpu partial list. > - */ > - put_cpu_partial(s, slab, 1); > - stat(s, CPU_PARTIAL_FREE); > - } > - > - return; > - } > - > - if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) > - goto slab_empty; > - > - /* > - * Objects left in the slab. If it was not on the partial list before > - * then add it. > - */ > - if (!kmem_cache_has_cpu_partial(s) && unlikely(!prior)) { > - remove_full(s, n, slab); > - add_partial(n, slab, DEACTIVATE_TO_TAIL); > - stat(s, FREE_ADD_PARTIAL); > - } > - spin_unlock_irqrestore(&n->list_lock, flags); > - return; > - > -slab_empty: > - if (prior) { > - /* > - * Slab on the partial list. > - */ > - remove_partial(n, slab); > - stat(s, FREE_REMOVE_PARTIAL); > - } else { > - /* Slab must be on the full list */ > - remove_full(s, n, slab); > - } > - > - spin_unlock_irqrestore(&n->list_lock, flags); > - stat(s, FREE_SLAB); > - discard_slab(s, slab); > -} > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * Fastpath with forced inlining to produce a kfree and kmem_cache_free that > - * can perform fastpath freeing without additional function calls. > - * > - * The fastpath is only possible if we are freeing to the current cpu slab > - * of this processor. This typically the case if we have just allocated > - * the item before. > - * > - * If fastpath is not possible then fall back to __slab_free where we deal > - * with all sorts of special processing. > - * > - * Bulk free of a freelist with several objects (all pointing to the > - * same slab) possible by specifying head and tail ptr, plus objects > - * count (cnt). Bulk free indicated by tail pointer being set. > - */ > -static __always_inline void do_slab_free(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, > - int cnt, unsigned long addr) > -{ > - void *tail_obj = tail ? : head; > - struct kmem_cache_cpu *c; > - unsigned long tid; > - void **freelist; > - > -redo: > - /* > - * Determine the currently cpus per cpu slab. > - * The cpu may change afterward. However that does not matter since > - * data is retrieved via this pointer. If we are on the same cpu > - * during the cmpxchg then the free will succeed. > - */ > - c = raw_cpu_ptr(s->cpu_slab); > - tid = READ_ONCE(c->tid); > - > - /* Same with comment on barrier() in slab_alloc_node() */ > - barrier(); > - > - if (unlikely(slab != c->slab)) { > - __slab_free(s, slab, head, tail_obj, cnt, addr); > - return; > - } > - > - if (USE_LOCKLESS_FAST_PATH()) { > - freelist = READ_ONCE(c->freelist); > - > - set_freepointer(s, tail_obj, freelist); > - > - if (unlikely(!this_cpu_cmpxchg_double( > - s->cpu_slab->freelist, s->cpu_slab->tid, > - freelist, tid, > - head, next_tid(tid)))) { > - > - note_cmpxchg_failure("slab_free", s, tid); > - goto redo; > - } > - } else { > - /* Update the free list under the local lock */ > - local_lock(&s->cpu_slab->lock); > - c = this_cpu_ptr(s->cpu_slab); > - if (unlikely(slab != c->slab)) { > - local_unlock(&s->cpu_slab->lock); > - goto redo; > - } > - tid = c->tid; > - freelist = c->freelist; > - > - set_freepointer(s, tail_obj, freelist); > - c->freelist = head; > - c->tid = next_tid(tid); > - > - local_unlock(&s->cpu_slab->lock); > - } > - stat(s, FREE_FASTPATH); > -} > -#else /* CONFIG_SLUB_TINY */ > -static void do_slab_free(struct kmem_cache *s, > - struct slab *slab, void *head, void *tail, > - int cnt, unsigned long addr) > -{ > - void *tail_obj = tail ? : head; > - > - __slab_free(s, slab, head, tail_obj, cnt, addr); > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -static __fastpath_inline void slab_free(struct kmem_cache *s, struct slab *slab, > - void *head, void *tail, void **p, int cnt, > - unsigned long addr) > -{ > - memcg_slab_free_hook(s, slab, p, cnt); > - /* > - * With KASAN enabled slab_free_freelist_hook modifies the freelist > - * to remove objects, whose reuse must be delayed. > - */ > - if (slab_free_freelist_hook(s, &head, &tail, &cnt)) > - do_slab_free(s, slab, head, tail, cnt, addr); > -} > - > -#ifdef CONFIG_KASAN_GENERIC > -void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr) > -{ > - do_slab_free(cache, virt_to_slab(x), x, NULL, 1, addr); > -} > -#endif > - > -void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller) > -{ > - slab_free(s, virt_to_slab(x), x, NULL, &x, 1, caller); > -} > - > -void kmem_cache_free(struct kmem_cache *s, void *x) > -{ > - s = cache_from_obj(s, x); > - if (!s) > - return; > - trace_kmem_cache_free(_RET_IP_, x, s); > - slab_free(s, virt_to_slab(x), x, NULL, &x, 1, _RET_IP_); > -} > -EXPORT_SYMBOL(kmem_cache_free); > - > -struct detached_freelist { > - struct slab *slab; > - void *tail; > - void *freelist; > - int cnt; > - struct kmem_cache *s; > -}; > - > -/* > - * This function progressively scans the array with free objects (with > - * a limited look ahead) and extract objects belonging to the same > - * slab. It builds a detached freelist directly within the given > - * slab/objects. This can happen without any need for > - * synchronization, because the objects are owned by running process. > - * The freelist is build up as a single linked list in the objects. > - * The idea is, that this detached freelist can then be bulk > - * transferred to the real freelist(s), but only requiring a single > - * synchronization primitive. Look ahead in the array is limited due > - * to performance reasons. > - */ > -static inline > -int build_detached_freelist(struct kmem_cache *s, size_t size, > - void **p, struct detached_freelist *df) > -{ > - int lookahead = 3; > - void *object; > - struct folio *folio; > - size_t same; > - > - object = p[--size]; > - folio = virt_to_folio(object); > - if (!s) { > - /* Handle kalloc'ed objects */ > - if (unlikely(!folio_test_slab(folio))) { > - free_large_kmalloc(folio, object); > - df->slab = NULL; > - return size; > - } > - /* Derive kmem_cache from object */ > - df->slab = folio_slab(folio); > - df->s = df->slab->slab_cache; > - } else { > - df->slab = folio_slab(folio); > - df->s = cache_from_obj(s, object); /* Support for memcg */ > - } > - > - /* Start new detached freelist */ > - df->tail = object; > - df->freelist = object; > - df->cnt = 1; > - > - if (is_kfence_address(object)) > - return size; > - > - set_freepointer(df->s, object, NULL); > - > - same = size; > - while (size) { > - object = p[--size]; > - /* df->slab is always set at this point */ > - if (df->slab == virt_to_slab(object)) { > - /* Opportunity build freelist */ > - set_freepointer(df->s, object, df->freelist); > - df->freelist = object; > - df->cnt++; > - same--; > - if (size != same) > - swap(p[size], p[same]); > - continue; > - } > - > - /* Limit look ahead search */ > - if (!--lookahead) > - break; > - } > - > - return same; > -} > - > -/* Note that interrupts must be enabled when calling this function. */ > -void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p) > -{ > - if (!size) > - return; > - > - do { > - struct detached_freelist df; > - > - size = build_detached_freelist(s, size, p, &df); > - if (!df.slab) > - continue; > - > - slab_free(df.s, df.slab, df.freelist, df.tail, &p[size], df.cnt, > - _RET_IP_); > - } while (likely(size)); > -} > -EXPORT_SYMBOL(kmem_cache_free_bulk); > - > -#ifndef CONFIG_SLUB_TINY > -static inline int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, > - size_t size, void **p, struct obj_cgroup *objcg) > -{ > - struct kmem_cache_cpu *c; > - unsigned long irqflags; > - int i; > - > - /* > - * Drain objects in the per cpu slab, while disabling local > - * IRQs, which protects against PREEMPT and interrupts > - * handlers invoking normal fastpath. > - */ > - c = slub_get_cpu_ptr(s->cpu_slab); > - local_lock_irqsave(&s->cpu_slab->lock, irqflags); > - > - for (i = 0; i < size; i++) { > - void *object = kfence_alloc(s, s->object_size, flags); > - > - if (unlikely(object)) { > - p[i] = object; > - continue; > - } > - > - object = c->freelist; > - if (unlikely(!object)) { > - /* > - * We may have removed an object from c->freelist using > - * the fastpath in the previous iteration; in that case, > - * c->tid has not been bumped yet. > - * Since ___slab_alloc() may reenable interrupts while > - * allocating memory, we should bump c->tid now. > - */ > - c->tid = next_tid(c->tid); > - > - local_unlock_irqrestore(&s->cpu_slab->lock, irqflags); > - > - /* > - * Invoking slow path likely have side-effect > - * of re-populating per CPU c->freelist > - */ > - p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE, > - _RET_IP_, c, s->object_size); > - if (unlikely(!p[i])) > - goto error; > - > - c = this_cpu_ptr(s->cpu_slab); > - maybe_wipe_obj_freeptr(s, p[i]); > - > - local_lock_irqsave(&s->cpu_slab->lock, irqflags); > - > - continue; /* goto for-loop */ > - } > - c->freelist = get_freepointer(s, object); > - p[i] = object; > - maybe_wipe_obj_freeptr(s, p[i]); > - } > - c->tid = next_tid(c->tid); > - local_unlock_irqrestore(&s->cpu_slab->lock, irqflags); > - slub_put_cpu_ptr(s->cpu_slab); > - > - return i; > - > -error: > - slub_put_cpu_ptr(s->cpu_slab); > - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); > - kmem_cache_free_bulk(s, i, p); > - return 0; > - > -} > -#else /* CONFIG_SLUB_TINY */ > -static int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, > - size_t size, void **p, struct obj_cgroup *objcg) > -{ > - int i; > - > - for (i = 0; i < size; i++) { > - void *object = kfence_alloc(s, s->object_size, flags); > - > - if (unlikely(object)) { > - p[i] = object; > - continue; > - } > - > - p[i] = __slab_alloc_node(s, flags, NUMA_NO_NODE, > - _RET_IP_, s->object_size); > - if (unlikely(!p[i])) > - goto error; > - > - maybe_wipe_obj_freeptr(s, p[i]); > - } > - > - return i; > - > -error: > - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); > - kmem_cache_free_bulk(s, i, p); > - return 0; > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -/* Note that interrupts must be enabled when calling this function. */ > -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, > - void **p) > -{ > - int i; > - struct obj_cgroup *objcg = NULL; > - > - if (!size) > - return 0; > - > - /* memcg and kmem_cache debug support */ > - s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); > - if (unlikely(!s)) > - return 0; > - > - i = __kmem_cache_alloc_bulk(s, flags, size, p, objcg); > - > - /* > - * memcg and kmem_cache debug support and memory initialization. > - * Done outside of the IRQ disabled fastpath loop. > - */ > - if (i != 0) > - slab_post_alloc_hook(s, objcg, flags, size, p, > - slab_want_init_on_alloc(flags, s), s->object_size); > - return i; > -} > -EXPORT_SYMBOL(kmem_cache_alloc_bulk); > - > - > -/* > - * Object placement in a slab is made very easy because we always start at > - * offset 0. If we tune the size of the object to the alignment then we can > - * get the required alignment by putting one properly sized object after > - * another. > - * > - * Notice that the allocation order determines the sizes of the per cpu > - * caches. Each processor has always one slab available for allocations. > - * Increasing the allocation order reduces the number of times that slabs > - * must be moved on and off the partial lists and is therefore a factor in > - * locking overhead. > - */ > - > -/* > - * Minimum / Maximum order of slab pages. This influences locking overhead > - * and slab fragmentation. A higher order reduces the number of partial slabs > - * and increases the number of allocations possible without having to > - * take the list_lock. > - */ > -static unsigned int slub_min_order; > -static unsigned int slub_max_order = > - IS_ENABLED(CONFIG_SLUB_TINY) ? 1 : PAGE_ALLOC_COSTLY_ORDER; > -static unsigned int slub_min_objects; > - > -/* > - * Calculate the order of allocation given an slab object size. > - * > - * The order of allocation has significant impact on performance and other > - * system components. Generally order 0 allocations should be preferred since > - * order 0 does not cause fragmentation in the page allocator. Larger objects > - * be problematic to put into order 0 slabs because there may be too much > - * unused space left. We go to a higher order if more than 1/16th of the slab > - * would be wasted. > - * > - * In order to reach satisfactory performance we must ensure that a minimum > - * number of objects is in one slab. Otherwise we may generate too much > - * activity on the partial lists which requires taking the list_lock. This is > - * less a concern for large slabs though which are rarely used. > - * > - * slub_max_order specifies the order where we begin to stop considering the > - * number of objects in a slab as critical. If we reach slub_max_order then > - * we try to keep the page order as low as possible. So we accept more waste > - * of space in favor of a small page order. > - * > - * Higher order allocations also allow the placement of more objects in a > - * slab and thereby reduce object handling overhead. If the user has > - * requested a higher minimum order then we start with that one instead of > - * the smallest order which will fit the object. > - */ > -static inline unsigned int calc_slab_order(unsigned int size, > - unsigned int min_objects, unsigned int max_order, > - unsigned int fract_leftover) > -{ > - unsigned int min_order = slub_min_order; > - unsigned int order; > - > - if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE) > - return get_order(size * MAX_OBJS_PER_PAGE) - 1; > - > - for (order = max(min_order, (unsigned int)get_order(min_objects * size)); > - order <= max_order; order++) { > - > - unsigned int slab_size = (unsigned int)PAGE_SIZE << order; > - unsigned int rem; > - > - rem = slab_size % size; > - > - if (rem <= slab_size / fract_leftover) > - break; > - } > - > - return order; > -} > - > -static inline int calculate_order(unsigned int size) > -{ > - unsigned int order; > - unsigned int min_objects; > - unsigned int max_objects; > - unsigned int nr_cpus; > - > - /* > - * Attempt to find best configuration for a slab. This > - * works by first attempting to generate a layout with > - * the best configuration and backing off gradually. > - * > - * First we increase the acceptable waste in a slab. Then > - * we reduce the minimum objects required in a slab. > - */ > - min_objects = slub_min_objects; > - if (!min_objects) { > - /* > - * Some architectures will only update present cpus when > - * onlining them, so don't trust the number if it's just 1. But > - * we also don't want to use nr_cpu_ids always, as on some other > - * architectures, there can be many possible cpus, but never > - * onlined. Here we compromise between trying to avoid too high > - * order on systems that appear larger than they are, and too > - * low order on systems that appear smaller than they are. > - */ > - nr_cpus = num_present_cpus(); > - if (nr_cpus <= 1) > - nr_cpus = nr_cpu_ids; > - min_objects = 4 * (fls(nr_cpus) + 1); > - } > - max_objects = order_objects(slub_max_order, size); > - min_objects = min(min_objects, max_objects); > - > - while (min_objects > 1) { > - unsigned int fraction; > - > - fraction = 16; > - while (fraction >= 4) { > - order = calc_slab_order(size, min_objects, > - slub_max_order, fraction); > - if (order <= slub_max_order) > - return order; > - fraction /= 2; > - } > - min_objects--; > - } > - > - /* > - * We were unable to place multiple objects in a slab. Now > - * lets see if we can place a single object there. > - */ > - order = calc_slab_order(size, 1, slub_max_order, 1); > - if (order <= slub_max_order) > - return order; > - > - /* > - * Doh this slab cannot be placed using slub_max_order. > - */ > - order = calc_slab_order(size, 1, MAX_ORDER, 1); > - if (order < MAX_ORDER) > - return order; > - return -ENOSYS; > -} > - > -static void > -init_kmem_cache_node(struct kmem_cache_node *n) > -{ > - n->nr_partial = 0; > - spin_lock_init(&n->list_lock); > - INIT_LIST_HEAD(&n->partial); > -#ifdef CONFIG_SLUB_DEBUG > - atomic_long_set(&n->nr_slabs, 0); > - atomic_long_set(&n->total_objects, 0); > - INIT_LIST_HEAD(&n->full); > -#endif > -} > - > -#ifndef CONFIG_SLUB_TINY > -static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) > -{ > - BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE < > - NR_KMALLOC_TYPES * KMALLOC_SHIFT_HIGH * > - sizeof(struct kmem_cache_cpu)); > - > - /* > - * Must align to double word boundary for the double cmpxchg > - * instructions to work; see __pcpu_double_call_return_bool(). > - */ > - s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu), > - 2 * sizeof(void *)); > - > - if (!s->cpu_slab) > - return 0; > - > - init_kmem_cache_cpus(s); > - > - return 1; > -} > -#else > -static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) > -{ > - return 1; > -} > -#endif /* CONFIG_SLUB_TINY */ > - > -static struct kmem_cache *kmem_cache_node; > - > -/* > - * No kmalloc_node yet so do it by hand. We know that this is the first > - * slab on the node for this slabcache. There are no concurrent accesses > - * possible. > - * > - * Note that this function only works on the kmem_cache_node > - * when allocating for the kmem_cache_node. This is used for bootstrapping > - * memory on a fresh node that has no slab structures yet. > - */ > -static void early_kmem_cache_node_alloc(int node) > -{ > - struct slab *slab; > - struct kmem_cache_node *n; > - > - BUG_ON(kmem_cache_node->size < sizeof(struct kmem_cache_node)); > - > - slab = new_slab(kmem_cache_node, GFP_NOWAIT, node); > - > - BUG_ON(!slab); > - inc_slabs_node(kmem_cache_node, slab_nid(slab), slab->objects); > - if (slab_nid(slab) != node) { > - pr_err("SLUB: Unable to allocate memory from node %d\n", node); > - pr_err("SLUB: Allocating a useless per node structure in order to be able to continue\n"); > - } > - > - n = slab->freelist; > - BUG_ON(!n); > -#ifdef CONFIG_SLUB_DEBUG > - init_object(kmem_cache_node, n, SLUB_RED_ACTIVE); > - init_tracking(kmem_cache_node, n); > -#endif > - n = kasan_slab_alloc(kmem_cache_node, n, GFP_KERNEL, false); > - slab->freelist = get_freepointer(kmem_cache_node, n); > - slab->inuse = 1; > - kmem_cache_node->node[node] = n; > - init_kmem_cache_node(n); > - inc_slabs_node(kmem_cache_node, node, slab->objects); > - > - /* > - * No locks need to be taken here as it has just been > - * initialized and there is no concurrent access. > - */ > - __add_partial(n, slab, DEACTIVATE_TO_HEAD); > -} > - > -static void free_kmem_cache_nodes(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - s->node[node] = NULL; > - kmem_cache_free(kmem_cache_node, n); > - } > -} > - > -void __kmem_cache_release(struct kmem_cache *s) > -{ > - cache_random_seq_destroy(s); > -#ifndef CONFIG_SLUB_TINY > - free_percpu(s->cpu_slab); > -#endif > - free_kmem_cache_nodes(s); > -} > - > -static int init_kmem_cache_nodes(struct kmem_cache *s) > -{ > - int node; > - > - for_each_node_mask(node, slab_nodes) { > - struct kmem_cache_node *n; > - > - if (slab_state == DOWN) { > - early_kmem_cache_node_alloc(node); > - continue; > - } > - n = kmem_cache_alloc_node(kmem_cache_node, > - GFP_KERNEL, node); > - > - if (!n) { > - free_kmem_cache_nodes(s); > - return 0; > - } > - > - init_kmem_cache_node(n); > - s->node[node] = n; > - } > - return 1; > -} > - > -static void set_cpu_partial(struct kmem_cache *s) > -{ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - unsigned int nr_objects; > - > - /* > - * cpu_partial determined the maximum number of objects kept in the > - * per cpu partial lists of a processor. > - * > - * Per cpu partial lists mainly contain slabs that just have one > - * object freed. If they are used for allocation then they can be > - * filled up again with minimal effort. The slab will never hit the > - * per node partial lists and therefore no locking will be required. > - * > - * For backwards compatibility reasons, this is determined as number > - * of objects, even though we now limit maximum number of pages, see > - * slub_set_cpu_partial() > - */ > - if (!kmem_cache_has_cpu_partial(s)) > - nr_objects = 0; > - else if (s->size >= PAGE_SIZE) > - nr_objects = 6; > - else if (s->size >= 1024) > - nr_objects = 24; > - else if (s->size >= 256) > - nr_objects = 52; > - else > - nr_objects = 120; > - > - slub_set_cpu_partial(s, nr_objects); > -#endif > -} > - > -/* > - * calculate_sizes() determines the order and the distribution of data within > - * a slab object. > - */ > -static int calculate_sizes(struct kmem_cache *s) > -{ > - slab_flags_t flags = s->flags; > - unsigned int size = s->object_size; > - unsigned int order; > - > - /* > - * Round up object size to the next word boundary. We can only > - * place the free pointer at word boundaries and this determines > - * the possible location of the free pointer. > - */ > - size = ALIGN(size, sizeof(void *)); > - > -#ifdef CONFIG_SLUB_DEBUG > - /* > - * Determine if we can poison the object itself. If the user of > - * the slab may touch the object after free or before allocation > - * then we should never poison the object itself. > - */ > - if ((flags & SLAB_POISON) && !(flags & SLAB_TYPESAFE_BY_RCU) && > - !s->ctor) > - s->flags |= __OBJECT_POISON; > - else > - s->flags &= ~__OBJECT_POISON; > - > - > - /* > - * If we are Redzoning then check if there is some space between the > - * end of the object and the free pointer. If not then add an > - * additional word to have some bytes to store Redzone information. > - */ > - if ((flags & SLAB_RED_ZONE) && size == s->object_size) > - size += sizeof(void *); > -#endif > - > - /* > - * With that we have determined the number of bytes in actual use > - * by the object and redzoning. > - */ > - s->inuse = size; > - > - if (slub_debug_orig_size(s) || > - (flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) || > - ((flags & SLAB_RED_ZONE) && s->object_size < sizeof(void *)) || > - s->ctor) { > - /* > - * Relocate free pointer after the object if it is not > - * permitted to overwrite the first word of the object on > - * kmem_cache_free. > - * > - * This is the case if we do RCU, have a constructor or > - * destructor, are poisoning the objects, or are > - * redzoning an object smaller than sizeof(void *). > - * > - * The assumption that s->offset >= s->inuse means free > - * pointer is outside of the object is used in the > - * freeptr_outside_object() function. If that is no > - * longer true, the function needs to be modified. > - */ > - s->offset = size; > - size += sizeof(void *); > - } else { > - /* > - * Store freelist pointer near middle of object to keep > - * it away from the edges of the object to avoid small > - * sized over/underflows from neighboring allocations. > - */ > - s->offset = ALIGN_DOWN(s->object_size / 2, sizeof(void *)); > - } > - > -#ifdef CONFIG_SLUB_DEBUG > - if (flags & SLAB_STORE_USER) { > - /* > - * Need to store information about allocs and frees after > - * the object. > - */ > - size += 2 * sizeof(struct track); > - > - /* Save the original kmalloc request size */ > - if (flags & SLAB_KMALLOC) > - size += sizeof(unsigned int); > - } > -#endif > - > - kasan_cache_create(s, &size, &s->flags); > -#ifdef CONFIG_SLUB_DEBUG > - if (flags & SLAB_RED_ZONE) { > - /* > - * Add some empty padding so that we can catch > - * overwrites from earlier objects rather than let > - * tracking information or the free pointer be > - * corrupted if a user writes before the start > - * of the object. > - */ > - size += sizeof(void *); > - > - s->red_left_pad = sizeof(void *); > - s->red_left_pad = ALIGN(s->red_left_pad, s->align); > - size += s->red_left_pad; > - } > -#endif > - > - /* > - * SLUB stores one object immediately after another beginning from > - * offset 0. In order to align the objects we have to simply size > - * each object to conform to the alignment. > - */ > - size = ALIGN(size, s->align); > - s->size = size; > - s->reciprocal_size = reciprocal_value(size); > - order = calculate_order(size); > - > - if ((int)order < 0) > - return 0; > - > - s->allocflags = 0; > - if (order) > - s->allocflags |= __GFP_COMP; > - > - if (s->flags & SLAB_CACHE_DMA) > - s->allocflags |= GFP_DMA; > - > - if (s->flags & SLAB_CACHE_DMA32) > - s->allocflags |= GFP_DMA32; > - > - if (s->flags & SLAB_RECLAIM_ACCOUNT) > - s->allocflags |= __GFP_RECLAIMABLE; > - > - /* > - * Determine the number of objects per slab > - */ > - s->oo = oo_make(order, size); > - s->min = oo_make(get_order(size), size); > - > - return !!oo_objects(s->oo); > -} > - > -static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags) > -{ > - s->flags = kmem_cache_flags(s->size, flags, s->name); > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - s->random = get_random_long(); > -#endif > - > - if (!calculate_sizes(s)) > - goto error; > - if (disable_higher_order_debug) { > - /* > - * Disable debugging flags that store metadata if the min slab > - * order increased. > - */ > - if (get_order(s->size) > get_order(s->object_size)) { > - s->flags &= ~DEBUG_METADATA_FLAGS; > - s->offset = 0; > - if (!calculate_sizes(s)) > - goto error; > - } > - } > - > -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ > - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) > - if (system_has_cmpxchg_double() && (s->flags & SLAB_NO_CMPXCHG) == 0) > - /* Enable fast mode */ > - s->flags |= __CMPXCHG_DOUBLE; > -#endif > - > - /* > - * The larger the object size is, the more slabs we want on the partial > - * list to avoid pounding the page allocator excessively. > - */ > - s->min_partial = min_t(unsigned long, MAX_PARTIAL, ilog2(s->size) / 2); > - s->min_partial = max_t(unsigned long, MIN_PARTIAL, s->min_partial); > - > - set_cpu_partial(s); > - > -#ifdef CONFIG_NUMA > - s->remote_node_defrag_ratio = 1000; > -#endif > - > - /* Initialize the pre-computed randomized freelist if slab is up */ > - if (slab_state >= UP) { > - if (init_cache_random_seq(s)) > - goto error; > - } > - > - if (!init_kmem_cache_nodes(s)) > - goto error; > - > - if (alloc_kmem_cache_cpus(s)) > - return 0; > - > -error: > - __kmem_cache_release(s); > - return -EINVAL; > -} > - > -static void list_slab_objects(struct kmem_cache *s, struct slab *slab, > - const char *text) > -{ > -#ifdef CONFIG_SLUB_DEBUG > - void *addr = slab_address(slab); > - void *p; > - > - slab_err(s, slab, text, s->name); > - > - spin_lock(&object_map_lock); > - __fill_map(object_map, s, slab); > - > - for_each_object(p, s, addr, slab->objects) { > - > - if (!test_bit(__obj_to_index(s, addr, p), object_map)) { > - pr_err("Object 0x%p @offset=%tu\n", p, p - addr); > - print_tracking(s, p); > - } > - } > - spin_unlock(&object_map_lock); > -#endif > -} > - > -/* > - * Attempt to free all partial slabs on a node. > - * This is called from __kmem_cache_shutdown(). We must take list_lock > - * because sysfs file might still access partial list after the shutdowning. > - */ > -static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n) > -{ > - LIST_HEAD(discard); > - struct slab *slab, *h; > - > - BUG_ON(irqs_disabled()); > - spin_lock_irq(&n->list_lock); > - list_for_each_entry_safe(slab, h, &n->partial, slab_list) { > - if (!slab->inuse) { > - remove_partial(n, slab); > - list_add(&slab->slab_list, &discard); > - } else { > - list_slab_objects(s, slab, > - "Objects remaining in %s on __kmem_cache_shutdown()"); > - } > - } > - spin_unlock_irq(&n->list_lock); > - > - list_for_each_entry_safe(slab, h, &discard, slab_list) > - discard_slab(s, slab); > -} > - > -bool __kmem_cache_empty(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) > - if (n->nr_partial || slabs_node(s, node)) > - return false; > - return true; > -} > - > -/* > - * Release all resources used by a slab cache. > - */ > -int __kmem_cache_shutdown(struct kmem_cache *s) > -{ > - int node; > - struct kmem_cache_node *n; > - > - flush_all_cpus_locked(s); > - /* Attempt to free all objects */ > - for_each_kmem_cache_node(s, node, n) { > - free_partial(s, n); > - if (n->nr_partial || slabs_node(s, node)) > - return 1; > - } > - return 0; > -} > - > -#ifdef CONFIG_PRINTK > -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) > -{ > - void *base; > - int __maybe_unused i; > - unsigned int objnr; > - void *objp; > - void *objp0; > - struct kmem_cache *s = slab->slab_cache; > - struct track __maybe_unused *trackp; > - > - kpp->kp_ptr = object; > - kpp->kp_slab = slab; > - kpp->kp_slab_cache = s; > - base = slab_address(slab); > - objp0 = kasan_reset_tag(object); > -#ifdef CONFIG_SLUB_DEBUG > - objp = restore_red_left(s, objp0); > -#else > - objp = objp0; > -#endif > - objnr = obj_to_index(s, slab, objp); > - kpp->kp_data_offset = (unsigned long)((char *)objp0 - (char *)objp); > - objp = base + s->size * objnr; > - kpp->kp_objp = objp; > - if (WARN_ON_ONCE(objp < base || objp >= base + slab->objects * s->size > - || (objp - base) % s->size) || > - !(s->flags & SLAB_STORE_USER)) > - return; > -#ifdef CONFIG_SLUB_DEBUG > - objp = fixup_red_left(s, objp); > - trackp = get_track(s, objp, TRACK_ALLOC); > - kpp->kp_ret = (void *)trackp->addr; > -#ifdef CONFIG_STACKDEPOT > - { > - depot_stack_handle_t handle; > - unsigned long *entries; > - unsigned int nr_entries; > - > - handle = READ_ONCE(trackp->handle); > - if (handle) { > - nr_entries = stack_depot_fetch(handle, &entries); > - for (i = 0; i < KS_ADDRS_COUNT && i < nr_entries; i++) > - kpp->kp_stack[i] = (void *)entries[i]; > - } > - > - trackp = get_track(s, objp, TRACK_FREE); > - handle = READ_ONCE(trackp->handle); > - if (handle) { > - nr_entries = stack_depot_fetch(handle, &entries); > - for (i = 0; i < KS_ADDRS_COUNT && i < nr_entries; i++) > - kpp->kp_free_stack[i] = (void *)entries[i]; > - } > - } > -#endif > -#endif > -} > -#endif > - > -/******************************************************************** > - * Kmalloc subsystem > - *******************************************************************/ > - > -static int __init setup_slub_min_order(char *str) > -{ > - get_option(&str, (int *)&slub_min_order); > - > - return 1; > -} > - > -__setup("slub_min_order=", setup_slub_min_order); > - > -static int __init setup_slub_max_order(char *str) > -{ > - get_option(&str, (int *)&slub_max_order); > - slub_max_order = min(slub_max_order, (unsigned int)MAX_ORDER - 1); > - > - return 1; > -} > - > -__setup("slub_max_order=", setup_slub_max_order); > - > -static int __init setup_slub_min_objects(char *str) > -{ > - get_option(&str, (int *)&slub_min_objects); > - > - return 1; > -} > - > -__setup("slub_min_objects=", setup_slub_min_objects); > - > -#ifdef CONFIG_HARDENED_USERCOPY > -/* > - * Rejects incorrectly sized objects and objects that are to be copied > - * to/from userspace but do not fall entirely within the containing slab > - * cache's usercopy region. > - * > - * Returns NULL if check passes, otherwise const char * to name of cache > - * to indicate an error. > - */ > -void __check_heap_object(const void *ptr, unsigned long n, > - const struct slab *slab, bool to_user) > -{ > - struct kmem_cache *s; > - unsigned int offset; > - bool is_kfence = is_kfence_address(ptr); > - > - ptr = kasan_reset_tag(ptr); > - > - /* Find object and usable object size. */ > - s = slab->slab_cache; > - > - /* Reject impossible pointers. */ > - if (ptr < slab_address(slab)) > - usercopy_abort("SLUB object not in SLUB page?!", NULL, > - to_user, 0, n); > - > - /* Find offset within object. */ > - if (is_kfence) > - offset = ptr - kfence_object_start(ptr); > - else > - offset = (ptr - slab_address(slab)) % s->size; > - > - /* Adjust for redzone and reject if within the redzone. */ > - if (!is_kfence && kmem_cache_debug_flags(s, SLAB_RED_ZONE)) { > - if (offset < s->red_left_pad) > - usercopy_abort("SLUB object in left red zone", > - s->name, to_user, offset, n); > - offset -= s->red_left_pad; > - } > - > - /* Allow address range falling entirely within usercopy region. */ > - if (offset >= s->useroffset && > - offset - s->useroffset <= s->usersize && > - n <= s->useroffset - offset + s->usersize) > - return; > - > - usercopy_abort("SLUB object", s->name, to_user, offset, n); > -} > -#endif /* CONFIG_HARDENED_USERCOPY */ > - > -#define SHRINK_PROMOTE_MAX 32 > - > -/* > - * kmem_cache_shrink discards empty slabs and promotes the slabs filled > - * up most to the head of the partial lists. New allocations will then > - * fill those up and thus they can be removed from the partial lists. > - * > - * The slabs with the least items are placed last. This results in them > - * being allocated from last increasing the chance that the last objects > - * are freed in them. > - */ > -static int __kmem_cache_do_shrink(struct kmem_cache *s) > -{ > - int node; > - int i; > - struct kmem_cache_node *n; > - struct slab *slab; > - struct slab *t; > - struct list_head discard; > - struct list_head promote[SHRINK_PROMOTE_MAX]; > - unsigned long flags; > - int ret = 0; > - > - for_each_kmem_cache_node(s, node, n) { > - INIT_LIST_HEAD(&discard); > - for (i = 0; i < SHRINK_PROMOTE_MAX; i++) > - INIT_LIST_HEAD(promote + i); > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - /* > - * Build lists of slabs to discard or promote. > - * > - * Note that concurrent frees may occur while we hold the > - * list_lock. slab->inuse here is the upper limit. > - */ > - list_for_each_entry_safe(slab, t, &n->partial, slab_list) { > - int free = slab->objects - slab->inuse; > - > - /* Do not reread slab->inuse */ > - barrier(); > - > - /* We do not keep full slabs on the list */ > - BUG_ON(free <= 0); > - > - if (free == slab->objects) { > - list_move(&slab->slab_list, &discard); > - n->nr_partial--; > - dec_slabs_node(s, node, slab->objects); > - } else if (free <= SHRINK_PROMOTE_MAX) > - list_move(&slab->slab_list, promote + free - 1); > - } > - > - /* > - * Promote the slabs filled up most to the head of the > - * partial list. > - */ > - for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--) > - list_splice(promote + i, &n->partial); > - > - spin_unlock_irqrestore(&n->list_lock, flags); > - > - /* Release empty slabs */ > - list_for_each_entry_safe(slab, t, &discard, slab_list) > - free_slab(s, slab); > - > - if (slabs_node(s, node)) > - ret = 1; > - } > - > - return ret; > -} > - > -int __kmem_cache_shrink(struct kmem_cache *s) > -{ > - flush_all(s); > - return __kmem_cache_do_shrink(s); > -} > - > -static int slab_mem_going_offline_callback(void *arg) > -{ > - struct kmem_cache *s; > - > - mutex_lock(&slab_mutex); > - list_for_each_entry(s, &slab_caches, list) { > - flush_all_cpus_locked(s); > - __kmem_cache_do_shrink(s); > - } > - mutex_unlock(&slab_mutex); > - > - return 0; > -} > - > -static void slab_mem_offline_callback(void *arg) > -{ > - struct memory_notify *marg = arg; > - int offline_node; > - > - offline_node = marg->status_change_nid_normal; > - > - /* > - * If the node still has available memory. we need kmem_cache_node > - * for it yet. > - */ > - if (offline_node < 0) > - return; > - > - mutex_lock(&slab_mutex); > - node_clear(offline_node, slab_nodes); > - /* > - * We no longer free kmem_cache_node structures here, as it would be > - * racy with all get_node() users, and infeasible to protect them with > - * slab_mutex. > - */ > - mutex_unlock(&slab_mutex); > -} > - > -static int slab_mem_going_online_callback(void *arg) > -{ > - struct kmem_cache_node *n; > - struct kmem_cache *s; > - struct memory_notify *marg = arg; > - int nid = marg->status_change_nid_normal; > - int ret = 0; > - > - /* > - * If the node's memory is already available, then kmem_cache_node is > - * already created. Nothing to do. > - */ > - if (nid < 0) > - return 0; > - > - /* > - * We are bringing a node online. No memory is available yet. We must > - * allocate a kmem_cache_node structure in order to bring the node > - * online. > - */ > - mutex_lock(&slab_mutex); > - list_for_each_entry(s, &slab_caches, list) { > - /* > - * The structure may already exist if the node was previously > - * onlined and offlined. > - */ > - if (get_node(s, nid)) > - continue; > - /* > - * XXX: kmem_cache_alloc_node will fallback to other nodes > - * since memory is not yet available from the node that > - * is brought up. > - */ > - n = kmem_cache_alloc(kmem_cache_node, GFP_KERNEL); > - if (!n) { > - ret = -ENOMEM; > - goto out; > - } > - init_kmem_cache_node(n); > - s->node[nid] = n; > - } > - /* > - * Any cache created after this point will also have kmem_cache_node > - * initialized for the new node. > - */ > - node_set(nid, slab_nodes); > -out: > - mutex_unlock(&slab_mutex); > - return ret; > -} > - > -static int slab_memory_callback(struct notifier_block *self, > - unsigned long action, void *arg) > -{ > - int ret = 0; > - > - switch (action) { > - case MEM_GOING_ONLINE: > - ret = slab_mem_going_online_callback(arg); > - break; > - case MEM_GOING_OFFLINE: > - ret = slab_mem_going_offline_callback(arg); > - break; > - case MEM_OFFLINE: > - case MEM_CANCEL_ONLINE: > - slab_mem_offline_callback(arg); > - break; > - case MEM_ONLINE: > - case MEM_CANCEL_OFFLINE: > - break; > - } > - if (ret) > - ret = notifier_from_errno(ret); > - else > - ret = NOTIFY_OK; > - return ret; > -} > - > -/******************************************************************** > - * Basic setup of slabs > - *******************************************************************/ > - > -/* > - * Used for early kmem_cache structures that were allocated using > - * the page allocator. Allocate them properly then fix up the pointers > - * that may be pointing to the wrong kmem_cache structure. > - */ > - > -static struct kmem_cache * __init bootstrap(struct kmem_cache *static_cache) > -{ > - int node; > - struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); > - struct kmem_cache_node *n; > - > - memcpy(s, static_cache, kmem_cache->object_size); > - > - /* > - * This runs very early, and only the boot processor is supposed to be > - * up. Even if it weren't true, IRQs are not up so we couldn't fire > - * IPIs around. > - */ > - __flush_cpu_slab(s, smp_processor_id()); > - for_each_kmem_cache_node(s, node, n) { > - struct slab *p; > - > - list_for_each_entry(p, &n->partial, slab_list) > - p->slab_cache = s; > - > -#ifdef CONFIG_SLUB_DEBUG > - list_for_each_entry(p, &n->full, slab_list) > - p->slab_cache = s; > -#endif > - } > - list_add(&s->list, &slab_caches); > - return s; > -} > - > -void __init kmem_cache_init(void) > -{ > - static __initdata struct kmem_cache boot_kmem_cache, > - boot_kmem_cache_node; > - int node; > - > - if (debug_guardpage_minorder()) > - slub_max_order = 0; > - > - /* Print slub debugging pointers without hashing */ > - if (__slub_debug_enabled()) > - no_hash_pointers_enable(NULL); > - > - kmem_cache_node = &boot_kmem_cache_node; > - kmem_cache = &boot_kmem_cache; > - > - /* > - * Initialize the nodemask for which we will allocate per node > - * structures. Here we don't need taking slab_mutex yet. > - */ > - for_each_node_state(node, N_NORMAL_MEMORY) > - node_set(node, slab_nodes); > - > - create_boot_cache(kmem_cache_node, "kmem_cache_node", > - sizeof(struct kmem_cache_node), SLAB_HWCACHE_ALIGN, 0, 0); > - > - hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI); > - > - /* Able to allocate the per node structures */ > - slab_state = PARTIAL; > - > - create_boot_cache(kmem_cache, "kmem_cache", > - offsetof(struct kmem_cache, node) + > - nr_node_ids * sizeof(struct kmem_cache_node *), > - SLAB_HWCACHE_ALIGN, 0, 0); > - > - kmem_cache = bootstrap(&boot_kmem_cache); > - kmem_cache_node = bootstrap(&boot_kmem_cache_node); > - > - /* Now we can use the kmem_cache to allocate kmalloc slabs */ > - setup_kmalloc_cache_index_table(); > - create_kmalloc_caches(0); > - > - /* Setup random freelists for each cache */ > - init_freelist_randomization(); > - > - cpuhp_setup_state_nocalls(CPUHP_SLUB_DEAD, "slub:dead", NULL, > - slub_cpu_dead); > - > - pr_info("SLUB: HWalign=%d, Order=%u-%u, MinObjects=%u, CPUs=%u, Nodes=%u\n", > - cache_line_size(), > - slub_min_order, slub_max_order, slub_min_objects, > - nr_cpu_ids, nr_node_ids); > -} > - > -void __init kmem_cache_init_late(void) > -{ > -#ifndef CONFIG_SLUB_TINY > - flushwq = alloc_workqueue("slub_flushwq", WQ_MEM_RECLAIM, 0); > - WARN_ON(!flushwq); > -#endif > -} > - > -struct kmem_cache * > -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > - slab_flags_t flags, void (*ctor)(void *)) > -{ > - struct kmem_cache *s; > - > - s = find_mergeable(size, align, flags, name, ctor); > - if (s) { > - if (sysfs_slab_alias(s, name)) > - return NULL; > - > - s->refcount++; > - > - /* > - * Adjust the object sizes so that we clear > - * the complete object on kzalloc. > - */ > - s->object_size = max(s->object_size, size); > - s->inuse = max(s->inuse, ALIGN(size, sizeof(void *))); > - } > - > - return s; > -} > - > -int __kmem_cache_create(struct kmem_cache *s, slab_flags_t flags) > -{ > - int err; > - > - err = kmem_cache_open(s, flags); > - if (err) > - return err; > - > - /* Mutex is not taken during early boot */ > - if (slab_state <= UP) > - return 0; > - > - err = sysfs_slab_add(s); > - if (err) { > - __kmem_cache_release(s); > - return err; > - } > - > - if (s->flags & SLAB_STORE_USER) > - debugfs_slab_add(s); > - > - return 0; > -} > - > -#ifdef SLAB_SUPPORTS_SYSFS > -static int count_inuse(struct slab *slab) > -{ > - return slab->inuse; > -} > - > -static int count_total(struct slab *slab) > -{ > - return slab->objects; > -} > -#endif > - > -#ifdef CONFIG_SLUB_DEBUG > -static void validate_slab(struct kmem_cache *s, struct slab *slab, > - unsigned long *obj_map) > -{ > - void *p; > - void *addr = slab_address(slab); > - > - if (!check_slab(s, slab) || !on_freelist(s, slab, NULL)) > - return; > - > - /* Now we know that a valid freelist exists */ > - __fill_map(obj_map, s, slab); > - for_each_object(p, s, addr, slab->objects) { > - u8 val = test_bit(__obj_to_index(s, addr, p), obj_map) ? > - SLUB_RED_INACTIVE : SLUB_RED_ACTIVE; > - > - if (!check_object(s, slab, p, val)) > - break; > - } > -} > - > -static int validate_slab_node(struct kmem_cache *s, > - struct kmem_cache_node *n, unsigned long *obj_map) > -{ > - unsigned long count = 0; > - struct slab *slab; > - unsigned long flags; > - > - spin_lock_irqsave(&n->list_lock, flags); > - > - list_for_each_entry(slab, &n->partial, slab_list) { > - validate_slab(s, slab, obj_map); > - count++; > - } > - if (count != n->nr_partial) { > - pr_err("SLUB %s: %ld partial slabs counted but counter=%ld\n", > - s->name, count, n->nr_partial); > - slab_add_kunit_errors(); > - } > - > - if (!(s->flags & SLAB_STORE_USER)) > - goto out; > - > - list_for_each_entry(slab, &n->full, slab_list) { > - validate_slab(s, slab, obj_map); > - count++; > - } > - if (count != atomic_long_read(&n->nr_slabs)) { > - pr_err("SLUB: %s %ld slabs counted but counter=%ld\n", > - s->name, count, atomic_long_read(&n->nr_slabs)); > - slab_add_kunit_errors(); > - } > - > -out: > - spin_unlock_irqrestore(&n->list_lock, flags); > - return count; > -} > - > -long validate_slab_cache(struct kmem_cache *s) > -{ > - int node; > - unsigned long count = 0; > - struct kmem_cache_node *n; > - unsigned long *obj_map; > - > - obj_map = bitmap_alloc(oo_objects(s->oo), GFP_KERNEL); > - if (!obj_map) > - return -ENOMEM; > - > - flush_all(s); > - for_each_kmem_cache_node(s, node, n) > - count += validate_slab_node(s, n, obj_map); > - > - bitmap_free(obj_map); > - > - return count; > -} > -EXPORT_SYMBOL(validate_slab_cache); > - > -#ifdef CONFIG_DEBUG_FS > -/* > - * Generate lists of code addresses where slabcache objects are allocated > - * and freed. > - */ > - > -struct location { > - depot_stack_handle_t handle; > - unsigned long count; > - unsigned long addr; > - unsigned long waste; > - long long sum_time; > - long min_time; > - long max_time; > - long min_pid; > - long max_pid; > - DECLARE_BITMAP(cpus, NR_CPUS); > - nodemask_t nodes; > -}; > - > -struct loc_track { > - unsigned long max; > - unsigned long count; > - struct location *loc; > - loff_t idx; > -}; > - > -static struct dentry *slab_debugfs_root; > - > -static void free_loc_track(struct loc_track *t) > -{ > - if (t->max) > - free_pages((unsigned long)t->loc, > - get_order(sizeof(struct location) * t->max)); > -} > - > -static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags) > -{ > - struct location *l; > - int order; > - > - order = get_order(sizeof(struct location) * max); > - > - l = (void *)__get_free_pages(flags, order); > - if (!l) > - return 0; > - > - if (t->count) { > - memcpy(l, t->loc, sizeof(struct location) * t->count); > - free_loc_track(t); > - } > - t->max = max; > - t->loc = l; > - return 1; > -} > - > -static int add_location(struct loc_track *t, struct kmem_cache *s, > - const struct track *track, > - unsigned int orig_size) > -{ > - long start, end, pos; > - struct location *l; > - unsigned long caddr, chandle, cwaste; > - unsigned long age = jiffies - track->when; > - depot_stack_handle_t handle = 0; > - unsigned int waste = s->object_size - orig_size; > - > -#ifdef CONFIG_STACKDEPOT > - handle = READ_ONCE(track->handle); > -#endif > - start = -1; > - end = t->count; > - > - for ( ; ; ) { > - pos = start + (end - start + 1) / 2; > - > - /* > - * There is nothing at "end". If we end up there > - * we need to add something to before end. > - */ > - if (pos == end) > - break; > - > - l = &t->loc[pos]; > - caddr = l->addr; > - chandle = l->handle; > - cwaste = l->waste; > - if ((track->addr == caddr) && (handle == chandle) && > - (waste == cwaste)) { > - > - l->count++; > - if (track->when) { > - l->sum_time += age; > - if (age < l->min_time) > - l->min_time = age; > - if (age > l->max_time) > - l->max_time = age; > - > - if (track->pid < l->min_pid) > - l->min_pid = track->pid; > - if (track->pid > l->max_pid) > - l->max_pid = track->pid; > - > - cpumask_set_cpu(track->cpu, > - to_cpumask(l->cpus)); > - } > - node_set(page_to_nid(virt_to_page(track)), l->nodes); > - return 1; > - } > - > - if (track->addr < caddr) > - end = pos; > - else if (track->addr == caddr && handle < chandle) > - end = pos; > - else if (track->addr == caddr && handle == chandle && > - waste < cwaste) > - end = pos; > - else > - start = pos; > - } > - > - /* > - * Not found. Insert new tracking element. > - */ > - if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC)) > - return 0; > - > - l = t->loc + pos; > - if (pos < t->count) > - memmove(l + 1, l, > - (t->count - pos) * sizeof(struct location)); > - t->count++; > - l->count = 1; > - l->addr = track->addr; > - l->sum_time = age; > - l->min_time = age; > - l->max_time = age; > - l->min_pid = track->pid; > - l->max_pid = track->pid; > - l->handle = handle; > - l->waste = waste; > - cpumask_clear(to_cpumask(l->cpus)); > - cpumask_set_cpu(track->cpu, to_cpumask(l->cpus)); > - nodes_clear(l->nodes); > - node_set(page_to_nid(virt_to_page(track)), l->nodes); > - return 1; > -} > - > -static void process_slab(struct loc_track *t, struct kmem_cache *s, > - struct slab *slab, enum track_item alloc, > - unsigned long *obj_map) > -{ > - void *addr = slab_address(slab); > - bool is_alloc = (alloc == TRACK_ALLOC); > - void *p; > - > - __fill_map(obj_map, s, slab); > - > - for_each_object(p, s, addr, slab->objects) > - if (!test_bit(__obj_to_index(s, addr, p), obj_map)) > - add_location(t, s, get_track(s, p, alloc), > - is_alloc ? get_orig_size(s, p) : > - s->object_size); > -} > -#endif /* CONFIG_DEBUG_FS */ > -#endif /* CONFIG_SLUB_DEBUG */ > - > -#ifdef SLAB_SUPPORTS_SYSFS > -enum slab_stat_type { > - SL_ALL, /* All slabs */ > - SL_PARTIAL, /* Only partially allocated slabs */ > - SL_CPU, /* Only slabs used for cpu caches */ > - SL_OBJECTS, /* Determine allocated objects not slabs */ > - SL_TOTAL /* Determine object capacity not slabs */ > -}; > - > -#define SO_ALL (1 << SL_ALL) > -#define SO_PARTIAL (1 << SL_PARTIAL) > -#define SO_CPU (1 << SL_CPU) > -#define SO_OBJECTS (1 << SL_OBJECTS) > -#define SO_TOTAL (1 << SL_TOTAL) > - > -static ssize_t show_slab_objects(struct kmem_cache *s, > - char *buf, unsigned long flags) > -{ > - unsigned long total = 0; > - int node; > - int x; > - unsigned long *nodes; > - int len = 0; > - > - nodes = kcalloc(nr_node_ids, sizeof(unsigned long), GFP_KERNEL); > - if (!nodes) > - return -ENOMEM; > - > - if (flags & SO_CPU) { > - int cpu; > - > - for_each_possible_cpu(cpu) { > - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, > - cpu); > - int node; > - struct slab *slab; > - > - slab = READ_ONCE(c->slab); > - if (!slab) > - continue; > - > - node = slab_nid(slab); > - if (flags & SO_TOTAL) > - x = slab->objects; > - else if (flags & SO_OBJECTS) > - x = slab->inuse; > - else > - x = 1; > - > - total += x; > - nodes[node] += x; > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - slab = slub_percpu_partial_read_once(c); > - if (slab) { > - node = slab_nid(slab); > - if (flags & SO_TOTAL) > - WARN_ON_ONCE(1); > - else if (flags & SO_OBJECTS) > - WARN_ON_ONCE(1); > - else > - x = slab->slabs; > - total += x; > - nodes[node] += x; > - } > -#endif > - } > - } > - > - /* > - * It is impossible to take "mem_hotplug_lock" here with "kernfs_mutex" > - * already held which will conflict with an existing lock order: > - * > - * mem_hotplug_lock->slab_mutex->kernfs_mutex > - * > - * We don't really need mem_hotplug_lock (to hold off > - * slab_mem_going_offline_callback) here because slab's memory hot > - * unplug code doesn't destroy the kmem_cache->node[] data. > - */ > - > -#ifdef CONFIG_SLUB_DEBUG > - if (flags & SO_ALL) { > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - > - if (flags & SO_TOTAL) > - x = atomic_long_read(&n->total_objects); > - else if (flags & SO_OBJECTS) > - x = atomic_long_read(&n->total_objects) - > - count_partial(n, count_free); > - else > - x = atomic_long_read(&n->nr_slabs); > - total += x; > - nodes[node] += x; > - } > - > - } else > -#endif > - if (flags & SO_PARTIAL) { > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - if (flags & SO_TOTAL) > - x = count_partial(n, count_total); > - else if (flags & SO_OBJECTS) > - x = count_partial(n, count_inuse); > - else > - x = n->nr_partial; > - total += x; > - nodes[node] += x; > - } > - } > - > - len += sysfs_emit_at(buf, len, "%lu", total); > -#ifdef CONFIG_NUMA > - for (node = 0; node < nr_node_ids; node++) { > - if (nodes[node]) > - len += sysfs_emit_at(buf, len, " N%d=%lu", > - node, nodes[node]); > - } > -#endif > - len += sysfs_emit_at(buf, len, "\n"); > - kfree(nodes); > - > - return len; > -} > - > -#define to_slab_attr(n) container_of(n, struct slab_attribute, attr) > -#define to_slab(n) container_of(n, struct kmem_cache, kobj) > - > -struct slab_attribute { > - struct attribute attr; > - ssize_t (*show)(struct kmem_cache *s, char *buf); > - ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count); > -}; > - > -#define SLAB_ATTR_RO(_name) \ > - static struct slab_attribute _name##_attr = __ATTR_RO_MODE(_name, 0400) > - > -#define SLAB_ATTR(_name) \ > - static struct slab_attribute _name##_attr = __ATTR_RW_MODE(_name, 0600) > - > -static ssize_t slab_size_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->size); > -} > -SLAB_ATTR_RO(slab_size); > - > -static ssize_t align_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->align); > -} > -SLAB_ATTR_RO(align); > - > -static ssize_t object_size_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->object_size); > -} > -SLAB_ATTR_RO(object_size); > - > -static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", oo_objects(s->oo)); > -} > -SLAB_ATTR_RO(objs_per_slab); > - > -static ssize_t order_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", oo_order(s->oo)); > -} > -SLAB_ATTR_RO(order); > - > -static ssize_t min_partial_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%lu\n", s->min_partial); > -} > - > -static ssize_t min_partial_store(struct kmem_cache *s, const char *buf, > - size_t length) > -{ > - unsigned long min; > - int err; > - > - err = kstrtoul(buf, 10, &min); > - if (err) > - return err; > - > - s->min_partial = min; > - return length; > -} > -SLAB_ATTR(min_partial); > - > -static ssize_t cpu_partial_show(struct kmem_cache *s, char *buf) > -{ > - unsigned int nr_partial = 0; > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - nr_partial = s->cpu_partial; > -#endif > - > - return sysfs_emit(buf, "%u\n", nr_partial); > -} > - > -static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf, > - size_t length) > -{ > - unsigned int objects; > - int err; > - > - err = kstrtouint(buf, 10, &objects); > - if (err) > - return err; > - if (objects && !kmem_cache_has_cpu_partial(s)) > - return -EINVAL; > - > - slub_set_cpu_partial(s, objects); > - flush_all(s); > - return length; > -} > -SLAB_ATTR(cpu_partial); > - > -static ssize_t ctor_show(struct kmem_cache *s, char *buf) > -{ > - if (!s->ctor) > - return 0; > - return sysfs_emit(buf, "%pS\n", s->ctor); > -} > -SLAB_ATTR_RO(ctor); > - > -static ssize_t aliases_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", s->refcount < 0 ? 0 : s->refcount - 1); > -} > -SLAB_ATTR_RO(aliases); > - > -static ssize_t partial_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_PARTIAL); > -} > -SLAB_ATTR_RO(partial); > - > -static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_CPU); > -} > -SLAB_ATTR_RO(cpu_slabs); > - > -static ssize_t objects_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS); > -} > -SLAB_ATTR_RO(objects); > - > -static ssize_t objects_partial_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS); > -} > -SLAB_ATTR_RO(objects_partial); > - > -static ssize_t slabs_cpu_partial_show(struct kmem_cache *s, char *buf) > -{ > - int objects = 0; > - int slabs = 0; > - int cpu __maybe_unused; > - int len = 0; > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - for_each_online_cpu(cpu) { > - struct slab *slab; > - > - slab = slub_percpu_partial(per_cpu_ptr(s->cpu_slab, cpu)); > - > - if (slab) > - slabs += slab->slabs; > - } > -#endif > - > - /* Approximate half-full slabs, see slub_set_cpu_partial() */ > - objects = (slabs * oo_objects(s->oo)) / 2; > - len += sysfs_emit_at(buf, len, "%d(%d)", objects, slabs); > - > -#if defined(CONFIG_SLUB_CPU_PARTIAL) && defined(CONFIG_SMP) > - for_each_online_cpu(cpu) { > - struct slab *slab; > - > - slab = slub_percpu_partial(per_cpu_ptr(s->cpu_slab, cpu)); > - if (slab) { > - slabs = READ_ONCE(slab->slabs); > - objects = (slabs * oo_objects(s->oo)) / 2; > - len += sysfs_emit_at(buf, len, " C%d=%d(%d)", > - cpu, objects, slabs); > - } > - } > -#endif > - len += sysfs_emit_at(buf, len, "\n"); > - > - return len; > -} > -SLAB_ATTR_RO(slabs_cpu_partial); > - > -static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT)); > -} > -SLAB_ATTR_RO(reclaim_account); > - > -static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN)); > -} > -SLAB_ATTR_RO(hwcache_align); > - > -#ifdef CONFIG_ZONE_DMA > -static ssize_t cache_dma_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA)); > -} > -SLAB_ATTR_RO(cache_dma); > -#endif > - > -#ifdef CONFIG_HARDENED_USERCOPY > -static ssize_t usersize_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->usersize); > -} > -SLAB_ATTR_RO(usersize); > -#endif > - > -static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_TYPESAFE_BY_RCU)); > -} > -SLAB_ATTR_RO(destroy_by_rcu); > - > -#ifdef CONFIG_SLUB_DEBUG > -static ssize_t slabs_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_ALL); > -} > -SLAB_ATTR_RO(slabs); > - > -static ssize_t total_objects_show(struct kmem_cache *s, char *buf) > -{ > - return show_slab_objects(s, buf, SO_ALL|SO_TOTAL); > -} > -SLAB_ATTR_RO(total_objects); > - > -static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_CONSISTENCY_CHECKS)); > -} > -SLAB_ATTR_RO(sanity_checks); > - > -static ssize_t trace_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_TRACE)); > -} > -SLAB_ATTR_RO(trace); > - > -static ssize_t red_zone_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE)); > -} > - > -SLAB_ATTR_RO(red_zone); > - > -static ssize_t poison_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_POISON)); > -} > - > -SLAB_ATTR_RO(poison); > - > -static ssize_t store_user_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_STORE_USER)); > -} > - > -SLAB_ATTR_RO(store_user); > - > -static ssize_t validate_show(struct kmem_cache *s, char *buf) > -{ > - return 0; > -} > - > -static ssize_t validate_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - int ret = -EINVAL; > - > - if (buf[0] == '1' && kmem_cache_debug(s)) { > - ret = validate_slab_cache(s); > - if (ret >= 0) > - ret = length; > - } > - return ret; > -} > -SLAB_ATTR(validate); > - > -#endif /* CONFIG_SLUB_DEBUG */ > - > -#ifdef CONFIG_FAILSLAB > -static ssize_t failslab_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB)); > -} > - > -static ssize_t failslab_store(struct kmem_cache *s, const char *buf, > - size_t length) > -{ > - if (s->refcount > 1) > - return -EINVAL; > - > - if (buf[0] == '1') > - WRITE_ONCE(s->flags, s->flags | SLAB_FAILSLAB); > - else > - WRITE_ONCE(s->flags, s->flags & ~SLAB_FAILSLAB); > - > - return length; > -} > -SLAB_ATTR(failslab); > -#endif > - > -static ssize_t shrink_show(struct kmem_cache *s, char *buf) > -{ > - return 0; > -} > - > -static ssize_t shrink_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - if (buf[0] == '1') > - kmem_cache_shrink(s); > - else > - return -EINVAL; > - return length; > -} > -SLAB_ATTR(shrink); > - > -#ifdef CONFIG_NUMA > -static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%u\n", s->remote_node_defrag_ratio / 10); > -} > - > -static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - unsigned int ratio; > - int err; > - > - err = kstrtouint(buf, 10, &ratio); > - if (err) > - return err; > - if (ratio > 100) > - return -ERANGE; > - > - s->remote_node_defrag_ratio = ratio * 10; > - > - return length; > -} > -SLAB_ATTR(remote_node_defrag_ratio); > -#endif > - > -#ifdef CONFIG_SLUB_STATS > -static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si) > -{ > - unsigned long sum = 0; > - int cpu; > - int len = 0; > - int *data = kmalloc_array(nr_cpu_ids, sizeof(int), GFP_KERNEL); > - > - if (!data) > - return -ENOMEM; > - > - for_each_online_cpu(cpu) { > - unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si]; > - > - data[cpu] = x; > - sum += x; > - } > - > - len += sysfs_emit_at(buf, len, "%lu", sum); > - > -#ifdef CONFIG_SMP > - for_each_online_cpu(cpu) { > - if (data[cpu]) > - len += sysfs_emit_at(buf, len, " C%d=%u", > - cpu, data[cpu]); > - } > -#endif > - kfree(data); > - len += sysfs_emit_at(buf, len, "\n"); > - > - return len; > -} > - > -static void clear_stat(struct kmem_cache *s, enum stat_item si) > -{ > - int cpu; > - > - for_each_online_cpu(cpu) > - per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0; > -} > - > -#define STAT_ATTR(si, text) \ > -static ssize_t text##_show(struct kmem_cache *s, char *buf) \ > -{ \ > - return show_stat(s, buf, si); \ > -} \ > -static ssize_t text##_store(struct kmem_cache *s, \ > - const char *buf, size_t length) \ > -{ \ > - if (buf[0] != '0') \ > - return -EINVAL; \ > - clear_stat(s, si); \ > - return length; \ > -} \ > -SLAB_ATTR(text); \ > - > -STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath); > -STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath); > -STAT_ATTR(FREE_FASTPATH, free_fastpath); > -STAT_ATTR(FREE_SLOWPATH, free_slowpath); > -STAT_ATTR(FREE_FROZEN, free_frozen); > -STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial); > -STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial); > -STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial); > -STAT_ATTR(ALLOC_SLAB, alloc_slab); > -STAT_ATTR(ALLOC_REFILL, alloc_refill); > -STAT_ATTR(ALLOC_NODE_MISMATCH, alloc_node_mismatch); > -STAT_ATTR(FREE_SLAB, free_slab); > -STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush); > -STAT_ATTR(DEACTIVATE_FULL, deactivate_full); > -STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty); > -STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head); > -STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail); > -STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees); > -STAT_ATTR(DEACTIVATE_BYPASS, deactivate_bypass); > -STAT_ATTR(ORDER_FALLBACK, order_fallback); > -STAT_ATTR(CMPXCHG_DOUBLE_CPU_FAIL, cmpxchg_double_cpu_fail); > -STAT_ATTR(CMPXCHG_DOUBLE_FAIL, cmpxchg_double_fail); > -STAT_ATTR(CPU_PARTIAL_ALLOC, cpu_partial_alloc); > -STAT_ATTR(CPU_PARTIAL_FREE, cpu_partial_free); > -STAT_ATTR(CPU_PARTIAL_NODE, cpu_partial_node); > -STAT_ATTR(CPU_PARTIAL_DRAIN, cpu_partial_drain); > -#endif /* CONFIG_SLUB_STATS */ > - > -#ifdef CONFIG_KFENCE > -static ssize_t skip_kfence_show(struct kmem_cache *s, char *buf) > -{ > - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_SKIP_KFENCE)); > -} > - > -static ssize_t skip_kfence_store(struct kmem_cache *s, > - const char *buf, size_t length) > -{ > - int ret = length; > - > - if (buf[0] == '0') > - s->flags &= ~SLAB_SKIP_KFENCE; > - else if (buf[0] == '1') > - s->flags |= SLAB_SKIP_KFENCE; > - else > - ret = -EINVAL; > - > - return ret; > -} > -SLAB_ATTR(skip_kfence); > -#endif > - > -static struct attribute *slab_attrs[] = { > - &slab_size_attr.attr, > - &object_size_attr.attr, > - &objs_per_slab_attr.attr, > - &order_attr.attr, > - &min_partial_attr.attr, > - &cpu_partial_attr.attr, > - &objects_attr.attr, > - &objects_partial_attr.attr, > - &partial_attr.attr, > - &cpu_slabs_attr.attr, > - &ctor_attr.attr, > - &aliases_attr.attr, > - &align_attr.attr, > - &hwcache_align_attr.attr, > - &reclaim_account_attr.attr, > - &destroy_by_rcu_attr.attr, > - &shrink_attr.attr, > - &slabs_cpu_partial_attr.attr, > -#ifdef CONFIG_SLUB_DEBUG > - &total_objects_attr.attr, > - &slabs_attr.attr, > - &sanity_checks_attr.attr, > - &trace_attr.attr, > - &red_zone_attr.attr, > - &poison_attr.attr, > - &store_user_attr.attr, > - &validate_attr.attr, > -#endif > -#ifdef CONFIG_ZONE_DMA > - &cache_dma_attr.attr, > -#endif > -#ifdef CONFIG_NUMA > - &remote_node_defrag_ratio_attr.attr, > -#endif > -#ifdef CONFIG_SLUB_STATS > - &alloc_fastpath_attr.attr, > - &alloc_slowpath_attr.attr, > - &free_fastpath_attr.attr, > - &free_slowpath_attr.attr, > - &free_frozen_attr.attr, > - &free_add_partial_attr.attr, > - &free_remove_partial_attr.attr, > - &alloc_from_partial_attr.attr, > - &alloc_slab_attr.attr, > - &alloc_refill_attr.attr, > - &alloc_node_mismatch_attr.attr, > - &free_slab_attr.attr, > - &cpuslab_flush_attr.attr, > - &deactivate_full_attr.attr, > - &deactivate_empty_attr.attr, > - &deactivate_to_head_attr.attr, > - &deactivate_to_tail_attr.attr, > - &deactivate_remote_frees_attr.attr, > - &deactivate_bypass_attr.attr, > - &order_fallback_attr.attr, > - &cmpxchg_double_fail_attr.attr, > - &cmpxchg_double_cpu_fail_attr.attr, > - &cpu_partial_alloc_attr.attr, > - &cpu_partial_free_attr.attr, > - &cpu_partial_node_attr.attr, > - &cpu_partial_drain_attr.attr, > -#endif > -#ifdef CONFIG_FAILSLAB > - &failslab_attr.attr, > -#endif > -#ifdef CONFIG_HARDENED_USERCOPY > - &usersize_attr.attr, > -#endif > -#ifdef CONFIG_KFENCE > - &skip_kfence_attr.attr, > -#endif > - > - NULL > -}; > - > -static const struct attribute_group slab_attr_group = { > - .attrs = slab_attrs, > -}; > - > -static ssize_t slab_attr_show(struct kobject *kobj, > - struct attribute *attr, > - char *buf) > -{ > - struct slab_attribute *attribute; > - struct kmem_cache *s; > - > - attribute = to_slab_attr(attr); > - s = to_slab(kobj); > - > - if (!attribute->show) > - return -EIO; > - > - return attribute->show(s, buf); > -} > - > -static ssize_t slab_attr_store(struct kobject *kobj, > - struct attribute *attr, > - const char *buf, size_t len) > -{ > - struct slab_attribute *attribute; > - struct kmem_cache *s; > - > - attribute = to_slab_attr(attr); > - s = to_slab(kobj); > - > - if (!attribute->store) > - return -EIO; > - > - return attribute->store(s, buf, len); > -} > - > -static void kmem_cache_release(struct kobject *k) > -{ > - slab_kmem_cache_release(to_slab(k)); > -} > - > -static const struct sysfs_ops slab_sysfs_ops = { > - .show = slab_attr_show, > - .store = slab_attr_store, > -}; > - > -static struct kobj_type slab_ktype = { > - .sysfs_ops = &slab_sysfs_ops, > - .release = kmem_cache_release, > -}; > - > -static struct kset *slab_kset; > - > -static inline struct kset *cache_kset(struct kmem_cache *s) > -{ > - return slab_kset; > -} > - > -#define ID_STR_LENGTH 32 > - > -/* Create a unique string id for a slab cache: > - * > - * Format :[flags-]size > - */ > -static char *create_unique_id(struct kmem_cache *s) > -{ > - char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL); > - char *p = name; > - > - if (!name) > - return ERR_PTR(-ENOMEM); > - > - *p++ = ':'; > - /* > - * First flags affecting slabcache operations. We will only > - * get here for aliasable slabs so we do not need to support > - * too many flags. The flags here must cover all flags that > - * are matched during merging to guarantee that the id is > - * unique. > - */ > - if (s->flags & SLAB_CACHE_DMA) > - *p++ = 'd'; > - if (s->flags & SLAB_CACHE_DMA32) > - *p++ = 'D'; > - if (s->flags & SLAB_RECLAIM_ACCOUNT) > - *p++ = 'a'; > - if (s->flags & SLAB_CONSISTENCY_CHECKS) > - *p++ = 'F'; > - if (s->flags & SLAB_ACCOUNT) > - *p++ = 'A'; > - if (p != name + 1) > - *p++ = '-'; > - p += snprintf(p, ID_STR_LENGTH - (p - name), "%07u", s->size); > - > - if (WARN_ON(p > name + ID_STR_LENGTH - 1)) { > - kfree(name); > - return ERR_PTR(-EINVAL); > - } > - kmsan_unpoison_memory(name, p - name); > - return name; > -} > - > -static int sysfs_slab_add(struct kmem_cache *s) > -{ > - int err; > - const char *name; > - struct kset *kset = cache_kset(s); > - int unmergeable = slab_unmergeable(s); > - > - if (!unmergeable && disable_higher_order_debug && > - (slub_debug & DEBUG_METADATA_FLAGS)) > - unmergeable = 1; > - > - if (unmergeable) { > - /* > - * Slabcache can never be merged so we can use the name proper. > - * This is typically the case for debug situations. In that > - * case we can catch duplicate names easily. > - */ > - sysfs_remove_link(&slab_kset->kobj, s->name); > - name = s->name; > - } else { > - /* > - * Create a unique name for the slab as a target > - * for the symlinks. > - */ > - name = create_unique_id(s); > - if (IS_ERR(name)) > - return PTR_ERR(name); > - } > - > - s->kobj.kset = kset; > - err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, "%s", name); > - if (err) > - goto out; > - > - err = sysfs_create_group(&s->kobj, &slab_attr_group); > - if (err) > - goto out_del_kobj; > - > - if (!unmergeable) { > - /* Setup first alias */ > - sysfs_slab_alias(s, s->name); > - } > -out: > - if (!unmergeable) > - kfree(name); > - return err; > -out_del_kobj: > - kobject_del(&s->kobj); > - goto out; > -} > - > -void sysfs_slab_unlink(struct kmem_cache *s) > -{ > - if (slab_state >= FULL) > - kobject_del(&s->kobj); > -} > - > -void sysfs_slab_release(struct kmem_cache *s) > -{ > - if (slab_state >= FULL) > - kobject_put(&s->kobj); > -} > - > -/* > - * Need to buffer aliases during bootup until sysfs becomes > - * available lest we lose that information. > - */ > -struct saved_alias { > - struct kmem_cache *s; > - const char *name; > - struct saved_alias *next; > -}; > - > -static struct saved_alias *alias_list; > - > -static int sysfs_slab_alias(struct kmem_cache *s, const char *name) > -{ > - struct saved_alias *al; > - > - if (slab_state == FULL) { > - /* > - * If we have a leftover link then remove it. > - */ > - sysfs_remove_link(&slab_kset->kobj, name); > - return sysfs_create_link(&slab_kset->kobj, &s->kobj, name); > - } > - > - al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL); > - if (!al) > - return -ENOMEM; > - > - al->s = s; > - al->name = name; > - al->next = alias_list; > - alias_list = al; > - kmsan_unpoison_memory(al, sizeof(*al)); > - return 0; > -} > - > -static int __init slab_sysfs_init(void) > -{ > - struct kmem_cache *s; > - int err; > - > - mutex_lock(&slab_mutex); > - > - slab_kset = kset_create_and_add("slab", NULL, kernel_kobj); > - if (!slab_kset) { > - mutex_unlock(&slab_mutex); > - pr_err("Cannot register slab subsystem.\n"); > - return -ENOSYS; > - } > - > - slab_state = FULL; > - > - list_for_each_entry(s, &slab_caches, list) { > - err = sysfs_slab_add(s); > - if (err) > - pr_err("SLUB: Unable to add boot slab %s to sysfs\n", > - s->name); > - } > - > - while (alias_list) { > - struct saved_alias *al = alias_list; > - > - alias_list = alias_list->next; > - err = sysfs_slab_alias(al->s, al->name); > - if (err) > - pr_err("SLUB: Unable to add boot slab alias %s to sysfs\n", > - al->name); > - kfree(al); > - } > - > - mutex_unlock(&slab_mutex); > - return 0; > -} > -late_initcall(slab_sysfs_init); > -#endif /* SLAB_SUPPORTS_SYSFS */ > - > -#if defined(CONFIG_SLUB_DEBUG) && defined(CONFIG_DEBUG_FS) > -static int slab_debugfs_show(struct seq_file *seq, void *v) > -{ > - struct loc_track *t = seq->private; > - struct location *l; > - unsigned long idx; > - > - idx = (unsigned long) t->idx; > - if (idx < t->count) { > - l = &t->loc[idx]; > - > - seq_printf(seq, "%7ld ", l->count); > - > - if (l->addr) > - seq_printf(seq, "%pS", (void *)l->addr); > - else > - seq_puts(seq, "<not-available>"); > - > - if (l->waste) > - seq_printf(seq, " waste=%lu/%lu", > - l->count * l->waste, l->waste); > - > - if (l->sum_time != l->min_time) { > - seq_printf(seq, " age=%ld/%llu/%ld", > - l->min_time, div_u64(l->sum_time, l->count), > - l->max_time); > - } else > - seq_printf(seq, " age=%ld", l->min_time); > - > - if (l->min_pid != l->max_pid) > - seq_printf(seq, " pid=%ld-%ld", l->min_pid, l->max_pid); > - else > - seq_printf(seq, " pid=%ld", > - l->min_pid); > - > - if (num_online_cpus() > 1 && !cpumask_empty(to_cpumask(l->cpus))) > - seq_printf(seq, " cpus=%*pbl", > - cpumask_pr_args(to_cpumask(l->cpus))); > - > - if (nr_online_nodes > 1 && !nodes_empty(l->nodes)) > - seq_printf(seq, " nodes=%*pbl", > - nodemask_pr_args(&l->nodes)); > - > -#ifdef CONFIG_STACKDEPOT > - { > - depot_stack_handle_t handle; > - unsigned long *entries; > - unsigned int nr_entries, j; > - > - handle = READ_ONCE(l->handle); > - if (handle) { > - nr_entries = stack_depot_fetch(handle, &entries); > - seq_puts(seq, "\n"); > - for (j = 0; j < nr_entries; j++) > - seq_printf(seq, " %pS\n", (void *)entries[j]); > - } > - } > -#endif > - seq_puts(seq, "\n"); > - } > - > - if (!idx && !t->count) > - seq_puts(seq, "No data\n"); > - > - return 0; > -} > - > -static void slab_debugfs_stop(struct seq_file *seq, void *v) > -{ > -} > - > -static void *slab_debugfs_next(struct seq_file *seq, void *v, loff_t *ppos) > -{ > - struct loc_track *t = seq->private; > - > - t->idx = ++(*ppos); > - if (*ppos <= t->count) > - return ppos; > - > - return NULL; > -} > - > -static int cmp_loc_by_count(const void *a, const void *b, const void *data) > -{ > - struct location *loc1 = (struct location *)a; > - struct location *loc2 = (struct location *)b; > - > - if (loc1->count > loc2->count) > - return -1; > - else > - return 1; > -} > - > -static void *slab_debugfs_start(struct seq_file *seq, loff_t *ppos) > -{ > - struct loc_track *t = seq->private; > - > - t->idx = *ppos; > - return ppos; > -} > - > -static const struct seq_operations slab_debugfs_sops = { > - .start = slab_debugfs_start, > - .next = slab_debugfs_next, > - .stop = slab_debugfs_stop, > - .show = slab_debugfs_show, > -}; > - > -static int slab_debug_trace_open(struct inode *inode, struct file *filep) > -{ > - > - struct kmem_cache_node *n; > - enum track_item alloc; > - int node; > - struct loc_track *t = __seq_open_private(filep, &slab_debugfs_sops, > - sizeof(struct loc_track)); > - struct kmem_cache *s = file_inode(filep)->i_private; > - unsigned long *obj_map; > - > - if (!t) > - return -ENOMEM; > - > - obj_map = bitmap_alloc(oo_objects(s->oo), GFP_KERNEL); > - if (!obj_map) { > - seq_release_private(inode, filep); > - return -ENOMEM; > - } > - > - if (strcmp(filep->f_path.dentry->d_name.name, "alloc_traces") == 0) > - alloc = TRACK_ALLOC; > - else > - alloc = TRACK_FREE; > - > - if (!alloc_loc_track(t, PAGE_SIZE / sizeof(struct location), GFP_KERNEL)) { > - bitmap_free(obj_map); > - seq_release_private(inode, filep); > - return -ENOMEM; > - } > - > - for_each_kmem_cache_node(s, node, n) { > - unsigned long flags; > - struct slab *slab; > - > - if (!atomic_long_read(&n->nr_slabs)) > - continue; > - > - spin_lock_irqsave(&n->list_lock, flags); > - list_for_each_entry(slab, &n->partial, slab_list) > - process_slab(t, s, slab, alloc, obj_map); > - list_for_each_entry(slab, &n->full, slab_list) > - process_slab(t, s, slab, alloc, obj_map); > - spin_unlock_irqrestore(&n->list_lock, flags); > - } > - > - /* Sort locations by count */ > - sort_r(t->loc, t->count, sizeof(struct location), > - cmp_loc_by_count, NULL, NULL); > - > - bitmap_free(obj_map); > - return 0; > -} > - > -static int slab_debug_trace_release(struct inode *inode, struct file *file) > -{ > - struct seq_file *seq = file->private_data; > - struct loc_track *t = seq->private; > - > - free_loc_track(t); > - return seq_release_private(inode, file); > -} > - > -static const struct file_operations slab_debugfs_fops = { > - .open = slab_debug_trace_open, > - .read = seq_read, > - .llseek = seq_lseek, > - .release = slab_debug_trace_release, > -}; > - > -static void debugfs_slab_add(struct kmem_cache *s) > -{ > - struct dentry *slab_cache_dir; > - > - if (unlikely(!slab_debugfs_root)) > - return; > - > - slab_cache_dir = debugfs_create_dir(s->name, slab_debugfs_root); > - > - debugfs_create_file("alloc_traces", 0400, > - slab_cache_dir, s, &slab_debugfs_fops); > - > - debugfs_create_file("free_traces", 0400, > - slab_cache_dir, s, &slab_debugfs_fops); > -} > - > -void debugfs_slab_release(struct kmem_cache *s) > -{ > - debugfs_lookup_and_remove(s->name, slab_debugfs_root); > -} > - > -static int __init slab_debugfs_init(void) > -{ > - struct kmem_cache *s; > - > - slab_debugfs_root = debugfs_create_dir("slab", NULL); > - > - list_for_each_entry(s, &slab_caches, list) > - if (s->flags & SLAB_STORE_USER) > - debugfs_slab_add(s); > - > - return 0; > - > -} > -__initcall(slab_debugfs_init); > -#endif > -/* > - * The /proc/slabinfo ABI > - */ > -#ifdef CONFIG_SLUB_DEBUG > -void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo) > -{ > - unsigned long nr_slabs = 0; > - unsigned long nr_objs = 0; > - unsigned long nr_free = 0; > - int node; > - struct kmem_cache_node *n; > - > - for_each_kmem_cache_node(s, node, n) { > - nr_slabs += node_nr_slabs(n); > - nr_objs += node_nr_objs(n); > - nr_free += count_partial(n, count_free); > - } > - > - sinfo->active_objs = nr_objs - nr_free; > - sinfo->num_objs = nr_objs; > - sinfo->active_slabs = nr_slabs; > - sinfo->num_slabs = nr_slabs; > - sinfo->objects_per_slab = oo_objects(s->oo); > - sinfo->cache_order = oo_order(s->oo); > -} > - > -void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s) > -{ > -} > - > -ssize_t slabinfo_write(struct file *file, const char __user *buffer, > - size_t count, loff_t *ppos) > -{ > - return -EIO; > -} > -#endif /* CONFIG_SLUB_DEBUG */
On 4/1/2023 6:46 PM, Vlastimil Babka wrote: > As the SLOB removal is on track and the SLAB removal is planned, I have > realized - why should we stop there and not remove also SLUB? What's a > slab allocator good for in 2023? The RAM sizes are getting larger and > the modules cheaper [1]. The object constructor trick was perhaps > interesting in 1994, but not with contemporary CPUs. So all the slab > allocator does today is just adding an unnecessary layer of complexity > over the page allocator. Oh my goodness, I am on vacation now and looks like someone is pretending to be me. Probably my account was hacked. Please ignore this whole thread. > Thus, with this patch, all three slab allocators are removed, and only a > layer that passes everything to the page allocator remains in the slab.h > and mm/slab_common.c files. This will allow users to gradually > transition away and use the page allocator directly. To summarize the > advantages: > > - Less code to maintain: over 13k lines are removed by this patch, and > more could be removed if I wast^Wspent more time on this, and later as > users are transitioned from the legacy layer. This no longer needs a > separate subsystem so remove it from MAINTAINERS (I hope I can keep the > kernel.org account anyway, though). > > - Simplified MEMCG_KMEM accounting: while I was lazy and just marked it > BROKEN in this patch, it should be trivial to use the page memcg > accounting now that we use the page allocator. The per-object > accounting went through several iterations in the past and was always > complex and added overhead. Page accounting is much simpler by > comparison. > > - Simplified KASAN and friends: also was lazy in this patch so they > can't be enabled but should be easy to fix up and work just on the > page level. > > - Simpler debugging: just use debug_pagealloc=on, no need to look up the > exact syntax of the absurdly complex slub_debug parameter. > > - Speed: didn't measure, but for the page allocator we have pcplists, so > it should scale just fine. No need for the crazy SLUB's cmpxchg_double() > craziness. Maybe that thing could be now removed too? Yeah I can see > just two remaining users. > > Any downsides? Let's look at memory usage after virtme boot: > > Before (with SLUB): > Slab: 26304 kB > > After: > Slab: 295592 kB > > Well, that's not so bad, see [1]. > > [1] https://www.theregister.com/2023/03/29/dram_prices_crash/ > --- > MAINTAINERS | 15 - > include/linux/slab.h | 211 +- > include/linux/slab_def.h | 124 - > include/linux/slub_def.h | 198 -- > init/Kconfig | 2 +- > mm/Kconfig | 134 +- > mm/Makefile | 10 - > mm/slab.c | 4046 ------------------------ > mm/slab.h | 426 --- > mm/slab_common.c | 876 ++--- > mm/slob.c | 757 ----- > mm/slub.c | 6506 -------------------------------------- > 12 files changed, 228 insertions(+), 13077 deletions(-) > delete mode 100644 include/linux/slab_def.h > delete mode 100644 include/linux/slub_def.h > delete mode 100644 mm/slab.c > delete mode 100644 mm/slob.c > delete mode 100644 mm/slub.c > diff --git a/MAINTAINERS b/MAINTAINERS > index 1dc8bd26b6cf..40b05ad03cd0 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -19183,21 +19183,6 @@ F: drivers/irqchip/irq-sl28cpld.c > F: drivers/pwm/pwm-sl28cpld.c > F: drivers/watchdog/sl28cpld_wdt.c > > -SLAB ALLOCATOR > -M: Christoph Lameter <cl@linux.com> > -M: Pekka Enberg <penberg@kernel.org> > -M: David Rientjes <rientjes@google.com> > -M: Joonsoo Kim <iamjoonsoo.kim@lge.com> > -M: Andrew Morton <akpm@linux-foundation.org> > -M: Vlastimil Babka <vbabka@suse.cz> > -R: Roman Gushchin <roman.gushchin@linux.dev> > -R: Hyeonggon Yoo <42.hyeyoo@gmail.com> > -L: linux-mm@kvack.org > -S: Maintained > -T: git git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab.git > -F: include/linux/sl?b*.h > -F: mm/sl?b
On Sat, Apr 01, 2023 at 11:46:58AM +0200, Vlastimil Babka wrote: > As the SLOB removal is on track and the SLAB removal is planned, I have > realized - why should we stop there and not remove also SLUB? What's a > slab allocator good for in 2023? The RAM sizes are getting larger and > the modules cheaper [1]. The object constructor trick was perhaps > interesting in 1994, but not with contemporary CPUs. So all the slab > allocator does today is just adding an unnecessary layer of complexity > over the page allocator. Acked-by: Poisson D'Avril (Oracle) <willy@infradead.org>
From: Vlastimil Babka > Sent: 32 March 2023 10:47 > > As the SLOB removal is on track and the SLAB removal is planned, I have > realized - why should we stop there and not remove also SLUB? What's a > slab allocator good for in 2023? The RAM sizes are getting larger and > the modules cheaper [1]. The object constructor trick was perhaps > interesting in 1994, but not with contemporary CPUs. So all the slab > allocator does today is just adding an unnecessary layer of complexity > over the page allocator. Why stop there? Remove kmalloc() completely. With cheap memory isn't unreasonable to go back to compile-time settable fixed size arrays for all items. Should make 'use after free' much easier to track down. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
Le 01/04/2023 à 20:33, David Laight a écrit : > From: Vlastimil Babka >> Sent: 32 March 2023 10:47 >> >> As the SLOB removal is on track and the SLAB removal is planned, I have >> realized - why should we stop there and not remove also SLUB? What's a >> slab allocator good for in 2023? The RAM sizes are getting larger and >> the modules cheaper [1]. The object constructor trick was perhaps >> interesting in 1994, but not with contemporary CPUs. So all the slab >> allocator does today is just adding an unnecessary layer of complexity >> over the page allocator. > > Why stop there? > Remove kmalloc() completely. > With cheap memory isn't unreasonable to go back to compile-time > settable fixed size arrays for all items. > Should make 'use after free' much easier to track down. > While at it, why not also increase the page size to hugepage size, that would allow us to remove all the complex THP logic, and would remove one level of page tables. I would also reduce TLB pressure. Christophe
From: Christophe Leroy > Sent: 01 April 2023 19:45 > > Le 01/04/2023 à 20:33, David Laight a écrit : > > From: Vlastimil Babka > >> Sent: 32 March 2023 10:47 > >> > >> As the SLOB removal is on track and the SLAB removal is planned, I have > >> realized - why should we stop there and not remove also SLUB? What's a > >> slab allocator good for in 2023? The RAM sizes are getting larger and > >> the modules cheaper [1]. The object constructor trick was perhaps > >> interesting in 1994, but not with contemporary CPUs. So all the slab > >> allocator does today is just adding an unnecessary layer of complexity > >> over the page allocator. > > > > Why stop there? > > Remove kmalloc() completely. > > With cheap memory isn't unreasonable to go back to compile-time > > settable fixed size arrays for all items. > > Should make 'use after free' much easier to track down. > > > > While at it, why not also increase the page size to hugepage size, that > would allow us to remove all the complex THP logic, and would remove one > level of page tables. I would also reduce TLB pressure. Good idea, 4k pages were used on systems where the total system memory was a few MB. Memory system are now easily 1000x times larger - so why not 4MB pages .... David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
On Sat, Apr 1, 2023 at 5:47 PM Vlastimil Babka <vbabka@suse.cz> wrote: > > As the SLOB removal is on track and the SLAB removal is planned, I have > realized - why should we stop there and not remove also SLUB? What's a > slab allocator good for in 2023? The RAM sizes are getting larger and > the modules cheaper [1]. The object constructor trick was perhaps > interesting in 1994, but not with contemporary CPUs. So all the slab > allocator does today is just adding an unnecessary layer of complexity > over the page allocator. > > Thus, with this patch, all three slab allocators are removed, and only a > layer that passes everything to the page allocator remains in the slab.h > and mm/slab_common.c files. This will allow users to gradually > transition away and use the page allocator directly. To summarize the > advantages: > > - Less code to maintain: over 13k lines are removed by this patch, and > more could be removed if I wast^Wspent more time on this, and later as > users are transitioned from the legacy layer. This no longer needs a > separate subsystem so remove it from MAINTAINERS (I hope I can keep the > kernel.org account anyway, though). > > - Simplified MEMCG_KMEM accounting: while I was lazy and just marked it > BROKEN in this patch, it should be trivial to use the page memcg > accounting now that we use the page allocator. The per-object > accounting went through several iterations in the past and was always > complex and added overhead. Page accounting is much simpler by > comparison. > > - Simplified KASAN and friends: also was lazy in this patch so they > can't be enabled but should be easy to fix up and work just on the > page level. > > - Simpler debugging: just use debug_pagealloc=on, no need to look up the > exact syntax of the absurdly complex slub_debug parameter. This really simplifies the complexity of dealing with memory problems in the production environment, and I hope it can be merged into the linux kernel soon. Acked-by: Jeff Xie <xiehuan09@gmail.com>
On 4/1/23 5:46 PM, Vlastimil Babka wrote: > As the SLOB removal is on track and the SLAB removal is planned, I have > realized - why should we stop there and not remove also SLUB? What's a > slab allocator good for in 2023? The RAM sizes are getting larger and > the modules cheaper [1]. The object constructor trick was perhaps > interesting in 1994, but not with contemporary CPUs. So all the slab > allocator does today is just adding an unnecessary layer of complexity > over the page allocator. > > Thus, with this patch, all three slab allocators are removed, and only a > layer that passes everything to the page allocator remains in the slab.h > and mm/slab_common.c files. This will allow users to gradually > transition away and use the page allocator directly. To summarize the > advantages: > > - Less code to maintain: over 13k lines are removed by this patch, and > more could be removed if I wast^Wspent more time on this, and later as > users are transitioned from the legacy layer. This no longer needs a > separate subsystem so remove it from MAINTAINERS (I hope I can keep the > kernel.org account anyway, though). > > - Simplified MEMCG_KMEM accounting: while I was lazy and just marked it > BROKEN in this patch, it should be trivial to use the page memcg > accounting now that we use the page allocator. The per-object > accounting went through several iterations in the past and was always > complex and added overhead. Page accounting is much simpler by > comparison. > > - Simplified KASAN and friends: also was lazy in this patch so they > can't be enabled but should be easy to fix up and work just on the > page level. > > - Simpler debugging: just use debug_pagealloc=on, no need to look up the > exact syntax of the absurdly complex slub_debug parameter. > > - Speed: didn't measure, but for the page allocator we have pcplists, so > it should scale just fine. No need for the crazy SLUB's cmpxchg_double() > craziness. Maybe that thing could be now removed too? Yeah I can see > just two remaining users. > > Any downsides? Let's look at memory usage after virtme boot: > > Before (with SLUB): > Slab: 26304 kB > > After: > Slab: 295592 kB > > Well, that's not so bad, see [1]. > > [1] https://www.theregister.com/2023/03/29/dram_prices_crash/ > --- > MAINTAINERS | 15 - > include/linux/slab.h | 211 +- > include/linux/slab_def.h | 124 - > include/linux/slub_def.h | 198 -- > init/Kconfig | 2 +- > mm/Kconfig | 134 +- > mm/Makefile | 10 - > mm/slab.c | 4046 ------------------------ > mm/slab.h | 426 --- > mm/slab_common.c | 876 ++--- > mm/slob.c | 757 ----- > mm/slub.c | 6506 -------------------------------------- > 12 files changed, 228 insertions(+), 13077 deletions(-) > delete mode 100644 include/linux/slab_def.h > delete mode 100644 include/linux/slub_def.h > delete mode 100644 mm/slab.c > delete mode 100644 mm/slob.c > delete mode 100644 mm/slub.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 1dc8bd26b6cf..40b05ad03cd0 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -19183,21 +19183,6 @@ F: drivers/irqchip/irq-sl28cpld.c > F: drivers/pwm/pwm-sl28cpld.c > F: drivers/watchdog/sl28cpld_wdt.c > > -SLAB ALLOCATOR > -M: Christoph Lameter <cl@linux.com> > -M: Pekka Enberg <penberg@kernel.org> > -M: David Rientjes <rientjes@google.com> > -M: Joonsoo Kim <iamjoonsoo.kim@lge.com> > -M: Andrew Morton <akpm@linux-foundation.org> > -M: Vlastimil Babka <vbabka@suse.cz> > -R: Roman Gushchin <roman.gushchin@linux.dev> > -R: Hyeonggon Yoo <42.hyeyoo@gmail.com> > -L: linux-mm@kvack.org > -S: Maintained > -T: git git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab.git > -F: include/linux/sl?b*.h > -F: mm/sl?b* > - > SLCAN CAN NETWORK DRIVER > M: Dario Binacchi <dario.binacchi@amarulasolutions.com> > L: linux-can@vger.kernel.org > diff --git a/include/linux/slab.h b/include/linux/slab.h > index 45af70315a94..61602d54b1d0 100644 > --- a/include/linux/slab.h > +++ b/include/linux/slab.h > @@ -140,13 +140,14 @@ > > /* The following flags affect the page allocator grouping pages by mobility */ > /* Objects are reclaimable */ > -#ifndef CONFIG_SLUB_TINY > #define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U) > -#else > -#define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0) > -#endif > #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */ > > +#define KMALLOC_NOT_NORMAL_BITS \ > + (__GFP_RECLAIMABLE | \ > + (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ > + (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) > + > /* > * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests. > * > @@ -278,38 +279,11 @@ static inline unsigned int arch_slab_minalign(void) > * Kmalloc array related definitions > */ > > -#ifdef CONFIG_SLAB > -/* > - * SLAB and SLUB directly allocates requests fitting in to an order-1 page > - * (PAGE_SIZE*2). Larger requests are passed to the page allocator. > - */ > -#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) > -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > -#ifndef KMALLOC_SHIFT_LOW > -#define KMALLOC_SHIFT_LOW 5 > -#endif > -#endif > - > -#ifdef CONFIG_SLUB > -#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) > -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > -#ifndef KMALLOC_SHIFT_LOW > -#define KMALLOC_SHIFT_LOW 3 > -#endif > -#endif > - > -#ifdef CONFIG_SLOB > -/* > - * SLOB passes all requests larger than one page to the page allocator. > - * No kmalloc array is necessary since objects of different sizes can > - * be allocated from the same page. > - */ > #define KMALLOC_SHIFT_HIGH PAGE_SHIFT > #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) > #ifndef KMALLOC_SHIFT_LOW > #define KMALLOC_SHIFT_LOW 3 > #endif > -#endif > > /* Maximum allocatable size */ > #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX) > @@ -336,130 +310,6 @@ static inline unsigned int arch_slab_minalign(void) > #define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \ > (KMALLOC_MIN_SIZE) : 16) > > -/* > - * Whenever changing this, take care of that kmalloc_type() and > - * create_kmalloc_caches() still work as intended. > - * > - * KMALLOC_NORMAL can contain only unaccounted objects whereas KMALLOC_CGROUP > - * is for accounted but unreclaimable and non-dma objects. All the other > - * kmem caches can have both accounted and unaccounted objects. > - */ > -enum kmalloc_cache_type { > - KMALLOC_NORMAL = 0, > -#ifndef CONFIG_ZONE_DMA > - KMALLOC_DMA = KMALLOC_NORMAL, > -#endif > -#ifndef CONFIG_MEMCG_KMEM > - KMALLOC_CGROUP = KMALLOC_NORMAL, > -#endif > -#ifdef CONFIG_SLUB_TINY > - KMALLOC_RECLAIM = KMALLOC_NORMAL, > -#else > - KMALLOC_RECLAIM, > -#endif > -#ifdef CONFIG_ZONE_DMA > - KMALLOC_DMA, > -#endif > -#ifdef CONFIG_MEMCG_KMEM > - KMALLOC_CGROUP, > -#endif > - NR_KMALLOC_TYPES > -}; > - > -#ifndef CONFIG_SLOB > -extern struct kmem_cache * > -kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1]; > - > -/* > - * Define gfp bits that should not be set for KMALLOC_NORMAL. > - */ > -#define KMALLOC_NOT_NORMAL_BITS \ > - (__GFP_RECLAIMABLE | \ > - (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ > - (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) > - > -static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) > -{ > - /* > - * The most common case is KMALLOC_NORMAL, so test for it > - * with a single branch for all the relevant flags. > - */ > - if (likely((flags & KMALLOC_NOT_NORMAL_BITS) == 0)) > - return KMALLOC_NORMAL; > - > - /* > - * At least one of the flags has to be set. Their priorities in > - * decreasing order are: > - * 1) __GFP_DMA > - * 2) __GFP_RECLAIMABLE > - * 3) __GFP_ACCOUNT > - */ > - if (IS_ENABLED(CONFIG_ZONE_DMA) && (flags & __GFP_DMA)) > - return KMALLOC_DMA; > - if (!IS_ENABLED(CONFIG_MEMCG_KMEM) || (flags & __GFP_RECLAIMABLE)) > - return KMALLOC_RECLAIM; > - else > - return KMALLOC_CGROUP; > -} > - > -/* > - * Figure out which kmalloc slab an allocation of a certain size > - * belongs to. > - * 0 = zero alloc > - * 1 = 65 .. 96 bytes > - * 2 = 129 .. 192 bytes > - * n = 2^(n-1)+1 .. 2^n > - * > - * Note: __kmalloc_index() is compile-time optimized, and not runtime optimized; > - * typical usage is via kmalloc_index() and therefore evaluated at compile-time. > - * Callers where !size_is_constant should only be test modules, where runtime > - * overheads of __kmalloc_index() can be tolerated. Also see kmalloc_slab(). > - */ > -static __always_inline unsigned int __kmalloc_index(size_t size, > - bool size_is_constant) > -{ > - if (!size) > - return 0; > - > - if (size <= KMALLOC_MIN_SIZE) > - return KMALLOC_SHIFT_LOW; > - > - if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96) > - return 1; > - if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192) > - return 2; > - if (size <= 8) return 3; > - if (size <= 16) return 4; > - if (size <= 32) return 5; > - if (size <= 64) return 6; > - if (size <= 128) return 7; > - if (size <= 256) return 8; > - if (size <= 512) return 9; > - if (size <= 1024) return 10; > - if (size <= 2 * 1024) return 11; > - if (size <= 4 * 1024) return 12; > - if (size <= 8 * 1024) return 13; > - if (size <= 16 * 1024) return 14; > - if (size <= 32 * 1024) return 15; > - if (size <= 64 * 1024) return 16; > - if (size <= 128 * 1024) return 17; > - if (size <= 256 * 1024) return 18; > - if (size <= 512 * 1024) return 19; > - if (size <= 1024 * 1024) return 20; > - if (size <= 2 * 1024 * 1024) return 21; > - > - if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant) > - BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()"); > - else > - BUG(); > - > - /* Will never be reached. Needed because the compiler may complain */ > - return -1; > -} > -static_assert(PAGE_SHIFT <= 20); > -#define kmalloc_index(s) __kmalloc_index(s, true) > -#endif /* !CONFIG_SLOB */ > - > void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __alloc_size(1); > > /** > @@ -567,57 +417,15 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) __assume_page_align > * Try really hard to succeed the allocation but fail > * eventually. > */ > -#ifndef CONFIG_SLOB > -static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) > -{ > - if (__builtin_constant_p(size) && size) { > - unsigned int index; > - > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large(size, flags); > - > - index = kmalloc_index(size); > - return kmalloc_trace( > - kmalloc_caches[kmalloc_type(flags)][index], > - flags, size); > - } > - return __kmalloc(size, flags); > -} > -#else > static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) > { > - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large(size, flags); > - > - return __kmalloc(size, flags); > + return kmalloc_large(size, flags); > } > -#endif > > -#ifndef CONFIG_SLOB > static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) > { > - if (__builtin_constant_p(size) && size) { > - unsigned int index; > - > - if (size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large_node(size, flags, node); > - > - index = kmalloc_index(size); > - return kmalloc_node_trace( > - kmalloc_caches[kmalloc_type(flags)][index], > - flags, node, size); > - } > - return __kmalloc_node(size, flags, node); > + return kmalloc_large_node(size, flags, node); > } > -#else > -static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) > -{ > - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) > - return kmalloc_large_node(size, flags, node); > - > - return __kmalloc_node(size, flags, node); > -} > -#endif > > /** > * kmalloc_array - allocate memory for an array. > @@ -785,12 +593,7 @@ size_t kmalloc_size_roundup(size_t size); > > void __init kmem_cache_init_late(void); > > -#if defined(CONFIG_SMP) && defined(CONFIG_SLAB) > -int slab_prepare_cpu(unsigned int cpu); > -int slab_dead_cpu(unsigned int cpu); > -#else > #define slab_prepare_cpu NULL > #define slab_dead_cpu NULL > -#endif > > #endif /* _LINUX_SLAB_H */ > diff --git a/include/linux/slab_def.h b/include/linux/slab_def.h > deleted file mode 100644 > index a61e7d55d0d3..000000000000 > --- a/include/linux/slab_def.h > +++ /dev/null > @@ -1,124 +0,0 @@ > -/* SPDX-License-Identifier: GPL-2.0 */ > -#ifndef _LINUX_SLAB_DEF_H > -#define _LINUX_SLAB_DEF_H > - > -#include <linux/kfence.h> > -#include <linux/reciprocal_div.h> > - > -/* > - * Definitions unique to the original Linux SLAB allocator. > - */ > - > -struct kmem_cache { > - struct array_cache __percpu *cpu_cache; > - > -/* 1) Cache tunables. Protected by slab_mutex */ > - unsigned int batchcount; > - unsigned int limit; > - unsigned int shared; > - > - unsigned int size; > - struct reciprocal_value reciprocal_buffer_size; > -/* 2) touched by every alloc & free from the backend */ > - > - slab_flags_t flags; /* constant flags */ > - unsigned int num; /* # of objs per slab */ > - > -/* 3) cache_grow/shrink */ > - /* order of pgs per slab (2^n) */ > - unsigned int gfporder; > - > - /* force GFP flags, e.g. GFP_DMA */ > - gfp_t allocflags; > - > - size_t colour; /* cache colouring range */ > - unsigned int colour_off; /* colour offset */ > - unsigned int freelist_size; > - > - /* constructor func */ > - void (*ctor)(void *obj); > - > -/* 4) cache creation/removal */ > - const char *name; > - struct list_head list; > - int refcount; > - int object_size; > - int align; > - > -/* 5) statistics */ > -#ifdef CONFIG_DEBUG_SLAB > - unsigned long num_active; > - unsigned long num_allocations; > - unsigned long high_mark; > - unsigned long grown; > - unsigned long reaped; > - unsigned long errors; > - unsigned long max_freeable; > - unsigned long node_allocs; > - unsigned long node_frees; > - unsigned long node_overflow; > - atomic_t allochit; > - atomic_t allocmiss; > - atomic_t freehit; > - atomic_t freemiss; > - > - /* > - * If debugging is enabled, then the allocator can add additional > - * fields and/or padding to every object. 'size' contains the total > - * object size including these internal fields, while 'obj_offset' > - * and 'object_size' contain the offset to the user object and its > - * size. > - */ > - int obj_offset; > -#endif /* CONFIG_DEBUG_SLAB */ > - > -#ifdef CONFIG_KASAN_GENERIC > - struct kasan_cache kasan_info; > -#endif > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > - unsigned int *random_seq; > -#endif > - > -#ifdef CONFIG_HARDENED_USERCOPY > - unsigned int useroffset; /* Usercopy region offset */ > - unsigned int usersize; /* Usercopy region size */ > -#endif > - > - struct kmem_cache_node *node[MAX_NUMNODES]; > -}; > - > -static inline void *nearest_obj(struct kmem_cache *cache, const struct slab *slab, > - void *x) > -{ > - void *object = x - (x - slab->s_mem) % cache->size; > - void *last_object = slab->s_mem + (cache->num - 1) * cache->size; > - > - if (unlikely(object > last_object)) > - return last_object; > - else > - return object; > -} > - > -/* > - * We want to avoid an expensive divide : (offset / cache->size) > - * Using the fact that size is a constant for a particular cache, > - * we can replace (offset / cache->size) by > - * reciprocal_divide(offset, cache->reciprocal_buffer_size) > - */ > -static inline unsigned int obj_to_index(const struct kmem_cache *cache, > - const struct slab *slab, void *obj) > -{ > - u32 offset = (obj - slab->s_mem); > - return reciprocal_divide(offset, cache->reciprocal_buffer_size); > -} > - > -static inline int objs_per_slab(const struct kmem_cache *cache, > - const struct slab *slab) > -{ > - if (is_kfence_address(slab_address(slab))) > - return 1; > - return cache->num; > -} > - > -#endif /* _LINUX_SLAB_DEF_H */ > diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h > deleted file mode 100644 > index f6df03f934e5..000000000000 > --- a/include/linux/slub_def.h > +++ /dev/null > @@ -1,198 +0,0 @@ > -/* SPDX-License-Identifier: GPL-2.0 */ > -#ifndef _LINUX_SLUB_DEF_H > -#define _LINUX_SLUB_DEF_H > - > -/* > - * SLUB : A Slab allocator without object queues. > - * > - * (C) 2007 SGI, Christoph Lameter > - */ > -#include <linux/kfence.h> > -#include <linux/kobject.h> > -#include <linux/reciprocal_div.h> > -#include <linux/local_lock.h> > - > -enum stat_item { > - ALLOC_FASTPATH, /* Allocation from cpu slab */ > - ALLOC_SLOWPATH, /* Allocation by getting a new cpu slab */ > - FREE_FASTPATH, /* Free to cpu slab */ > - FREE_SLOWPATH, /* Freeing not to cpu slab */ > - FREE_FROZEN, /* Freeing to frozen slab */ > - FREE_ADD_PARTIAL, /* Freeing moves slab to partial list */ > - FREE_REMOVE_PARTIAL, /* Freeing removes last object */ > - ALLOC_FROM_PARTIAL, /* Cpu slab acquired from node partial list */ > - ALLOC_SLAB, /* Cpu slab acquired from page allocator */ > - ALLOC_REFILL, /* Refill cpu slab from slab freelist */ > - ALLOC_NODE_MISMATCH, /* Switching cpu slab */ > - FREE_SLAB, /* Slab freed to the page allocator */ > - CPUSLAB_FLUSH, /* Abandoning of the cpu slab */ > - DEACTIVATE_FULL, /* Cpu slab was full when deactivated */ > - DEACTIVATE_EMPTY, /* Cpu slab was empty when deactivated */ > - DEACTIVATE_TO_HEAD, /* Cpu slab was moved to the head of partials */ > - DEACTIVATE_TO_TAIL, /* Cpu slab was moved to the tail of partials */ > - DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */ > - DEACTIVATE_BYPASS, /* Implicit deactivation */ > - ORDER_FALLBACK, /* Number of times fallback was necessary */ > - CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */ > - CMPXCHG_DOUBLE_FAIL, /* Number of times that cmpxchg double did not match */ > - CPU_PARTIAL_ALLOC, /* Used cpu partial on alloc */ > - CPU_PARTIAL_FREE, /* Refill cpu partial on free */ > - CPU_PARTIAL_NODE, /* Refill cpu partial from node partial */ > - CPU_PARTIAL_DRAIN, /* Drain cpu partial to node partial */ > - NR_SLUB_STAT_ITEMS }; > - > -#ifndef CONFIG_SLUB_TINY > -/* > - * When changing the layout, make sure freelist and tid are still compatible > - * with this_cpu_cmpxchg_double() alignment requirements. > - */ > -struct kmem_cache_cpu { > - void **freelist; /* Pointer to next available object */ > - unsigned long tid; /* Globally unique transaction id */ > - struct slab *slab; /* The slab from which we are allocating */ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - struct slab *partial; /* Partially allocated frozen slabs */ > -#endif > - local_lock_t lock; /* Protects the fields above */ > -#ifdef CONFIG_SLUB_STATS > - unsigned stat[NR_SLUB_STAT_ITEMS]; > -#endif > -}; > -#endif /* CONFIG_SLUB_TINY */ > - > -#ifdef CONFIG_SLUB_CPU_PARTIAL > -#define slub_percpu_partial(c) ((c)->partial) > - > -#define slub_set_percpu_partial(c, p) \ > -({ \ > - slub_percpu_partial(c) = (p)->next; \ > -}) > - > -#define slub_percpu_partial_read_once(c) READ_ONCE(slub_percpu_partial(c)) > -#else > -#define slub_percpu_partial(c) NULL > - > -#define slub_set_percpu_partial(c, p) > - > -#define slub_percpu_partial_read_once(c) NULL > -#endif // CONFIG_SLUB_CPU_PARTIAL > - > -/* > - * Word size structure that can be atomically updated or read and that > - * contains both the order and the number of objects that a slab of the > - * given order would contain. > - */ > -struct kmem_cache_order_objects { > - unsigned int x; > -}; > - > -/* > - * Slab cache management. > - */ > -struct kmem_cache { > -#ifndef CONFIG_SLUB_TINY > - struct kmem_cache_cpu __percpu *cpu_slab; > -#endif > - /* Used for retrieving partial slabs, etc. */ > - slab_flags_t flags; > - unsigned long min_partial; > - unsigned int size; /* The size of an object including metadata */ > - unsigned int object_size;/* The size of an object without metadata */ > - struct reciprocal_value reciprocal_size; > - unsigned int offset; /* Free pointer offset */ > -#ifdef CONFIG_SLUB_CPU_PARTIAL > - /* Number of per cpu partial objects to keep around */ > - unsigned int cpu_partial; > - /* Number of per cpu partial slabs to keep around */ > - unsigned int cpu_partial_slabs; > -#endif > - struct kmem_cache_order_objects oo; > - > - /* Allocation and freeing of slabs */ > - struct kmem_cache_order_objects min; > - gfp_t allocflags; /* gfp flags to use on each alloc */ > - int refcount; /* Refcount for slab cache destroy */ > - void (*ctor)(void *); > - unsigned int inuse; /* Offset to metadata */ > - unsigned int align; /* Alignment */ > - unsigned int red_left_pad; /* Left redzone padding size */ > - const char *name; /* Name (only for display!) */ > - struct list_head list; /* List of slab caches */ > -#ifdef CONFIG_SYSFS > - struct kobject kobj; /* For sysfs */ > -#endif > -#ifdef CONFIG_SLAB_FREELIST_HARDENED > - unsigned long random; > -#endif > - > -#ifdef CONFIG_NUMA > - /* > - * Defragmentation by allocating from a remote node. > - */ > - unsigned int remote_node_defrag_ratio; > -#endif > - > -#ifdef CONFIG_SLAB_FREELIST_RANDOM > - unsigned int *random_seq; > -#endif > - > -#ifdef CONFIG_KASAN_GENERIC > - struct kasan_cache kasan_info; > -#endif > - > -#ifdef CONFIG_HARDENED_USERCOPY > - unsigned int useroffset; /* Usercopy region offset */ > - unsigned int usersize; /* Usercopy region size */ > -#endif > - > - struct kmem_cache_node *node[MAX_NUMNODES]; > -}; > - > -#if defined(CONFIG_SYSFS) && !defined(CONFIG_SLUB_TINY) > -#define SLAB_SUPPORTS_SYSFS > -void sysfs_slab_unlink(struct kmem_cache *); > -void sysfs_slab_release(struct kmem_cache *); > -#else > -static inline void sysfs_slab_unlink(struct kmem_cache *s) > -{ > -} > -static inline void sysfs_slab_release(struct kmem_cache *s) > -{ > -} > -#endif > - > -void *fixup_red_left(struct kmem_cache *s, void *p); > - > -static inline void *nearest_obj(struct kmem_cache *cache, const struct slab *slab, > - void *x) { > - void *object = x - (x - slab_address(slab)) % cache->size; > - void *last_object = slab_address(slab) + > - (slab->objects - 1) * cache->size; > - void *result = (unlikely(object > last_object)) ? last_object : object; > - > - result = fixup_red_left(cache, result); > - return result; > -} > - > -/* Determine object index from a given position */ > -static inline unsigned int __obj_to_index(const struct kmem_cache *cache, > - void *addr, void *obj) > -{ > - return reciprocal_divide(kasan_reset_tag(obj) - addr, > - cache->reciprocal_size); > -} > - > -static inline unsigned int obj_to_index(const struct kmem_cache *cache, > - const struct slab *slab, void *obj) > -{ > - if (is_kfence_address(obj)) > - return 0; > - return __obj_to_index(cache, slab_address(slab), obj); > -} > - > -static inline int objs_per_slab(const struct kmem_cache *cache, > - const struct slab *slab) > -{ > - return slab->objects; > -} > -#endif /* _LINUX_SLUB_DEF_H */ > diff --git a/init/Kconfig b/init/Kconfig > index 1fb5f313d18f..45be2eedf75c 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -973,7 +973,7 @@ config MEMCG > > config MEMCG_KMEM > bool > - depends on MEMCG && !SLOB > + depends on MEMCG && BROKEN > default y > > config BLK_CGROUP > diff --git a/mm/Kconfig b/mm/Kconfig > index 4751031f3f05..f07e81bca39e 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -210,134 +210,9 @@ config ZSMALLOC_CHAIN_SIZE > > For more information, see zsmalloc documentation. > > -menu "SLAB allocator options" > - > -choice > - prompt "Choose SLAB allocator" > - default SLUB > - help > - This option allows to select a slab allocator. > - > -config SLAB > - bool "SLAB" > - depends on !PREEMPT_RT > - select HAVE_HARDENED_USERCOPY_ALLOCATOR > - help > - The regular slab allocator that is established and known to work > - well in all environments. It organizes cache hot objects in > - per cpu and per node queues. > - > -config SLUB > - bool "SLUB (Unqueued Allocator)" > - select HAVE_HARDENED_USERCOPY_ALLOCATOR > - help > - SLUB is a slab allocator that minimizes cache line usage > - instead of managing queues of cached objects (SLAB approach). > - Per cpu caching is realized using slabs of objects instead > - of queues of objects. SLUB can use memory efficiently > - and has enhanced diagnostics. SLUB is the default choice for > - a slab allocator. > - > -config SLOB_DEPRECATED > - depends on EXPERT > - bool "SLOB (Simple Allocator - DEPRECATED)" > - depends on !PREEMPT_RT > - help > - Deprecated and scheduled for removal in a few cycles. SLUB > - recommended as replacement. CONFIG_SLUB_TINY can be considered > - on systems with 16MB or less RAM. > - > - If you need SLOB to stay, please contact linux-mm@kvack.org and > - people listed in the SLAB ALLOCATOR section of MAINTAINERS file, > - with your use case. > - > - SLOB replaces the stock allocator with a drastically simpler > - allocator. SLOB is generally more space efficient but > - does not perform as well on large systems. > - > -endchoice > - > -config SLOB > - bool > - default y > - depends on SLOB_DEPRECATED > - > -config SLUB_TINY > - bool "Configure SLUB for minimal memory footprint" > - depends on SLUB && EXPERT > - select SLAB_MERGE_DEFAULT > - help > - Configures the SLUB allocator in a way to achieve minimal memory > - footprint, sacrificing scalability, debugging and other features. > - This is intended only for the smallest system that had used the > - SLOB allocator and is not recommended for systems with more than > - 16MB RAM. > - > - If unsure, say N. > - > -config SLAB_MERGE_DEFAULT > - bool "Allow slab caches to be merged" > - default y > - depends on SLAB || SLUB > - help > - For reduced kernel memory fragmentation, slab caches can be > - merged when they share the same size and other characteristics. > - This carries a risk of kernel heap overflows being able to > - overwrite objects from merged caches (and more easily control > - cache layout), which makes such heap attacks easier to exploit > - by attackers. By keeping caches unmerged, these kinds of exploits > - can usually only damage objects in the same cache. To disable > - merging at runtime, "slab_nomerge" can be passed on the kernel > - command line. > - > -config SLAB_FREELIST_RANDOM > - bool "Randomize slab freelist" > - depends on SLAB || (SLUB && !SLUB_TINY) > - help > - Randomizes the freelist order used on creating new pages. This > - security feature reduces the predictability of the kernel slab > - allocator against heap overflows. > - > -config SLAB_FREELIST_HARDENED > - bool "Harden slab freelist metadata" > - depends on SLAB || (SLUB && !SLUB_TINY) > - help > - Many kernel heap attacks try to target slab cache metadata and > - other infrastructure. This options makes minor performance > - sacrifices to harden the kernel slab allocator against common > - freelist exploit methods. Some slab implementations have more > - sanity-checking than others. This option is most effective with > - CONFIG_SLUB. > - > -config SLUB_STATS > - default n > - bool "Enable SLUB performance statistics" > - depends on SLUB && SYSFS && !SLUB_TINY > - help > - SLUB statistics are useful to debug SLUBs allocation behavior in > - order find ways to optimize the allocator. This should never be > - enabled for production use since keeping statistics slows down > - the allocator by a few percentage points. The slabinfo command > - supports the determination of the most active slabs to figure > - out which slabs are relevant to a particular load. > - Try running: slabinfo -DA > - > -config SLUB_CPU_PARTIAL > - default y > - depends on SLUB && SMP && !SLUB_TINY > - bool "SLUB per cpu partial cache" > - help > - Per cpu partial caches accelerate objects allocation and freeing > - that is local to a processor at the price of more indeterminism > - in the latency of the free. On overflow these caches will be cleared > - which requires the taking of locks that may cause latency spikes. > - Typically one would choose no for a realtime system. > - > -endmenu # SLAB allocator options > - > config SHUFFLE_PAGE_ALLOCATOR > bool "Page allocator randomization" > - default SLAB_FREELIST_RANDOM && ACPI_NUMA > + default ACPI_NUMA > help > Randomization of the page allocator improves the average > utilization of a direct-mapped memory-side-cache. See section > @@ -345,10 +220,9 @@ config SHUFFLE_PAGE_ALLOCATOR > 6.2a specification for an example of how a platform advertises > the presence of a memory-side-cache. There are also incidental > security benefits as it reduces the predictability of page > - allocations to compliment SLAB_FREELIST_RANDOM, but the > - default granularity of shuffling on the "MAX_ORDER - 1" i.e, > - 10th order of pages is selected based on cache utilization > - benefits on x86. > + allocations, but the default granularity of shuffling on the > + "MAX_ORDER - 1" i.e, 10th order of pages is selected based on > + cache utilization benefits on x86. > > While the randomization improves cache utilization it may > negatively impact workloads on platforms without a cache. For > diff --git a/mm/Makefile b/mm/Makefile > index 8e105e5b3e29..18b0bb245fc3 100644 > --- a/mm/Makefile > +++ b/mm/Makefile > @@ -4,16 +4,12 @@ > # > > KASAN_SANITIZE_slab_common.o := n > -KASAN_SANITIZE_slab.o := n > -KASAN_SANITIZE_slub.o := n > KCSAN_SANITIZE_kmemleak.o := n > > # These produce frequent data race reports: most of them are due to races on > # the same word but accesses to different bits of that word. Re-enable KCSAN > # for these when we have more consensus on what to do about them. > KCSAN_SANITIZE_slab_common.o := n > -KCSAN_SANITIZE_slab.o := n > -KCSAN_SANITIZE_slub.o := n > KCSAN_SANITIZE_page_alloc.o := n > # But enable explicit instrumentation for memory barriers. > KCSAN_INSTRUMENT_BARRIERS := y > @@ -22,9 +18,6 @@ KCSAN_INSTRUMENT_BARRIERS := y > # flaky coverage that is not a function of syscall inputs. E.g. slab is out of > # free pages, or a task is migrated between nodes. > KCOV_INSTRUMENT_slab_common.o := n > -KCOV_INSTRUMENT_slob.o := n > -KCOV_INSTRUMENT_slab.o := n > -KCOV_INSTRUMENT_slub.o := n > KCOV_INSTRUMENT_page_alloc.o := n > KCOV_INSTRUMENT_debug-pagealloc.o := n > KCOV_INSTRUMENT_kmemleak.o := n > @@ -81,12 +74,9 @@ obj-$(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP) += hugetlb_vmemmap.o > obj-$(CONFIG_NUMA) += mempolicy.o > obj-$(CONFIG_SPARSEMEM) += sparse.o > obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o > -obj-$(CONFIG_SLOB) += slob.o > obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o > obj-$(CONFIG_KSM) += ksm.o > obj-$(CONFIG_PAGE_POISONING) += page_poison.o > -obj-$(CONFIG_SLAB) += slab.o > -obj-$(CONFIG_SLUB) += slub.o > obj-$(CONFIG_KASAN) += kasan/ > obj-$(CONFIG_KFENCE) += kfence/ > obj-$(CONFIG_KMSAN) += kmsan/ > diff --git a/mm/slab.c b/mm/slab.c > deleted file mode 100644 > index edbe722fb906..000000000000 > --- a/mm/slab.c > +++ /dev/null > @@ -1,4046 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * linux/mm/slab.c > - * Written by Mark Hemment, 1996/97. > - * (markhe@nextd.demon.co.uk) > - * > - * kmem_cache_destroy() + some cleanup - 1999 Andrea Arcangeli > - * > - * Major cleanup, different bufctl logic, per-cpu arrays > - * (c) 2000 Manfred Spraul > - * > - * Cleanup, make the head arrays unconditional, preparation for NUMA > - * (c) 2002 Manfred Spraul > - * > - * An implementation of the Slab Allocator as described in outline in; > - * UNIX Internals: The New Frontiers by Uresh Vahalia > - * Pub: Prentice Hall ISBN 0-13-101908-2 > - * or with a little more detail in; > - * The Slab Allocator: An Object-Caching Kernel Memory Allocator > - * Jeff Bonwick (Sun Microsystems). > - * Presented at: USENIX Summer 1994 Technical Conference > - * > - * The memory is organized in caches, one cache for each object type. > - * (e.g. inode_cache, dentry_cache, buffer_head, vm_area_struct) > - * Each cache consists out of many slabs (they are small (usually one > - * page long) and always contiguous), and each slab contains multiple > - * initialized objects. > - * > - * This means, that your constructor is used only for newly allocated > - * slabs and you must pass objects with the same initializations to > - * kmem_cache_free. > - * > - * Each cache can only support one memory type (GFP_DMA, GFP_HIGHMEM, > - * normal). If you need a special memory type, then must create a new > - * cache for that memory type. > - * > - * In order to reduce fragmentation, the slabs are sorted in 3 groups: > - * full slabs with 0 free objects > - * partial slabs > - * empty slabs with no allocated objects > - * > - * If partial slabs exist, then new allocations come from these slabs, > - * otherwise from empty slabs or new slabs are allocated. > - * > - * kmem_cache_destroy() CAN CRASH if you try to allocate from the cache > - * during kmem_cache_destroy(). The caller must prevent concurrent allocs. > - * > - * Each cache has a short per-cpu head array, most allocs > - * and frees go into that array, and if that array overflows, then 1/2 > - * of the entries in the array are given back into the global cache. > - * The head array is strictly LIFO and should improve the cache hit rates. > - * On SMP, it additionally reduces the spinlock operations. > - * > - * The c_cpuarray may not be read with enabled local interrupts - > - * it's changed with a smp_call_function(). > - * > - * SMP synchronization: > - * constructors and destructors are called without any locking. > - * Several members in struct kmem_cache and struct slab never change, they > - * are accessed without any locking. > - * The per-cpu arrays are never accessed from the wrong cpu, no locking, > - * and local interrupts are disabled so slab code is preempt-safe. > - * The non-constant members are protected with a per-cache irq spinlock. > - * > - * Many thanks to Mark Hemment, who wrote another per-cpu slab patch > - * in 2000 - many ideas in the current implementation are derived from > - * his patch. > - * > - * Further notes from the original documentation: > - * > - * 11 April '97. Started multi-threading - markhe > - * The global cache-chain is protected by the mutex 'slab_mutex'. > - * The sem is only needed when accessing/extending the cache-chain, which > - * can never happen inside an interrupt (kmem_cache_create(), > - * kmem_cache_shrink() and kmem_cache_reap()). > - * > - * At present, each engine can be growing a cache. This should be blocked. > - * > - * 15 March 2005. NUMA slab allocator. > - * Shai Fultheim <shai@scalex86.org>. > - * Shobhit Dayal <shobhit@calsoftinc.com> > - * Alok N Kataria <alokk@calsoftinc.com> > - * Christoph Lameter <christoph@lameter.com> > - * > - * Modified the slab allocator to be node aware on NUMA systems. > - * Each node has its own list of partial, free and full slabs. > - * All object allocations for a node occur from node specific slab lists. > - */ > - > -#include <linux/slab.h> > -#include <linux/mm.h> > -#include <linux/poison.h> > -#include <linux/swap.h> > -#include <linux/cache.h> > -#include <linux/interrupt.h> > -#include <linux/init.h> > -#include <linux/compiler.h> > -#include <linux/cpuset.h> > -#include <linux/proc_fs.h> > -#include <linux/seq_file.h> > -#include <linux/notifier.h> > -#include <linux/kallsyms.h> > -#include <linux/kfence.h> > -#include <linux/cpu.h> > -#include <linux/sysctl.h> > -#include <linux/module.h> > -#include <linux/rcupdate.h> > -#include <linux/string.h> > -#include <linux/uaccess.h> > -#include <linux/nodemask.h> > -#include <linux/kmemleak.h> > -#include <linux/mempolicy.h> > -#include <linux/mutex.h> > -#include <linux/fault-inject.h> > -#include <linux/rtmutex.h> > -#include <linux/reciprocal_div.h> > -#include <linux/debugobjects.h> > -#include <linux/memory.h> > -#include <linux/prefetch.h> > -#include <linux/sched/task_stack.h> > - > -#include <net/sock.h> > - > -#include <asm/cacheflush.h> > -#include <asm/tlbflush.h> > -#include <asm/page.h> > - > -#include <trace/events/kmem.h> > - > -#include "internal.h" > - > -#include "slab.h" > - > -/* > - * DEBUG - 1 for kmem_cache_create() to honour; SLAB_RED_ZONE & SLAB_POISON. > - * 0 for faster, smaller code (especially in the critical paths). > - * > - * STATS - 1 to collect stats for /proc/slabinfo. > - * 0 for faster, smaller code (especially in the critical paths). > - * > - * FORCED_DEBUG - 1 enables SLAB_RED_ZONE and SLAB_POISON (if possible) > - */ > - > -#ifdef CONFIG_DEBUG_SLAB > -#define DEBUG 1 > -#define STATS 1 > -#define FORCED_DEBUG 1 > -#else > -#define DEBUG 0 > -#define STATS 0 > -#define FORCED_DEBUG 0 > -#endif > - > -/* Shouldn't this be in a header file somewhere? */ > -#define BYTES_PER_WORD sizeof(void *) > -#define REDZONE_ALIGN max(BYTES_PER_WORD, __alignof__(unsigned long long)) > - > -#ifndef ARCH_KMALLOC_FLAGS > -#define ARCH_KMALLOC_FLAGS SLAB_HWCACHE_ALIGN > -#endif > - > -#define FREELIST_BYTE_INDEX (((PAGE_SIZE >> BITS_PER_BYTE) \ > - <= SLAB_OBJ_MIN_SIZE) ? 1 : 0) > - > -#if FREELIST_BYTE_INDEX > -typedef unsigned char freelist_idx_t; > -#else > -typedef unsigned short freelist_idx_t; > -#endif > - > -#define SLAB_OBJ_MAX_NUM ((1 << sizeof(freelist_idx_t) * BITS_PER_BYTE) - 1) > - > -/* > - * struct array_cache > - * > - * Purpose: > - * - LIFO ordering, to hand out cache-warm objects from _alloc > - * - reduce the number of linked list operations > - * - reduce spinlock operations > - * > - * The limit is stored in the per-cpu structure to reduce the data cache > - * footprint. > - * > - */ > -struct array_cache { > - unsigned int avail; > - unsigned int limit; > - unsigned int batchcount; > - unsigned int touched; > - void *entry[]; /* > - * Must have this definition in here for the proper > - * alignment of array_cache. Also simplifies accessing > - * the entries. > - */ > -}; > - > -struct alien_cache { > - spinlock_t lock; > - struct array_cache ac; > -}; > - > -/* > - * Need this for bootstrapping a per node allocator. > - */ > -#define NUM_INIT_LISTS (2 * MAX_NUMNODES) > -static struct kmem_cache_node __initdata init_kmem_cache_node[NUM_INIT_LISTS]; > -#define CACHE_CACHE 0 > -#define SIZE_NODE (MAX_NUMNODES) > - > -static int drain_freelist(struct kmem_cache *cache, > - struct kmem_cache_node *n, int tofree); > -static void free_block(struct kmem_cache *cachep, void **objpp, int len, > - int node, struct list_head *list); > -static void slabs_destroy(struct kmem_cache *cachep, struct list_head *list); > -static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp); > -static void cache_reap(struct work_struct *unused); > - > -static inline void fixup_objfreelist_debug(struct kmem_cache *cachep, > - void **list); > -static inline void fixup_slab_list(struct kmem_cache *cachep, > - struct kmem_cache_node *n, struct slab *slab, > - void **list); > - > -#define INDEX_NODE kmalloc_index(sizeof(struct kmem_cache_node)) > - > -static void kmem_cache_node_init(struct kmem_cache_node *parent) > -{ > - INIT_LIST_HEAD(&parent->slabs_full); > - INIT_LIST_HEAD(&parent->slabs_partial); > - INIT_LIST_HEAD(&parent->slabs_free); > - parent->total_slabs = 0; > - parent->free_slabs = 0; > - parent->shared = NULL; > - parent->alien = NULL; > - parent->colour_next = 0; > - raw_spin_lock_init(&parent->list_lock); > - parent->free_objects = 0; > - parent->free_touched = 0; > -} > - > -#define MAKE_LIST(cachep, listp, slab, nodeid) \ > - do { \ > - INIT_LIST_HEAD(listp); \ > - list_splice(&get_node(cachep, nodeid)->slab, listp); \ > - } while (0) > - > -#define MAKE_ALL_LISTS(cachep, ptr, nodeid) \ > - do { \ > - MAKE_LIST((cachep), (&(ptr)->slabs_full), slabs_full, nodeid); \ > - MAKE_LIST((cachep), (&(ptr)->slabs_partial), slabs_partial, nodeid); \ > - MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid); \ > - } while (0) > - > -#define CFLGS_OBJFREELIST_SLAB ((slab_flags_t __force)0x40000000U) > -#define CFLGS_OFF_SLAB ((slab_flags_t __force)0x80000000U) > -#define OBJFREELIST_SLAB(x) ((x)->flags & CFLGS_OBJFREELIST_SLAB) > -#define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB) > - > -#define BATCHREFILL_LIMIT 16 > -/* > - * Optimization question: fewer reaps means less probability for unnecessary > - * cpucache drain/refill cycles. > - * > - * OTOH the cpuarrays can contain lots of objects, > - * which could lock up otherwise freeable slabs. > - */ > -#define REAPTIMEOUT_AC (2*HZ) > -#define REAPTIMEOUT_NODE (4*HZ) > - > -#if STATS > -#define STATS_INC_ACTIVE(x) ((x)->num_active++) > -#define STATS_DEC_ACTIVE(x) ((x)->num_active--) > -#define STATS_INC_ALLOCED(x) ((x)->num_allocations++) > -#define STATS_INC_GROWN(x) ((x)->grown++) > -#define STATS_ADD_REAPED(x, y) ((x)->reaped += (y)) > -#define STATS_SET_HIGH(x) \ > - do { \ > - if ((x)->num_active > (x)->high_mark) \ > - (x)->high_mark = (x)->num_active; \ > - } while (0) > -#define STATS_INC_ERR(x) ((x)->errors++) > -#define STATS_INC_NODEALLOCS(x) ((x)->node_allocs++) > -#define STATS_INC_NODEFREES(x) ((x)->node_frees++) > -#define STATS_INC_ACOVERFLOW(x) ((x)->node_overflow++) > -#define STATS_SET_FREEABLE(x, i) \ > - do { \ > - if ((x)->max_freeable < i) \ > - (x)->max_freeable = i; \ > - } while (0) > -#define STATS_INC_ALLOCHIT(x) atomic_inc(&(x)->allochit) > -#define STATS_INC_ALLOCMISS(x) atomic_inc(&(x)->allocmiss) > -#define STATS_INC_FREEHIT(x) atomic_inc(&(x)->freehit) > -#define STATS_INC_FREEMISS(x) atomic_inc(&(x)->freemiss) > -#else > -#define STATS_INC_ACTIVE(x) do { } while (0) > -#define STATS_DEC_ACTIVE(x) do { } while (0) > -#define STATS_INC_ALLOCED(x) do { } while (0) > -#define STATS_INC_GROWN(x) do { } while (0) > -#define STATS_ADD_REAPED(x, y) do { (void)(y); } while (0) > -#define STATS_SET_HIGH(x) do { } while (0) > -#define STATS_INC_ERR(x) do { } while (0) > -#define STATS_INC_NODEALLOCS(x) do { } while (0) > -#define STATS_INC_NODEFREES(x) do { } while (0) > -#define STATS_INC_ACOVERFLOW(x) do { } while (0) > -#define STATS_SET_FREEABLE(x, i) do { } while (0) > -#define STATS_INC_ALLOCHIT(x) do { } while (0) > -#define STATS_INC_ALLOCMISS(x) do { } while (0) > -#define STATS_INC_FREEHIT(x) do { } while (0) > -#define STATS_INC_FREEMISS(x) do { } while (0) > -#endif > - > -#if DEBUG > - > -/* > - * memory layout of objects: > - * 0 : objp > - * 0 .. cachep->obj_offset - BYTES_PER_WORD - 1: padding. This ensures that > - * the end of an object is aligned with the end of the real > - * allocation. Catches writes behind the end of the allocation. > - * cachep->obj_offset - BYTES_PER_WORD .. cachep->obj_offset - 1: > - * redzone word. > - * cachep->obj_offset: The real object. > - * cachep->size - 2* BYTES_PER_WORD: redzone word [BYTES_PER_WORD long] > - * cachep->size - 1* BYTES_PER_WORD: last caller address > - * [BYTES_PER_WORD long] > - */ > -static int obj_offset(struct kmem_cache *cachep) > -{ > - return cachep->obj_offset; > -} > - > -static unsigned long long *dbg_redzone1(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); > - return (unsigned long long *) (objp + obj_offset(cachep) - > - sizeof(unsigned long long)); > -} > - > -static unsigned long long *dbg_redzone2(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); > - if (cachep->flags & SLAB_STORE_USER) > - return (unsigned long long *)(objp + cachep->size - > - sizeof(unsigned long long) - > - REDZONE_ALIGN); > - return (unsigned long long *) (objp + cachep->size - > - sizeof(unsigned long long)); > -} > - > -static void **dbg_userword(struct kmem_cache *cachep, void *objp) > -{ > - BUG_ON(!(cachep->flags & SLAB_STORE_USER)); > - return (void **)(objp + cachep->size - BYTES_PER_WORD); > -} > - > -#else > - > -#define obj_offset(x) 0 > -#define dbg_redzone1(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) > -#define dbg_redzone2(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) > -#define dbg_userword(cachep, objp) ({BUG(); (void **)NULL;}) > - > -#endif > - > -/* > - * Do not go above this order unless 0 objects fit into the slab or > - * overridden on the command line. > - */ > -#define SLAB_MAX_ORDER_HI 1 > -#define SLAB_MAX_ORDER_LO 0 > -static int slab_max_order = SLAB_MAX_ORDER_LO; > -static bool slab_max_order_set __initdata; > - > -static inline void *index_to_obj(struct kmem_cache *cache, > - const struct slab *slab, unsigned int idx) > -{ > - return slab->s_mem + cache->size * idx; > -} > - > -#define BOOT_CPUCACHE_ENTRIES 1 > -/* internal cache of cache description objs */ > -static struct kmem_cache kmem_cache_boot = { > - .batchcount = 1, > - .limit = BOOT_CPUCACHE_ENTRIES, > - .shared = 1, > - .size = sizeof(struct kmem_cache), > - .name = "kmem_cache", > -}; > - > -static DEFINE_PER_CPU(struct delayed_work, slab_reap_work); > - > -static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) > -{ > - return this_cpu_ptr(cachep->cpu_cache); > -} > - > -/* > - * Calculate the number of objects and left-over bytes for a given buffer size. > - */ > -static unsigned int cache_estimate(unsigned long gfporder, size_t buffer_size, > - slab_flags_t flags, size_t *left_over) > -{ > - unsigned int num; > - size_t slab_size = PAGE_SIZE << gfporder; > - > - /* > - * The slab management structure can be either off the slab or > - * on it. For the latter case, the memory allocated for a > - * slab is used for: > - * > - * - @buffer_size bytes for each object > - * - One freelist_idx_t for each object > - * > - * We don't need to consider alignment of freelist because > - * freelist will be at the end of slab page. The objects will be > - * at the correct alignment. > - * > - * If the slab management structure is off the slab, then the > - * alignment will already be calculated into the size. Because > - * the slabs are all pages aligned, the objects will be at the > - * correct alignment when allocated. > - */ > - if (flags & (CFLGS_OBJFREELIST_SLAB | CFLGS_OFF_SLAB)) { > - num = slab_size / buffer_size; > - *left_over = slab_size % buffer_size; > - } else { > - num = slab_size / (buffer_size + sizeof(freelist_idx_t)); > - *left_over = slab_size % > - (buffer_size + sizeof(freelist_idx_t)); > - } > - > - return num; > -} > - > -#if DEBUG > -#define slab_error(cachep, msg) __slab_error(__func__, cachep, msg) > - > -static void __slab_error(const char *function, struct kmem_cache *cachep, > - char *msg) > -{ > - pr_err("slab error in %s(): cache `%s': %s\n", > - function, cachep->name, msg); > - dump_stack(); > - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -} > -#endif > - > -/* > - * By default on NUMA we use alien caches to stage the freeing of > - * objects allocated from other nodes. This causes massive memory > - * inefficiencies when using fake NUMA setup to split memory into a > - * large number of small nodes, so it can be disabled on the command > - * line > - */ > - > -static int use_alien_caches __read_mostly = 1; > -static int __init noaliencache_setup(char *s) > -{ > - use_alien_caches = 0; > - return 1; > -} > -__setup("noaliencache", noaliencache_setup); > - > -static int __init slab_max_order_setup(char *str) > -{ > - get_option(&str, &slab_max_order); > - slab_max_order = slab_max_order < 0 ? 0 : > - min(slab_max_order, MAX_ORDER - 1); > - slab_max_order_set = true; > - > - return 1; > -} > -__setup("slab_max_order=", slab_max_order_setup); > - > -#ifdef CONFIG_NUMA > -/* > - * Special reaping functions for NUMA systems called from cache_reap(). > - * These take care of doing round robin flushing of alien caches (containing > - * objects freed on different nodes from which they were allocated) and the > - * flushing of remote pcps by calling drain_node_pages. > - */ > -static DEFINE_PER_CPU(unsigned long, slab_reap_node); > - > -static void init_reap_node(int cpu) > -{ > - per_cpu(slab_reap_node, cpu) = next_node_in(cpu_to_mem(cpu), > - node_online_map); > -} > - > -static void next_reap_node(void) > -{ > - int node = __this_cpu_read(slab_reap_node); > - > - node = next_node_in(node, node_online_map); > - __this_cpu_write(slab_reap_node, node); > -} > - > -#else > -#define init_reap_node(cpu) do { } while (0) > -#define next_reap_node(void) do { } while (0) > -#endif > - > -/* > - * Initiate the reap timer running on the target CPU. We run at around 1 to 2Hz > - * via the workqueue/eventd. > - * Add the CPU number into the expiration time to minimize the possibility of > - * the CPUs getting into lockstep and contending for the global cache chain > - * lock. > - */ > -static void start_cpu_timer(int cpu) > -{ > - struct delayed_work *reap_work = &per_cpu(slab_reap_work, cpu); > - > - if (reap_work->work.func == NULL) { > - init_reap_node(cpu); > - INIT_DEFERRABLE_WORK(reap_work, cache_reap); > - schedule_delayed_work_on(cpu, reap_work, > - __round_jiffies_relative(HZ, cpu)); > - } > -} > - > -static void init_arraycache(struct array_cache *ac, int limit, int batch) > -{ > - if (ac) { > - ac->avail = 0; > - ac->limit = limit; > - ac->batchcount = batch; > - ac->touched = 0; > - } > -} > - > -static struct array_cache *alloc_arraycache(int node, int entries, > - int batchcount, gfp_t gfp) > -{ > - size_t memsize = sizeof(void *) * entries + sizeof(struct array_cache); > - struct array_cache *ac = NULL; > - > - ac = kmalloc_node(memsize, gfp, node); > - /* > - * The array_cache structures contain pointers to free object. > - * However, when such objects are allocated or transferred to another > - * cache the pointers are not cleared and they could be counted as > - * valid references during a kmemleak scan. Therefore, kmemleak must > - * not scan such objects. > - */ > - kmemleak_no_scan(ac); > - init_arraycache(ac, entries, batchcount); > - return ac; > -} > - > -static noinline void cache_free_pfmemalloc(struct kmem_cache *cachep, > - struct slab *slab, void *objp) > -{ > - struct kmem_cache_node *n; > - int slab_node; > - LIST_HEAD(list); > - > - slab_node = slab_nid(slab); > - n = get_node(cachep, slab_node); > - > - raw_spin_lock(&n->list_lock); > - free_block(cachep, &objp, 1, slab_node, &list); > - raw_spin_unlock(&n->list_lock); > - > - slabs_destroy(cachep, &list); > -} > - > -/* > - * Transfer objects in one arraycache to another. > - * Locking must be handled by the caller. > - * > - * Return the number of entries transferred. > - */ > -static int transfer_objects(struct array_cache *to, > - struct array_cache *from, unsigned int max) > -{ > - /* Figure out how many entries to transfer */ > - int nr = min3(from->avail, max, to->limit - to->avail); > - > - if (!nr) > - return 0; > - > - memcpy(to->entry + to->avail, from->entry + from->avail - nr, > - sizeof(void *) *nr); > - > - from->avail -= nr; > - to->avail += nr; > - return nr; > -} > - > -/* &alien->lock must be held by alien callers. */ > -static __always_inline void __free_one(struct array_cache *ac, void *objp) > -{ > - /* Avoid trivial double-free. */ > - if (IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && > - WARN_ON_ONCE(ac->avail > 0 && ac->entry[ac->avail - 1] == objp)) > - return; > - ac->entry[ac->avail++] = objp; > -} > - > -#ifndef CONFIG_NUMA > - > -#define drain_alien_cache(cachep, alien) do { } while (0) > -#define reap_alien(cachep, n) do { } while (0) > - > -static inline struct alien_cache **alloc_alien_cache(int node, > - int limit, gfp_t gfp) > -{ > - return NULL; > -} > - > -static inline void free_alien_cache(struct alien_cache **ac_ptr) > -{ > -} > - > -static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) > -{ > - return 0; > -} > - > -static inline gfp_t gfp_exact_node(gfp_t flags) > -{ > - return flags & ~__GFP_NOFAIL; > -} > - > -#else /* CONFIG_NUMA */ > - > -static struct alien_cache *__alloc_alien_cache(int node, int entries, > - int batch, gfp_t gfp) > -{ > - size_t memsize = sizeof(void *) * entries + sizeof(struct alien_cache); > - struct alien_cache *alc = NULL; > - > - alc = kmalloc_node(memsize, gfp, node); > - if (alc) { > - kmemleak_no_scan(alc); > - init_arraycache(&alc->ac, entries, batch); > - spin_lock_init(&alc->lock); > - } > - return alc; > -} > - > -static struct alien_cache **alloc_alien_cache(int node, int limit, gfp_t gfp) > -{ > - struct alien_cache **alc_ptr; > - int i; > - > - if (limit > 1) > - limit = 12; > - alc_ptr = kcalloc_node(nr_node_ids, sizeof(void *), gfp, node); > - if (!alc_ptr) > - return NULL; > - > - for_each_node(i) { > - if (i == node || !node_online(i)) > - continue; > - alc_ptr[i] = __alloc_alien_cache(node, limit, 0xbaadf00d, gfp); > - if (!alc_ptr[i]) { > - for (i--; i >= 0; i--) > - kfree(alc_ptr[i]); > - kfree(alc_ptr); > - return NULL; > - } > - } > - return alc_ptr; > -} > - > -static void free_alien_cache(struct alien_cache **alc_ptr) > -{ > - int i; > - > - if (!alc_ptr) > - return; > - for_each_node(i) > - kfree(alc_ptr[i]); > - kfree(alc_ptr); > -} > - > -static void __drain_alien_cache(struct kmem_cache *cachep, > - struct array_cache *ac, int node, > - struct list_head *list) > -{ > - struct kmem_cache_node *n = get_node(cachep, node); > - > - if (ac->avail) { > - raw_spin_lock(&n->list_lock); > - /* > - * Stuff objects into the remote nodes shared array first. > - * That way we could avoid the overhead of putting the objects > - * into the free lists and getting them back later. > - */ > - if (n->shared) > - transfer_objects(n->shared, ac, ac->limit); > - > - free_block(cachep, ac->entry, ac->avail, node, list); > - ac->avail = 0; > - raw_spin_unlock(&n->list_lock); > - } > -} > - > -/* > - * Called from cache_reap() to regularly drain alien caches round robin. > - */ > -static void reap_alien(struct kmem_cache *cachep, struct kmem_cache_node *n) > -{ > - int node = __this_cpu_read(slab_reap_node); > - > - if (n->alien) { > - struct alien_cache *alc = n->alien[node]; > - struct array_cache *ac; > - > - if (alc) { > - ac = &alc->ac; > - if (ac->avail && spin_trylock_irq(&alc->lock)) { > - LIST_HEAD(list); > - > - __drain_alien_cache(cachep, ac, node, &list); > - spin_unlock_irq(&alc->lock); > - slabs_destroy(cachep, &list); > - } > - } > - } > -} > - > -static void drain_alien_cache(struct kmem_cache *cachep, > - struct alien_cache **alien) > -{ > - int i = 0; > - struct alien_cache *alc; > - struct array_cache *ac; > - unsigned long flags; > - > - for_each_online_node(i) { > - alc = alien[i]; > - if (alc) { > - LIST_HEAD(list); > - > - ac = &alc->ac; > - spin_lock_irqsave(&alc->lock, flags); > - __drain_alien_cache(cachep, ac, i, &list); > - spin_unlock_irqrestore(&alc->lock, flags); > - slabs_destroy(cachep, &list); > - } > - } > -} > - > -static int __cache_free_alien(struct kmem_cache *cachep, void *objp, > - int node, int slab_node) > -{ > - struct kmem_cache_node *n; > - struct alien_cache *alien = NULL; > - struct array_cache *ac; > - LIST_HEAD(list); > - > - n = get_node(cachep, node); > - STATS_INC_NODEFREES(cachep); > - if (n->alien && n->alien[slab_node]) { > - alien = n->alien[slab_node]; > - ac = &alien->ac; > - spin_lock(&alien->lock); > - if (unlikely(ac->avail == ac->limit)) { > - STATS_INC_ACOVERFLOW(cachep); > - __drain_alien_cache(cachep, ac, slab_node, &list); > - } > - __free_one(ac, objp); > - spin_unlock(&alien->lock); > - slabs_destroy(cachep, &list); > - } else { > - n = get_node(cachep, slab_node); > - raw_spin_lock(&n->list_lock); > - free_block(cachep, &objp, 1, slab_node, &list); > - raw_spin_unlock(&n->list_lock); > - slabs_destroy(cachep, &list); > - } > - return 1; > -} > - > -static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) > -{ > - int slab_node = slab_nid(virt_to_slab(objp)); > - int node = numa_mem_id(); > - /* > - * Make sure we are not freeing an object from another node to the array > - * cache on this cpu. > - */ > - if (likely(node == slab_node)) > - return 0; > - > - return __cache_free_alien(cachep, objp, node, slab_node); > -} > - > -/* > - * Construct gfp mask to allocate from a specific node but do not reclaim or > - * warn about failures. > - */ > -static inline gfp_t gfp_exact_node(gfp_t flags) > -{ > - return (flags | __GFP_THISNODE | __GFP_NOWARN) & ~(__GFP_RECLAIM|__GFP_NOFAIL); > -} > -#endif > - > -static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp) > -{ > - struct kmem_cache_node *n; > - > - /* > - * Set up the kmem_cache_node for cpu before we can > - * begin anything. Make sure some other cpu on this > - * node has not already allocated this > - */ > - n = get_node(cachep, node); > - if (n) { > - raw_spin_lock_irq(&n->list_lock); > - n->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount + > - cachep->num; > - raw_spin_unlock_irq(&n->list_lock); > - > - return 0; > - } > - > - n = kmalloc_node(sizeof(struct kmem_cache_node), gfp, node); > - if (!n) > - return -ENOMEM; > - > - kmem_cache_node_init(n); > - n->next_reap = jiffies + REAPTIMEOUT_NODE + > - ((unsigned long)cachep) % REAPTIMEOUT_NODE; > - > - n->free_limit = > - (1 + nr_cpus_node(node)) * cachep->batchcount + cachep->num; > - > - /* > - * The kmem_cache_nodes don't come and go as CPUs > - * come and go. slab_mutex provides sufficient > - * protection here. > - */ > - cachep->node[node] = n; > - > - return 0; > -} > - > -#if defined(CONFIG_NUMA) || defined(CONFIG_SMP) > -/* > - * Allocates and initializes node for a node on each slab cache, used for > - * either memory or cpu hotplug. If memory is being hot-added, the kmem_cache_node > - * will be allocated off-node since memory is not yet online for the new node. > - * When hotplugging memory or a cpu, existing nodes are not replaced if > - * already in use. > - * > - * Must hold slab_mutex. > - */ > -static int init_cache_node_node(int node) > -{ > - int ret; > - struct kmem_cache *cachep; > - > - list_for_each_entry(cachep, &slab_caches, list) { > - ret = init_cache_node(cachep, node, GFP_KERNEL); > - if (ret) > - return ret; > - } > - > - return 0; > -} > -#endif > - > -static int setup_kmem_cache_node(struct kmem_cache *cachep, > - int node, gfp_t gfp, bool force_change) > -{ > - int ret = -ENOMEM; > - struct kmem_cache_node *n; > - struct array_cache *old_shared = NULL; > - struct array_cache *new_shared = NULL; > - struct alien_cache **new_alien = NULL; > - LIST_HEAD(list); > - > - if (use_alien_caches) { > - new_alien = alloc_alien_cache(node, cachep->limit, gfp); > - if (!new_alien) > - goto fail; > - } > - > - if (cachep->shared) { > - new_shared = alloc_arraycache(node, > - cachep->shared * cachep->batchcount, 0xbaadf00d, gfp); > - if (!new_shared) > - goto fail; > - } > - > - ret = init_cache_node(cachep, node, gfp); > - if (ret) > - goto fail; > - > - n = get_node(cachep, node); > - raw_spin_lock_irq(&n->list_lock); > - if (n->shared && force_change) { > - free_block(cachep, n->shared->entry, > - n->shared->avail, node, &list); > - n->shared->avail = 0; > - } > - > - if (!n->shared || force_change) { > - old_shared = n->shared; > - n->shared = new_shared; > - new_shared = NULL; > - } > - > - if (!n->alien) { > - n->alien = new_alien; > - new_alien = NULL; > - } > - > - raw_spin_unlock_irq(&n->list_lock); > - slabs_destroy(cachep, &list); > - > - /* > - * To protect lockless access to n->shared during irq disabled context. > - * If n->shared isn't NULL in irq disabled context, accessing to it is > - * guaranteed to be valid until irq is re-enabled, because it will be > - * freed after synchronize_rcu(). > - */ > - if (old_shared && force_change) > - synchronize_rcu(); > - > -fail: > - kfree(old_shared); > - kfree(new_shared); > - free_alien_cache(new_alien); > - > - return ret; > -} > - > -#ifdef CONFIG_SMP > - > -static void cpuup_canceled(long cpu) > -{ > - struct kmem_cache *cachep; > - struct kmem_cache_node *n = NULL; > - int node = cpu_to_mem(cpu); > - const struct cpumask *mask = cpumask_of_node(node); > - > - list_for_each_entry(cachep, &slab_caches, list) { > - struct array_cache *nc; > - struct array_cache *shared; > - struct alien_cache **alien; > - LIST_HEAD(list); > - > - n = get_node(cachep, node); > - if (!n) > - continue; > - > - raw_spin_lock_irq(&n->list_lock); > - > - /* Free limit for this kmem_cache_node */ > - n->free_limit -= cachep->batchcount; > - > - /* cpu is dead; no one can alloc from it. */ > - nc = per_cpu_ptr(cachep->cpu_cache, cpu); > - free_block(cachep, nc->entry, nc->avail, node, &list); > - nc->avail = 0; > - > - if (!cpumask_empty(mask)) { > - raw_spin_unlock_irq(&n->list_lock); > - goto free_slab; > - } > - > - shared = n->shared; > - if (shared) { > - free_block(cachep, shared->entry, > - shared->avail, node, &list); > - n->shared = NULL; > - } > - > - alien = n->alien; > - n->alien = NULL; > - > - raw_spin_unlock_irq(&n->list_lock); > - > - kfree(shared); > - if (alien) { > - drain_alien_cache(cachep, alien); > - free_alien_cache(alien); > - } > - > -free_slab: > - slabs_destroy(cachep, &list); > - } > - /* > - * In the previous loop, all the objects were freed to > - * the respective cache's slabs, now we can go ahead and > - * shrink each nodelist to its limit. > - */ > - list_for_each_entry(cachep, &slab_caches, list) { > - n = get_node(cachep, node); > - if (!n) > - continue; > - drain_freelist(cachep, n, INT_MAX); > - } > -} > - > -static int cpuup_prepare(long cpu) > -{ > - struct kmem_cache *cachep; > - int node = cpu_to_mem(cpu); > - int err; > - > - /* > - * We need to do this right in the beginning since > - * alloc_arraycache's are going to use this list. > - * kmalloc_node allows us to add the slab to the right > - * kmem_cache_node and not this cpu's kmem_cache_node > - */ > - err = init_cache_node_node(node); > - if (err < 0) > - goto bad; > - > - /* > - * Now we can go ahead with allocating the shared arrays and > - * array caches > - */ > - list_for_each_entry(cachep, &slab_caches, list) { > - err = setup_kmem_cache_node(cachep, node, GFP_KERNEL, false); > - if (err) > - goto bad; > - } > - > - return 0; > -bad: > - cpuup_canceled(cpu); > - return -ENOMEM; > -} > - > -int slab_prepare_cpu(unsigned int The slab allocator is very core and very important to the Linux kernel. After the patch is merged into the mainline, it will have a very profound impact on the development of the Linux kernel.
On Sun, Apr 02, 2023 at 05:09:14PM +0800, éƒè¾‰ wrote: > On 4/1/23 5:46 PM, Vlastimil Babka wrote: > > As the SLOB removal is on track and the SLAB removal is planned, I have > > realized - why should we stop there and not remove also SLUB? What's a > > slab allocator good for in 2023? The RAM sizes are getting larger and > > the modules cheaper [1]. The object constructor trick was perhaps > > interesting in 1994, but not with contemporary CPUs. So all the slab > > allocator does today is just adding an unnecessary layer of complexity > > over the page allocator. > > The slab allocator is very core and very important to the Linux kernel. > After the patch is merged into the mainline, it will have a very profound > impact on the development of the Linux kernel. https://en.wikipedia.org/wiki/April_Fools%27_Day
On Sun, 2 Apr 2023, 13:04 Matthew Wilcox, <willy@infradead.org> wrote: > On Sun, Apr 02, 2023 at 05:09:14PM +0800, éƒè¾‰ wrote: > > On 4/1/23 5:46 PM, Vlastimil Babka wrote: > > > As the SLOB removal is on track and the SLAB removal is planned, I have > > > realized - why should we stop there and not remove also SLUB? What's a > > > slab allocator good for in 2023? The RAM sizes are getting larger and > > > the modules cheaper [1]. The object constructor trick was perhaps > > > interesting in 1994, but not with contemporary CPUs. So all the slab > > > allocator does today is just adding an unnecessary layer of complexity > > > over the page allocator. > > > > The slab allocator is very core and very important to the Linux kernel. > > After the patch is merged into the mainline, it will have a very profound > > impact on the development of the Linux kernel. > > https://en.wikipedia.org/wiki/April_Fools%27_Day Wow! The most interesting implication of this "patch" is that you noticed that some people may actually need the link above to be able to distinguish between foolishness and reality... Thanks :-) Fabio
On lunedì 3 aprile 2023 05:51:42 CEST Fabio M. De Francesco wrote: > On Sun, 2 Apr 2023, 13:04 Matthew Wilcox, <willy@infradead.org> wrote: > > On Sun, Apr 02, 2023 at 05:09:14PM +0800, éƒè¾‰ wrote: > > > On 4/1/23 5:46 PM, Vlastimil Babka wrote: > > > > As the SLOB removal is on track and the SLAB removal is planned, I have > > > > realized - why should we stop there and not remove also SLUB? What's a > > > > slab allocator good for in 2023? The RAM sizes are getting larger and > > > > the modules cheaper [1]. The object constructor trick was perhaps > > > > interesting in 1994, but not with contemporary CPUs. So all the slab > > > > allocator does today is just adding an unnecessary layer of complexity > > > > over the page allocator. > > > > > > The slab allocator is very core and very important to the Linux kernel. > > > After the patch is merged into the mainline, it will have a very profound > > > impact on the development of the Linux kernel. > > > > https://en.wikipedia.org/wiki/April_Fools%27_Day > > Wow! > > The most interesting implication of this "patch" is that you noticed that > some people may actually need the link above to be able to distinguish > between foolishness and reality... > > Thanks :-) > > Fabio Ah, I was so shocked that didn't realize was responding with the GMail app from the tablet... :-) Fabio
On Mon, Apr 03, 2023 at 05:51:42AM +0200, Fabio M. De Francesco wrote: > On Sun, 2 Apr 2023, 13:04 Matthew Wilcox, <willy@infradead.org> wrote: > > > On Sun, Apr 02, 2023 at 05:09:14PM +0800, éƒè¾‰ wrote: > > > On 4/1/23 5:46 PM, Vlastimil Babka wrote: > > > > As the SLOB removal is on track and the SLAB removal is planned, I have > > > > realized - why should we stop there and not remove also SLUB? What's a > > > > slab allocator good for in 2023? The RAM sizes are getting larger and > > > > the modules cheaper [1]. The object constructor trick was perhaps > > > > interesting in 1994, but not with contemporary CPUs. So all the slab > > > > allocator does today is just adding an unnecessary layer of complexity > > > > over the page allocator. > > > > > > The slab allocator is very core and very important to the Linux kernel. > > > After the patch is merged into the mainline, it will have a very profound > > > impact on the development of the Linux kernel. > > > > https://en.wikipedia.org/wiki/April_Fools%27_Day > > > Wow! > > The most interesting implication of this "patch" is that you noticed that > some people may actually need the link above to be able to distinguish > between foolishness and reality... As the article says, this is a Western tradition, and we shouldn't assume that somebody from (I assume) China would be familiar with this particular foolishness ;-)
diff --git a/MAINTAINERS b/MAINTAINERS index 1dc8bd26b6cf..40b05ad03cd0 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -19183,21 +19183,6 @@ F: drivers/irqchip/irq-sl28cpld.c F: drivers/pwm/pwm-sl28cpld.c F: drivers/watchdog/sl28cpld_wdt.c -SLAB ALLOCATOR -M: Christoph Lameter <cl@linux.com> -M: Pekka Enberg <penberg@kernel.org> -M: David Rientjes <rientjes@google.com> -M: Joonsoo Kim <iamjoonsoo.kim@lge.com> -M: Andrew Morton <akpm@linux-foundation.org> -M: Vlastimil Babka <vbabka@suse.cz> -R: Roman Gushchin <roman.gushchin@linux.dev> -R: Hyeonggon Yoo <42.hyeyoo@gmail.com> -L: linux-mm@kvack.org -S: Maintained -T: git git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab.git -F: include/linux/sl?b*.h -F: mm/sl?b* - SLCAN CAN NETWORK DRIVER M: Dario Binacchi <dario.binacchi@amarulasolutions.com> L: linux-can@vger.kernel.org diff --git a/include/linux/slab.h b/include/linux/slab.h index 45af70315a94..61602d54b1d0 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -140,13 +140,14 @@ /* The following flags affect the page allocator grouping pages by mobility */ /* Objects are reclaimable */ -#ifndef CONFIG_SLUB_TINY #define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U) -#else -#define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0) -#endif #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */ +#define KMALLOC_NOT_NORMAL_BITS \ + (__GFP_RECLAIMABLE | \ + (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ + (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) + /* * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests. * @@ -278,38 +279,11 @@ static inline unsigned int arch_slab_minalign(void) * Kmalloc array related definitions */ -#ifdef CONFIG_SLAB -/* - * SLAB and SLUB directly allocates requests fitting in to an order-1 page - * (PAGE_SIZE*2). Larger requests are passed to the page allocator. - */ -#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) -#ifndef KMALLOC_SHIFT_LOW -#define KMALLOC_SHIFT_LOW 5 -#endif -#endif - -#ifdef CONFIG_SLUB -#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) -#ifndef KMALLOC_SHIFT_LOW -#define KMALLOC_SHIFT_LOW 3 -#endif -#endif - -#ifdef CONFIG_SLOB -/* - * SLOB passes all requests larger than one page to the page allocator. - * No kmalloc array is necessary since objects of different sizes can - * be allocated from the same page. - */ #define KMALLOC_SHIFT_HIGH PAGE_SHIFT #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 3 #endif -#endif /* Maximum allocatable size */ #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX) @@ -336,130 +310,6 @@ static inline unsigned int arch_slab_minalign(void) #define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \ (KMALLOC_MIN_SIZE) : 16) -/* - * Whenever changing this, take care of that kmalloc_type() and - * create_kmalloc_caches() still work as intended. - * - * KMALLOC_NORMAL can contain only unaccounted objects whereas KMALLOC_CGROUP - * is for accounted but unreclaimable and non-dma objects. All the other - * kmem caches can have both accounted and unaccounted objects. - */ -enum kmalloc_cache_type { - KMALLOC_NORMAL = 0, -#ifndef CONFIG_ZONE_DMA - KMALLOC_DMA = KMALLOC_NORMAL, -#endif -#ifndef CONFIG_MEMCG_KMEM - KMALLOC_CGROUP = KMALLOC_NORMAL, -#endif -#ifdef CONFIG_SLUB_TINY - KMALLOC_RECLAIM = KMALLOC_NORMAL, -#else - KMALLOC_RECLAIM, -#endif -#ifdef CONFIG_ZONE_DMA - KMALLOC_DMA, -#endif -#ifdef CONFIG_MEMCG_KMEM - KMALLOC_CGROUP, -#endif - NR_KMALLOC_TYPES -}; - -#ifndef CONFIG_SLOB -extern struct kmem_cache * -kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1]; - -/* - * Define gfp bits that should not be set for KMALLOC_NORMAL. - */ -#define KMALLOC_NOT_NORMAL_BITS \ - (__GFP_RECLAIMABLE | \ - (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ - (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) - -static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) -{ - /* - * The most common case is KMALLOC_NORMAL, so test for it - * with a single branch for all the relevant flags. - */ - if (likely((flags & KMALLOC_NOT_NORMAL_BITS) == 0)) - return KMALLOC_NORMAL; - - /* - * At least one of the flags has to be set. Their priorities in - * decreasing order are: - * 1) __GFP_DMA - * 2) __GFP_RECLAIMABLE - * 3) __GFP_ACCOUNT - */ - if (IS_ENABLED(CONFIG_ZONE_DMA) && (flags & __GFP_DMA)) - return KMALLOC_DMA; - if (!IS_ENABLED(CONFIG_MEMCG_KMEM) || (flags & __GFP_RECLAIMABLE)) - return KMALLOC_RECLAIM; - else - return KMALLOC_CGROUP; -} - -/* - * Figure out which kmalloc slab an allocation of a certain size - * belongs to. - * 0 = zero alloc - * 1 = 65 .. 96 bytes - * 2 = 129 .. 192 bytes - * n = 2^(n-1)+1 .. 2^n - * - * Note: __kmalloc_index() is compile-time optimized, and not runtime optimized; - * typical usage is via kmalloc_index() and therefore evaluated at compile-time. - * Callers where !size_is_constant should only be test modules, where runtime - * overheads of __kmalloc_index() can be tolerated. Also see kmalloc_slab(). - */ -static __always_inline unsigned int __kmalloc_index(size_t size, - bool size_is_constant) -{ - if (!size) - return 0; - - if (size <= KMALLOC_MIN_SIZE) - return KMALLOC_SHIFT_LOW; - - if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96) - return 1; - if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192) - return 2; - if (size <= 8) return 3; - if (size <= 16) return 4; - if (size <= 32) return 5; - if (size <= 64) return 6; - if (size <= 128) return 7; - if (size <= 256) return 8; - if (size <= 512) return 9; - if (size <= 1024) return 10; - if (size <= 2 * 1024) return 11; - if (size <= 4 * 1024) return 12; - if (size <= 8 * 1024) return 13; - if (size <= 16 * 1024) return 14; - if (size <= 32 * 1024) return 15; - if (size <= 64 * 1024) return 16; - if (size <= 128 * 1024) return 17; - if (size <= 256 * 1024) return 18; - if (size <= 512 * 1024) return 19; - if (size <= 1024 * 1024) return 20; - if (size <= 2 * 1024 * 1024) return 21; - - if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant) - BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()"); - else - BUG(); - - /* Will never be reached. Needed because the compiler may complain */ - return -1; -} -static_assert(PAGE_SHIFT <= 20); -#define kmalloc_index(s) __kmalloc_index(s, true) -#endif /* !CONFIG_SLOB */ - void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __alloc_size(1); /** @@ -567,57 +417,15 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) __assume_page_align * Try really hard to succeed the allocation but fail * eventually. */ -#ifndef CONFIG_SLOB -static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) -{ - if (__builtin_constant_p(size) && size) { - unsigned int index; - - if (size > KMALLOC_MAX_CACHE_SIZE) - return kmalloc_large(size, flags); - - index = kmalloc_index(size); - return kmalloc_trace( - kmalloc_caches[kmalloc_type(flags)][index], - flags, size); - } - return __kmalloc(size, flags); -} -#else static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) { - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) - return kmalloc_large(size, flags); - - return __kmalloc(size, flags); + return kmalloc_large(size, flags); } -#endif -#ifndef CONFIG_SLOB static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) { - if (__builtin_constant_p(size) && size) { - unsigned int index; - - if (size > KMALLOC_MAX_CACHE_SIZE) - return kmalloc_large_node(size, flags, node); - - index = kmalloc_index(size); - return kmalloc_node_trace( - kmalloc_caches[kmalloc_type(flags)][index], - flags, node, size); - } - return __kmalloc_node(size, flags, node); + return kmalloc_large_node(size, flags, node); } -#else -static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) -{ - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) - return kmalloc_large_node(size, flags, node); - - return __kmalloc_node(size, flags, node); -} -#endif /** * kmalloc_array - allocate memory for an array. @@ -785,12 +593,7 @@ size_t kmalloc_size_roundup(size_t size); void __init kmem_cache_init_late(void); -#if defined(CONFIG_SMP) && defined(CONFIG_SLAB) -int slab_prepare_cpu(unsigned int cpu); -int slab_dead_cpu(unsigned int cpu); -#else #define slab_prepare_cpu NULL #define slab_dead_cpu NULL -#endif #endif /* _LINUX_SLAB_H */ diff --git a/include/linux/slab_def.h b/include/linux/slab_def.h deleted file mode 100644 index a61e7d55d0d3..000000000000 --- a/include/linux/slab_def.h +++ /dev/null @@ -1,124 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#ifndef _LINUX_SLAB_DEF_H -#define _LINUX_SLAB_DEF_H - -#include <linux/kfence.h> -#include <linux/reciprocal_div.h> - -/* - * Definitions unique to the original Linux SLAB allocator. - */ - -struct kmem_cache { - struct array_cache __percpu *cpu_cache; - -/* 1) Cache tunables. Protected by slab_mutex */ - unsigned int batchcount; - unsigned int limit; - unsigned int shared; - - unsigned int size; - struct reciprocal_value reciprocal_buffer_size; -/* 2) touched by every alloc & free from the backend */ - - slab_flags_t flags; /* constant flags */ - unsigned int num; /* # of objs per slab */ - -/* 3) cache_grow/shrink */ - /* order of pgs per slab (2^n) */ - unsigned int gfporder; - - /* force GFP flags, e.g. GFP_DMA */ - gfp_t allocflags; - - size_t colour; /* cache colouring range */ - unsigned int colour_off; /* colour offset */ - unsigned int freelist_size; - - /* constructor func */ - void (*ctor)(void *obj); - -/* 4) cache creation/removal */ - const char *name; - struct list_head list; - int refcount; - int object_size; - int align; - -/* 5) statistics */ -#ifdef CONFIG_DEBUG_SLAB - unsigned long num_active; - unsigned long num_allocations; - unsigned long high_mark; - unsigned long grown; - unsigned long reaped; - unsigned long errors; - unsigned long max_freeable; - unsigned long node_allocs; - unsigned long node_frees; - unsigned long node_overflow; - atomic_t allochit; - atomic_t allocmiss; - atomic_t freehit; - atomic_t freemiss; - - /* - * If debugging is enabled, then the allocator can add additional - * fields and/or padding to every object. 'size' contains the total - * object size including these internal fields, while 'obj_offset' - * and 'object_size' contain the offset to the user object and its - * size. - */ - int obj_offset; -#endif /* CONFIG_DEBUG_SLAB */ - -#ifdef CONFIG_KASAN_GENERIC - struct kasan_cache kasan_info; -#endif - -#ifdef CONFIG_SLAB_FREELIST_RANDOM - unsigned int *random_seq; -#endif - -#ifdef CONFIG_HARDENED_USERCOPY - unsigned int useroffset; /* Usercopy region offset */ - unsigned int usersize; /* Usercopy region size */ -#endif - - struct kmem_cache_node *node[MAX_NUMNODES]; -}; - -static inline void *nearest_obj(struct kmem_cache *cache, const struct slab *slab, - void *x) -{ - void *object = x - (x - slab->s_mem) % cache->size; - void *last_object = slab->s_mem + (cache->num - 1) * cache->size; - - if (unlikely(object > last_object)) - return last_object; - else - return object; -} - -/* - * We want to avoid an expensive divide : (offset / cache->size) - * Using the fact that size is a constant for a particular cache, - * we can replace (offset / cache->size) by - * reciprocal_divide(offset, cache->reciprocal_buffer_size) - */ -static inline unsigned int obj_to_index(const struct kmem_cache *cache, - const struct slab *slab, void *obj) -{ - u32 offset = (obj - slab->s_mem); - return reciprocal_divide(offset, cache->reciprocal_buffer_size); -} - -static inline int objs_per_slab(const struct kmem_cache *cache, - const struct slab *slab) -{ - if (is_kfence_address(slab_address(slab))) - return 1; - return cache->num; -} - -#endif /* _LINUX_SLAB_DEF_H */ diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h deleted file mode 100644 index f6df03f934e5..000000000000 --- a/include/linux/slub_def.h +++ /dev/null @@ -1,198 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#ifndef _LINUX_SLUB_DEF_H -#define _LINUX_SLUB_DEF_H - -/* - * SLUB : A Slab allocator without object queues. - * - * (C) 2007 SGI, Christoph Lameter - */ -#include <linux/kfence.h> -#include <linux/kobject.h> -#include <linux/reciprocal_div.h> -#include <linux/local_lock.h> - -enum stat_item { - ALLOC_FASTPATH, /* Allocation from cpu slab */ - ALLOC_SLOWPATH, /* Allocation by getting a new cpu slab */ - FREE_FASTPATH, /* Free to cpu slab */ - FREE_SLOWPATH, /* Freeing not to cpu slab */ - FREE_FROZEN, /* Freeing to frozen slab */ - FREE_ADD_PARTIAL, /* Freeing moves slab to partial list */ - FREE_REMOVE_PARTIAL, /* Freeing removes last object */ - ALLOC_FROM_PARTIAL, /* Cpu slab acquired from node partial list */ - ALLOC_SLAB, /* Cpu slab acquired from page allocator */ - ALLOC_REFILL, /* Refill cpu slab from slab freelist */ - ALLOC_NODE_MISMATCH, /* Switching cpu slab */ - FREE_SLAB, /* Slab freed to the page allocator */ - CPUSLAB_FLUSH, /* Abandoning of the cpu slab */ - DEACTIVATE_FULL, /* Cpu slab was full when deactivated */ - DEACTIVATE_EMPTY, /* Cpu slab was empty when deactivated */ - DEACTIVATE_TO_HEAD, /* Cpu slab was moved to the head of partials */ - DEACTIVATE_TO_TAIL, /* Cpu slab was moved to the tail of partials */ - DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */ - DEACTIVATE_BYPASS, /* Implicit deactivation */ - ORDER_FALLBACK, /* Number of times fallback was necessary */ - CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */ - CMPXCHG_DOUBLE_FAIL, /* Number of times that cmpxchg double did not match */ - CPU_PARTIAL_ALLOC, /* Used cpu partial on alloc */ - CPU_PARTIAL_FREE, /* Refill cpu partial on free */ - CPU_PARTIAL_NODE, /* Refill cpu partial from node partial */ - CPU_PARTIAL_DRAIN, /* Drain cpu partial to node partial */ - NR_SLUB_STAT_ITEMS }; - -#ifndef CONFIG_SLUB_TINY -/* - * When changing the layout, make sure freelist and tid are still compatible - * with this_cpu_cmpxchg_double() alignment requirements. - */ -struct kmem_cache_cpu { - void **freelist; /* Pointer to next available object */ - unsigned long tid; /* Globally unique transaction id */ - struct slab *slab; /* The slab from which we are allocating */ -#ifdef CONFIG_SLUB_CPU_PARTIAL - struct slab *partial; /* Partially allocated frozen slabs */ -#endif - local_lock_t lock; /* Protects the fields above */ -#ifdef CONFIG_SLUB_STATS - unsigned stat[NR_SLUB_STAT_ITEMS]; -#endif -}; -#endif /* CONFIG_SLUB_TINY */ - -#ifdef CONFIG_SLUB_CPU_PARTIAL -#define slub_percpu_partial(c) ((c)->partial) - -#define slub_set_percpu_partial(c, p) \ -({ \ - slub_percpu_partial(c) = (p)->next; \ -}) - -#define slub_percpu_partial_read_once(c) READ_ONCE(slub_percpu_partial(c)) -#else -#define slub_percpu_partial(c) NULL - -#define slub_set_percpu_partial(c, p) - -#define slub_percpu_partial_read_once(c) NULL -#endif // CONFIG_SLUB_CPU_PARTIAL - -/* - * Word size structure that can be atomically updated or read and that - * contains both the order and the number of objects that a slab of the - * given order would contain. - */ -struct kmem_cache_order_objects { - unsigned int x; -}; - -/* - * Slab cache management. - */ -struct kmem_cache { -#ifndef CONFIG_SLUB_TINY - struct kmem_cache_cpu __percpu *cpu_slab; -#endif - /* Used for retrieving partial slabs, etc. */ - slab_flags_t flags; - unsigned long min_partial; - unsigned int size; /* The size of an object including metadata */ - unsigned int object_size;/* The size of an object without metadata */ - struct reciprocal_value reciprocal_size; - unsigned int offset; /* Free pointer offset */ -#ifdef CONFIG_SLUB_CPU_PARTIAL - /* Number of per cpu partial objects to keep around */ - unsigned int cpu_partial; - /* Number of per cpu partial slabs to keep around */ - unsigned int cpu_partial_slabs; -#endif - struct kmem_cache_order_objects oo; - - /* Allocation and freeing of slabs */ - struct kmem_cache_order_objects min; - gfp_t allocflags; /* gfp flags to use on each alloc */ - int refcount; /* Refcount for slab cache destroy */ - void (*ctor)(void *); - unsigned int inuse; /* Offset to metadata */ - unsigned int align; /* Alignment */ - unsigned int red_left_pad; /* Left redzone padding size */ - const char *name; /* Name (only for display!) */ - struct list_head list; /* List of slab caches */ -#ifdef CONFIG_SYSFS - struct kobject kobj; /* For sysfs */ -#endif -#ifdef CONFIG_SLAB_FREELIST_HARDENED - unsigned long random; -#endif - -#ifdef CONFIG_NUMA - /* - * Defragmentation by allocating from a remote node. - */ - unsigned int remote_node_defrag_ratio; -#endif - -#ifdef CONFIG_SLAB_FREELIST_RANDOM - unsigned int *random_seq; -#endif - -#ifdef CONFIG_KASAN_GENERIC - struct kasan_cache kasan_info; -#endif - -#ifdef CONFIG_HARDENED_USERCOPY - unsigned int useroffset; /* Usercopy region offset */ - unsigned int usersize; /* Usercopy region size */ -#endif - - struct kmem_cache_node *node[MAX_NUMNODES]; -}; - -#if defined(CONFIG_SYSFS) && !defined(CONFIG_SLUB_TINY) -#define SLAB_SUPPORTS_SYSFS -void sysfs_slab_unlink(struct kmem_cache *); -void sysfs_slab_release(struct kmem_cache *); -#else -static inline void sysfs_slab_unlink(struct kmem_cache *s) -{ -} -static inline void sysfs_slab_release(struct kmem_cache *s) -{ -} -#endif - -void *fixup_red_left(struct kmem_cache *s, void *p); - -static inline void *nearest_obj(struct kmem_cache *cache, const struct slab *slab, - void *x) { - void *object = x - (x - slab_address(slab)) % cache->size; - void *last_object = slab_address(slab) + - (slab->objects - 1) * cache->size; - void *result = (unlikely(object > last_object)) ? last_object : object; - - result = fixup_red_left(cache, result); - return result; -} - -/* Determine object index from a given position */ -static inline unsigned int __obj_to_index(const struct kmem_cache *cache, - void *addr, void *obj) -{ - return reciprocal_divide(kasan_reset_tag(obj) - addr, - cache->reciprocal_size); -} - -static inline unsigned int obj_to_index(const struct kmem_cache *cache, - const struct slab *slab, void *obj) -{ - if (is_kfence_address(obj)) - return 0; - return __obj_to_index(cache, slab_address(slab), obj); -} - -static inline int objs_per_slab(const struct kmem_cache *cache, - const struct slab *slab) -{ - return slab->objects; -} -#endif /* _LINUX_SLUB_DEF_H */ diff --git a/init/Kconfig b/init/Kconfig index 1fb5f313d18f..45be2eedf75c 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -973,7 +973,7 @@ config MEMCG config MEMCG_KMEM bool - depends on MEMCG && !SLOB + depends on MEMCG && BROKEN default y config BLK_CGROUP diff --git a/mm/Kconfig b/mm/Kconfig index 4751031f3f05..f07e81bca39e 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -210,134 +210,9 @@ config ZSMALLOC_CHAIN_SIZE For more information, see zsmalloc documentation. -menu "SLAB allocator options" - -choice - prompt "Choose SLAB allocator" - default SLUB - help - This option allows to select a slab allocator. - -config SLAB - bool "SLAB" - depends on !PREEMPT_RT - select HAVE_HARDENED_USERCOPY_ALLOCATOR - help - The regular slab allocator that is established and known to work - well in all environments. It organizes cache hot objects in - per cpu and per node queues. - -config SLUB - bool "SLUB (Unqueued Allocator)" - select HAVE_HARDENED_USERCOPY_ALLOCATOR - help - SLUB is a slab allocator that minimizes cache line usage - instead of managing queues of cached objects (SLAB approach). - Per cpu caching is realized using slabs of objects instead - of queues of objects. SLUB can use memory efficiently - and has enhanced diagnostics. SLUB is the default choice for - a slab allocator. - -config SLOB_DEPRECATED - depends on EXPERT - bool "SLOB (Simple Allocator - DEPRECATED)" - depends on !PREEMPT_RT - help - Deprecated and scheduled for removal in a few cycles. SLUB - recommended as replacement. CONFIG_SLUB_TINY can be considered - on systems with 16MB or less RAM. - - If you need SLOB to stay, please contact linux-mm@kvack.org and - people listed in the SLAB ALLOCATOR section of MAINTAINERS file, - with your use case. - - SLOB replaces the stock allocator with a drastically simpler - allocator. SLOB is generally more space efficient but - does not perform as well on large systems. - -endchoice - -config SLOB - bool - default y - depends on SLOB_DEPRECATED - -config SLUB_TINY - bool "Configure SLUB for minimal memory footprint" - depends on SLUB && EXPERT - select SLAB_MERGE_DEFAULT - help - Configures the SLUB allocator in a way to achieve minimal memory - footprint, sacrificing scalability, debugging and other features. - This is intended only for the smallest system that had used the - SLOB allocator and is not recommended for systems with more than - 16MB RAM. - - If unsure, say N. - -config SLAB_MERGE_DEFAULT - bool "Allow slab caches to be merged" - default y - depends on SLAB || SLUB - help - For reduced kernel memory fragmentation, slab caches can be - merged when they share the same size and other characteristics. - This carries a risk of kernel heap overflows being able to - overwrite objects from merged caches (and more easily control - cache layout), which makes such heap attacks easier to exploit - by attackers. By keeping caches unmerged, these kinds of exploits - can usually only damage objects in the same cache. To disable - merging at runtime, "slab_nomerge" can be passed on the kernel - command line. - -config SLAB_FREELIST_RANDOM - bool "Randomize slab freelist" - depends on SLAB || (SLUB && !SLUB_TINY) - help - Randomizes the freelist order used on creating new pages. This - security feature reduces the predictability of the kernel slab - allocator against heap overflows. - -config SLAB_FREELIST_HARDENED - bool "Harden slab freelist metadata" - depends on SLAB || (SLUB && !SLUB_TINY) - help - Many kernel heap attacks try to target slab cache metadata and - other infrastructure. This options makes minor performance - sacrifices to harden the kernel slab allocator against common - freelist exploit methods. Some slab implementations have more - sanity-checking than others. This option is most effective with - CONFIG_SLUB. - -config SLUB_STATS - default n - bool "Enable SLUB performance statistics" - depends on SLUB && SYSFS && !SLUB_TINY - help - SLUB statistics are useful to debug SLUBs allocation behavior in - order find ways to optimize the allocator. This should never be - enabled for production use since keeping statistics slows down - the allocator by a few percentage points. The slabinfo command - supports the determination of the most active slabs to figure - out which slabs are relevant to a particular load. - Try running: slabinfo -DA - -config SLUB_CPU_PARTIAL - default y - depends on SLUB && SMP && !SLUB_TINY - bool "SLUB per cpu partial cache" - help - Per cpu partial caches accelerate objects allocation and freeing - that is local to a processor at the price of more indeterminism - in the latency of the free. On overflow these caches will be cleared - which requires the taking of locks that may cause latency spikes. - Typically one would choose no for a realtime system. - -endmenu # SLAB allocator options - config SHUFFLE_PAGE_ALLOCATOR bool "Page allocator randomization" - default SLAB_FREELIST_RANDOM && ACPI_NUMA + default ACPI_NUMA help Randomization of the page allocator improves the average utilization of a direct-mapped memory-side-cache. See section @@ -345,10 +220,9 @@ config SHUFFLE_PAGE_ALLOCATOR 6.2a specification for an example of how a platform advertises the presence of a memory-side-cache. There are also incidental security benefits as it reduces the predictability of page - allocations to compliment SLAB_FREELIST_RANDOM, but the - default granularity of shuffling on the "MAX_ORDER - 1" i.e, - 10th order of pages is selected based on cache utilization - benefits on x86. + allocations, but the default granularity of shuffling on the + "MAX_ORDER - 1" i.e, 10th order of pages is selected based on + cache utilization benefits on x86. While the randomization improves cache utilization it may negatively impact workloads on platforms without a cache. For diff --git a/mm/Makefile b/mm/Makefile index 8e105e5b3e29..18b0bb245fc3 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -4,16 +4,12 @@ # KASAN_SANITIZE_slab_common.o := n -KASAN_SANITIZE_slab.o := n -KASAN_SANITIZE_slub.o := n KCSAN_SANITIZE_kmemleak.o := n # These produce frequent data race reports: most of them are due to races on # the same word but accesses to different bits of that word. Re-enable KCSAN # for these when we have more consensus on what to do about them. KCSAN_SANITIZE_slab_common.o := n -KCSAN_SANITIZE_slab.o := n -KCSAN_SANITIZE_slub.o := n KCSAN_SANITIZE_page_alloc.o := n # But enable explicit instrumentation for memory barriers. KCSAN_INSTRUMENT_BARRIERS := y @@ -22,9 +18,6 @@ KCSAN_INSTRUMENT_BARRIERS := y # flaky coverage that is not a function of syscall inputs. E.g. slab is out of # free pages, or a task is migrated between nodes. KCOV_INSTRUMENT_slab_common.o := n -KCOV_INSTRUMENT_slob.o := n -KCOV_INSTRUMENT_slab.o := n -KCOV_INSTRUMENT_slub.o := n KCOV_INSTRUMENT_page_alloc.o := n KCOV_INSTRUMENT_debug-pagealloc.o := n KCOV_INSTRUMENT_kmemleak.o := n @@ -81,12 +74,9 @@ obj-$(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP) += hugetlb_vmemmap.o obj-$(CONFIG_NUMA) += mempolicy.o obj-$(CONFIG_SPARSEMEM) += sparse.o obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o -obj-$(CONFIG_SLOB) += slob.o obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o obj-$(CONFIG_KSM) += ksm.o obj-$(CONFIG_PAGE_POISONING) += page_poison.o -obj-$(CONFIG_SLAB) += slab.o -obj-$(CONFIG_SLUB) += slub.o obj-$(CONFIG_KASAN) += kasan/ obj-$(CONFIG_KFENCE) += kfence/ obj-$(CONFIG_KMSAN) += kmsan/ diff --git a/mm/slab.c b/mm/slab.c deleted file mode 100644 index edbe722fb906..000000000000 --- a/mm/slab.c +++ /dev/null @@ -1,4046 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * linux/mm/slab.c - * Written by Mark Hemment, 1996/97. - * (markhe@nextd.demon.co.uk) - * - * kmem_cache_destroy() + some cleanup - 1999 Andrea Arcangeli - * - * Major cleanup, different bufctl logic, per-cpu arrays - * (c) 2000 Manfred Spraul - * - * Cleanup, make the head arrays unconditional, preparation for NUMA - * (c) 2002 Manfred Spraul - * - * An implementation of the Slab Allocator as described in outline in; - * UNIX Internals: The New Frontiers by Uresh Vahalia - * Pub: Prentice Hall ISBN 0-13-101908-2 - * or with a little more detail in; - * The Slab Allocator: An Object-Caching Kernel Memory Allocator - * Jeff Bonwick (Sun Microsystems). - * Presented at: USENIX Summer 1994 Technical Conference - * - * The memory is organized in caches, one cache for each object type. - * (e.g. inode_cache, dentry_cache, buffer_head, vm_area_struct) - * Each cache consists out of many slabs (they are small (usually one - * page long) and always contiguous), and each slab contains multiple - * initialized objects. - * - * This means, that your constructor is used only for newly allocated - * slabs and you must pass objects with the same initializations to - * kmem_cache_free. - * - * Each cache can only support one memory type (GFP_DMA, GFP_HIGHMEM, - * normal). If you need a special memory type, then must create a new - * cache for that memory type. - * - * In order to reduce fragmentation, the slabs are sorted in 3 groups: - * full slabs with 0 free objects - * partial slabs - * empty slabs with no allocated objects - * - * If partial slabs exist, then new allocations come from these slabs, - * otherwise from empty slabs or new slabs are allocated. - * - * kmem_cache_destroy() CAN CRASH if you try to allocate from the cache - * during kmem_cache_destroy(). The caller must prevent concurrent allocs. - * - * Each cache has a short per-cpu head array, most allocs - * and frees go into that array, and if that array overflows, then 1/2 - * of the entries in the array are given back into the global cache. - * The head array is strictly LIFO and should improve the cache hit rates. - * On SMP, it additionally reduces the spinlock operations. - * - * The c_cpuarray may not be read with enabled local interrupts - - * it's changed with a smp_call_function(). - * - * SMP synchronization: - * constructors and destructors are called without any locking. - * Several members in struct kmem_cache and struct slab never change, they - * are accessed without any locking. - * The per-cpu arrays are never accessed from the wrong cpu, no locking, - * and local interrupts are disabled so slab code is preempt-safe. - * The non-constant members are protected with a per-cache irq spinlock. - * - * Many thanks to Mark Hemment, who wrote another per-cpu slab patch - * in 2000 - many ideas in the current implementation are derived from - * his patch. - * - * Further notes from the original documentation: - * - * 11 April '97. Started multi-threading - markhe - * The global cache-chain is protected by the mutex 'slab_mutex'. - * The sem is only needed when accessing/extending the cache-chain, which - * can never happen inside an interrupt (kmem_cache_create(), - * kmem_cache_shrink() and kmem_cache_reap()). - * - * At present, each engine can be growing a cache. This should be blocked. - * - * 15 March 2005. NUMA slab allocator. - * Shai Fultheim <shai@scalex86.org>. - * Shobhit Dayal <shobhit@calsoftinc.com> - * Alok N Kataria <alokk@calsoftinc.com> - * Christoph Lameter <christoph@lameter.com> - * - * Modified the slab allocator to be node aware on NUMA systems. - * Each node has its own list of partial, free and full slabs. - * All object allocations for a node occur from node specific slab lists. - */ - -#include <linux/slab.h> -#include <linux/mm.h> -#include <linux/poison.h> -#include <linux/swap.h> -#include <linux/cache.h> -#include <linux/interrupt.h> -#include <linux/init.h> -#include <linux/compiler.h> -#include <linux/cpuset.h> -#include <linux/proc_fs.h> -#include <linux/seq_file.h> -#include <linux/notifier.h> -#include <linux/kallsyms.h> -#include <linux/kfence.h> -#include <linux/cpu.h> -#include <linux/sysctl.h> -#include <linux/module.h> -#include <linux/rcupdate.h> -#include <linux/string.h> -#include <linux/uaccess.h> -#include <linux/nodemask.h> -#include <linux/kmemleak.h> -#include <linux/mempolicy.h> -#include <linux/mutex.h> -#include <linux/fault-inject.h> -#include <linux/rtmutex.h> -#include <linux/reciprocal_div.h> -#include <linux/debugobjects.h> -#include <linux/memory.h> -#include <linux/prefetch.h> -#include <linux/sched/task_stack.h> - -#include <net/sock.h> - -#include <asm/cacheflush.h> -#include <asm/tlbflush.h> -#include <asm/page.h> - -#include <trace/events/kmem.h> - -#include "internal.h" - -#include "slab.h" - -/* - * DEBUG - 1 for kmem_cache_create() to honour; SLAB_RED_ZONE & SLAB_POISON. - * 0 for faster, smaller code (especially in the critical paths). - * - * STATS - 1 to collect stats for /proc/slabinfo. - * 0 for faster, smaller code (especially in the critical paths). - * - * FORCED_DEBUG - 1 enables SLAB_RED_ZONE and SLAB_POISON (if possible) - */ - -#ifdef CONFIG_DEBUG_SLAB -#define DEBUG 1 -#define STATS 1 -#define FORCED_DEBUG 1 -#else -#define DEBUG 0 -#define STATS 0 -#define FORCED_DEBUG 0 -#endif - -/* Shouldn't this be in a header file somewhere? */ -#define BYTES_PER_WORD sizeof(void *) -#define REDZONE_ALIGN max(BYTES_PER_WORD, __alignof__(unsigned long long)) - -#ifndef ARCH_KMALLOC_FLAGS -#define ARCH_KMALLOC_FLAGS SLAB_HWCACHE_ALIGN -#endif - -#define FREELIST_BYTE_INDEX (((PAGE_SIZE >> BITS_PER_BYTE) \ - <= SLAB_OBJ_MIN_SIZE) ? 1 : 0) - -#if FREELIST_BYTE_INDEX -typedef unsigned char freelist_idx_t; -#else -typedef unsigned short freelist_idx_t; -#endif - -#define SLAB_OBJ_MAX_NUM ((1 << sizeof(freelist_idx_t) * BITS_PER_BYTE) - 1) - -/* - * struct array_cache - * - * Purpose: - * - LIFO ordering, to hand out cache-warm objects from _alloc - * - reduce the number of linked list operations - * - reduce spinlock operations - * - * The limit is stored in the per-cpu structure to reduce the data cache - * footprint. - * - */ -struct array_cache { - unsigned int avail; - unsigned int limit; - unsigned int batchcount; - unsigned int touched; - void *entry[]; /* - * Must have this definition in here for the proper - * alignment of array_cache. Also simplifies accessing - * the entries. - */ -}; - -struct alien_cache { - spinlock_t lock; - struct array_cache ac; -}; - -/* - * Need this for bootstrapping a per node allocator. - */ -#define NUM_INIT_LISTS (2 * MAX_NUMNODES) -static struct kmem_cache_node __initdata init_kmem_cache_node[NUM_INIT_LISTS]; -#define CACHE_CACHE 0 -#define SIZE_NODE (MAX_NUMNODES) - -static int drain_freelist(struct kmem_cache *cache, - struct kmem_cache_node *n, int tofree); -static void free_block(struct kmem_cache *cachep, void **objpp, int len, - int node, struct list_head *list); -static void slabs_destroy(struct kmem_cache *cachep, struct list_head *list); -static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp); -static void cache_reap(struct work_struct *unused); - -static inline void fixup_objfreelist_debug(struct kmem_cache *cachep, - void **list); -static inline void fixup_slab_list(struct kmem_cache *cachep, - struct kmem_cache_node *n, struct slab *slab, - void **list); - -#define INDEX_NODE kmalloc_index(sizeof(struct kmem_cache_node)) - -static void kmem_cache_node_init(struct kmem_cache_node *parent) -{ - INIT_LIST_HEAD(&parent->slabs_full); - INIT_LIST_HEAD(&parent->slabs_partial); - INIT_LIST_HEAD(&parent->slabs_free); - parent->total_slabs = 0; - parent->free_slabs = 0; - parent->shared = NULL; - parent->alien = NULL; - parent->colour_next = 0; - raw_spin_lock_init(&parent->list_lock); - parent->free_objects = 0; - parent->free_touched = 0; -} - -#define MAKE_LIST(cachep, listp, slab, nodeid) \ - do { \ - INIT_LIST_HEAD(listp); \ - list_splice(&get_node(cachep, nodeid)->slab, listp); \ - } while (0) - -#define MAKE_ALL_LISTS(cachep, ptr, nodeid) \ - do { \ - MAKE_LIST((cachep), (&(ptr)->slabs_full), slabs_full, nodeid); \ - MAKE_LIST((cachep), (&(ptr)->slabs_partial), slabs_partial, nodeid); \ - MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid); \ - } while (0) - -#define CFLGS_OBJFREELIST_SLAB ((slab_flags_t __force)0x40000000U) -#define CFLGS_OFF_SLAB ((slab_flags_t __force)0x80000000U) -#define OBJFREELIST_SLAB(x) ((x)->flags & CFLGS_OBJFREELIST_SLAB) -#define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB) - -#define BATCHREFILL_LIMIT 16 -/* - * Optimization question: fewer reaps means less probability for unnecessary - * cpucache drain/refill cycles. - * - * OTOH the cpuarrays can contain lots of objects, - * which could lock up otherwise freeable slabs. - */ -#define REAPTIMEOUT_AC (2*HZ) -#define REAPTIMEOUT_NODE (4*HZ) - -#if STATS -#define STATS_INC_ACTIVE(x) ((x)->num_active++) -#define STATS_DEC_ACTIVE(x) ((x)->num_active--) -#define STATS_INC_ALLOCED(x) ((x)->num_allocations++) -#define STATS_INC_GROWN(x) ((x)->grown++) -#define STATS_ADD_REAPED(x, y) ((x)->reaped += (y)) -#define STATS_SET_HIGH(x) \ - do { \ - if ((x)->num_active > (x)->high_mark) \ - (x)->high_mark = (x)->num_active; \ - } while (0) -#define STATS_INC_ERR(x) ((x)->errors++) -#define STATS_INC_NODEALLOCS(x) ((x)->node_allocs++) -#define STATS_INC_NODEFREES(x) ((x)->node_frees++) -#define STATS_INC_ACOVERFLOW(x) ((x)->node_overflow++) -#define STATS_SET_FREEABLE(x, i) \ - do { \ - if ((x)->max_freeable < i) \ - (x)->max_freeable = i; \ - } while (0) -#define STATS_INC_ALLOCHIT(x) atomic_inc(&(x)->allochit) -#define STATS_INC_ALLOCMISS(x) atomic_inc(&(x)->allocmiss) -#define STATS_INC_FREEHIT(x) atomic_inc(&(x)->freehit) -#define STATS_INC_FREEMISS(x) atomic_inc(&(x)->freemiss) -#else -#define STATS_INC_ACTIVE(x) do { } while (0) -#define STATS_DEC_ACTIVE(x) do { } while (0) -#define STATS_INC_ALLOCED(x) do { } while (0) -#define STATS_INC_GROWN(x) do { } while (0) -#define STATS_ADD_REAPED(x, y) do { (void)(y); } while (0) -#define STATS_SET_HIGH(x) do { } while (0) -#define STATS_INC_ERR(x) do { } while (0) -#define STATS_INC_NODEALLOCS(x) do { } while (0) -#define STATS_INC_NODEFREES(x) do { } while (0) -#define STATS_INC_ACOVERFLOW(x) do { } while (0) -#define STATS_SET_FREEABLE(x, i) do { } while (0) -#define STATS_INC_ALLOCHIT(x) do { } while (0) -#define STATS_INC_ALLOCMISS(x) do { } while (0) -#define STATS_INC_FREEHIT(x) do { } while (0) -#define STATS_INC_FREEMISS(x) do { } while (0) -#endif - -#if DEBUG - -/* - * memory layout of objects: - * 0 : objp - * 0 .. cachep->obj_offset - BYTES_PER_WORD - 1: padding. This ensures that - * the end of an object is aligned with the end of the real - * allocation. Catches writes behind the end of the allocation. - * cachep->obj_offset - BYTES_PER_WORD .. cachep->obj_offset - 1: - * redzone word. - * cachep->obj_offset: The real object. - * cachep->size - 2* BYTES_PER_WORD: redzone word [BYTES_PER_WORD long] - * cachep->size - 1* BYTES_PER_WORD: last caller address - * [BYTES_PER_WORD long] - */ -static int obj_offset(struct kmem_cache *cachep) -{ - return cachep->obj_offset; -} - -static unsigned long long *dbg_redzone1(struct kmem_cache *cachep, void *objp) -{ - BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); - return (unsigned long long *) (objp + obj_offset(cachep) - - sizeof(unsigned long long)); -} - -static unsigned long long *dbg_redzone2(struct kmem_cache *cachep, void *objp) -{ - BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); - if (cachep->flags & SLAB_STORE_USER) - return (unsigned long long *)(objp + cachep->size - - sizeof(unsigned long long) - - REDZONE_ALIGN); - return (unsigned long long *) (objp + cachep->size - - sizeof(unsigned long long)); -} - -static void **dbg_userword(struct kmem_cache *cachep, void *objp) -{ - BUG_ON(!(cachep->flags & SLAB_STORE_USER)); - return (void **)(objp + cachep->size - BYTES_PER_WORD); -} - -#else - -#define obj_offset(x) 0 -#define dbg_redzone1(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) -#define dbg_redzone2(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) -#define dbg_userword(cachep, objp) ({BUG(); (void **)NULL;}) - -#endif - -/* - * Do not go above this order unless 0 objects fit into the slab or - * overridden on the command line. - */ -#define SLAB_MAX_ORDER_HI 1 -#define SLAB_MAX_ORDER_LO 0 -static int slab_max_order = SLAB_MAX_ORDER_LO; -static bool slab_max_order_set __initdata; - -static inline void *index_to_obj(struct kmem_cache *cache, - const struct slab *slab, unsigned int idx) -{ - return slab->s_mem + cache->size * idx; -} - -#define BOOT_CPUCACHE_ENTRIES 1 -/* internal cache of cache description objs */ -static struct kmem_cache kmem_cache_boot = { - .batchcount = 1, - .limit = BOOT_CPUCACHE_ENTRIES, - .shared = 1, - .size = sizeof(struct kmem_cache), - .name = "kmem_cache", -}; - -static DEFINE_PER_CPU(struct delayed_work, slab_reap_work); - -static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) -{ - return this_cpu_ptr(cachep->cpu_cache); -} - -/* - * Calculate the number of objects and left-over bytes for a given buffer size. - */ -static unsigned int cache_estimate(unsigned long gfporder, size_t buffer_size, - slab_flags_t flags, size_t *left_over) -{ - unsigned int num; - size_t slab_size = PAGE_SIZE << gfporder; - - /* - * The slab management structure can be either off the slab or - * on it. For the latter case, the memory allocated for a - * slab is used for: - * - * - @buffer_size bytes for each object - * - One freelist_idx_t for each object - * - * We don't need to consider alignment of freelist because - * freelist will be at the end of slab page. The objects will be - * at the correct alignment. - * - * If the slab management structure is off the slab, then the - * alignment will already be calculated into the size. Because - * the slabs are all pages aligned, the objects will be at the - * correct alignment when allocated. - */ - if (flags & (CFLGS_OBJFREELIST_SLAB | CFLGS_OFF_SLAB)) { - num = slab_size / buffer_size; - *left_over = slab_size % buffer_size; - } else { - num = slab_size / (buffer_size + sizeof(freelist_idx_t)); - *left_over = slab_size % - (buffer_size + sizeof(freelist_idx_t)); - } - - return num; -} - -#if DEBUG -#define slab_error(cachep, msg) __slab_error(__func__, cachep, msg) - -static void __slab_error(const char *function, struct kmem_cache *cachep, - char *msg) -{ - pr_err("slab error in %s(): cache `%s': %s\n", - function, cachep->name, msg); - dump_stack(); - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); -} -#endif - -/* - * By default on NUMA we use alien caches to stage the freeing of - * objects allocated from other nodes. This causes massive memory - * inefficiencies when using fake NUMA setup to split memory into a - * large number of small nodes, so it can be disabled on the command - * line - */ - -static int use_alien_caches __read_mostly = 1; -static int __init noaliencache_setup(char *s) -{ - use_alien_caches = 0; - return 1; -} -__setup("noaliencache", noaliencache_setup); - -static int __init slab_max_order_setup(char *str) -{ - get_option(&str, &slab_max_order); - slab_max_order = slab_max_order < 0 ? 0 : - min(slab_max_order, MAX_ORDER - 1); - slab_max_order_set = true; - - return 1; -} -__setup("slab_max_order=", slab_max_order_setup); - -#ifdef CONFIG_NUMA -/* - * Special reaping functions for NUMA systems called from cache_reap(). - * These take care of doing round robin flushing of alien caches (containing - * objects freed on different nodes from which they were allocated) and the - * flushing of remote pcps by calling drain_node_pages. - */ -static DEFINE_PER_CPU(unsigned long, slab_reap_node); - -static void init_reap_node(int cpu) -{ - per_cpu(slab_reap_node, cpu) = next_node_in(cpu_to_mem(cpu), - node_online_map); -} - -static void next_reap_node(void) -{ - int node = __this_cpu_read(slab_reap_node); - - node = next_node_in(node, node_online_map); - __this_cpu_write(slab_reap_node, node); -} - -#else -#define init_reap_node(cpu) do { } while (0) -#define next_reap_node(void) do { } while (0) -#endif - -/* - * Initiate the reap timer running on the target CPU. We run at around 1 to 2Hz - * via the workqueue/eventd. - * Add the CPU number into the expiration time to minimize the possibility of - * the CPUs getting into lockstep and contending for the global cache chain - * lock. - */ -static void start_cpu_timer(int cpu) -{ - struct delayed_work *reap_work = &per_cpu(slab_reap_work, cpu); - - if (reap_work->work.func == NULL) { - init_reap_node(cpu); - INIT_DEFERRABLE_WORK(reap_work, cache_reap); - schedule_delayed_work_on(cpu, reap_work, - __round_jiffies_relative(HZ, cpu)); - } -} - -static void init_arraycache(struct array_cache *ac, int limit, int batch) -{ - if (ac) { - ac->avail = 0; - ac->limit = limit; - ac->batchcount = batch; - ac->touched = 0; - } -} - -static struct array_cache *alloc_arraycache(int node, int entries, - int batchcount, gfp_t gfp) -{ - size_t memsize = sizeof(void *) * entries + sizeof(struct array_cache); - struct array_cache *ac = NULL; - - ac = kmalloc_node(memsize, gfp, node); - /* - * The array_cache structures contain pointers to free object. - * However, when such objects are allocated or transferred to another - * cache the pointers are not cleared and they could be counted as - * valid references during a kmemleak scan. Therefore, kmemleak must - * not scan such objects. - */ - kmemleak_no_scan(ac); - init_arraycache(ac, entries, batchcount); - return ac; -} - -static noinline void cache_free_pfmemalloc(struct kmem_cache *cachep, - struct slab *slab, void *objp) -{ - struct kmem_cache_node *n; - int slab_node; - LIST_HEAD(list); - - slab_node = slab_nid(slab); - n = get_node(cachep, slab_node); - - raw_spin_lock(&n->list_lock); - free_block(cachep, &objp, 1, slab_node, &list); - raw_spin_unlock(&n->list_lock); - - slabs_destroy(cachep, &list); -} - -/* - * Transfer objects in one arraycache to another. - * Locking must be handled by the caller. - * - * Return the number of entries transferred. - */ -static int transfer_objects(struct array_cache *to, - struct array_cache *from, unsigned int max) -{ - /* Figure out how many entries to transfer */ - int nr = min3(from->avail, max, to->limit - to->avail); - - if (!nr) - return 0; - - memcpy(to->entry + to->avail, from->entry + from->avail - nr, - sizeof(void *) *nr); - - from->avail -= nr; - to->avail += nr; - return nr; -} - -/* &alien->lock must be held by alien callers. */ -static __always_inline void __free_one(struct array_cache *ac, void *objp) -{ - /* Avoid trivial double-free. */ - if (IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && - WARN_ON_ONCE(ac->avail > 0 && ac->entry[ac->avail - 1] == objp)) - return; - ac->entry[ac->avail++] = objp; -} - -#ifndef CONFIG_NUMA - -#define drain_alien_cache(cachep, alien) do { } while (0) -#define reap_alien(cachep, n) do { } while (0) - -static inline struct alien_cache **alloc_alien_cache(int node, - int limit, gfp_t gfp) -{ - return NULL; -} - -static inline void free_alien_cache(struct alien_cache **ac_ptr) -{ -} - -static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) -{ - return 0; -} - -static inline gfp_t gfp_exact_node(gfp_t flags) -{ - return flags & ~__GFP_NOFAIL; -} - -#else /* CONFIG_NUMA */ - -static struct alien_cache *__alloc_alien_cache(int node, int entries, - int batch, gfp_t gfp) -{ - size_t memsize = sizeof(void *) * entries + sizeof(struct alien_cache); - struct alien_cache *alc = NULL; - - alc = kmalloc_node(memsize, gfp, node); - if (alc) { - kmemleak_no_scan(alc); - init_arraycache(&alc->ac, entries, batch); - spin_lock_init(&alc->lock); - } - return alc; -} - -static struct alien_cache **alloc_alien_cache(int node, int limit, gfp_t gfp) -{ - struct alien_cache **alc_ptr; - int i; - - if (limit > 1) - limit = 12; - alc_ptr = kcalloc_node(nr_node_ids, sizeof(void *), gfp, node); - if (!alc_ptr) - return NULL; - - for_each_node(i) { - if (i == node || !node_online(i)) - continue; - alc_ptr[i] = __alloc_alien_cache(node, limit, 0xbaadf00d, gfp); - if (!alc_ptr[i]) { - for (i--; i >= 0; i--) - kfree(alc_ptr[i]); - kfree(alc_ptr); - return NULL; - } - } - return alc_ptr; -} - -static void free_alien_cache(struct alien_cache **alc_ptr) -{ - int i; - - if (!alc_ptr) - return; - for_each_node(i) - kfree(alc_ptr[i]); - kfree(alc_ptr); -} - -static void __drain_alien_cache(struct kmem_cache *cachep, - struct array_cache *ac, int node, - struct list_head *list) -{ - struct kmem_cache_node *n = get_node(cachep, node); - - if (ac->avail) { - raw_spin_lock(&n->list_lock); - /* - * Stuff objects into the remote nodes shared array first. - * That way we could avoid the overhead of putting the objects - * into the free lists and getting them back later. - */ - if (n->shared) - transfer_objects(n->shared, ac, ac->limit); - - free_block(cachep, ac->entry, ac->avail, node, list); - ac->avail = 0; - raw_spin_unlock(&n->list_lock); - } -} - -/* - * Called from cache_reap() to regularly drain alien caches round robin. - */ -static void reap_alien(struct kmem_cache *cachep, struct kmem_cache_node *n) -{ - int node = __this_cpu_read(slab_reap_node); - - if (n->alien) { - struct alien_cache *alc = n->alien[node]; - struct array_cache *ac; - - if (alc) { - ac = &alc->ac; - if (ac->avail && spin_trylock_irq(&alc->lock)) { - LIST_HEAD(list); - - __drain_alien_cache(cachep, ac, node, &list); - spin_unlock_irq(&alc->lock); - slabs_destroy(cachep, &list); - } - } - } -} - -static void drain_alien_cache(struct kmem_cache *cachep, - struct alien_cache **alien) -{ - int i = 0; - struct alien_cache *alc; - struct array_cache *ac; - unsigned long flags; - - for_each_online_node(i) { - alc = alien[i]; - if (alc) { - LIST_HEAD(list); - - ac = &alc->ac; - spin_lock_irqsave(&alc->lock, flags); - __drain_alien_cache(cachep, ac, i, &list); - spin_unlock_irqrestore(&alc->lock, flags); - slabs_destroy(cachep, &list); - } - } -} - -static int __cache_free_alien(struct kmem_cache *cachep, void *objp, - int node, int slab_node) -{ - struct kmem_cache_node *n; - struct alien_cache *alien = NULL; - struct array_cache *ac; - LIST_HEAD(list); - - n = get_node(cachep, node); - STATS_INC_NODEFREES(cachep); - if (n->alien && n->alien[slab_node]) { - alien = n->alien[slab_node]; - ac = &alien->ac; - spin_lock(&alien->lock); - if (unlikely(ac->avail == ac->limit)) { - STATS_INC_ACOVERFLOW(cachep); - __drain_alien_cache(cachep, ac, slab_node, &list); - } - __free_one(ac, objp); - spin_unlock(&alien->lock); - slabs_destroy(cachep, &list); - } else { - n = get_node(cachep, slab_node); - raw_spin_lock(&n->list_lock); - free_block(cachep, &objp, 1, slab_node, &list); - raw_spin_unlock(&n->list_lock); - slabs_destroy(cachep, &list); - } - return 1; -} - -static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) -{ - int slab_node = slab_nid(virt_to_slab(objp)); - int node = numa_mem_id(); - /* - * Make sure we are not freeing an object from another node to the array - * cache on this cpu. - */ - if (likely(node == slab_node)) - return 0; - - return __cache_free_alien(cachep, objp, node, slab_node); -} - -/* - * Construct gfp mask to allocate from a specific node but do not reclaim or - * warn about failures. - */ -static inline gfp_t gfp_exact_node(gfp_t flags) -{ - return (flags | __GFP_THISNODE | __GFP_NOWARN) & ~(__GFP_RECLAIM|__GFP_NOFAIL); -} -#endif - -static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp) -{ - struct kmem_cache_node *n; - - /* - * Set up the kmem_cache_node for cpu before we can - * begin anything. Make sure some other cpu on this - * node has not already allocated this - */ - n = get_node(cachep, node); - if (n) { - raw_spin_lock_irq(&n->list_lock); - n->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount + - cachep->num; - raw_spin_unlock_irq(&n->list_lock); - - return 0; - } - - n = kmalloc_node(sizeof(struct kmem_cache_node), gfp, node); - if (!n) - return -ENOMEM; - - kmem_cache_node_init(n); - n->next_reap = jiffies + REAPTIMEOUT_NODE + - ((unsigned long)cachep) % REAPTIMEOUT_NODE; - - n->free_limit = - (1 + nr_cpus_node(node)) * cachep->batchcount + cachep->num; - - /* - * The kmem_cache_nodes don't come and go as CPUs - * come and go. slab_mutex provides sufficient - * protection here. - */ - cachep->node[node] = n; - - return 0; -} - -#if defined(CONFIG_NUMA) || defined(CONFIG_SMP) -/* - * Allocates and initializes node for a node on each slab cache, used for - * either memory or cpu hotplug. If memory is being hot-added, the kmem_cache_node - * will be allocated off-node since memory is not yet online for the new node. - * When hotplugging memory or a cpu, existing nodes are not replaced if - * already in use. - * - * Must hold slab_mutex. - */ -static int init_cache_node_node(int node) -{ - int ret; - struct kmem_cache *cachep; - - list_for_each_entry(cachep, &slab_caches, list) { - ret = init_cache_node(cachep, node, GFP_KERNEL); - if (ret) - return ret; - } - - return 0; -} -#endif - -static int setup_kmem_cache_node(struct kmem_cache *cachep, - int node, gfp_t gfp, bool force_change) -{ - int ret = -ENOMEM; - struct kmem_cache_node *n; - struct array_cache *old_shared = NULL; - struct array_cache *new_shared = NULL; - struct alien_cache **new_alien = NULL; - LIST_HEAD(list); - - if (use_alien_caches) { - new_alien = alloc_alien_cache(node, cachep->limit, gfp); - if (!new_alien) - goto fail; - } - - if (cachep->shared) { - new_shared = alloc_arraycache(node, - cachep->shared * cachep->batchcount, 0xbaadf00d, gfp); - if (!new_shared) - goto fail; - } - - ret = init_cache_node(cachep, node, gfp); - if (ret) - goto fail; - - n = get_node(cachep, node); - raw_spin_lock_irq(&n->list_lock); - if (n->shared && force_change) { - free_block(cachep, n->shared->entry, - n->shared->avail, node, &list); - n->shared->avail = 0; - } - - if (!n->shared || force_change) { - old_shared = n->shared; - n->shared = new_shared; - new_shared = NULL; - } - - if (!n->alien) { - n->alien = new_alien; - new_alien = NULL; - } - - raw_spin_unlock_irq(&n->list_lock); - slabs_destroy(cachep, &list); - - /* - * To protect lockless access to n->shared during irq disabled context. - * If n->shared isn't NULL in irq disabled context, accessing to it is - * guaranteed to be valid until irq is re-enabled, because it will be - * freed after synchronize_rcu(). - */ - if (old_shared && force_change) - synchronize_rcu(); - -fail: - kfree(old_shared); - kfree(new_shared); - free_alien_cache(new_alien); - - return ret; -} - -#ifdef CONFIG_SMP - -static void cpuup_canceled(long cpu) -{ - struct kmem_cache *cachep; - struct kmem_cache_node *n = NULL; - int node = cpu_to_mem(cpu); - const struct cpumask *mask = cpumask_of_node(node); - - list_for_each_entry(cachep, &slab_caches, list) { - struct array_cache *nc; - struct array_cache *shared; - struct alien_cache **alien; - LIST_HEAD(list); - - n = get_node(cachep, node); - if (!n) - continue; - - raw_spin_lock_irq(&n->list_lock); - - /* Free limit for this kmem_cache_node */ - n->free_limit -= cachep->batchcount; - - /* cpu is dead; no one can alloc from it. */ - nc = per_cpu_ptr(cachep->cpu_cache, cpu); - free_block(cachep, nc->entry, nc->avail, node, &list); - nc->avail = 0; - - if (!cpumask_empty(mask)) { - raw_spin_unlock_irq(&n->list_lock); - goto free_slab; - } - - shared = n->shared; - if (shared) { - free_block(cachep, shared->entry, - shared->avail, node, &list); - n->shared = NULL; - } - - alien = n->alien; - n->alien = NULL; - - raw_spin_unlock_irq(&n->list_lock); - - kfree(shared); - if (alien) { - drain_alien_cache(cachep, alien); - free_alien_cache(alien); - } - -free_slab: - slabs_destroy(cachep, &list); - } - /* - * In the previous loop, all the objects were freed to - * the respective cache's slabs, now we can go ahead and - * shrink each nodelist to its limit. - */ - list_for_each_entry(cachep, &slab_caches, list) { - n = get_node(cachep, node); - if (!n) - continue; - drain_freelist(cachep, n, INT_MAX); - } -} - -static int cpuup_prepare(long cpu) -{ - struct kmem_cache *cachep; - int node = cpu_to_mem(cpu); - int err; - - /* - * We need to do this right in the beginning since - * alloc_arraycache's are going to use this list. - * kmalloc_node allows us to add the slab to the right - * kmem_cache_node and not this cpu's kmem_cache_node - */ - err = init_cache_node_node(node); - if (err < 0) - goto bad; - - /* - * Now we can go ahead with allocating the shared arrays and - * array caches - */ - list_for_each_entry(cachep, &slab_caches, list) { - err = setup_kmem_cache_node(cachep, node, GFP_KERNEL, false); - if (err) - goto bad; - } - - return 0; -bad: - cpuup_canceled(cpu); - return -ENOMEM; -} - -int slab_prepare_cpu(unsigned int cpu) -{ - int err; - - mutex_lock(&slab_mutex); - err = cpuup_prepare(cpu); - mutex_unlock(&slab_mutex); - return err; -} - -/* - * This is called for a failed online attempt and for a successful - * offline. - * - * Even if all the cpus of a node are down, we don't free the - * kmem_cache_node of any cache. This is to avoid a race between cpu_down, and - * a kmalloc allocation from another cpu for memory from the node of - * the cpu going down. The kmem_cache_node structure is usually allocated from - * kmem_cache_create() and gets destroyed at kmem_cache_destroy(). - */ -int slab_dead_cpu(unsigned int cpu) -{ - mutex_lock(&slab_mutex); - cpuup_canceled(cpu); - mutex_unlock(&slab_mutex); - return 0; -} -#endif - -static int slab_online_cpu(unsigned int cpu) -{ - start_cpu_timer(cpu); - return 0; -} - -static int slab_offline_cpu(unsigned int cpu) -{ - /* - * Shutdown cache reaper. Note that the slab_mutex is held so - * that if cache_reap() is invoked it cannot do anything - * expensive but will only modify reap_work and reschedule the - * timer. - */ - cancel_delayed_work_sync(&per_cpu(slab_reap_work, cpu)); - /* Now the cache_reaper is guaranteed to be not running. */ - per_cpu(slab_reap_work, cpu).work.func = NULL; - return 0; -} - -#if defined(CONFIG_NUMA) -/* - * Drains freelist for a node on each slab cache, used for memory hot-remove. - * Returns -EBUSY if all objects cannot be drained so that the node is not - * removed. - * - * Must hold slab_mutex. - */ -static int __meminit drain_cache_node_node(int node) -{ - struct kmem_cache *cachep; - int ret = 0; - - list_for_each_entry(cachep, &slab_caches, list) { - struct kmem_cache_node *n; - - n = get_node(cachep, node); - if (!n) - continue; - - drain_freelist(cachep, n, INT_MAX); - - if (!list_empty(&n->slabs_full) || - !list_empty(&n->slabs_partial)) { - ret = -EBUSY; - break; - } - } - return ret; -} - -static int __meminit slab_memory_callback(struct notifier_block *self, - unsigned long action, void *arg) -{ - struct memory_notify *mnb = arg; - int ret = 0; - int nid; - - nid = mnb->status_change_nid; - if (nid < 0) - goto out; - - switch (action) { - case MEM_GOING_ONLINE: - mutex_lock(&slab_mutex); - ret = init_cache_node_node(nid); - mutex_unlock(&slab_mutex); - break; - case MEM_GOING_OFFLINE: - mutex_lock(&slab_mutex); - ret = drain_cache_node_node(nid); - mutex_unlock(&slab_mutex); - break; - case MEM_ONLINE: - case MEM_OFFLINE: - case MEM_CANCEL_ONLINE: - case MEM_CANCEL_OFFLINE: - break; - } -out: - return notifier_from_errno(ret); -} -#endif /* CONFIG_NUMA */ - -/* - * swap the static kmem_cache_node with kmalloced memory - */ -static void __init init_list(struct kmem_cache *cachep, struct kmem_cache_node *list, - int nodeid) -{ - struct kmem_cache_node *ptr; - - ptr = kmalloc_node(sizeof(struct kmem_cache_node), GFP_NOWAIT, nodeid); - BUG_ON(!ptr); - - memcpy(ptr, list, sizeof(struct kmem_cache_node)); - /* - * Do not assume that spinlocks can be initialized via memcpy: - */ - raw_spin_lock_init(&ptr->list_lock); - - MAKE_ALL_LISTS(cachep, ptr, nodeid); - cachep->node[nodeid] = ptr; -} - -/* - * For setting up all the kmem_cache_node for cache whose buffer_size is same as - * size of kmem_cache_node. - */ -static void __init set_up_node(struct kmem_cache *cachep, int index) -{ - int node; - - for_each_online_node(node) { - cachep->node[node] = &init_kmem_cache_node[index + node]; - cachep->node[node]->next_reap = jiffies + - REAPTIMEOUT_NODE + - ((unsigned long)cachep) % REAPTIMEOUT_NODE; - } -} - -/* - * Initialisation. Called after the page allocator have been initialised and - * before smp_init(). - */ -void __init kmem_cache_init(void) -{ - int i; - - kmem_cache = &kmem_cache_boot; - - if (!IS_ENABLED(CONFIG_NUMA) || num_possible_nodes() == 1) - use_alien_caches = 0; - - for (i = 0; i < NUM_INIT_LISTS; i++) - kmem_cache_node_init(&init_kmem_cache_node[i]); - - /* - * Fragmentation resistance on low memory - only use bigger - * page orders on machines with more than 32MB of memory if - * not overridden on the command line. - */ - if (!slab_max_order_set && totalram_pages() > (32 << 20) >> PAGE_SHIFT) - slab_max_order = SLAB_MAX_ORDER_HI; - - /* Bootstrap is tricky, because several objects are allocated - * from caches that do not exist yet: - * 1) initialize the kmem_cache cache: it contains the struct - * kmem_cache structures of all caches, except kmem_cache itself: - * kmem_cache is statically allocated. - * Initially an __init data area is used for the head array and the - * kmem_cache_node structures, it's replaced with a kmalloc allocated - * array at the end of the bootstrap. - * 2) Create the first kmalloc cache. - * The struct kmem_cache for the new cache is allocated normally. - * An __init data area is used for the head array. - * 3) Create the remaining kmalloc caches, with minimally sized - * head arrays. - * 4) Replace the __init data head arrays for kmem_cache and the first - * kmalloc cache with kmalloc allocated arrays. - * 5) Replace the __init data for kmem_cache_node for kmem_cache and - * the other cache's with kmalloc allocated memory. - * 6) Resize the head arrays of the kmalloc caches to their final sizes. - */ - - /* 1) create the kmem_cache */ - - /* - * struct kmem_cache size depends on nr_node_ids & nr_cpu_ids - */ - create_boot_cache(kmem_cache, "kmem_cache", - offsetof(struct kmem_cache, node) + - nr_node_ids * sizeof(struct kmem_cache_node *), - SLAB_HWCACHE_ALIGN, 0, 0); - list_add(&kmem_cache->list, &slab_caches); - slab_state = PARTIAL; - - /* - * Initialize the caches that provide memory for the kmem_cache_node - * structures first. Without this, further allocations will bug. - */ - kmalloc_caches[KMALLOC_NORMAL][INDEX_NODE] = create_kmalloc_cache( - kmalloc_info[INDEX_NODE].name[KMALLOC_NORMAL], - kmalloc_info[INDEX_NODE].size, - ARCH_KMALLOC_FLAGS, 0, - kmalloc_info[INDEX_NODE].size); - slab_state = PARTIAL_NODE; - setup_kmalloc_cache_index_table(); - - /* 5) Replace the bootstrap kmem_cache_node */ - { - int nid; - - for_each_online_node(nid) { - init_list(kmem_cache, &init_kmem_cache_node[CACHE_CACHE + nid], nid); - - init_list(kmalloc_caches[KMALLOC_NORMAL][INDEX_NODE], - &init_kmem_cache_node[SIZE_NODE + nid], nid); - } - } - - create_kmalloc_caches(ARCH_KMALLOC_FLAGS); -} - -void __init kmem_cache_init_late(void) -{ - struct kmem_cache *cachep; - - /* 6) resize the head arrays to their final sizes */ - mutex_lock(&slab_mutex); - list_for_each_entry(cachep, &slab_caches, list) - if (enable_cpucache(cachep, GFP_NOWAIT)) - BUG(); - mutex_unlock(&slab_mutex); - - /* Done! */ - slab_state = FULL; - -#ifdef CONFIG_NUMA - /* - * Register a memory hotplug callback that initializes and frees - * node. - */ - hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI); -#endif - - /* - * The reap timers are started later, with a module init call: That part - * of the kernel is not yet operational. - */ -} - -static int __init cpucache_init(void) -{ - int ret; - - /* - * Register the timers that return unneeded pages to the page allocator - */ - ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "SLAB online", - slab_online_cpu, slab_offline_cpu); - WARN_ON(ret < 0); - - return 0; -} -__initcall(cpucache_init); - -static noinline void -slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid) -{ -#if DEBUG - struct kmem_cache_node *n; - unsigned long flags; - int node; - static DEFINE_RATELIMIT_STATE(slab_oom_rs, DEFAULT_RATELIMIT_INTERVAL, - DEFAULT_RATELIMIT_BURST); - - if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slab_oom_rs)) - return; - - pr_warn("SLAB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", - nodeid, gfpflags, &gfpflags); - pr_warn(" cache: %s, object size: %d, order: %d\n", - cachep->name, cachep->size, cachep->gfporder); - - for_each_kmem_cache_node(cachep, node, n) { - unsigned long total_slabs, free_slabs, free_objs; - - raw_spin_lock_irqsave(&n->list_lock, flags); - total_slabs = n->total_slabs; - free_slabs = n->free_slabs; - free_objs = n->free_objects; - raw_spin_unlock_irqrestore(&n->list_lock, flags); - - pr_warn(" node %d: slabs: %ld/%ld, objs: %ld/%ld\n", - node, total_slabs - free_slabs, total_slabs, - (total_slabs * cachep->num) - free_objs, - total_slabs * cachep->num); - } -#endif -} - -/* - * Interface to system's page allocator. No need to hold the - * kmem_cache_node ->list_lock. - * - * If we requested dmaable memory, we will get it. Even if we - * did not request dmaable memory, we might get it, but that - * would be relatively rare and ignorable. - */ -static struct slab *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, - int nodeid) -{ - struct folio *folio; - struct slab *slab; - - flags |= cachep->allocflags; - - folio = (struct folio *) __alloc_pages_node(nodeid, flags, cachep->gfporder); - if (!folio) { - slab_out_of_memory(cachep, flags, nodeid); - return NULL; - } - - slab = folio_slab(folio); - - account_slab(slab, cachep->gfporder, cachep, flags); - __folio_set_slab(folio); - /* Make the flag visible before any changes to folio->mapping */ - smp_wmb(); - /* Record if ALLOC_NO_WATERMARKS was set when allocating the slab */ - if (sk_memalloc_socks() && folio_is_pfmemalloc(folio)) - slab_set_pfmemalloc(slab); - - return slab; -} - -/* - * Interface to system's page release. - */ -static void kmem_freepages(struct kmem_cache *cachep, struct slab *slab) -{ - int order = cachep->gfporder; - struct folio *folio = slab_folio(slab); - - BUG_ON(!folio_test_slab(folio)); - __slab_clear_pfmemalloc(slab); - page_mapcount_reset(&folio->page); - folio->mapping = NULL; - /* Make the mapping reset visible before clearing the flag */ - smp_wmb(); - __folio_clear_slab(folio); - - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += 1 << order; - unaccount_slab(slab, order, cachep); - __free_pages(&folio->page, order); -} - -static void kmem_rcu_free(struct rcu_head *head) -{ - struct kmem_cache *cachep; - struct slab *slab; - - slab = container_of(head, struct slab, rcu_head); - cachep = slab->slab_cache; - - kmem_freepages(cachep, slab); -} - -#if DEBUG -static inline bool is_debug_pagealloc_cache(struct kmem_cache *cachep) -{ - return debug_pagealloc_enabled_static() && OFF_SLAB(cachep) && - ((cachep->size % PAGE_SIZE) == 0); -} - -#ifdef CONFIG_DEBUG_PAGEALLOC -static void slab_kernel_map(struct kmem_cache *cachep, void *objp, int map) -{ - if (!is_debug_pagealloc_cache(cachep)) - return; - - __kernel_map_pages(virt_to_page(objp), cachep->size / PAGE_SIZE, map); -} - -#else -static inline void slab_kernel_map(struct kmem_cache *cachep, void *objp, - int map) {} - -#endif - -static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val) -{ - int size = cachep->object_size; - addr = &((char *)addr)[obj_offset(cachep)]; - - memset(addr, val, size); - *(unsigned char *)(addr + size - 1) = POISON_END; -} - -static void dump_line(char *data, int offset, int limit) -{ - int i; - unsigned char error = 0; - int bad_count = 0; - - pr_err("%03x: ", offset); - for (i = 0; i < limit; i++) { - if (data[offset + i] != POISON_FREE) { - error = data[offset + i]; - bad_count++; - } - } - print_hex_dump(KERN_CONT, "", 0, 16, 1, - &data[offset], limit, 1); - - if (bad_count == 1) { - error ^= POISON_FREE; - if (!(error & (error - 1))) { - pr_err("Single bit error detected. Probably bad RAM.\n"); -#ifdef CONFIG_X86 - pr_err("Run memtest86+ or a similar memory test tool.\n"); -#else - pr_err("Run a memory test tool.\n"); -#endif - } - } -} -#endif - -#if DEBUG - -static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines) -{ - int i, size; - char *realobj; - - if (cachep->flags & SLAB_RED_ZONE) { - pr_err("Redzone: 0x%llx/0x%llx\n", - *dbg_redzone1(cachep, objp), - *dbg_redzone2(cachep, objp)); - } - - if (cachep->flags & SLAB_STORE_USER) - pr_err("Last user: (%pSR)\n", *dbg_userword(cachep, objp)); - realobj = (char *)objp + obj_offset(cachep); - size = cachep->object_size; - for (i = 0; i < size && lines; i += 16, lines--) { - int limit; - limit = 16; - if (i + limit > size) - limit = size - i; - dump_line(realobj, i, limit); - } -} - -static void check_poison_obj(struct kmem_cache *cachep, void *objp) -{ - char *realobj; - int size, i; - int lines = 0; - - if (is_debug_pagealloc_cache(cachep)) - return; - - realobj = (char *)objp + obj_offset(cachep); - size = cachep->object_size; - - for (i = 0; i < size; i++) { - char exp = POISON_FREE; - if (i == size - 1) - exp = POISON_END; - if (realobj[i] != exp) { - int limit; - /* Mismatch ! */ - /* Print header */ - if (lines == 0) { - pr_err("Slab corruption (%s): %s start=%px, len=%d\n", - print_tainted(), cachep->name, - realobj, size); - print_objinfo(cachep, objp, 0); - } - /* Hexdump the affected line */ - i = (i / 16) * 16; - limit = 16; - if (i + limit > size) - limit = size - i; - dump_line(realobj, i, limit); - i += 16; - lines++; - /* Limit to 5 lines */ - if (lines > 5) - break; - } - } - if (lines != 0) { - /* Print some data about the neighboring objects, if they - * exist: - */ - struct slab *slab = virt_to_slab(objp); - unsigned int objnr; - - objnr = obj_to_index(cachep, slab, objp); - if (objnr) { - objp = index_to_obj(cachep, slab, objnr - 1); - realobj = (char *)objp + obj_offset(cachep); - pr_err("Prev obj: start=%px, len=%d\n", realobj, size); - print_objinfo(cachep, objp, 2); - } - if (objnr + 1 < cachep->num) { - objp = index_to_obj(cachep, slab, objnr + 1); - realobj = (char *)objp + obj_offset(cachep); - pr_err("Next obj: start=%px, len=%d\n", realobj, size); - print_objinfo(cachep, objp, 2); - } - } -} -#endif - -#if DEBUG -static void slab_destroy_debugcheck(struct kmem_cache *cachep, - struct slab *slab) -{ - int i; - - if (OBJFREELIST_SLAB(cachep) && cachep->flags & SLAB_POISON) { - poison_obj(cachep, slab->freelist - obj_offset(cachep), - POISON_FREE); - } - - for (i = 0; i < cachep->num; i++) { - void *objp = index_to_obj(cachep, slab, i); - - if (cachep->flags & SLAB_POISON) { - check_poison_obj(cachep, objp); - slab_kernel_map(cachep, objp, 1); - } - if (cachep->flags & SLAB_RED_ZONE) { - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) - slab_error(cachep, "start of a freed object was overwritten"); - if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) - slab_error(cachep, "end of a freed object was overwritten"); - } - } -} -#else -static void slab_destroy_debugcheck(struct kmem_cache *cachep, - struct slab *slab) -{ -} -#endif - -/** - * slab_destroy - destroy and release all objects in a slab - * @cachep: cache pointer being destroyed - * @slab: slab being destroyed - * - * Destroy all the objs in a slab, and release the mem back to the system. - * Before calling the slab must have been unlinked from the cache. The - * kmem_cache_node ->list_lock is not held/needed. - */ -static void slab_destroy(struct kmem_cache *cachep, struct slab *slab) -{ - void *freelist; - - freelist = slab->freelist; - slab_destroy_debugcheck(cachep, slab); - if (unlikely(cachep->flags & SLAB_TYPESAFE_BY_RCU)) - call_rcu(&slab->rcu_head, kmem_rcu_free); - else - kmem_freepages(cachep, slab); - - /* - * From now on, we don't use freelist - * although actual page can be freed in rcu context - */ - if (OFF_SLAB(cachep)) - kfree(freelist); -} - -/* - * Update the size of the caches before calling slabs_destroy as it may - * recursively call kfree. - */ -static void slabs_destroy(struct kmem_cache *cachep, struct list_head *list) -{ - struct slab *slab, *n; - - list_for_each_entry_safe(slab, n, list, slab_list) { - list_del(&slab->slab_list); - slab_destroy(cachep, slab); - } -} - -/** - * calculate_slab_order - calculate size (page order) of slabs - * @cachep: pointer to the cache that is being created - * @size: size of objects to be created in this cache. - * @flags: slab allocation flags - * - * Also calculates the number of objects per slab. - * - * This could be made much more intelligent. For now, try to avoid using - * high order pages for slabs. When the gfp() functions are more friendly - * towards high-order requests, this should be changed. - * - * Return: number of left-over bytes in a slab - */ -static size_t calculate_slab_order(struct kmem_cache *cachep, - size_t size, slab_flags_t flags) -{ - size_t left_over = 0; - int gfporder; - - for (gfporder = 0; gfporder <= KMALLOC_MAX_ORDER; gfporder++) { - unsigned int num; - size_t remainder; - - num = cache_estimate(gfporder, size, flags, &remainder); - if (!num) - continue; - - /* Can't handle number of objects more than SLAB_OBJ_MAX_NUM */ - if (num > SLAB_OBJ_MAX_NUM) - break; - - if (flags & CFLGS_OFF_SLAB) { - struct kmem_cache *freelist_cache; - size_t freelist_size; - size_t freelist_cache_size; - - freelist_size = num * sizeof(freelist_idx_t); - if (freelist_size > KMALLOC_MAX_CACHE_SIZE) { - freelist_cache_size = PAGE_SIZE << get_order(freelist_size); - } else { - freelist_cache = kmalloc_slab(freelist_size, 0u); - if (!freelist_cache) - continue; - freelist_cache_size = freelist_cache->size; - - /* - * Needed to avoid possible looping condition - * in cache_grow_begin() - */ - if (OFF_SLAB(freelist_cache)) - continue; - } - - /* check if off slab has enough benefit */ - if (freelist_cache_size > cachep->size / 2) - continue; - } - - /* Found something acceptable - save it away */ - cachep->num = num; - cachep->gfporder = gfporder; - left_over = remainder; - - /* - * A VFS-reclaimable slab tends to have most allocations - * as GFP_NOFS and we really don't want to have to be allocating - * higher-order pages when we are unable to shrink dcache. - */ - if (flags & SLAB_RECLAIM_ACCOUNT) - break; - - /* - * Large number of objects is good, but very large slabs are - * currently bad for the gfp()s. - */ - if (gfporder >= slab_max_order) - break; - - /* - * Acceptable internal fragmentation? - */ - if (left_over * 8 <= (PAGE_SIZE << gfporder)) - break; - } - return left_over; -} - -static struct array_cache __percpu *alloc_kmem_cache_cpus( - struct kmem_cache *cachep, int entries, int batchcount) -{ - int cpu; - size_t size; - struct array_cache __percpu *cpu_cache; - - size = sizeof(void *) * entries + sizeof(struct array_cache); - cpu_cache = __alloc_percpu(size, sizeof(void *)); - - if (!cpu_cache) - return NULL; - - for_each_possible_cpu(cpu) { - init_arraycache(per_cpu_ptr(cpu_cache, cpu), - entries, batchcount); - } - - return cpu_cache; -} - -static int __ref setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp) -{ - if (slab_state >= FULL) - return enable_cpucache(cachep, gfp); - - cachep->cpu_cache = alloc_kmem_cache_cpus(cachep, 1, 1); - if (!cachep->cpu_cache) - return 1; - - if (slab_state == DOWN) { - /* Creation of first cache (kmem_cache). */ - set_up_node(kmem_cache, CACHE_CACHE); - } else if (slab_state == PARTIAL) { - /* For kmem_cache_node */ - set_up_node(cachep, SIZE_NODE); - } else { - int node; - - for_each_online_node(node) { - cachep->node[node] = kmalloc_node( - sizeof(struct kmem_cache_node), gfp, node); - BUG_ON(!cachep->node[node]); - kmem_cache_node_init(cachep->node[node]); - } - } - - cachep->node[numa_mem_id()]->next_reap = - jiffies + REAPTIMEOUT_NODE + - ((unsigned long)cachep) % REAPTIMEOUT_NODE; - - cpu_cache_get(cachep)->avail = 0; - cpu_cache_get(cachep)->limit = BOOT_CPUCACHE_ENTRIES; - cpu_cache_get(cachep)->batchcount = 1; - cpu_cache_get(cachep)->touched = 0; - cachep->batchcount = 1; - cachep->limit = BOOT_CPUCACHE_ENTRIES; - return 0; -} - -slab_flags_t kmem_cache_flags(unsigned int object_size, - slab_flags_t flags, const char *name) -{ - return flags; -} - -struct kmem_cache * -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, - slab_flags_t flags, void (*ctor)(void *)) -{ - struct kmem_cache *cachep; - - cachep = find_mergeable(size, align, flags, name, ctor); - if (cachep) { - cachep->refcount++; - - /* - * Adjust the object sizes so that we clear - * the complete object on kzalloc. - */ - cachep->object_size = max_t(int, cachep->object_size, size); - } - return cachep; -} - -static bool set_objfreelist_slab_cache(struct kmem_cache *cachep, - size_t size, slab_flags_t flags) -{ - size_t left; - - cachep->num = 0; - - /* - * If slab auto-initialization on free is enabled, store the freelist - * off-slab, so that its contents don't end up in one of the allocated - * objects. - */ - if (unlikely(slab_want_init_on_free(cachep))) - return false; - - if (cachep->ctor || flags & SLAB_TYPESAFE_BY_RCU) - return false; - - left = calculate_slab_order(cachep, size, - flags | CFLGS_OBJFREELIST_SLAB); - if (!cachep->num) - return false; - - if (cachep->num * sizeof(freelist_idx_t) > cachep->object_size) - return false; - - cachep->colour = left / cachep->colour_off; - - return true; -} - -static bool set_off_slab_cache(struct kmem_cache *cachep, - size_t size, slab_flags_t flags) -{ - size_t left; - - cachep->num = 0; - - /* - * Always use on-slab management when SLAB_NOLEAKTRACE - * to avoid recursive calls into kmemleak. - */ - if (flags & SLAB_NOLEAKTRACE) - return false; - - /* - * Size is large, assume best to place the slab management obj - * off-slab (should allow better packing of objs). - */ - left = calculate_slab_order(cachep, size, flags | CFLGS_OFF_SLAB); - if (!cachep->num) - return false; - - /* - * If the slab has been placed off-slab, and we have enough space then - * move it on-slab. This is at the expense of any extra colouring. - */ - if (left >= cachep->num * sizeof(freelist_idx_t)) - return false; - - cachep->colour = left / cachep->colour_off; - - return true; -} - -static bool set_on_slab_cache(struct kmem_cache *cachep, - size_t size, slab_flags_t flags) -{ - size_t left; - - cachep->num = 0; - - left = calculate_slab_order(cachep, size, flags); - if (!cachep->num) - return false; - - cachep->colour = left / cachep->colour_off; - - return true; -} - -/** - * __kmem_cache_create - Create a cache. - * @cachep: cache management descriptor - * @flags: SLAB flags - * - * Returns a ptr to the cache on success, NULL on failure. - * Cannot be called within an int, but can be interrupted. - * The @ctor is run when new pages are allocated by the cache. - * - * The flags are - * - * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5) - * to catch references to uninitialised memory. - * - * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check - * for buffer overruns. - * - * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware - * cacheline. This can be beneficial if you're counting cycles as closely - * as davem. - * - * Return: a pointer to the created cache or %NULL in case of error - */ -int __kmem_cache_create(struct kmem_cache *cachep, slab_flags_t flags) -{ - size_t ralign = BYTES_PER_WORD; - gfp_t gfp; - int err; - unsigned int size = cachep->size; - -#if DEBUG -#if FORCED_DEBUG - /* - * Enable redzoning and last user accounting, except for caches with - * large objects, if the increased size would increase the object size - * above the next power of two: caches with object sizes just above a - * power of two have a significant amount of internal fragmentation. - */ - if (size < 4096 || fls(size - 1) == fls(size-1 + REDZONE_ALIGN + - 2 * sizeof(unsigned long long))) - flags |= SLAB_RED_ZONE | SLAB_STORE_USER; - if (!(flags & SLAB_TYPESAFE_BY_RCU)) - flags |= SLAB_POISON; -#endif -#endif - - /* - * Check that size is in terms of words. This is needed to avoid - * unaligned accesses for some archs when redzoning is used, and makes - * sure any on-slab bufctl's are also correctly aligned. - */ - size = ALIGN(size, BYTES_PER_WORD); - - if (flags & SLAB_RED_ZONE) { - ralign = REDZONE_ALIGN; - /* If redzoning, ensure that the second redzone is suitably - * aligned, by adjusting the object size accordingly. */ - size = ALIGN(size, REDZONE_ALIGN); - } - - /* 3) caller mandated alignment */ - if (ralign < cachep->align) { - ralign = cachep->align; - } - /* disable debug if necessary */ - if (ralign > __alignof__(unsigned long long)) - flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); - /* - * 4) Store it. - */ - cachep->align = ralign; - cachep->colour_off = cache_line_size(); - /* Offset must be a multiple of the alignment. */ - if (cachep->colour_off < cachep->align) - cachep->colour_off = cachep->align; - - if (slab_is_available()) - gfp = GFP_KERNEL; - else - gfp = GFP_NOWAIT; - -#if DEBUG - - /* - * Both debugging options require word-alignment which is calculated - * into align above. - */ - if (flags & SLAB_RED_ZONE) { - /* add space for red zone words */ - cachep->obj_offset += sizeof(unsigned long long); - size += 2 * sizeof(unsigned long long); - } - if (flags & SLAB_STORE_USER) { - /* user store requires one word storage behind the end of - * the real object. But if the second red zone needs to be - * aligned to 64 bits, we must allow that much space. - */ - if (flags & SLAB_RED_ZONE) - size += REDZONE_ALIGN; - else - size += BYTES_PER_WORD; - } -#endif - - kasan_cache_create(cachep, &size, &flags); - - size = ALIGN(size, cachep->align); - /* - * We should restrict the number of objects in a slab to implement - * byte sized index. Refer comment on SLAB_OBJ_MIN_SIZE definition. - */ - if (FREELIST_BYTE_INDEX && size < SLAB_OBJ_MIN_SIZE) - size = ALIGN(SLAB_OBJ_MIN_SIZE, cachep->align); - -#if DEBUG - /* - * To activate debug pagealloc, off-slab management is necessary - * requirement. In early phase of initialization, small sized slab - * doesn't get initialized so it would not be possible. So, we need - * to check size >= 256. It guarantees that all necessary small - * sized slab is initialized in current slab initialization sequence. - */ - if (debug_pagealloc_enabled_static() && (flags & SLAB_POISON) && - size >= 256 && cachep->object_size > cache_line_size()) { - if (size < PAGE_SIZE || size % PAGE_SIZE == 0) { - size_t tmp_size = ALIGN(size, PAGE_SIZE); - - if (set_off_slab_cache(cachep, tmp_size, flags)) { - flags |= CFLGS_OFF_SLAB; - cachep->obj_offset += tmp_size - size; - size = tmp_size; - goto done; - } - } - } -#endif - - if (set_objfreelist_slab_cache(cachep, size, flags)) { - flags |= CFLGS_OBJFREELIST_SLAB; - goto done; - } - - if (set_off_slab_cache(cachep, size, flags)) { - flags |= CFLGS_OFF_SLAB; - goto done; - } - - if (set_on_slab_cache(cachep, size, flags)) - goto done; - - return -E2BIG; - -done: - cachep->freelist_size = cachep->num * sizeof(freelist_idx_t); - cachep->flags = flags; - cachep->allocflags = __GFP_COMP; - if (flags & SLAB_CACHE_DMA) - cachep->allocflags |= GFP_DMA; - if (flags & SLAB_CACHE_DMA32) - cachep->allocflags |= GFP_DMA32; - if (flags & SLAB_RECLAIM_ACCOUNT) - cachep->allocflags |= __GFP_RECLAIMABLE; - cachep->size = size; - cachep->reciprocal_buffer_size = reciprocal_value(size); - -#if DEBUG - /* - * If we're going to use the generic kernel_map_pages() - * poisoning, then it's going to smash the contents of - * the redzone and userword anyhow, so switch them off. - */ - if (IS_ENABLED(CONFIG_PAGE_POISONING) && - (cachep->flags & SLAB_POISON) && - is_debug_pagealloc_cache(cachep)) - cachep->flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); -#endif - - err = setup_cpu_cache(cachep, gfp); - if (err) { - __kmem_cache_release(cachep); - return err; - } - - return 0; -} - -#if DEBUG -static void check_irq_off(void) -{ - BUG_ON(!irqs_disabled()); -} - -static void check_irq_on(void) -{ - BUG_ON(irqs_disabled()); -} - -static void check_mutex_acquired(void) -{ - BUG_ON(!mutex_is_locked(&slab_mutex)); -} - -static void check_spinlock_acquired(struct kmem_cache *cachep) -{ -#ifdef CONFIG_SMP - check_irq_off(); - assert_raw_spin_locked(&get_node(cachep, numa_mem_id())->list_lock); -#endif -} - -static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node) -{ -#ifdef CONFIG_SMP - check_irq_off(); - assert_raw_spin_locked(&get_node(cachep, node)->list_lock); -#endif -} - -#else -#define check_irq_off() do { } while(0) -#define check_irq_on() do { } while(0) -#define check_mutex_acquired() do { } while(0) -#define check_spinlock_acquired(x) do { } while(0) -#define check_spinlock_acquired_node(x, y) do { } while(0) -#endif - -static void drain_array_locked(struct kmem_cache *cachep, struct array_cache *ac, - int node, bool free_all, struct list_head *list) -{ - int tofree; - - if (!ac || !ac->avail) - return; - - tofree = free_all ? ac->avail : (ac->limit + 4) / 5; - if (tofree > ac->avail) - tofree = (ac->avail + 1) / 2; - - free_block(cachep, ac->entry, tofree, node, list); - ac->avail -= tofree; - memmove(ac->entry, &(ac->entry[tofree]), sizeof(void *) * ac->avail); -} - -static void do_drain(void *arg) -{ - struct kmem_cache *cachep = arg; - struct array_cache *ac; - int node = numa_mem_id(); - struct kmem_cache_node *n; - LIST_HEAD(list); - - check_irq_off(); - ac = cpu_cache_get(cachep); - n = get_node(cachep, node); - raw_spin_lock(&n->list_lock); - free_block(cachep, ac->entry, ac->avail, node, &list); - raw_spin_unlock(&n->list_lock); - ac->avail = 0; - slabs_destroy(cachep, &list); -} - -static void drain_cpu_caches(struct kmem_cache *cachep) -{ - struct kmem_cache_node *n; - int node; - LIST_HEAD(list); - - on_each_cpu(do_drain, cachep, 1); - check_irq_on(); - for_each_kmem_cache_node(cachep, node, n) - if (n->alien) - drain_alien_cache(cachep, n->alien); - - for_each_kmem_cache_node(cachep, node, n) { - raw_spin_lock_irq(&n->list_lock); - drain_array_locked(cachep, n->shared, node, true, &list); - raw_spin_unlock_irq(&n->list_lock); - - slabs_destroy(cachep, &list); - } -} - -/* - * Remove slabs from the list of free slabs. - * Specify the number of slabs to drain in tofree. - * - * Returns the actual number of slabs released. - */ -static int drain_freelist(struct kmem_cache *cache, - struct kmem_cache_node *n, int tofree) -{ - struct list_head *p; - int nr_freed; - struct slab *slab; - - nr_freed = 0; - while (nr_freed < tofree && !list_empty(&n->slabs_free)) { - - raw_spin_lock_irq(&n->list_lock); - p = n->slabs_free.prev; - if (p == &n->slabs_free) { - raw_spin_unlock_irq(&n->list_lock); - goto out; - } - - slab = list_entry(p, struct slab, slab_list); - list_del(&slab->slab_list); - n->free_slabs--; - n->total_slabs--; - /* - * Safe to drop the lock. The slab is no longer linked - * to the cache. - */ - n->free_objects -= cache->num; - raw_spin_unlock_irq(&n->list_lock); - slab_destroy(cache, slab); - nr_freed++; - - cond_resched(); - } -out: - return nr_freed; -} - -bool __kmem_cache_empty(struct kmem_cache *s) -{ - int node; - struct kmem_cache_node *n; - - for_each_kmem_cache_node(s, node, n) - if (!list_empty(&n->slabs_full) || - !list_empty(&n->slabs_partial)) - return false; - return true; -} - -int __kmem_cache_shrink(struct kmem_cache *cachep) -{ - int ret = 0; - int node; - struct kmem_cache_node *n; - - drain_cpu_caches(cachep); - - check_irq_on(); - for_each_kmem_cache_node(cachep, node, n) { - drain_freelist(cachep, n, INT_MAX); - - ret += !list_empty(&n->slabs_full) || - !list_empty(&n->slabs_partial); - } - return (ret ? 1 : 0); -} - -int __kmem_cache_shutdown(struct kmem_cache *cachep) -{ - return __kmem_cache_shrink(cachep); -} - -void __kmem_cache_release(struct kmem_cache *cachep) -{ - int i; - struct kmem_cache_node *n; - - cache_random_seq_destroy(cachep); - - free_percpu(cachep->cpu_cache); - - /* NUMA: free the node structures */ - for_each_kmem_cache_node(cachep, i, n) { - kfree(n->shared); - free_alien_cache(n->alien); - kfree(n); - cachep->node[i] = NULL; - } -} - -/* - * Get the memory for a slab management obj. - * - * For a slab cache when the slab descriptor is off-slab, the - * slab descriptor can't come from the same cache which is being created, - * Because if it is the case, that means we defer the creation of - * the kmalloc_{dma,}_cache of size sizeof(slab descriptor) to this point. - * And we eventually call down to __kmem_cache_create(), which - * in turn looks up in the kmalloc_{dma,}_caches for the desired-size one. - * This is a "chicken-and-egg" problem. - * - * So the off-slab slab descriptor shall come from the kmalloc_{dma,}_caches, - * which are all initialized during kmem_cache_init(). - */ -static void *alloc_slabmgmt(struct kmem_cache *cachep, - struct slab *slab, int colour_off, - gfp_t local_flags, int nodeid) -{ - void *freelist; - void *addr = slab_address(slab); - - slab->s_mem = addr + colour_off; - slab->active = 0; - - if (OBJFREELIST_SLAB(cachep)) - freelist = NULL; - else if (OFF_SLAB(cachep)) { - /* Slab management obj is off-slab. */ - freelist = kmalloc_node(cachep->freelist_size, - local_flags, nodeid); - } else { - /* We will use last bytes at the slab for freelist */ - freelist = addr + (PAGE_SIZE << cachep->gfporder) - - cachep->freelist_size; - } - - return freelist; -} - -static inline freelist_idx_t get_free_obj(struct slab *slab, unsigned int idx) -{ - return ((freelist_idx_t *) slab->freelist)[idx]; -} - -static inline void set_free_obj(struct slab *slab, - unsigned int idx, freelist_idx_t val) -{ - ((freelist_idx_t *)(slab->freelist))[idx] = val; -} - -static void cache_init_objs_debug(struct kmem_cache *cachep, struct slab *slab) -{ -#if DEBUG - int i; - - for (i = 0; i < cachep->num; i++) { - void *objp = index_to_obj(cachep, slab, i); - - if (cachep->flags & SLAB_STORE_USER) - *dbg_userword(cachep, objp) = NULL; - - if (cachep->flags & SLAB_RED_ZONE) { - *dbg_redzone1(cachep, objp) = RED_INACTIVE; - *dbg_redzone2(cachep, objp) = RED_INACTIVE; - } - /* - * Constructors are not allowed to allocate memory from the same - * cache which they are a constructor for. Otherwise, deadlock. - * They must also be threaded. - */ - if (cachep->ctor && !(cachep->flags & SLAB_POISON)) { - kasan_unpoison_object_data(cachep, - objp + obj_offset(cachep)); - cachep->ctor(objp + obj_offset(cachep)); - kasan_poison_object_data( - cachep, objp + obj_offset(cachep)); - } - - if (cachep->flags & SLAB_RED_ZONE) { - if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) - slab_error(cachep, "constructor overwrote the end of an object"); - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) - slab_error(cachep, "constructor overwrote the start of an object"); - } - /* need to poison the objs? */ - if (cachep->flags & SLAB_POISON) { - poison_obj(cachep, objp, POISON_FREE); - slab_kernel_map(cachep, objp, 0); - } - } -#endif -} - -#ifdef CONFIG_SLAB_FREELIST_RANDOM -/* Hold information during a freelist initialization */ -union freelist_init_state { - struct { - unsigned int pos; - unsigned int *list; - unsigned int count; - }; - struct rnd_state rnd_state; -}; - -/* - * Initialize the state based on the randomization method available. - * return true if the pre-computed list is available, false otherwise. - */ -static bool freelist_state_initialize(union freelist_init_state *state, - struct kmem_cache *cachep, - unsigned int count) -{ - bool ret; - unsigned int rand; - - /* Use best entropy available to define a random shift */ - rand = get_random_u32(); - - /* Use a random state if the pre-computed list is not available */ - if (!cachep->random_seq) { - prandom_seed_state(&state->rnd_state, rand); - ret = false; - } else { - state->list = cachep->random_seq; - state->count = count; - state->pos = rand % count; - ret = true; - } - return ret; -} - -/* Get the next entry on the list and randomize it using a random shift */ -static freelist_idx_t next_random_slot(union freelist_init_state *state) -{ - if (state->pos >= state->count) - state->pos = 0; - return state->list[state->pos++]; -} - -/* Swap two freelist entries */ -static void swap_free_obj(struct slab *slab, unsigned int a, unsigned int b) -{ - swap(((freelist_idx_t *) slab->freelist)[a], - ((freelist_idx_t *) slab->freelist)[b]); -} - -/* - * Shuffle the freelist initialization state based on pre-computed lists. - * return true if the list was successfully shuffled, false otherwise. - */ -static bool shuffle_freelist(struct kmem_cache *cachep, struct slab *slab) -{ - unsigned int objfreelist = 0, i, rand, count = cachep->num; - union freelist_init_state state; - bool precomputed; - - if (count < 2) - return false; - - precomputed = freelist_state_initialize(&state, cachep, count); - - /* Take a random entry as the objfreelist */ - if (OBJFREELIST_SLAB(cachep)) { - if (!precomputed) - objfreelist = count - 1; - else - objfreelist = next_random_slot(&state); - slab->freelist = index_to_obj(cachep, slab, objfreelist) + - obj_offset(cachep); - count--; - } - - /* - * On early boot, generate the list dynamically. - * Later use a pre-computed list for speed. - */ - if (!precomputed) { - for (i = 0; i < count; i++) - set_free_obj(slab, i, i); - - /* Fisher-Yates shuffle */ - for (i = count - 1; i > 0; i--) { - rand = prandom_u32_state(&state.rnd_state); - rand %= (i + 1); - swap_free_obj(slab, i, rand); - } - } else { - for (i = 0; i < count; i++) - set_free_obj(slab, i, next_random_slot(&state)); - } - - if (OBJFREELIST_SLAB(cachep)) - set_free_obj(slab, cachep->num - 1, objfreelist); - - return true; -} -#else -static inline bool shuffle_freelist(struct kmem_cache *cachep, - struct slab *slab) -{ - return false; -} -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ - -static void cache_init_objs(struct kmem_cache *cachep, - struct slab *slab) -{ - int i; - void *objp; - bool shuffled; - - cache_init_objs_debug(cachep, slab); - - /* Try to randomize the freelist if enabled */ - shuffled = shuffle_freelist(cachep, slab); - - if (!shuffled && OBJFREELIST_SLAB(cachep)) { - slab->freelist = index_to_obj(cachep, slab, cachep->num - 1) + - obj_offset(cachep); - } - - for (i = 0; i < cachep->num; i++) { - objp = index_to_obj(cachep, slab, i); - objp = kasan_init_slab_obj(cachep, objp); - - /* constructor could break poison info */ - if (DEBUG == 0 && cachep->ctor) { - kasan_unpoison_object_data(cachep, objp); - cachep->ctor(objp); - kasan_poison_object_data(cachep, objp); - } - - if (!shuffled) - set_free_obj(slab, i, i); - } -} - -static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slab) -{ - void *objp; - - objp = index_to_obj(cachep, slab, get_free_obj(slab, slab->active)); - slab->active++; - - return objp; -} - -static void slab_put_obj(struct kmem_cache *cachep, - struct slab *slab, void *objp) -{ - unsigned int objnr = obj_to_index(cachep, slab, objp); -#if DEBUG - unsigned int i; - - /* Verify double free bug */ - for (i = slab->active; i < cachep->num; i++) { - if (get_free_obj(slab, i) == objnr) { - pr_err("slab: double free detected in cache '%s', objp %px\n", - cachep->name, objp); - BUG(); - } - } -#endif - slab->active--; - if (!slab->freelist) - slab->freelist = objp + obj_offset(cachep); - - set_free_obj(slab, slab->active, objnr); -} - -/* - * Grow (by 1) the number of slabs within a cache. This is called by - * kmem_cache_alloc() when there are no active objs left in a cache. - */ -static struct slab *cache_grow_begin(struct kmem_cache *cachep, - gfp_t flags, int nodeid) -{ - void *freelist; - size_t offset; - gfp_t local_flags; - int slab_node; - struct kmem_cache_node *n; - struct slab *slab; - - /* - * Be lazy and only check for valid flags here, keeping it out of the - * critical path in kmem_cache_alloc(). - */ - if (unlikely(flags & GFP_SLAB_BUG_MASK)) - flags = kmalloc_fix_flags(flags); - - WARN_ON_ONCE(cachep->ctor && (flags & __GFP_ZERO)); - local_flags = flags & (GFP_CONSTRAINT_MASK|GFP_RECLAIM_MASK); - - check_irq_off(); - if (gfpflags_allow_blocking(local_flags)) - local_irq_enable(); - - /* - * Get mem for the objs. Attempt to allocate a physical page from - * 'nodeid'. - */ - slab = kmem_getpages(cachep, local_flags, nodeid); - if (!slab) - goto failed; - - slab_node = slab_nid(slab); - n = get_node(cachep, slab_node); - - /* Get colour for the slab, and cal the next value. */ - n->colour_next++; - if (n->colour_next >= cachep->colour) - n->colour_next = 0; - - offset = n->colour_next; - if (offset >= cachep->colour) - offset = 0; - - offset *= cachep->colour_off; - - /* - * Call kasan_poison_slab() before calling alloc_slabmgmt(), so - * page_address() in the latter returns a non-tagged pointer, - * as it should be for slab pages. - */ - kasan_poison_slab(slab); - - /* Get slab management. */ - freelist = alloc_slabmgmt(cachep, slab, offset, - local_flags & ~GFP_CONSTRAINT_MASK, slab_node); - if (OFF_SLAB(cachep) && !freelist) - goto opps1; - - slab->slab_cache = cachep; - slab->freelist = freelist; - - cache_init_objs(cachep, slab); - - if (gfpflags_allow_blocking(local_flags)) - local_irq_disable(); - - return slab; - -opps1: - kmem_freepages(cachep, slab); -failed: - if (gfpflags_allow_blocking(local_flags)) - local_irq_disable(); - return NULL; -} - -static void cache_grow_end(struct kmem_cache *cachep, struct slab *slab) -{ - struct kmem_cache_node *n; - void *list = NULL; - - check_irq_off(); - - if (!slab) - return; - - INIT_LIST_HEAD(&slab->slab_list); - n = get_node(cachep, slab_nid(slab)); - - raw_spin_lock(&n->list_lock); - n->total_slabs++; - if (!slab->active) { - list_add_tail(&slab->slab_list, &n->slabs_free); - n->free_slabs++; - } else - fixup_slab_list(cachep, n, slab, &list); - - STATS_INC_GROWN(cachep); - n->free_objects += cachep->num - slab->active; - raw_spin_unlock(&n->list_lock); - - fixup_objfreelist_debug(cachep, &list); -} - -#if DEBUG - -/* - * Perform extra freeing checks: - * - detect bad pointers. - * - POISON/RED_ZONE checking - */ -static void kfree_debugcheck(const void *objp) -{ - if (!virt_addr_valid(objp)) { - pr_err("kfree_debugcheck: out of range ptr %lxh\n", - (unsigned long)objp); - BUG(); - } -} - -static inline void verify_redzone_free(struct kmem_cache *cache, void *obj) -{ - unsigned long long redzone1, redzone2; - - redzone1 = *dbg_redzone1(cache, obj); - redzone2 = *dbg_redzone2(cache, obj); - - /* - * Redzone is ok. - */ - if (redzone1 == RED_ACTIVE && redzone2 == RED_ACTIVE) - return; - - if (redzone1 == RED_INACTIVE && redzone2 == RED_INACTIVE) - slab_error(cache, "double free detected"); - else - slab_error(cache, "memory outside object was overwritten"); - - pr_err("%px: redzone 1:0x%llx, redzone 2:0x%llx\n", - obj, redzone1, redzone2); -} - -static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp, - unsigned long caller) -{ - unsigned int objnr; - struct slab *slab; - - BUG_ON(virt_to_cache(objp) != cachep); - - objp -= obj_offset(cachep); - kfree_debugcheck(objp); - slab = virt_to_slab(objp); - - if (cachep->flags & SLAB_RED_ZONE) { - verify_redzone_free(cachep, objp); - *dbg_redzone1(cachep, objp) = RED_INACTIVE; - *dbg_redzone2(cachep, objp) = RED_INACTIVE; - } - if (cachep->flags & SLAB_STORE_USER) - *dbg_userword(cachep, objp) = (void *)caller; - - objnr = obj_to_index(cachep, slab, objp); - - BUG_ON(objnr >= cachep->num); - BUG_ON(objp != index_to_obj(cachep, slab, objnr)); - - if (cachep->flags & SLAB_POISON) { - poison_obj(cachep, objp, POISON_FREE); - slab_kernel_map(cachep, objp, 0); - } - return objp; -} - -#else -#define kfree_debugcheck(x) do { } while(0) -#define cache_free_debugcheck(x, objp, z) (objp) -#endif - -static inline void fixup_objfreelist_debug(struct kmem_cache *cachep, - void **list) -{ -#if DEBUG - void *next = *list; - void *objp; - - while (next) { - objp = next - obj_offset(cachep); - next = *(void **)next; - poison_obj(cachep, objp, POISON_FREE); - } -#endif -} - -static inline void fixup_slab_list(struct kmem_cache *cachep, - struct kmem_cache_node *n, struct slab *slab, - void **list) -{ - /* move slabp to correct slabp list: */ - list_del(&slab->slab_list); - if (slab->active == cachep->num) { - list_add(&slab->slab_list, &n->slabs_full); - if (OBJFREELIST_SLAB(cachep)) { -#if DEBUG - /* Poisoning will be done without holding the lock */ - if (cachep->flags & SLAB_POISON) { - void **objp = slab->freelist; - - *objp = *list; - *list = objp; - } -#endif - slab->freelist = NULL; - } - } else - list_add(&slab->slab_list, &n->slabs_partial); -} - -/* Try to find non-pfmemalloc slab if needed */ -static noinline struct slab *get_valid_first_slab(struct kmem_cache_node *n, - struct slab *slab, bool pfmemalloc) -{ - if (!slab) - return NULL; - - if (pfmemalloc) - return slab; - - if (!slab_test_pfmemalloc(slab)) - return slab; - - /* No need to keep pfmemalloc slab if we have enough free objects */ - if (n->free_objects > n->free_limit) { - slab_clear_pfmemalloc(slab); - return slab; - } - - /* Move pfmemalloc slab to the end of list to speed up next search */ - list_del(&slab->slab_list); - if (!slab->active) { - list_add_tail(&slab->slab_list, &n->slabs_free); - n->free_slabs++; - } else - list_add_tail(&slab->slab_list, &n->slabs_partial); - - list_for_each_entry(slab, &n->slabs_partial, slab_list) { - if (!slab_test_pfmemalloc(slab)) - return slab; - } - - n->free_touched = 1; - list_for_each_entry(slab, &n->slabs_free, slab_list) { - if (!slab_test_pfmemalloc(slab)) { - n->free_slabs--; - return slab; - } - } - - return NULL; -} - -static struct slab *get_first_slab(struct kmem_cache_node *n, bool pfmemalloc) -{ - struct slab *slab; - - assert_raw_spin_locked(&n->list_lock); - slab = list_first_entry_or_null(&n->slabs_partial, struct slab, - slab_list); - if (!slab) { - n->free_touched = 1; - slab = list_first_entry_or_null(&n->slabs_free, struct slab, - slab_list); - if (slab) - n->free_slabs--; - } - - if (sk_memalloc_socks()) - slab = get_valid_first_slab(n, slab, pfmemalloc); - - return slab; -} - -static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep, - struct kmem_cache_node *n, gfp_t flags) -{ - struct slab *slab; - void *obj; - void *list = NULL; - - if (!gfp_pfmemalloc_allowed(flags)) - return NULL; - - raw_spin_lock(&n->list_lock); - slab = get_first_slab(n, true); - if (!slab) { - raw_spin_unlock(&n->list_lock); - return NULL; - } - - obj = slab_get_obj(cachep, slab); - n->free_objects--; - - fixup_slab_list(cachep, n, slab, &list); - - raw_spin_unlock(&n->list_lock); - fixup_objfreelist_debug(cachep, &list); - - return obj; -} - -/* - * Slab list should be fixed up by fixup_slab_list() for existing slab - * or cache_grow_end() for new slab - */ -static __always_inline int alloc_block(struct kmem_cache *cachep, - struct array_cache *ac, struct slab *slab, int batchcount) -{ - /* - * There must be at least one object available for - * allocation. - */ - BUG_ON(slab->active >= cachep->num); - - while (slab->active < cachep->num && batchcount--) { - STATS_INC_ALLOCED(cachep); - STATS_INC_ACTIVE(cachep); - STATS_SET_HIGH(cachep); - - ac->entry[ac->avail++] = slab_get_obj(cachep, slab); - } - - return batchcount; -} - -static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags) -{ - int batchcount; - struct kmem_cache_node *n; - struct array_cache *ac, *shared; - int node; - void *list = NULL; - struct slab *slab; - - check_irq_off(); - node = numa_mem_id(); - - ac = cpu_cache_get(cachep); - batchcount = ac->batchcount; - if (!ac->touched && batchcount > BATCHREFILL_LIMIT) { - /* - * If there was little recent activity on this cache, then - * perform only a partial refill. Otherwise we could generate - * refill bouncing. - */ - batchcount = BATCHREFILL_LIMIT; - } - n = get_node(cachep, node); - - BUG_ON(ac->avail > 0 || !n); - shared = READ_ONCE(n->shared); - if (!n->free_objects && (!shared || !shared->avail)) - goto direct_grow; - - raw_spin_lock(&n->list_lock); - shared = READ_ONCE(n->shared); - - /* See if we can refill from the shared array */ - if (shared && transfer_objects(ac, shared, batchcount)) { - shared->touched = 1; - goto alloc_done; - } - - while (batchcount > 0) { - /* Get slab alloc is to come from. */ - slab = get_first_slab(n, false); - if (!slab) - goto must_grow; - - check_spinlock_acquired(cachep); - - batchcount = alloc_block(cachep, ac, slab, batchcount); - fixup_slab_list(cachep, n, slab, &list); - } - -must_grow: - n->free_objects -= ac->avail; -alloc_done: - raw_spin_unlock(&n->list_lock); - fixup_objfreelist_debug(cachep, &list); - -direct_grow: - if (unlikely(!ac->avail)) { - /* Check if we can use obj in pfmemalloc slab */ - if (sk_memalloc_socks()) { - void *obj = cache_alloc_pfmemalloc(cachep, n, flags); - - if (obj) - return obj; - } - - slab = cache_grow_begin(cachep, gfp_exact_node(flags), node); - - /* - * cache_grow_begin() can reenable interrupts, - * then ac could change. - */ - ac = cpu_cache_get(cachep); - if (!ac->avail && slab) - alloc_block(cachep, ac, slab, batchcount); - cache_grow_end(cachep, slab); - - if (!ac->avail) - return NULL; - } - ac->touched = 1; - - return ac->entry[--ac->avail]; -} - -#if DEBUG -static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, - gfp_t flags, void *objp, unsigned long caller) -{ - WARN_ON_ONCE(cachep->ctor && (flags & __GFP_ZERO)); - if (!objp || is_kfence_address(objp)) - return objp; - if (cachep->flags & SLAB_POISON) { - check_poison_obj(cachep, objp); - slab_kernel_map(cachep, objp, 1); - poison_obj(cachep, objp, POISON_INUSE); - } - if (cachep->flags & SLAB_STORE_USER) - *dbg_userword(cachep, objp) = (void *)caller; - - if (cachep->flags & SLAB_RED_ZONE) { - if (*dbg_redzone1(cachep, objp) != RED_INACTIVE || - *dbg_redzone2(cachep, objp) != RED_INACTIVE) { - slab_error(cachep, "double free, or memory outside object was overwritten"); - pr_err("%px: redzone 1:0x%llx, redzone 2:0x%llx\n", - objp, *dbg_redzone1(cachep, objp), - *dbg_redzone2(cachep, objp)); - } - *dbg_redzone1(cachep, objp) = RED_ACTIVE; - *dbg_redzone2(cachep, objp) = RED_ACTIVE; - } - - objp += obj_offset(cachep); - if (cachep->ctor && cachep->flags & SLAB_POISON) - cachep->ctor(objp); - if ((unsigned long)objp & (arch_slab_minalign() - 1)) { - pr_err("0x%px: not aligned to arch_slab_minalign()=%u\n", objp, - arch_slab_minalign()); - } - return objp; -} -#else -#define cache_alloc_debugcheck_after(a, b, objp, d) (objp) -#endif - -static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) -{ - void *objp; - struct array_cache *ac; - - check_irq_off(); - - ac = cpu_cache_get(cachep); - if (likely(ac->avail)) { - ac->touched = 1; - objp = ac->entry[--ac->avail]; - - STATS_INC_ALLOCHIT(cachep); - goto out; - } - - STATS_INC_ALLOCMISS(cachep); - objp = cache_alloc_refill(cachep, flags); - /* - * the 'ac' may be updated by cache_alloc_refill(), - * and kmemleak_erase() requires its correct value. - */ - ac = cpu_cache_get(cachep); - -out: - /* - * To avoid a false negative, if an object that is in one of the - * per-CPU caches is leaked, we need to make sure kmemleak doesn't - * treat the array pointers as a reference to the object. - */ - if (objp) - kmemleak_erase(&ac->entry[ac->avail]); - return objp; -} - -#ifdef CONFIG_NUMA -static void *____cache_alloc_node(struct kmem_cache *, gfp_t, int); - -/* - * Try allocating on another node if PFA_SPREAD_SLAB is a mempolicy is set. - * - * If we are in_interrupt, then process context, including cpusets and - * mempolicy, may not apply and should not be used for allocation policy. - */ -static void *alternate_node_alloc(struct kmem_cache *cachep, gfp_t flags) -{ - int nid_alloc, nid_here; - - if (in_interrupt() || (flags & __GFP_THISNODE)) - return NULL; - nid_alloc = nid_here = numa_mem_id(); - if (cpuset_do_slab_mem_spread() && (cachep->flags & SLAB_MEM_SPREAD)) - nid_alloc = cpuset_slab_spread_node(); - else if (current->mempolicy) - nid_alloc = mempolicy_slab_node(); - if (nid_alloc != nid_here) - return ____cache_alloc_node(cachep, flags, nid_alloc); - return NULL; -} - -/* - * Fallback function if there was no memory available and no objects on a - * certain node and fall back is permitted. First we scan all the - * available node for available objects. If that fails then we - * perform an allocation without specifying a node. This allows the page - * allocator to do its reclaim / fallback magic. We then insert the - * slab into the proper nodelist and then allocate from it. - */ -static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags) -{ - struct zonelist *zonelist; - struct zoneref *z; - struct zone *zone; - enum zone_type highest_zoneidx = gfp_zone(flags); - void *obj = NULL; - struct slab *slab; - int nid; - unsigned int cpuset_mems_cookie; - - if (flags & __GFP_THISNODE) - return NULL; - -retry_cpuset: - cpuset_mems_cookie = read_mems_allowed_begin(); - zonelist = node_zonelist(mempolicy_slab_node(), flags); - -retry: - /* - * Look through allowed nodes for objects available - * from existing per node queues. - */ - for_each_zone_zonelist(zone, z, zonelist, highest_zoneidx) { - nid = zone_to_nid(zone); - - if (cpuset_zone_allowed(zone, flags) && - get_node(cache, nid) && - get_node(cache, nid)->free_objects) { - obj = ____cache_alloc_node(cache, - gfp_exact_node(flags), nid); - if (obj) - break; - } - } - - if (!obj) { - /* - * This allocation will be performed within the constraints - * of the current cpuset / memory policy requirements. - * We may trigger various forms of reclaim on the allowed - * set and go into memory reserves if necessary. - */ - slab = cache_grow_begin(cache, flags, numa_mem_id()); - cache_grow_end(cache, slab); - if (slab) { - nid = slab_nid(slab); - obj = ____cache_alloc_node(cache, - gfp_exact_node(flags), nid); - - /* - * Another processor may allocate the objects in - * the slab since we are not holding any locks. - */ - if (!obj) - goto retry; - } - } - - if (unlikely(!obj && read_mems_allowed_retry(cpuset_mems_cookie))) - goto retry_cpuset; - return obj; -} - -/* - * An interface to enable slab creation on nodeid - */ -static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, - int nodeid) -{ - struct slab *slab; - struct kmem_cache_node *n; - void *obj = NULL; - void *list = NULL; - - VM_BUG_ON(nodeid < 0 || nodeid >= MAX_NUMNODES); - n = get_node(cachep, nodeid); - BUG_ON(!n); - - check_irq_off(); - raw_spin_lock(&n->list_lock); - slab = get_first_slab(n, false); - if (!slab) - goto must_grow; - - check_spinlock_acquired_node(cachep, nodeid); - - STATS_INC_NODEALLOCS(cachep); - STATS_INC_ACTIVE(cachep); - STATS_SET_HIGH(cachep); - - BUG_ON(slab->active == cachep->num); - - obj = slab_get_obj(cachep, slab); - n->free_objects--; - - fixup_slab_list(cachep, n, slab, &list); - - raw_spin_unlock(&n->list_lock); - fixup_objfreelist_debug(cachep, &list); - return obj; - -must_grow: - raw_spin_unlock(&n->list_lock); - slab = cache_grow_begin(cachep, gfp_exact_node(flags), nodeid); - if (slab) { - /* This slab isn't counted yet so don't update free_objects */ - obj = slab_get_obj(cachep, slab); - } - cache_grow_end(cachep, slab); - - return obj ? obj : fallback_alloc(cachep, flags); -} - -static __always_inline void * -__do_cache_alloc(struct kmem_cache *cachep, gfp_t flags, int nodeid) -{ - void *objp = NULL; - int slab_node = numa_mem_id(); - - if (nodeid == NUMA_NO_NODE) { - if (current->mempolicy || cpuset_do_slab_mem_spread()) { - objp = alternate_node_alloc(cachep, flags); - if (objp) - goto out; - } - /* - * Use the locally cached objects if possible. - * However ____cache_alloc does not allow fallback - * to other nodes. It may fail while we still have - * objects on other nodes available. - */ - objp = ____cache_alloc(cachep, flags); - nodeid = slab_node; - } else if (nodeid == slab_node) { - objp = ____cache_alloc(cachep, flags); - } else if (!get_node(cachep, nodeid)) { - /* Node not bootstrapped yet */ - objp = fallback_alloc(cachep, flags); - goto out; - } - - /* - * We may just have run out of memory on the local node. - * ____cache_alloc_node() knows how to locate memory on other nodes - */ - if (!objp) - objp = ____cache_alloc_node(cachep, flags, nodeid); -out: - return objp; -} -#else - -static __always_inline void * -__do_cache_alloc(struct kmem_cache *cachep, gfp_t flags, int nodeid __maybe_unused) -{ - return ____cache_alloc(cachep, flags); -} - -#endif /* CONFIG_NUMA */ - -static __always_inline void * -slab_alloc_node(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags, - int nodeid, size_t orig_size, unsigned long caller) -{ - unsigned long save_flags; - void *objp; - struct obj_cgroup *objcg = NULL; - bool init = false; - - flags &= gfp_allowed_mask; - cachep = slab_pre_alloc_hook(cachep, lru, &objcg, 1, flags); - if (unlikely(!cachep)) - return NULL; - - objp = kfence_alloc(cachep, orig_size, flags); - if (unlikely(objp)) - goto out; - - local_irq_save(save_flags); - objp = __do_cache_alloc(cachep, flags, nodeid); - local_irq_restore(save_flags); - objp = cache_alloc_debugcheck_after(cachep, flags, objp, caller); - prefetchw(objp); - init = slab_want_init_on_alloc(flags, cachep); - -out: - slab_post_alloc_hook(cachep, objcg, flags, 1, &objp, init, - cachep->object_size); - return objp; -} - -static __always_inline void * -slab_alloc(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags, - size_t orig_size, unsigned long caller) -{ - return slab_alloc_node(cachep, lru, flags, NUMA_NO_NODE, orig_size, - caller); -} - -/* - * Caller needs to acquire correct kmem_cache_node's list_lock - * @list: List of detached free slabs should be freed by caller - */ -static void free_block(struct kmem_cache *cachep, void **objpp, - int nr_objects, int node, struct list_head *list) -{ - int i; - struct kmem_cache_node *n = get_node(cachep, node); - struct slab *slab; - - n->free_objects += nr_objects; - - for (i = 0; i < nr_objects; i++) { - void *objp; - struct slab *slab; - - objp = objpp[i]; - - slab = virt_to_slab(objp); - list_del(&slab->slab_list); - check_spinlock_acquired_node(cachep, node); - slab_put_obj(cachep, slab, objp); - STATS_DEC_ACTIVE(cachep); - - /* fixup slab chains */ - if (slab->active == 0) { - list_add(&slab->slab_list, &n->slabs_free); - n->free_slabs++; - } else { - /* Unconditionally move a slab to the end of the - * partial list on free - maximum time for the - * other objects to be freed, too. - */ - list_add_tail(&slab->slab_list, &n->slabs_partial); - } - } - - while (n->free_objects > n->free_limit && !list_empty(&n->slabs_free)) { - n->free_objects -= cachep->num; - - slab = list_last_entry(&n->slabs_free, struct slab, slab_list); - list_move(&slab->slab_list, list); - n->free_slabs--; - n->total_slabs--; - } -} - -static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) -{ - int batchcount; - struct kmem_cache_node *n; - int node = numa_mem_id(); - LIST_HEAD(list); - - batchcount = ac->batchcount; - - check_irq_off(); - n = get_node(cachep, node); - raw_spin_lock(&n->list_lock); - if (n->shared) { - struct array_cache *shared_array = n->shared; - int max = shared_array->limit - shared_array->avail; - if (max) { - if (batchcount > max) - batchcount = max; - memcpy(&(shared_array->entry[shared_array->avail]), - ac->entry, sizeof(void *) * batchcount); - shared_array->avail += batchcount; - goto free_done; - } - } - - free_block(cachep, ac->entry, batchcount, node, &list); -free_done: -#if STATS - { - int i = 0; - struct slab *slab; - - list_for_each_entry(slab, &n->slabs_free, slab_list) { - BUG_ON(slab->active); - - i++; - } - STATS_SET_FREEABLE(cachep, i); - } -#endif - raw_spin_unlock(&n->list_lock); - ac->avail -= batchcount; - memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail); - slabs_destroy(cachep, &list); -} - -/* - * Release an obj back to its cache. If the obj has a constructed state, it must - * be in this state _before_ it is released. Called with disabled ints. - */ -static __always_inline void __cache_free(struct kmem_cache *cachep, void *objp, - unsigned long caller) -{ - bool init; - - memcg_slab_free_hook(cachep, virt_to_slab(objp), &objp, 1); - - if (is_kfence_address(objp)) { - kmemleak_free_recursive(objp, cachep->flags); - __kfence_free(objp); - return; - } - - /* - * As memory initialization might be integrated into KASAN, - * kasan_slab_free and initialization memset must be - * kept together to avoid discrepancies in behavior. - */ - init = slab_want_init_on_free(cachep); - if (init && !kasan_has_integrated_init()) - memset(objp, 0, cachep->object_size); - /* KASAN might put objp into memory quarantine, delaying its reuse. */ - if (kasan_slab_free(cachep, objp, init)) - return; - - /* Use KCSAN to help debug racy use-after-free. */ - if (!(cachep->flags & SLAB_TYPESAFE_BY_RCU)) - __kcsan_check_access(objp, cachep->object_size, - KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ASSERT); - - ___cache_free(cachep, objp, caller); -} - -void ___cache_free(struct kmem_cache *cachep, void *objp, - unsigned long caller) -{ - struct array_cache *ac = cpu_cache_get(cachep); - - check_irq_off(); - kmemleak_free_recursive(objp, cachep->flags); - objp = cache_free_debugcheck(cachep, objp, caller); - - /* - * Skip calling cache_free_alien() when the platform is not numa. - * This will avoid cache misses that happen while accessing slabp (which - * is per page memory reference) to get nodeid. Instead use a global - * variable to skip the call, which is mostly likely to be present in - * the cache. - */ - if (nr_online_nodes > 1 && cache_free_alien(cachep, objp)) - return; - - if (ac->avail < ac->limit) { - STATS_INC_FREEHIT(cachep); - } else { - STATS_INC_FREEMISS(cachep); - cache_flusharray(cachep, ac); - } - - if (sk_memalloc_socks()) { - struct slab *slab = virt_to_slab(objp); - - if (unlikely(slab_test_pfmemalloc(slab))) { - cache_free_pfmemalloc(cachep, slab, objp); - return; - } - } - - __free_one(ac, objp); -} - -static __always_inline -void *__kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, - gfp_t flags) -{ - void *ret = slab_alloc(cachep, lru, flags, cachep->object_size, _RET_IP_); - - trace_kmem_cache_alloc(_RET_IP_, ret, cachep, flags, NUMA_NO_NODE); - - return ret; -} - -void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) -{ - return __kmem_cache_alloc_lru(cachep, NULL, flags); -} -EXPORT_SYMBOL(kmem_cache_alloc); - -void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, - gfp_t flags) -{ - return __kmem_cache_alloc_lru(cachep, lru, flags); -} -EXPORT_SYMBOL(kmem_cache_alloc_lru); - -static __always_inline void -cache_alloc_debugcheck_after_bulk(struct kmem_cache *s, gfp_t flags, - size_t size, void **p, unsigned long caller) -{ - size_t i; - - for (i = 0; i < size; i++) - p[i] = cache_alloc_debugcheck_after(s, flags, p[i], caller); -} - -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, - void **p) -{ - struct obj_cgroup *objcg = NULL; - unsigned long irqflags; - size_t i; - - s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); - if (!s) - return 0; - - local_irq_save(irqflags); - for (i = 0; i < size; i++) { - void *objp = kfence_alloc(s, s->object_size, flags) ?: - __do_cache_alloc(s, flags, NUMA_NO_NODE); - - if (unlikely(!objp)) - goto error; - p[i] = objp; - } - local_irq_restore(irqflags); - - cache_alloc_debugcheck_after_bulk(s, flags, size, p, _RET_IP_); - - /* - * memcg and kmem_cache debug support and memory initialization. - * Done outside of the IRQ disabled section. - */ - slab_post_alloc_hook(s, objcg, flags, size, p, - slab_want_init_on_alloc(flags, s), s->object_size); - /* FIXME: Trace call missing. Christoph would like a bulk variant */ - return size; -error: - local_irq_restore(irqflags); - cache_alloc_debugcheck_after_bulk(s, flags, i, p, _RET_IP_); - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); - kmem_cache_free_bulk(s, i, p); - return 0; -} -EXPORT_SYMBOL(kmem_cache_alloc_bulk); - -/** - * kmem_cache_alloc_node - Allocate an object on the specified node - * @cachep: The cache to allocate from. - * @flags: See kmalloc(). - * @nodeid: node number of the target node. - * - * Identical to kmem_cache_alloc but it will allocate memory on the given - * node, which can improve the performance for cpu bound structures. - * - * Fallback to other node is possible if __GFP_THISNODE is not set. - * - * Return: pointer to the new object or %NULL in case of error - */ -void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) -{ - void *ret = slab_alloc_node(cachep, NULL, flags, nodeid, cachep->object_size, _RET_IP_); - - trace_kmem_cache_alloc(_RET_IP_, ret, cachep, flags, nodeid); - - return ret; -} -EXPORT_SYMBOL(kmem_cache_alloc_node); - -void *__kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, - int nodeid, size_t orig_size, - unsigned long caller) -{ - return slab_alloc_node(cachep, NULL, flags, nodeid, - orig_size, caller); -} - -#ifdef CONFIG_PRINTK -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) -{ - struct kmem_cache *cachep; - unsigned int objnr; - void *objp; - - kpp->kp_ptr = object; - kpp->kp_slab = slab; - cachep = slab->slab_cache; - kpp->kp_slab_cache = cachep; - objp = object - obj_offset(cachep); - kpp->kp_data_offset = obj_offset(cachep); - slab = virt_to_slab(objp); - objnr = obj_to_index(cachep, slab, objp); - objp = index_to_obj(cachep, slab, objnr); - kpp->kp_objp = objp; - if (DEBUG && cachep->flags & SLAB_STORE_USER) - kpp->kp_ret = *dbg_userword(cachep, objp); -} -#endif - -static __always_inline -void __do_kmem_cache_free(struct kmem_cache *cachep, void *objp, - unsigned long caller) -{ - unsigned long flags; - - local_irq_save(flags); - debug_check_no_locks_freed(objp, cachep->object_size); - if (!(cachep->flags & SLAB_DEBUG_OBJECTS)) - debug_check_no_obj_freed(objp, cachep->object_size); - __cache_free(cachep, objp, caller); - local_irq_restore(flags); -} - -void __kmem_cache_free(struct kmem_cache *cachep, void *objp, - unsigned long caller) -{ - __do_kmem_cache_free(cachep, objp, caller); -} - -/** - * kmem_cache_free - Deallocate an object - * @cachep: The cache the allocation was from. - * @objp: The previously allocated object. - * - * Free an object which was previously allocated from this - * cache. - */ -void kmem_cache_free(struct kmem_cache *cachep, void *objp) -{ - cachep = cache_from_obj(cachep, objp); - if (!cachep) - return; - - trace_kmem_cache_free(_RET_IP_, objp, cachep); - __do_kmem_cache_free(cachep, objp, _RET_IP_); -} -EXPORT_SYMBOL(kmem_cache_free); - -void kmem_cache_free_bulk(struct kmem_cache *orig_s, size_t size, void **p) -{ - unsigned long flags; - - local_irq_save(flags); - for (int i = 0; i < size; i++) { - void *objp = p[i]; - struct kmem_cache *s; - - if (!orig_s) { - struct folio *folio = virt_to_folio(objp); - - /* called via kfree_bulk */ - if (!folio_test_slab(folio)) { - local_irq_restore(flags); - free_large_kmalloc(folio, objp); - local_irq_save(flags); - continue; - } - s = folio_slab(folio)->slab_cache; - } else { - s = cache_from_obj(orig_s, objp); - } - - if (!s) - continue; - - debug_check_no_locks_freed(objp, s->object_size); - if (!(s->flags & SLAB_DEBUG_OBJECTS)) - debug_check_no_obj_freed(objp, s->object_size); - - __cache_free(s, objp, _RET_IP_); - } - local_irq_restore(flags); - - /* FIXME: add tracing */ -} -EXPORT_SYMBOL(kmem_cache_free_bulk); - -/* - * This initializes kmem_cache_node or resizes various caches for all nodes. - */ -static int setup_kmem_cache_nodes(struct kmem_cache *cachep, gfp_t gfp) -{ - int ret; - int node; - struct kmem_cache_node *n; - - for_each_online_node(node) { - ret = setup_kmem_cache_node(cachep, node, gfp, true); - if (ret) - goto fail; - - } - - return 0; - -fail: - if (!cachep->list.next) { - /* Cache is not active yet. Roll back what we did */ - node--; - while (node >= 0) { - n = get_node(cachep, node); - if (n) { - kfree(n->shared); - free_alien_cache(n->alien); - kfree(n); - cachep->node[node] = NULL; - } - node--; - } - } - return -ENOMEM; -} - -/* Always called with the slab_mutex held */ -static int do_tune_cpucache(struct kmem_cache *cachep, int limit, - int batchcount, int shared, gfp_t gfp) -{ - struct array_cache __percpu *cpu_cache, *prev; - int cpu; - - cpu_cache = alloc_kmem_cache_cpus(cachep, limit, batchcount); - if (!cpu_cache) - return -ENOMEM; - - prev = cachep->cpu_cache; - cachep->cpu_cache = cpu_cache; - /* - * Without a previous cpu_cache there's no need to synchronize remote - * cpus, so skip the IPIs. - */ - if (prev) - kick_all_cpus_sync(); - - check_irq_on(); - cachep->batchcount = batchcount; - cachep->limit = limit; - cachep->shared = shared; - - if (!prev) - goto setup_node; - - for_each_online_cpu(cpu) { - LIST_HEAD(list); - int node; - struct kmem_cache_node *n; - struct array_cache *ac = per_cpu_ptr(prev, cpu); - - node = cpu_to_mem(cpu); - n = get_node(cachep, node); - raw_spin_lock_irq(&n->list_lock); - free_block(cachep, ac->entry, ac->avail, node, &list); - raw_spin_unlock_irq(&n->list_lock); - slabs_destroy(cachep, &list); - } - free_percpu(prev); - -setup_node: - return setup_kmem_cache_nodes(cachep, gfp); -} - -/* Called with slab_mutex held always */ -static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp) -{ - int err; - int limit = 0; - int shared = 0; - int batchcount = 0; - - err = cache_random_seq_create(cachep, cachep->num, gfp); - if (err) - goto end; - - /* - * The head array serves three purposes: - * - create a LIFO ordering, i.e. return objects that are cache-warm - * - reduce the number of spinlock operations. - * - reduce the number of linked list operations on the slab and - * bufctl chains: array operations are cheaper. - * The numbers are guessed, we should auto-tune as described by - * Bonwick. - */ - if (cachep->size > 131072) - limit = 1; - else if (cachep->size > PAGE_SIZE) - limit = 8; - else if (cachep->size > 1024) - limit = 24; - else if (cachep->size > 256) - limit = 54; - else - limit = 120; - - /* - * CPU bound tasks (e.g. network routing) can exhibit cpu bound - * allocation behaviour: Most allocs on one cpu, most free operations - * on another cpu. For these cases, an efficient object passing between - * cpus is necessary. This is provided by a shared array. The array - * replaces Bonwick's magazine layer. - * On uniprocessor, it's functionally equivalent (but less efficient) - * to a larger limit. Thus disabled by default. - */ - shared = 0; - if (cachep->size <= PAGE_SIZE && num_possible_cpus() > 1) - shared = 8; - -#if DEBUG - /* - * With debugging enabled, large batchcount lead to excessively long - * periods with disabled local interrupts. Limit the batchcount - */ - if (limit > 32) - limit = 32; -#endif - batchcount = (limit + 1) / 2; - err = do_tune_cpucache(cachep, limit, batchcount, shared, gfp); -end: - if (err) - pr_err("enable_cpucache failed for %s, error %d\n", - cachep->name, -err); - return err; -} - -/* - * Drain an array if it contains any elements taking the node lock only if - * necessary. Note that the node listlock also protects the array_cache - * if drain_array() is used on the shared array. - */ -static void drain_array(struct kmem_cache *cachep, struct kmem_cache_node *n, - struct array_cache *ac, int node) -{ - LIST_HEAD(list); - - /* ac from n->shared can be freed if we don't hold the slab_mutex. */ - check_mutex_acquired(); - - if (!ac || !ac->avail) - return; - - if (ac->touched) { - ac->touched = 0; - return; - } - - raw_spin_lock_irq(&n->list_lock); - drain_array_locked(cachep, ac, node, false, &list); - raw_spin_unlock_irq(&n->list_lock); - - slabs_destroy(cachep, &list); -} - -/** - * cache_reap - Reclaim memory from caches. - * @w: work descriptor - * - * Called from workqueue/eventd every few seconds. - * Purpose: - * - clear the per-cpu caches for this CPU. - * - return freeable pages to the main free memory pool. - * - * If we cannot acquire the cache chain mutex then just give up - we'll try - * again on the next iteration. - */ -static void cache_reap(struct work_struct *w) -{ - struct kmem_cache *searchp; - struct kmem_cache_node *n; - int node = numa_mem_id(); - struct delayed_work *work = to_delayed_work(w); - - if (!mutex_trylock(&slab_mutex)) - /* Give up. Setup the next iteration. */ - goto out; - - list_for_each_entry(searchp, &slab_caches, list) { - check_irq_on(); - - /* - * We only take the node lock if absolutely necessary and we - * have established with reasonable certainty that - * we can do some work if the lock was obtained. - */ - n = get_node(searchp, node); - - reap_alien(searchp, n); - - drain_array(searchp, n, cpu_cache_get(searchp), node); - - /* - * These are racy checks but it does not matter - * if we skip one check or scan twice. - */ - if (time_after(n->next_reap, jiffies)) - goto next; - - n->next_reap = jiffies + REAPTIMEOUT_NODE; - - drain_array(searchp, n, n->shared, node); - - if (n->free_touched) - n->free_touched = 0; - else { - int freed; - - freed = drain_freelist(searchp, n, (n->free_limit + - 5 * searchp->num - 1) / (5 * searchp->num)); - STATS_ADD_REAPED(searchp, freed); - } -next: - cond_resched(); - } - check_irq_on(); - mutex_unlock(&slab_mutex); - next_reap_node(); -out: - /* Set up the next iteration */ - schedule_delayed_work_on(smp_processor_id(), work, - round_jiffies_relative(REAPTIMEOUT_AC)); -} - -void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo) -{ - unsigned long active_objs, num_objs, active_slabs; - unsigned long total_slabs = 0, free_objs = 0, shared_avail = 0; - unsigned long free_slabs = 0; - int node; - struct kmem_cache_node *n; - - for_each_kmem_cache_node(cachep, node, n) { - check_irq_on(); - raw_spin_lock_irq(&n->list_lock); - - total_slabs += n->total_slabs; - free_slabs += n->free_slabs; - free_objs += n->free_objects; - - if (n->shared) - shared_avail += n->shared->avail; - - raw_spin_unlock_irq(&n->list_lock); - } - num_objs = total_slabs * cachep->num; - active_slabs = total_slabs - free_slabs; - active_objs = num_objs - free_objs; - - sinfo->active_objs = active_objs; - sinfo->num_objs = num_objs; - sinfo->active_slabs = active_slabs; - sinfo->num_slabs = total_slabs; - sinfo->shared_avail = shared_avail; - sinfo->limit = cachep->limit; - sinfo->batchcount = cachep->batchcount; - sinfo->shared = cachep->shared; - sinfo->objects_per_slab = cachep->num; - sinfo->cache_order = cachep->gfporder; -} - -void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *cachep) -{ -#if STATS - { /* node stats */ - unsigned long high = cachep->high_mark; - unsigned long allocs = cachep->num_allocations; - unsigned long grown = cachep->grown; - unsigned long reaped = cachep->reaped; - unsigned long errors = cachep->errors; - unsigned long max_freeable = cachep->max_freeable; - unsigned long node_allocs = cachep->node_allocs; - unsigned long node_frees = cachep->node_frees; - unsigned long overflows = cachep->node_overflow; - - seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu %4lu %4lu %4lu %4lu %4lu", - allocs, high, grown, - reaped, errors, max_freeable, node_allocs, - node_frees, overflows); - } - /* cpu stats */ - { - unsigned long allochit = atomic_read(&cachep->allochit); - unsigned long allocmiss = atomic_read(&cachep->allocmiss); - unsigned long freehit = atomic_read(&cachep->freehit); - unsigned long freemiss = atomic_read(&cachep->freemiss); - - seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu", - allochit, allocmiss, freehit, freemiss); - } -#endif -} - -#define MAX_SLABINFO_WRITE 128 -/** - * slabinfo_write - Tuning for the slab allocator - * @file: unused - * @buffer: user buffer - * @count: data length - * @ppos: unused - * - * Return: %0 on success, negative error code otherwise. - */ -ssize_t slabinfo_write(struct file *file, const char __user *buffer, - size_t count, loff_t *ppos) -{ - char kbuf[MAX_SLABINFO_WRITE + 1], *tmp; - int limit, batchcount, shared, res; - struct kmem_cache *cachep; - - if (count > MAX_SLABINFO_WRITE) - return -EINVAL; - if (copy_from_user(&kbuf, buffer, count)) - return -EFAULT; - kbuf[MAX_SLABINFO_WRITE] = '\0'; - - tmp = strchr(kbuf, ' '); - if (!tmp) - return -EINVAL; - *tmp = '\0'; - tmp++; - if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3) - return -EINVAL; - - /* Find the cache in the chain of caches. */ - mutex_lock(&slab_mutex); - res = -EINVAL; - list_for_each_entry(cachep, &slab_caches, list) { - if (!strcmp(cachep->name, kbuf)) { - if (limit < 1 || batchcount < 1 || - batchcount > limit || shared < 0) { - res = 0; - } else { - res = do_tune_cpucache(cachep, limit, - batchcount, shared, - GFP_KERNEL); - } - break; - } - } - mutex_unlock(&slab_mutex); - if (res >= 0) - res = count; - return res; -} - -#ifdef CONFIG_HARDENED_USERCOPY -/* - * Rejects incorrectly sized objects and objects that are to be copied - * to/from userspace but do not fall entirely within the containing slab - * cache's usercopy region. - * - * Returns NULL if check passes, otherwise const char * to name of cache - * to indicate an error. - */ -void __check_heap_object(const void *ptr, unsigned long n, - const struct slab *slab, bool to_user) -{ - struct kmem_cache *cachep; - unsigned int objnr; - unsigned long offset; - - ptr = kasan_reset_tag(ptr); - - /* Find and validate object. */ - cachep = slab->slab_cache; - objnr = obj_to_index(cachep, slab, (void *)ptr); - BUG_ON(objnr >= cachep->num); - - /* Find offset within object. */ - if (is_kfence_address(ptr)) - offset = ptr - kfence_object_start(ptr); - else - offset = ptr - index_to_obj(cachep, slab, objnr) - obj_offset(cachep); - - /* Allow address range falling entirely within usercopy region. */ - if (offset >= cachep->useroffset && - offset - cachep->useroffset <= cachep->usersize && - n <= cachep->useroffset - offset + cachep->usersize) - return; - - usercopy_abort("SLAB object", cachep->name, to_user, offset, n); -} -#endif /* CONFIG_HARDENED_USERCOPY */ diff --git a/mm/slab.h b/mm/slab.h index 43966aa5fadf..53e97b7640e9 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -9,60 +9,12 @@ struct slab { unsigned long __page_flags; -#if defined(CONFIG_SLAB) - - struct kmem_cache *slab_cache; - union { - struct { - struct list_head slab_list; - void *freelist; /* array of free object indexes */ - void *s_mem; /* first object */ - }; - struct rcu_head rcu_head; - }; - unsigned int active; - -#elif defined(CONFIG_SLUB) - - struct kmem_cache *slab_cache; - union { - struct { - union { - struct list_head slab_list; -#ifdef CONFIG_SLUB_CPU_PARTIAL - struct { - struct slab *next; - int slabs; /* Nr of slabs left */ - }; -#endif - }; - /* Double-word boundary */ - void *freelist; /* first free object */ - union { - unsigned long counters; - struct { - unsigned inuse:16; - unsigned objects:15; - unsigned frozen:1; - }; - }; - }; - struct rcu_head rcu_head; - }; - unsigned int __unused; - -#elif defined(CONFIG_SLOB) - struct list_head slab_list; void *__unused_1; void *freelist; /* first free block */ long units; unsigned int __unused_2; -#else -#error "Unexpected slab allocator configured" -#endif - atomic_t __page_refcount; #ifdef CONFIG_MEMCG unsigned long memcg_data; @@ -72,20 +24,13 @@ struct slab { #define SLAB_MATCH(pg, sl) \ static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl)) SLAB_MATCH(flags, __page_flags); -#ifndef CONFIG_SLOB -SLAB_MATCH(compound_head, slab_cache); /* Ensure bit 0 is clear */ -#else SLAB_MATCH(compound_head, slab_list); /* Ensure bit 0 is clear */ -#endif SLAB_MATCH(_refcount, __page_refcount); #ifdef CONFIG_MEMCG SLAB_MATCH(memcg_data, memcg_data); #endif #undef SLAB_MATCH static_assert(sizeof(struct slab) <= sizeof(struct page)); -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && defined(CONFIG_SLUB) -static_assert(IS_ALIGNED(offsetof(struct slab, freelist), 2*sizeof(void *))); -#endif /** * folio_slab - Converts from folio to slab. @@ -200,7 +145,6 @@ static inline size_t slab_size(const struct slab *slab) return PAGE_SIZE << slab_order(slab); } -#ifdef CONFIG_SLOB /* * Common fields provided in kmem_cache by all slab allocators * This struct is either used directly by the allocator (SLOB) @@ -223,16 +167,6 @@ struct kmem_cache { struct list_head list; /* List of all slab caches on the system */ }; -#endif /* CONFIG_SLOB */ - -#ifdef CONFIG_SLAB -#include <linux/slab_def.h> -#endif - -#ifdef CONFIG_SLUB -#include <linux/slub_def.h> -#endif - #include <linux/memcontrol.h> #include <linux/fault-inject.h> #include <linux/kasan.h> @@ -268,26 +202,6 @@ extern struct list_head slab_caches; /* The slab cache that manages slab cache information */ extern struct kmem_cache *kmem_cache; -/* A table of kmalloc cache names and sizes */ -extern const struct kmalloc_info_struct { - const char *name[NR_KMALLOC_TYPES]; - unsigned int size; -} kmalloc_info[]; - -#ifndef CONFIG_SLOB -/* Kmalloc array related functions */ -void setup_kmalloc_cache_index_table(void); -void create_kmalloc_caches(slab_flags_t); - -/* Find the kmalloc slab corresponding for a certain size */ -struct kmem_cache *kmalloc_slab(size_t, gfp_t); - -void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, - int node, size_t orig_size, - unsigned long caller); -void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller); -#endif - gfp_t kmalloc_fix_flags(gfp_t flags); /* Functions provided by the slab allocators */ @@ -303,14 +217,6 @@ extern void create_boot_cache(struct kmem_cache *, const char *name, int slab_unmergeable(struct kmem_cache *s); struct kmem_cache *find_mergeable(unsigned size, unsigned align, slab_flags_t flags, const char *name, void (*ctor)(void *)); -#ifndef CONFIG_SLOB -struct kmem_cache * -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, - slab_flags_t flags, void (*ctor)(void *)); - -slab_flags_t kmem_cache_flags(unsigned int object_size, - slab_flags_t flags, const char *name); -#else static inline struct kmem_cache * __kmem_cache_alias(const char *name, unsigned int size, unsigned int align, slab_flags_t flags, void (*ctor)(void *)) @@ -321,15 +227,10 @@ static inline slab_flags_t kmem_cache_flags(unsigned int object_size, { return flags; } -#endif static inline bool is_kmalloc_cache(struct kmem_cache *s) { -#ifndef CONFIG_SLOB - return (s->flags & SLAB_KMALLOC); -#else return false; -#endif } /* Legal flag mask for kmem_cache_create(), for various configurations */ @@ -337,26 +238,9 @@ static inline bool is_kmalloc_cache(struct kmem_cache *s) SLAB_CACHE_DMA32 | SLAB_PANIC | \ SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS ) -#if defined(CONFIG_DEBUG_SLAB) -#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) -#elif defined(CONFIG_SLUB_DEBUG) -#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ - SLAB_TRACE | SLAB_CONSISTENCY_CHECKS) -#else #define SLAB_DEBUG_FLAGS (0) -#endif -#if defined(CONFIG_SLAB) -#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \ - SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \ - SLAB_ACCOUNT) -#elif defined(CONFIG_SLUB) -#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ - SLAB_TEMPORARY | SLAB_ACCOUNT | \ - SLAB_NO_USER_FLAGS | SLAB_KMALLOC) -#else #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE) -#endif /* Common flags available with current configuration */ #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS) @@ -409,19 +293,6 @@ static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s) NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B; } -#ifdef CONFIG_SLUB_DEBUG -#ifdef CONFIG_SLUB_DEBUG_ON -DECLARE_STATIC_KEY_TRUE(slub_debug_enabled); -#else -DECLARE_STATIC_KEY_FALSE(slub_debug_enabled); -#endif -extern void print_tracking(struct kmem_cache *s, void *object); -long validate_slab_cache(struct kmem_cache *s); -static inline bool __slub_debug_enabled(void) -{ - return static_branch_unlikely(&slub_debug_enabled); -} -#else static inline void print_tracking(struct kmem_cache *s, void *object) { } @@ -429,7 +300,6 @@ static inline bool __slub_debug_enabled(void) { return false; } -#endif /* * Returns true if any of the specified slub_debug flags is enabled for the @@ -438,160 +308,9 @@ static inline bool __slub_debug_enabled(void) */ static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags) { - if (IS_ENABLED(CONFIG_SLUB_DEBUG)) - VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS)); - if (__slub_debug_enabled()) - return s->flags & flags; return false; } -#ifdef CONFIG_MEMCG_KMEM -/* - * slab_objcgs - get the object cgroups vector associated with a slab - * @slab: a pointer to the slab struct - * - * Returns a pointer to the object cgroups vector associated with the slab, - * or NULL if no such vector has been associated yet. - */ -static inline struct obj_cgroup **slab_objcgs(struct slab *slab) -{ - unsigned long memcg_data = READ_ONCE(slab->memcg_data); - - VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), - slab_page(slab)); - VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, slab_page(slab)); - - return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); -} - -int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s, - gfp_t gfp, bool new_slab); -void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, - enum node_stat_item idx, int nr); - -static inline void memcg_free_slab_cgroups(struct slab *slab) -{ - kfree(slab_objcgs(slab)); - slab->memcg_data = 0; -} - -static inline size_t obj_full_size(struct kmem_cache *s) -{ - /* - * For each accounted object there is an extra space which is used - * to store obj_cgroup membership. Charge it too. - */ - return s->size + sizeof(struct obj_cgroup *); -} - -/* - * Returns false if the allocation should fail. - */ -static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, - struct list_lru *lru, - struct obj_cgroup **objcgp, - size_t objects, gfp_t flags) -{ - struct obj_cgroup *objcg; - - if (!memcg_kmem_online()) - return true; - - if (!(flags & __GFP_ACCOUNT) && !(s->flags & SLAB_ACCOUNT)) - return true; - - objcg = get_obj_cgroup_from_current(); - if (!objcg) - return true; - - if (lru) { - int ret; - struct mem_cgroup *memcg; - - memcg = get_mem_cgroup_from_objcg(objcg); - ret = memcg_list_lru_alloc(memcg, lru, flags); - css_put(&memcg->css); - - if (ret) - goto out; - } - - if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s))) - goto out; - - *objcgp = objcg; - return true; -out: - obj_cgroup_put(objcg); - return false; -} - -static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, - struct obj_cgroup *objcg, - gfp_t flags, size_t size, - void **p) -{ - struct slab *slab; - unsigned long off; - size_t i; - - if (!memcg_kmem_online() || !objcg) - return; - - for (i = 0; i < size; i++) { - if (likely(p[i])) { - slab = virt_to_slab(p[i]); - - if (!slab_objcgs(slab) && - memcg_alloc_slab_cgroups(slab, s, flags, - false)) { - obj_cgroup_uncharge(objcg, obj_full_size(s)); - continue; - } - - off = obj_to_index(s, slab, p[i]); - obj_cgroup_get(objcg); - slab_objcgs(slab)[off] = objcg; - mod_objcg_state(objcg, slab_pgdat(slab), - cache_vmstat_idx(s), obj_full_size(s)); - } else { - obj_cgroup_uncharge(objcg, obj_full_size(s)); - } - } - obj_cgroup_put(objcg); -} - -static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, - void **p, int objects) -{ - struct obj_cgroup **objcgs; - int i; - - if (!memcg_kmem_online()) - return; - - objcgs = slab_objcgs(slab); - if (!objcgs) - return; - - for (i = 0; i < objects; i++) { - struct obj_cgroup *objcg; - unsigned int off; - - off = obj_to_index(s, slab, p[i]); - objcg = objcgs[off]; - if (!objcg) - continue; - - objcgs[off] = NULL; - obj_cgroup_uncharge(objcg, obj_full_size(s)); - mod_objcg_state(objcg, slab_pgdat(slab), cache_vmstat_idx(s), - -obj_full_size(s)); - obj_cgroup_put(objcg); - } -} - -#else /* CONFIG_MEMCG_KMEM */ static inline struct obj_cgroup **slab_objcgs(struct slab *slab) { return NULL; @@ -632,90 +351,12 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, void **p, int objects) { } -#endif /* CONFIG_MEMCG_KMEM */ - -#ifndef CONFIG_SLOB -static inline struct kmem_cache *virt_to_cache(const void *obj) -{ - struct slab *slab; - - slab = virt_to_slab(obj); - if (WARN_ONCE(!slab, "%s: Object is not a Slab page!\n", - __func__)) - return NULL; - return slab->slab_cache; -} - -static __always_inline void account_slab(struct slab *slab, int order, - struct kmem_cache *s, gfp_t gfp) -{ - if (memcg_kmem_online() && (s->flags & SLAB_ACCOUNT)) - memcg_alloc_slab_cgroups(slab, s, gfp, true); - - mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), - PAGE_SIZE << order); -} - -static __always_inline void unaccount_slab(struct slab *slab, int order, - struct kmem_cache *s) -{ - if (memcg_kmem_online()) - memcg_free_slab_cgroups(slab); - - mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), - -(PAGE_SIZE << order)); -} - -static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) -{ - struct kmem_cache *cachep; - - if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && - !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) - return s; - - cachep = virt_to_cache(x); - if (WARN(cachep && cachep != s, - "%s: Wrong slab cache. %s but object is from %s\n", - __func__, s->name, cachep->name)) - print_tracking(cachep, x); - return cachep; -} - -void free_large_kmalloc(struct folio *folio, void *object); - -#endif /* CONFIG_SLOB */ size_t __ksize(const void *objp); static inline size_t slab_ksize(const struct kmem_cache *s) { -#ifndef CONFIG_SLUB return s->object_size; - -#else /* CONFIG_SLUB */ -# ifdef CONFIG_SLUB_DEBUG - /* - * Debugging requires use of the padding between object - * and whatever may come after it. - */ - if (s->flags & (SLAB_RED_ZONE | SLAB_POISON)) - return s->object_size; -# endif - if (s->flags & SLAB_KASAN) - return s->object_size; - /* - * If we have the need to store the freelist pointer - * back there or track user information then we can - * only use the space before that information. - */ - if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER)) - return s->inuse; - /* - * Else we can use all the padding etc for the allocation - */ - return s->size; -#endif } static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, @@ -777,77 +418,18 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, memcg_slab_post_alloc_hook(s, objcg, flags, size, p); } -#ifndef CONFIG_SLOB -/* - * The slab lists for all objects. - */ -struct kmem_cache_node { -#ifdef CONFIG_SLAB - raw_spinlock_t list_lock; - struct list_head slabs_partial; /* partial list first, better asm code */ - struct list_head slabs_full; - struct list_head slabs_free; - unsigned long total_slabs; /* length of all slab lists */ - unsigned long free_slabs; /* length of free slab list only */ - unsigned long free_objects; - unsigned int free_limit; - unsigned int colour_next; /* Per-node cache coloring */ - struct array_cache *shared; /* shared per node */ - struct alien_cache **alien; /* on other nodes */ - unsigned long next_reap; /* updated without locking */ - int free_touched; /* updated without locking */ -#endif - -#ifdef CONFIG_SLUB - spinlock_t list_lock; - unsigned long nr_partial; - struct list_head partial; -#ifdef CONFIG_SLUB_DEBUG - atomic_long_t nr_slabs; - atomic_long_t total_objects; - struct list_head full; -#endif -#endif - -}; - -static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node) -{ - return s->node[node]; -} - -/* - * Iterator over all nodes. The body will be executed for each node that has - * a kmem_cache_node structure allocated (which is true for all online nodes) - */ -#define for_each_kmem_cache_node(__s, __node, __n) \ - for (__node = 0; __node < nr_node_ids; __node++) \ - if ((__n = get_node(__s, __node))) - -#endif - -#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG) -void dump_unreclaimable_slab(void); -#else static inline void dump_unreclaimable_slab(void) { } -#endif void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr); -#ifdef CONFIG_SLAB_FREELIST_RANDOM -int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, - gfp_t gfp); -void cache_random_seq_destroy(struct kmem_cache *cachep); -#else static inline int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, gfp_t gfp) { return 0; } static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { } -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c) { @@ -871,11 +453,7 @@ static inline bool slab_want_init_on_free(struct kmem_cache *c) return false; } -#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) -void debugfs_slab_release(struct kmem_cache *); -#else static inline void debugfs_slab_release(struct kmem_cache *s) { } -#endif #ifdef CONFIG_PRINTK #define KS_ADDRS_COUNT 16 @@ -903,8 +481,4 @@ void __check_heap_object(const void *ptr, unsigned long n, } #endif -#ifdef CONFIG_SLUB_DEBUG -void skip_orig_size_check(struct kmem_cache *s, const void *object); -#endif - #endif /* MM_SLAB_H */ diff --git a/mm/slab_common.c b/mm/slab_common.c index bf4e777cfe90..5f6a59e31abd 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -69,11 +69,6 @@ static int __init setup_slab_merge(char *str) return 1; } -#ifdef CONFIG_SLUB -__setup_param("slub_nomerge", slub_nomerge, setup_slab_nomerge, 0); -__setup_param("slub_merge", slub_merge, setup_slab_merge, 0); -#endif - __setup("slab_nomerge", setup_slab_nomerge); __setup("slab_merge", setup_slab_merge); @@ -195,15 +190,29 @@ struct kmem_cache *find_mergeable(unsigned int size, unsigned int align, if (s->size - size >= sizeof(void *)) continue; - if (IS_ENABLED(CONFIG_SLAB) && align && - (align > s->align || s->align % align)) - continue; - return s; } return NULL; } +struct slab_rcu { + struct rcu_head head; + int size; +}; + +int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags) +{ + if (flags & SLAB_TYPESAFE_BY_RCU) { + /* leave room for rcu footer at the end of object */ + c->size += sizeof(struct slab_rcu); + } + + /* Actual size allocated */ + c->size = PAGE_SIZE << get_order(c->size); + c->flags = flags; + return 0; +} + static struct kmem_cache *create_cache(const char *name, unsigned int object_size, unsigned int align, slab_flags_t flags, unsigned int useroffset, @@ -285,20 +294,6 @@ kmem_cache_create_usercopy(const char *name, const char *cache_name; int err; -#ifdef CONFIG_SLUB_DEBUG - /* - * If no slub_debug was enabled globally, the static key is not yet - * enabled by setup_slub_debug(). Enable it if the cache is being - * created with any of the debugging flags passed explicitly. - * It's also possible that this is the first cache created with - * SLAB_STORE_USER and we should init stack_depot for it. - */ - if (flags & SLAB_DEBUG_FLAGS) - static_branch_enable(&slub_debug_enabled); - if (flags & SLAB_STORE_USER) - stack_depot_init(); -#endif - mutex_lock(&slab_mutex); err = kmem_cache_sanity_check(name, size); @@ -552,7 +547,8 @@ static void kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab * { if (__kfence_obj_info(kpp, object, slab)) return; - __kmem_obj_info(kpp, object, slab); + kpp->kp_ptr = object; + kpp->kp_slab = slab; } /** @@ -625,462 +621,6 @@ void kmem_dump_obj(void *object) EXPORT_SYMBOL_GPL(kmem_dump_obj); #endif -#ifndef CONFIG_SLOB -/* Create a cache during boot when no slab services are available yet */ -void __init create_boot_cache(struct kmem_cache *s, const char *name, - unsigned int size, slab_flags_t flags, - unsigned int useroffset, unsigned int usersize) -{ - int err; - unsigned int align = ARCH_KMALLOC_MINALIGN; - - s->name = name; - s->size = s->object_size = size; - - /* - * For power of two sizes, guarantee natural alignment for kmalloc - * caches, regardless of SL*B debugging options. - */ - if (is_power_of_2(size)) - align = max(align, size); - s->align = calculate_alignment(flags, align, size); - -#ifdef CONFIG_HARDENED_USERCOPY - s->useroffset = useroffset; - s->usersize = usersize; -#endif - - err = __kmem_cache_create(s, flags); - - if (err) - panic("Creation of kmalloc slab %s size=%u failed. Reason %d\n", - name, size, err); - - s->refcount = -1; /* Exempt from merging for now */ -} - -struct kmem_cache *__init create_kmalloc_cache(const char *name, - unsigned int size, slab_flags_t flags, - unsigned int useroffset, unsigned int usersize) -{ - struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); - - if (!s) - panic("Out of memory when creating slab %s\n", name); - - create_boot_cache(s, name, size, flags | SLAB_KMALLOC, useroffset, - usersize); - list_add(&s->list, &slab_caches); - s->refcount = 1; - return s; -} - -struct kmem_cache * -kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1] __ro_after_init = -{ /* initialization for https://bugs.llvm.org/show_bug.cgi?id=42570 */ }; -EXPORT_SYMBOL(kmalloc_caches); - -/* - * Conversion table for small slabs sizes / 8 to the index in the - * kmalloc array. This is necessary for slabs < 192 since we have non power - * of two cache sizes there. The size of larger slabs can be determined using - * fls. - */ -static u8 size_index[24] __ro_after_init = { - 3, /* 8 */ - 4, /* 16 */ - 5, /* 24 */ - 5, /* 32 */ - 6, /* 40 */ - 6, /* 48 */ - 6, /* 56 */ - 6, /* 64 */ - 1, /* 72 */ - 1, /* 80 */ - 1, /* 88 */ - 1, /* 96 */ - 7, /* 104 */ - 7, /* 112 */ - 7, /* 120 */ - 7, /* 128 */ - 2, /* 136 */ - 2, /* 144 */ - 2, /* 152 */ - 2, /* 160 */ - 2, /* 168 */ - 2, /* 176 */ - 2, /* 184 */ - 2 /* 192 */ -}; - -static inline unsigned int size_index_elem(unsigned int bytes) -{ - return (bytes - 1) / 8; -} - -/* - * Find the kmem_cache structure that serves a given size of - * allocation - */ -struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags) -{ - unsigned int index; - - if (size <= 192) { - if (!size) - return ZERO_SIZE_PTR; - - index = size_index[size_index_elem(size)]; - } else { - if (WARN_ON_ONCE(size > KMALLOC_MAX_CACHE_SIZE)) - return NULL; - index = fls(size - 1); - } - - return kmalloc_caches[kmalloc_type(flags)][index]; -} - -size_t kmalloc_size_roundup(size_t size) -{ - struct kmem_cache *c; - - /* Short-circuit the 0 size case. */ - if (unlikely(size == 0)) - return 0; - /* Short-circuit saturated "too-large" case. */ - if (unlikely(size == SIZE_MAX)) - return SIZE_MAX; - /* Above the smaller buckets, size is a multiple of page size. */ - if (size > KMALLOC_MAX_CACHE_SIZE) - return PAGE_SIZE << get_order(size); - - /* The flags don't matter since size_index is common to all. */ - c = kmalloc_slab(size, GFP_KERNEL); - return c ? c->object_size : 0; -} -EXPORT_SYMBOL(kmalloc_size_roundup); - -#ifdef CONFIG_ZONE_DMA -#define KMALLOC_DMA_NAME(sz) .name[KMALLOC_DMA] = "dma-kmalloc-" #sz, -#else -#define KMALLOC_DMA_NAME(sz) -#endif - -#ifdef CONFIG_MEMCG_KMEM -#define KMALLOC_CGROUP_NAME(sz) .name[KMALLOC_CGROUP] = "kmalloc-cg-" #sz, -#else -#define KMALLOC_CGROUP_NAME(sz) -#endif - -#ifndef CONFIG_SLUB_TINY -#define KMALLOC_RCL_NAME(sz) .name[KMALLOC_RECLAIM] = "kmalloc-rcl-" #sz, -#else -#define KMALLOC_RCL_NAME(sz) -#endif - -#define INIT_KMALLOC_INFO(__size, __short_size) \ -{ \ - .name[KMALLOC_NORMAL] = "kmalloc-" #__short_size, \ - KMALLOC_RCL_NAME(__short_size) \ - KMALLOC_CGROUP_NAME(__short_size) \ - KMALLOC_DMA_NAME(__short_size) \ - .size = __size, \ -} - -/* - * kmalloc_info[] is to make slub_debug=,kmalloc-xx option work at boot time. - * kmalloc_index() supports up to 2^21=2MB, so the final entry of the table is - * kmalloc-2M. - */ -const struct kmalloc_info_struct kmalloc_info[] __initconst = { - INIT_KMALLOC_INFO(0, 0), - INIT_KMALLOC_INFO(96, 96), - INIT_KMALLOC_INFO(192, 192), - INIT_KMALLOC_INFO(8, 8), - INIT_KMALLOC_INFO(16, 16), - INIT_KMALLOC_INFO(32, 32), - INIT_KMALLOC_INFO(64, 64), - INIT_KMALLOC_INFO(128, 128), - INIT_KMALLOC_INFO(256, 256), - INIT_KMALLOC_INFO(512, 512), - INIT_KMALLOC_INFO(1024, 1k), - INIT_KMALLOC_INFO(2048, 2k), - INIT_KMALLOC_INFO(4096, 4k), - INIT_KMALLOC_INFO(8192, 8k), - INIT_KMALLOC_INFO(16384, 16k), - INIT_KMALLOC_INFO(32768, 32k), - INIT_KMALLOC_INFO(65536, 64k), - INIT_KMALLOC_INFO(131072, 128k), - INIT_KMALLOC_INFO(262144, 256k), - INIT_KMALLOC_INFO(524288, 512k), - INIT_KMALLOC_INFO(1048576, 1M), - INIT_KMALLOC_INFO(2097152, 2M) -}; - -/* - * Patch up the size_index table if we have strange large alignment - * requirements for the kmalloc array. This is only the case for - * MIPS it seems. The standard arches will not generate any code here. - * - * Largest permitted alignment is 256 bytes due to the way we - * handle the index determination for the smaller caches. - * - * Make sure that nothing crazy happens if someone starts tinkering - * around with ARCH_KMALLOC_MINALIGN - */ -void __init setup_kmalloc_cache_index_table(void) -{ - unsigned int i; - - BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 || - !is_power_of_2(KMALLOC_MIN_SIZE)); - - for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) { - unsigned int elem = size_index_elem(i); - - if (elem >= ARRAY_SIZE(size_index)) - break; - size_index[elem] = KMALLOC_SHIFT_LOW; - } - - if (KMALLOC_MIN_SIZE >= 64) { - /* - * The 96 byte sized cache is not used if the alignment - * is 64 byte. - */ - for (i = 64 + 8; i <= 96; i += 8) - size_index[size_index_elem(i)] = 7; - - } - - if (KMALLOC_MIN_SIZE >= 128) { - /* - * The 192 byte sized cache is not used if the alignment - * is 128 byte. Redirect kmalloc to use the 256 byte cache - * instead. - */ - for (i = 128 + 8; i <= 192; i += 8) - size_index[size_index_elem(i)] = 8; - } -} - -static void __init -new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags) -{ - if ((KMALLOC_RECLAIM != KMALLOC_NORMAL) && (type == KMALLOC_RECLAIM)) { - flags |= SLAB_RECLAIM_ACCOUNT; - } else if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_CGROUP)) { - if (mem_cgroup_kmem_disabled()) { - kmalloc_caches[type][idx] = kmalloc_caches[KMALLOC_NORMAL][idx]; - return; - } - flags |= SLAB_ACCOUNT; - } else if (IS_ENABLED(CONFIG_ZONE_DMA) && (type == KMALLOC_DMA)) { - flags |= SLAB_CACHE_DMA; - } - - kmalloc_caches[type][idx] = create_kmalloc_cache( - kmalloc_info[idx].name[type], - kmalloc_info[idx].size, flags, 0, - kmalloc_info[idx].size); - - /* - * If CONFIG_MEMCG_KMEM is enabled, disable cache merging for - * KMALLOC_NORMAL caches. - */ - if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_NORMAL)) - kmalloc_caches[type][idx]->refcount = -1; -} - -/* - * Create the kmalloc array. Some of the regular kmalloc arrays - * may already have been created because they were needed to - * enable allocations for slab creation. - */ -void __init create_kmalloc_caches(slab_flags_t flags) -{ - int i; - enum kmalloc_cache_type type; - - /* - * Including KMALLOC_CGROUP if CONFIG_MEMCG_KMEM defined - */ - for (type = KMALLOC_NORMAL; type < NR_KMALLOC_TYPES; type++) { - for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) { - if (!kmalloc_caches[type][i]) - new_kmalloc_cache(i, type, flags); - - /* - * Caches that are not of the two-to-the-power-of size. - * These have to be created immediately after the - * earlier power of two caches - */ - if (KMALLOC_MIN_SIZE <= 32 && i == 6 && - !kmalloc_caches[type][1]) - new_kmalloc_cache(1, type, flags); - if (KMALLOC_MIN_SIZE <= 64 && i == 7 && - !kmalloc_caches[type][2]) - new_kmalloc_cache(2, type, flags); - } - } - - /* Kmalloc array is now usable */ - slab_state = UP; -} - -void free_large_kmalloc(struct folio *folio, void *object) -{ - unsigned int order = folio_order(folio); - - if (WARN_ON_ONCE(order == 0)) - pr_warn_once("object pointer: 0x%p\n", object); - - kmemleak_free(object); - kasan_kfree_large(object); - kmsan_kfree_large(object); - - mod_lruvec_page_state(folio_page(folio, 0), NR_SLAB_UNRECLAIMABLE_B, - -(PAGE_SIZE << order)); - __free_pages(folio_page(folio, 0), order); -} - -static void *__kmalloc_large_node(size_t size, gfp_t flags, int node); -static __always_inline -void *__do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller) -{ - struct kmem_cache *s; - void *ret; - - if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) { - ret = __kmalloc_large_node(size, flags, node); - trace_kmalloc(caller, ret, size, - PAGE_SIZE << get_order(size), flags, node); - return ret; - } - - s = kmalloc_slab(size, flags); - - if (unlikely(ZERO_OR_NULL_PTR(s))) - return s; - - ret = __kmem_cache_alloc_node(s, flags, node, size, caller); - ret = kasan_kmalloc(s, ret, size, flags); - trace_kmalloc(caller, ret, size, s->size, flags, node); - return ret; -} - -void *__kmalloc_node(size_t size, gfp_t flags, int node) -{ - return __do_kmalloc_node(size, flags, node, _RET_IP_); -} -EXPORT_SYMBOL(__kmalloc_node); - -void *__kmalloc(size_t size, gfp_t flags) -{ - return __do_kmalloc_node(size, flags, NUMA_NO_NODE, _RET_IP_); -} -EXPORT_SYMBOL(__kmalloc); - -void *__kmalloc_node_track_caller(size_t size, gfp_t flags, - int node, unsigned long caller) -{ - return __do_kmalloc_node(size, flags, node, caller); -} -EXPORT_SYMBOL(__kmalloc_node_track_caller); - -/** - * kfree - free previously allocated memory - * @object: pointer returned by kmalloc. - * - * If @object is NULL, no operation is performed. - * - * Don't free memory not originally allocated by kmalloc() - * or you will run into trouble. - */ -void kfree(const void *object) -{ - struct folio *folio; - struct slab *slab; - struct kmem_cache *s; - - trace_kfree(_RET_IP_, object); - - if (unlikely(ZERO_OR_NULL_PTR(object))) - return; - - folio = virt_to_folio(object); - if (unlikely(!folio_test_slab(folio))) { - free_large_kmalloc(folio, (void *)object); - return; - } - - slab = folio_slab(folio); - s = slab->slab_cache; - __kmem_cache_free(s, (void *)object, _RET_IP_); -} -EXPORT_SYMBOL(kfree); - -/** - * __ksize -- Report full size of underlying allocation - * @object: pointer to the object - * - * This should only be used internally to query the true size of allocations. - * It is not meant to be a way to discover the usable size of an allocation - * after the fact. Instead, use kmalloc_size_roundup(). Using memory beyond - * the originally requested allocation size may trigger KASAN, UBSAN_BOUNDS, - * and/or FORTIFY_SOURCE. - * - * Return: size of the actual memory used by @object in bytes - */ -size_t __ksize(const void *object) -{ - struct folio *folio; - - if (unlikely(object == ZERO_SIZE_PTR)) - return 0; - - folio = virt_to_folio(object); - - if (unlikely(!folio_test_slab(folio))) { - if (WARN_ON(folio_size(folio) <= KMALLOC_MAX_CACHE_SIZE)) - return 0; - if (WARN_ON(object != folio_address(folio))) - return 0; - return folio_size(folio); - } - -#ifdef CONFIG_SLUB_DEBUG - skip_orig_size_check(folio_slab(folio)->slab_cache, object); -#endif - - return slab_ksize(folio_slab(folio)->slab_cache); -} - -void *kmalloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size) -{ - void *ret = __kmem_cache_alloc_node(s, gfpflags, NUMA_NO_NODE, - size, _RET_IP_); - - trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags, NUMA_NO_NODE); - - ret = kasan_kmalloc(s, ret, size, gfpflags); - return ret; -} -EXPORT_SYMBOL(kmalloc_trace); - -void *kmalloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, - int node, size_t size) -{ - void *ret = __kmem_cache_alloc_node(s, gfpflags, node, size, _RET_IP_); - - trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags, node); - - ret = kasan_kmalloc(s, ret, size, gfpflags); - return ret; -} -EXPORT_SYMBOL(kmalloc_node_trace); -#endif /* !CONFIG_SLOB */ - gfp_t kmalloc_fix_flags(gfp_t flags) { gfp_t invalid_mask = flags & GFP_SLAB_BUG_MASK; @@ -1144,202 +684,44 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) } EXPORT_SYMBOL(kmalloc_large_node); -#ifdef CONFIG_SLAB_FREELIST_RANDOM -/* Randomize a generic freelist */ -static void freelist_randomize(struct rnd_state *state, unsigned int *list, - unsigned int count) -{ - unsigned int rand; - unsigned int i; - - for (i = 0; i < count; i++) - list[i] = i; - - /* Fisher-Yates shuffle */ - for (i = count - 1; i > 0; i--) { - rand = prandom_u32_state(state); - rand %= (i + 1); - swap(list[i], list[rand]); - } -} - -/* Create a random sequence per cache */ -int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, - gfp_t gfp) -{ - struct rnd_state state; - - if (count < 2 || cachep->random_seq) - return 0; - - cachep->random_seq = kcalloc(count, sizeof(unsigned int), gfp); - if (!cachep->random_seq) - return -ENOMEM; - - /* Get best entropy at this stage of boot */ - prandom_seed_state(&state, get_random_long()); - - freelist_randomize(&state, cachep->random_seq, count); - return 0; -} - -/* Destroy the per-cache random freelist sequence */ -void cache_random_seq_destroy(struct kmem_cache *cachep) -{ - kfree(cachep->random_seq); - cachep->random_seq = NULL; -} -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ - -#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG) -#ifdef CONFIG_SLAB -#define SLABINFO_RIGHTS (0600) -#else -#define SLABINFO_RIGHTS (0400) -#endif - -static void print_slabinfo_header(struct seq_file *m) -{ - /* - * Output format version, so at least we can change it - * without _too_ many complaints. - */ -#ifdef CONFIG_DEBUG_SLAB - seq_puts(m, "slabinfo - version: 2.1 (statistics)\n"); -#else - seq_puts(m, "slabinfo - version: 2.1\n"); -#endif - seq_puts(m, "# name <active_objs> <num_objs> <objsize> <objperslab> <pagesperslab>"); - seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>"); - seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>"); -#ifdef CONFIG_DEBUG_SLAB - seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> <error> <maxfreeable> <nodeallocs> <remotefrees> <alienoverflow>"); - seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>"); -#endif - seq_putc(m, '\n'); -} - -static void *slab_start(struct seq_file *m, loff_t *pos) -{ - mutex_lock(&slab_mutex); - return seq_list_start(&slab_caches, *pos); -} - -static void *slab_next(struct seq_file *m, void *p, loff_t *pos) -{ - return seq_list_next(p, &slab_caches, pos); -} - -static void slab_stop(struct seq_file *m, void *p) -{ - mutex_unlock(&slab_mutex); -} - -static void cache_show(struct kmem_cache *s, struct seq_file *m) +static __always_inline void * +__do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) { - struct slabinfo sinfo; + void *ret; - memset(&sinfo, 0, sizeof(sinfo)); - get_slabinfo(s, &sinfo); + gfp &= gfp_allowed_mask; - seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", - s->name, sinfo.active_objs, sinfo.num_objs, s->size, - sinfo.objects_per_slab, (1 << sinfo.cache_order)); + might_alloc(gfp); - seq_printf(m, " : tunables %4u %4u %4u", - sinfo.limit, sinfo.batchcount, sinfo.shared); - seq_printf(m, " : slabdata %6lu %6lu %6lu", - sinfo.active_slabs, sinfo.num_slabs, sinfo.shared_avail); - slabinfo_show_stats(m, s); - seq_putc(m, '\n'); -} + if (unlikely(!size)) + ret = ZERO_SIZE_PTR; + else + ret = __kmalloc_large_node(size, gfp, node); -static int slab_show(struct seq_file *m, void *p) -{ - struct kmem_cache *s = list_entry(p, struct kmem_cache, list); + trace_kmalloc(caller, ret, size, PAGE_SIZE << get_order(size), gfp, node); - if (p == slab_caches.next) - print_slabinfo_header(m); - cache_show(s, m); - return 0; + kmemleak_alloc(ret, size, 1, gfp); + return ret; } -void dump_unreclaimable_slab(void) +void *__kmalloc(size_t size, gfp_t gfp) { - struct kmem_cache *s; - struct slabinfo sinfo; - - /* - * Here acquiring slab_mutex is risky since we don't prefer to get - * sleep in oom path. But, without mutex hold, it may introduce a - * risk of crash. - * Use mutex_trylock to protect the list traverse, dump nothing - * without acquiring the mutex. - */ - if (!mutex_trylock(&slab_mutex)) { - pr_warn("excessive unreclaimable slab but cannot dump stats\n"); - return; - } - - pr_info("Unreclaimable slab info:\n"); - pr_info("Name Used Total\n"); - - list_for_each_entry(s, &slab_caches, list) { - if (s->flags & SLAB_RECLAIM_ACCOUNT) - continue; - - get_slabinfo(s, &sinfo); - - if (sinfo.num_objs > 0) - pr_info("%-17s %10luKB %10luKB\n", s->name, - (sinfo.active_objs * s->size) / 1024, - (sinfo.num_objs * s->size) / 1024); - } - mutex_unlock(&slab_mutex); + return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_); } +EXPORT_SYMBOL(__kmalloc); -/* - * slabinfo_op - iterator that generates /proc/slabinfo - * - * Output layout: - * cache-name - * num-active-objs - * total-objs - * object size - * num-active-slabs - * total-slabs - * num-pages-per-slab - * + further values on SMP and with statistics enabled - */ -static const struct seq_operations slabinfo_op = { - .start = slab_start, - .next = slab_next, - .stop = slab_stop, - .show = slab_show, -}; - -static int slabinfo_open(struct inode *inode, struct file *file) +void *__kmalloc_node(size_t size, gfp_t gfp, int node) { - return seq_open(file, &slabinfo_op); + return __do_kmalloc_node(size, gfp, node, _RET_IP_); } +EXPORT_SYMBOL(__kmalloc_node); -static const struct proc_ops slabinfo_proc_ops = { - .proc_flags = PROC_ENTRY_PERMANENT, - .proc_open = slabinfo_open, - .proc_read = seq_read, - .proc_write = slabinfo_write, - .proc_lseek = seq_lseek, - .proc_release = seq_release, -}; - -static int __init slab_proc_init(void) +void *__kmalloc_node_track_caller(size_t size, gfp_t gfp, + int node, unsigned long caller) { - proc_create("slabinfo", SLABINFO_RIGHTS, NULL, &slabinfo_proc_ops); - return 0; + return __do_kmalloc_node(size, gfp, node, caller); } -module_init(slab_proc_init); - -#endif /* CONFIG_SLAB || CONFIG_SLUB_DEBUG */ +EXPORT_SYMBOL(__kmalloc_node_track_caller); static __always_inline __realloc_size(2) void * __do_krealloc(const void *p, size_t new_size, gfp_t flags) @@ -1402,6 +784,27 @@ void *krealloc(const void *p, size_t new_size, gfp_t flags) } EXPORT_SYMBOL(krealloc); +void kfree(const void *block) +{ + struct folio *sp; + unsigned int order; + + trace_kfree(_RET_IP_, block); + + if (unlikely(ZERO_OR_NULL_PTR(block))) + return; + kmemleak_free(block); + + sp = virt_to_folio(block); + BUG_ON(folio_test_slab(sp)); + order = folio_order(sp); + + mod_node_page_state(folio_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, + -(PAGE_SIZE << order)); + __free_pages(folio_page(sp, 0), order); +} +EXPORT_SYMBOL(kfree); + /** * kfree_sensitive - Clear sensitive information in memory before freeing * @p: object to free memory of @@ -1427,6 +830,34 @@ void kfree_sensitive(const void *p) } EXPORT_SYMBOL(kfree_sensitive); +size_t kmalloc_size_roundup(size_t size) +{ + /* Short-circuit the 0 size case. */ + if (unlikely(size == 0)) + return 0; + /* Short-circuit saturated "too-large" case. */ + if (unlikely(size == SIZE_MAX)) + return SIZE_MAX; + + return PAGE_SIZE << get_order(size); +} + +EXPORT_SYMBOL(kmalloc_size_roundup); + +/* can't use ksize for kmem_cache_alloc memory, only kmalloc */ +size_t __ksize(const void *block) +{ + struct folio *folio; + + BUG_ON(!block); + if (unlikely(block == ZERO_SIZE_PTR)) + return 0; + + folio = virt_to_folio(block); + BUG_ON(folio_test_slab(folio)); + return folio_size(folio); +} + size_t ksize(const void *objp) { /* @@ -1451,6 +882,131 @@ size_t ksize(const void *objp) } EXPORT_SYMBOL(ksize); +static void *__kmem_cache_alloc_node(struct kmem_cache *c, gfp_t flags, int node) +{ + void *b; + + flags &= gfp_allowed_mask; + + might_alloc(flags); + + b = __kmalloc_large_node(c->size, flags, node); + trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); + + if (b && c->ctor) { + WARN_ON_ONCE(flags & __GFP_ZERO); + c->ctor(b); + } + + kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); + return b; +} + +void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) +{ + return __kmem_cache_alloc_node(cachep, flags, NUMA_NO_NODE); +} +EXPORT_SYMBOL(kmem_cache_alloc); + + +void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags) +{ + return __kmem_cache_alloc_node(cachep, flags, NUMA_NO_NODE); +} +EXPORT_SYMBOL(kmem_cache_alloc_lru); + +void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node) +{ + return __kmem_cache_alloc_node(cachep, gfp, node); +} +EXPORT_SYMBOL(kmem_cache_alloc_node); + +static void kmem_rcu_free(struct rcu_head *head) +{ + struct slab_rcu *slab_rcu = (struct slab_rcu *)head; + void *b = (void *)slab_rcu - (slab_rcu->size - sizeof(struct slab_rcu)); + + kfree(b); +} + +void kmem_cache_free(struct kmem_cache *c, void *b) +{ + kmemleak_free_recursive(b, c->flags); + trace_kmem_cache_free(_RET_IP_, b, c); + if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) { + struct slab_rcu *slab_rcu; + slab_rcu = b + (c->size - sizeof(struct slab_rcu)); + slab_rcu->size = c->size; + call_rcu(&slab_rcu->head, kmem_rcu_free); + } else { + kfree(b); + } +} +EXPORT_SYMBOL(kmem_cache_free); + +void kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p) +{ + size_t i; + + for (i = 0; i < nr; i++) { + if (s) + kmem_cache_free(s, p[i]); + else + kfree(p[i]); + } +} +EXPORT_SYMBOL(kmem_cache_free_bulk); + +int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr, + void **p) +{ + size_t i; + + for (i = 0; i < nr; i++) { + void *x = p[i] = kmem_cache_alloc(s, flags); + + if (!x) { + kmem_cache_free_bulk(s, i, p); + return 0; + } + } + return i; +} +EXPORT_SYMBOL(kmem_cache_alloc_bulk); + +int __kmem_cache_shutdown(struct kmem_cache *c) +{ + /* No way to check for remaining objects */ + return 0; +} + +void __kmem_cache_release(struct kmem_cache *c) +{ +} + +int __kmem_cache_shrink(struct kmem_cache *d) +{ + return 0; +} + +static struct kmem_cache kmem_cache_boot = { + .name = "kmem_cache", + .size = sizeof(struct kmem_cache), + .flags = SLAB_PANIC, + .align = ARCH_KMALLOC_MINALIGN, +}; + +void __init kmem_cache_init(void) +{ + kmem_cache = &kmem_cache_boot; + slab_state = UP; +} + +void __init kmem_cache_init_late(void) +{ + slab_state = FULL; +} + /* Tracepoints definitions. */ EXPORT_TRACEPOINT_SYMBOL(kmalloc); EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc); diff --git a/mm/slob.c b/mm/slob.c deleted file mode 100644 index fe567fcfa3a3..000000000000 --- a/mm/slob.c +++ /dev/null @@ -1,757 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * SLOB Allocator: Simple List Of Blocks - * - * Matt Mackall <mpm@selenic.com> 12/30/03 - * - * NUMA support by Paul Mundt, 2007. - * - * How SLOB works: - * - * The core of SLOB is a traditional K&R style heap allocator, with - * support for returning aligned objects. The granularity of this - * allocator is as little as 2 bytes, however typically most architectures - * will require 4 bytes on 32-bit and 8 bytes on 64-bit. - * - * The slob heap is a set of linked list of pages from alloc_pages(), - * and within each page, there is a singly-linked list of free blocks - * (slob_t). The heap is grown on demand. To reduce fragmentation, - * heap pages are segregated into three lists, with objects less than - * 256 bytes, objects less than 1024 bytes, and all other objects. - * - * Allocation from heap involves first searching for a page with - * sufficient free blocks (using a next-fit-like approach) followed by - * a first-fit scan of the page. Deallocation inserts objects back - * into the free list in address order, so this is effectively an - * address-ordered first fit. - * - * Above this is an implementation of kmalloc/kfree. Blocks returned - * from kmalloc are prepended with a 4-byte header with the kmalloc size. - * If kmalloc is asked for objects of PAGE_SIZE or larger, it calls - * alloc_pages() directly, allocating compound pages so the page order - * does not have to be separately tracked. - * These objects are detected in kfree() because folio_test_slab() - * is false for them. - * - * SLAB is emulated on top of SLOB by simply calling constructors and - * destructors for every SLAB allocation. Objects are returned with the - * 4-byte alignment unless the SLAB_HWCACHE_ALIGN flag is set, in which - * case the low-level allocator will fragment blocks to create the proper - * alignment. Again, objects of page-size or greater are allocated by - * calling alloc_pages(). As SLAB objects know their size, no separate - * size bookkeeping is necessary and there is essentially no allocation - * space overhead, and compound pages aren't needed for multi-page - * allocations. - * - * NUMA support in SLOB is fairly simplistic, pushing most of the real - * logic down to the page allocator, and simply doing the node accounting - * on the upper levels. In the event that a node id is explicitly - * provided, __alloc_pages_node() with the specified node id is used - * instead. The common case (or when the node id isn't explicitly provided) - * will default to the current node, as per numa_node_id(). - * - * Node aware pages are still inserted in to the global freelist, and - * these are scanned for by matching against the node id encoded in the - * page flags. As a result, block allocations that can be satisfied from - * the freelist will only be done so on pages residing on the same node, - * in order to prevent random node placement. - */ - -#include <linux/kernel.h> -#include <linux/slab.h> - -#include <linux/mm.h> -#include <linux/swap.h> /* struct reclaim_state */ -#include <linux/cache.h> -#include <linux/init.h> -#include <linux/export.h> -#include <linux/rcupdate.h> -#include <linux/list.h> -#include <linux/kmemleak.h> - -#include <trace/events/kmem.h> - -#include <linux/atomic.h> - -#include "slab.h" -/* - * slob_block has a field 'units', which indicates size of block if +ve, - * or offset of next block if -ve (in SLOB_UNITs). - * - * Free blocks of size 1 unit simply contain the offset of the next block. - * Those with larger size contain their size in the first SLOB_UNIT of - * memory, and the offset of the next free block in the second SLOB_UNIT. - */ -#if PAGE_SIZE <= (32767 * 2) -typedef s16 slobidx_t; -#else -typedef s32 slobidx_t; -#endif - -struct slob_block { - slobidx_t units; -}; -typedef struct slob_block slob_t; - -/* - * All partially free slob pages go on these lists. - */ -#define SLOB_BREAK1 256 -#define SLOB_BREAK2 1024 -static LIST_HEAD(free_slob_small); -static LIST_HEAD(free_slob_medium); -static LIST_HEAD(free_slob_large); - -/* - * slob_page_free: true for pages on free_slob_pages list. - */ -static inline int slob_page_free(struct slab *slab) -{ - return PageSlobFree(slab_page(slab)); -} - -static void set_slob_page_free(struct slab *slab, struct list_head *list) -{ - list_add(&slab->slab_list, list); - __SetPageSlobFree(slab_page(slab)); -} - -static inline void clear_slob_page_free(struct slab *slab) -{ - list_del(&slab->slab_list); - __ClearPageSlobFree(slab_page(slab)); -} - -#define SLOB_UNIT sizeof(slob_t) -#define SLOB_UNITS(size) DIV_ROUND_UP(size, SLOB_UNIT) - -/* - * struct slob_rcu is inserted at the tail of allocated slob blocks, which - * were created with a SLAB_TYPESAFE_BY_RCU slab. slob_rcu is used to free - * the block using call_rcu. - */ -struct slob_rcu { - struct rcu_head head; - int size; -}; - -/* - * slob_lock protects all slob allocator structures. - */ -static DEFINE_SPINLOCK(slob_lock); - -/* - * Encode the given size and next info into a free slob block s. - */ -static void set_slob(slob_t *s, slobidx_t size, slob_t *next) -{ - slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); - slobidx_t offset = next - base; - - if (size > 1) { - s[0].units = size; - s[1].units = offset; - } else - s[0].units = -offset; -} - -/* - * Return the size of a slob block. - */ -static slobidx_t slob_units(slob_t *s) -{ - if (s->units > 0) - return s->units; - return 1; -} - -/* - * Return the next free slob block pointer after this one. - */ -static slob_t *slob_next(slob_t *s) -{ - slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); - slobidx_t next; - - if (s[0].units < 0) - next = -s[0].units; - else - next = s[1].units; - return base+next; -} - -/* - * Returns true if s is the last free block in its page. - */ -static int slob_last(slob_t *s) -{ - return !((unsigned long)slob_next(s) & ~PAGE_MASK); -} - -static void *slob_new_pages(gfp_t gfp, int order, int node) -{ - struct page *page; - -#ifdef CONFIG_NUMA - if (node != NUMA_NO_NODE) - page = __alloc_pages_node(node, gfp, order); - else -#endif - page = alloc_pages(gfp, order); - - if (!page) - return NULL; - - mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE_B, - PAGE_SIZE << order); - return page_address(page); -} - -static void slob_free_pages(void *b, int order) -{ - struct page *sp = virt_to_page(b); - - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += 1 << order; - - mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, - -(PAGE_SIZE << order)); - __free_pages(sp, order); -} - -/* - * slob_page_alloc() - Allocate a slob block within a given slob_page sp. - * @sp: Page to look in. - * @size: Size of the allocation. - * @align: Allocation alignment. - * @align_offset: Offset in the allocated block that will be aligned. - * @page_removed_from_list: Return parameter. - * - * Tries to find a chunk of memory at least @size bytes big within @page. - * - * Return: Pointer to memory if allocated, %NULL otherwise. If the - * allocation fills up @page then the page is removed from the - * freelist, in this case @page_removed_from_list will be set to - * true (set to false otherwise). - */ -static void *slob_page_alloc(struct slab *sp, size_t size, int align, - int align_offset, bool *page_removed_from_list) -{ - slob_t *prev, *cur, *aligned = NULL; - int delta = 0, units = SLOB_UNITS(size); - - *page_removed_from_list = false; - for (prev = NULL, cur = sp->freelist; ; prev = cur, cur = slob_next(cur)) { - slobidx_t avail = slob_units(cur); - - /* - * 'aligned' will hold the address of the slob block so that the - * address 'aligned'+'align_offset' is aligned according to the - * 'align' parameter. This is for kmalloc() which prepends the - * allocated block with its size, so that the block itself is - * aligned when needed. - */ - if (align) { - aligned = (slob_t *) - (ALIGN((unsigned long)cur + align_offset, align) - - align_offset); - delta = aligned - cur; - } - if (avail >= units + delta) { /* room enough? */ - slob_t *next; - - if (delta) { /* need to fragment head to align? */ - next = slob_next(cur); - set_slob(aligned, avail - delta, next); - set_slob(cur, delta, aligned); - prev = cur; - cur = aligned; - avail = slob_units(cur); - } - - next = slob_next(cur); - if (avail == units) { /* exact fit? unlink. */ - if (prev) - set_slob(prev, slob_units(prev), next); - else - sp->freelist = next; - } else { /* fragment */ - if (prev) - set_slob(prev, slob_units(prev), cur + units); - else - sp->freelist = cur + units; - set_slob(cur + units, avail - units, next); - } - - sp->units -= units; - if (!sp->units) { - clear_slob_page_free(sp); - *page_removed_from_list = true; - } - return cur; - } - if (slob_last(cur)) - return NULL; - } -} - -/* - * slob_alloc: entry point into the slob allocator. - */ -static void *slob_alloc(size_t size, gfp_t gfp, int align, int node, - int align_offset) -{ - struct folio *folio; - struct slab *sp; - struct list_head *slob_list; - slob_t *b = NULL; - unsigned long flags; - bool _unused; - - if (size < SLOB_BREAK1) - slob_list = &free_slob_small; - else if (size < SLOB_BREAK2) - slob_list = &free_slob_medium; - else - slob_list = &free_slob_large; - - spin_lock_irqsave(&slob_lock, flags); - /* Iterate through each partially free page, try to find room */ - list_for_each_entry(sp, slob_list, slab_list) { - bool page_removed_from_list = false; -#ifdef CONFIG_NUMA - /* - * If there's a node specification, search for a partial - * page with a matching node id in the freelist. - */ - if (node != NUMA_NO_NODE && slab_nid(sp) != node) - continue; -#endif - /* Enough room on this page? */ - if (sp->units < SLOB_UNITS(size)) - continue; - - b = slob_page_alloc(sp, size, align, align_offset, &page_removed_from_list); - if (!b) - continue; - - /* - * If slob_page_alloc() removed sp from the list then we - * cannot call list functions on sp. If so allocation - * did not fragment the page anyway so optimisation is - * unnecessary. - */ - if (!page_removed_from_list) { - /* - * Improve fragment distribution and reduce our average - * search time by starting our next search here. (see - * Knuth vol 1, sec 2.5, pg 449) - */ - if (!list_is_first(&sp->slab_list, slob_list)) - list_rotate_to_front(&sp->slab_list, slob_list); - } - break; - } - spin_unlock_irqrestore(&slob_lock, flags); - - /* Not enough space: must allocate a new page */ - if (!b) { - b = slob_new_pages(gfp & ~__GFP_ZERO, 0, node); - if (!b) - return NULL; - folio = virt_to_folio(b); - __folio_set_slab(folio); - sp = folio_slab(folio); - - spin_lock_irqsave(&slob_lock, flags); - sp->units = SLOB_UNITS(PAGE_SIZE); - sp->freelist = b; - INIT_LIST_HEAD(&sp->slab_list); - set_slob(b, SLOB_UNITS(PAGE_SIZE), b + SLOB_UNITS(PAGE_SIZE)); - set_slob_page_free(sp, slob_list); - b = slob_page_alloc(sp, size, align, align_offset, &_unused); - BUG_ON(!b); - spin_unlock_irqrestore(&slob_lock, flags); - } - if (unlikely(gfp & __GFP_ZERO)) - memset(b, 0, size); - return b; -} - -/* - * slob_free: entry point into the slob allocator. - */ -static void slob_free(void *block, int size) -{ - struct slab *sp; - slob_t *prev, *next, *b = (slob_t *)block; - slobidx_t units; - unsigned long flags; - struct list_head *slob_list; - - if (unlikely(ZERO_OR_NULL_PTR(block))) - return; - BUG_ON(!size); - - sp = virt_to_slab(block); - units = SLOB_UNITS(size); - - spin_lock_irqsave(&slob_lock, flags); - - if (sp->units + units == SLOB_UNITS(PAGE_SIZE)) { - /* Go directly to page allocator. Do not pass slob allocator */ - if (slob_page_free(sp)) - clear_slob_page_free(sp); - spin_unlock_irqrestore(&slob_lock, flags); - __folio_clear_slab(slab_folio(sp)); - slob_free_pages(b, 0); - return; - } - - if (!slob_page_free(sp)) { - /* This slob page is about to become partially free. Easy! */ - sp->units = units; - sp->freelist = b; - set_slob(b, units, - (void *)((unsigned long)(b + - SLOB_UNITS(PAGE_SIZE)) & PAGE_MASK)); - if (size < SLOB_BREAK1) - slob_list = &free_slob_small; - else if (size < SLOB_BREAK2) - slob_list = &free_slob_medium; - else - slob_list = &free_slob_large; - set_slob_page_free(sp, slob_list); - goto out; - } - - /* - * Otherwise the page is already partially free, so find reinsertion - * point. - */ - sp->units += units; - - if (b < (slob_t *)sp->freelist) { - if (b + units == sp->freelist) { - units += slob_units(sp->freelist); - sp->freelist = slob_next(sp->freelist); - } - set_slob(b, units, sp->freelist); - sp->freelist = b; - } else { - prev = sp->freelist; - next = slob_next(prev); - while (b > next) { - prev = next; - next = slob_next(prev); - } - - if (!slob_last(prev) && b + units == next) { - units += slob_units(next); - set_slob(b, units, slob_next(next)); - } else - set_slob(b, units, next); - - if (prev + slob_units(prev) == b) { - units = slob_units(b) + slob_units(prev); - set_slob(prev, units, slob_next(b)); - } else - set_slob(prev, slob_units(prev), b); - } -out: - spin_unlock_irqrestore(&slob_lock, flags); -} - -#ifdef CONFIG_PRINTK -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) -{ - kpp->kp_ptr = object; - kpp->kp_slab = slab; -} -#endif - -/* - * End of slob allocator proper. Begin kmem_cache_alloc and kmalloc frontend. - */ - -static __always_inline void * -__do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) -{ - unsigned int *m; - unsigned int minalign; - void *ret; - - minalign = max_t(unsigned int, ARCH_KMALLOC_MINALIGN, - arch_slab_minalign()); - gfp &= gfp_allowed_mask; - - might_alloc(gfp); - - if (size < PAGE_SIZE - minalign) { - int align = minalign; - - /* - * For power of two sizes, guarantee natural alignment for - * kmalloc()'d objects. - */ - if (is_power_of_2(size)) - align = max_t(unsigned int, minalign, size); - - if (!size) - return ZERO_SIZE_PTR; - - m = slob_alloc(size + minalign, gfp, align, node, minalign); - - if (!m) - return NULL; - *m = size; - ret = (void *)m + minalign; - - trace_kmalloc(caller, ret, size, size + minalign, gfp, node); - } else { - unsigned int order = get_order(size); - - if (likely(order)) - gfp |= __GFP_COMP; - ret = slob_new_pages(gfp, order, node); - - trace_kmalloc(caller, ret, size, PAGE_SIZE << order, gfp, node); - } - - kmemleak_alloc(ret, size, 1, gfp); - return ret; -} - -void *__kmalloc(size_t size, gfp_t gfp) -{ - return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_); -} -EXPORT_SYMBOL(__kmalloc); - -void *__kmalloc_node_track_caller(size_t size, gfp_t gfp, - int node, unsigned long caller) -{ - return __do_kmalloc_node(size, gfp, node, caller); -} -EXPORT_SYMBOL(__kmalloc_node_track_caller); - -void kfree(const void *block) -{ - struct folio *sp; - - trace_kfree(_RET_IP_, block); - - if (unlikely(ZERO_OR_NULL_PTR(block))) - return; - kmemleak_free(block); - - sp = virt_to_folio(block); - if (folio_test_slab(sp)) { - unsigned int align = max_t(unsigned int, - ARCH_KMALLOC_MINALIGN, - arch_slab_minalign()); - unsigned int *m = (unsigned int *)(block - align); - - slob_free(m, *m + align); - } else { - unsigned int order = folio_order(sp); - - mod_node_page_state(folio_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, - -(PAGE_SIZE << order)); - __free_pages(folio_page(sp, 0), order); - - } -} -EXPORT_SYMBOL(kfree); - -size_t kmalloc_size_roundup(size_t size) -{ - /* Short-circuit the 0 size case. */ - if (unlikely(size == 0)) - return 0; - /* Short-circuit saturated "too-large" case. */ - if (unlikely(size == SIZE_MAX)) - return SIZE_MAX; - - return ALIGN(size, ARCH_KMALLOC_MINALIGN); -} - -EXPORT_SYMBOL(kmalloc_size_roundup); - -/* can't use ksize for kmem_cache_alloc memory, only kmalloc */ -size_t __ksize(const void *block) -{ - struct folio *folio; - unsigned int align; - unsigned int *m; - - BUG_ON(!block); - if (unlikely(block == ZERO_SIZE_PTR)) - return 0; - - folio = virt_to_folio(block); - if (unlikely(!folio_test_slab(folio))) - return folio_size(folio); - - align = max_t(unsigned int, ARCH_KMALLOC_MINALIGN, - arch_slab_minalign()); - m = (unsigned int *)(block - align); - return SLOB_UNITS(*m) * SLOB_UNIT; -} - -int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags) -{ - if (flags & SLAB_TYPESAFE_BY_RCU) { - /* leave room for rcu footer at the end of object */ - c->size += sizeof(struct slob_rcu); - } - - /* Actual size allocated */ - c->size = SLOB_UNITS(c->size) * SLOB_UNIT; - c->flags = flags; - return 0; -} - -static void *slob_alloc_node(struct kmem_cache *c, gfp_t flags, int node) -{ - void *b; - - flags &= gfp_allowed_mask; - - might_alloc(flags); - - if (c->size < PAGE_SIZE) { - b = slob_alloc(c->size, flags, c->align, node, 0); - trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); - } else { - b = slob_new_pages(flags, get_order(c->size), node); - trace_kmem_cache_alloc(_RET_IP_, b, c, flags, node); - } - - if (b && c->ctor) { - WARN_ON_ONCE(flags & __GFP_ZERO); - c->ctor(b); - } - - kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); - return b; -} - -void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) -{ - return slob_alloc_node(cachep, flags, NUMA_NO_NODE); -} -EXPORT_SYMBOL(kmem_cache_alloc); - - -void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags) -{ - return slob_alloc_node(cachep, flags, NUMA_NO_NODE); -} -EXPORT_SYMBOL(kmem_cache_alloc_lru); - -void *__kmalloc_node(size_t size, gfp_t gfp, int node) -{ - return __do_kmalloc_node(size, gfp, node, _RET_IP_); -} -EXPORT_SYMBOL(__kmalloc_node); - -void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node) -{ - return slob_alloc_node(cachep, gfp, node); -} -EXPORT_SYMBOL(kmem_cache_alloc_node); - -static void __kmem_cache_free(void *b, int size) -{ - if (size < PAGE_SIZE) - slob_free(b, size); - else - slob_free_pages(b, get_order(size)); -} - -static void kmem_rcu_free(struct rcu_head *head) -{ - struct slob_rcu *slob_rcu = (struct slob_rcu *)head; - void *b = (void *)slob_rcu - (slob_rcu->size - sizeof(struct slob_rcu)); - - __kmem_cache_free(b, slob_rcu->size); -} - -void kmem_cache_free(struct kmem_cache *c, void *b) -{ - kmemleak_free_recursive(b, c->flags); - trace_kmem_cache_free(_RET_IP_, b, c); - if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) { - struct slob_rcu *slob_rcu; - slob_rcu = b + (c->size - sizeof(struct slob_rcu)); - slob_rcu->size = c->size; - call_rcu(&slob_rcu->head, kmem_rcu_free); - } else { - __kmem_cache_free(b, c->size); - } -} -EXPORT_SYMBOL(kmem_cache_free); - -void kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p) -{ - size_t i; - - for (i = 0; i < nr; i++) { - if (s) - kmem_cache_free(s, p[i]); - else - kfree(p[i]); - } -} -EXPORT_SYMBOL(kmem_cache_free_bulk); - -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr, - void **p) -{ - size_t i; - - for (i = 0; i < nr; i++) { - void *x = p[i] = kmem_cache_alloc(s, flags); - - if (!x) { - kmem_cache_free_bulk(s, i, p); - return 0; - } - } - return i; -} -EXPORT_SYMBOL(kmem_cache_alloc_bulk); - -int __kmem_cache_shutdown(struct kmem_cache *c) -{ - /* No way to check for remaining objects */ - return 0; -} - -void __kmem_cache_release(struct kmem_cache *c) -{ -} - -int __kmem_cache_shrink(struct kmem_cache *d) -{ - return 0; -} - -static struct kmem_cache kmem_cache_boot = { - .name = "kmem_cache", - .size = sizeof(struct kmem_cache), - .flags = SLAB_PANIC, - .align = ARCH_KMALLOC_MINALIGN, -}; - -void __init kmem_cache_init(void) -{ - kmem_cache = &kmem_cache_boot; - slab_state = UP; -} - -void __init kmem_cache_init_late(void) -{ - slab_state = FULL; -} diff --git a/mm/slub.c b/mm/slub.c deleted file mode 100644 index 39327e98fce3..000000000000 --- a/mm/slub.c +++ /dev/null @@ -1,6506 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * SLUB: A slab allocator that limits cache line use instead of queuing - * objects in per cpu and per node lists. - * - * The allocator synchronizes using per slab locks or atomic operations - * and only uses a centralized lock to manage a pool of partial slabs. - * - * (C) 2007 SGI, Christoph Lameter - * (C) 2011 Linux Foundation, Christoph Lameter - */ - -#include <linux/mm.h> -#include <linux/swap.h> /* struct reclaim_state */ -#include <linux/module.h> -#include <linux/bit_spinlock.h> -#include <linux/interrupt.h> -#include <linux/swab.h> -#include <linux/bitops.h> -#include <linux/slab.h> -#include "slab.h" -#include <linux/proc_fs.h> -#include <linux/seq_file.h> -#include <linux/kasan.h> -#include <linux/kmsan.h> -#include <linux/cpu.h> -#include <linux/cpuset.h> -#include <linux/mempolicy.h> -#include <linux/ctype.h> -#include <linux/stackdepot.h> -#include <linux/debugobjects.h> -#include <linux/kallsyms.h> -#include <linux/kfence.h> -#include <linux/memory.h> -#include <linux/math64.h> -#include <linux/fault-inject.h> -#include <linux/stacktrace.h> -#include <linux/prefetch.h> -#include <linux/memcontrol.h> -#include <linux/random.h> -#include <kunit/test.h> -#include <kunit/test-bug.h> -#include <linux/sort.h> - -#include <linux/debugfs.h> -#include <trace/events/kmem.h> - -#include "internal.h" - -/* - * Lock order: - * 1. slab_mutex (Global Mutex) - * 2. node->list_lock (Spinlock) - * 3. kmem_cache->cpu_slab->lock (Local lock) - * 4. slab_lock(slab) (Only on some arches) - * 5. object_map_lock (Only for debugging) - * - * slab_mutex - * - * The role of the slab_mutex is to protect the list of all the slabs - * and to synchronize major metadata changes to slab cache structures. - * Also synchronizes memory hotplug callbacks. - * - * slab_lock - * - * The slab_lock is a wrapper around the page lock, thus it is a bit - * spinlock. - * - * The slab_lock is only used on arches that do not have the ability - * to do a cmpxchg_double. It only protects: - * - * A. slab->freelist -> List of free objects in a slab - * B. slab->inuse -> Number of objects in use - * C. slab->objects -> Number of objects in slab - * D. slab->frozen -> frozen state - * - * Frozen slabs - * - * If a slab is frozen then it is exempt from list management. It is not - * on any list except per cpu partial list. The processor that froze the - * slab is the one who can perform list operations on the slab. Other - * processors may put objects onto the freelist but the processor that - * froze the slab is the only one that can retrieve the objects from the - * slab's freelist. - * - * list_lock - * - * The list_lock protects the partial and full list on each node and - * the partial slab counter. If taken then no new slabs may be added or - * removed from the lists nor make the number of partial slabs be modified. - * (Note that the total number of slabs is an atomic value that may be - * modified without taking the list lock). - * - * The list_lock is a centralized lock and thus we avoid taking it as - * much as possible. As long as SLUB does not have to handle partial - * slabs, operations can continue without any centralized lock. F.e. - * allocating a long series of objects that fill up slabs does not require - * the list lock. - * - * For debug caches, all allocations are forced to go through a list_lock - * protected region to serialize against concurrent validation. - * - * cpu_slab->lock local lock - * - * This locks protect slowpath manipulation of all kmem_cache_cpu fields - * except the stat counters. This is a percpu structure manipulated only by - * the local cpu, so the lock protects against being preempted or interrupted - * by an irq. Fast path operations rely on lockless operations instead. - * - * On PREEMPT_RT, the local lock neither disables interrupts nor preemption - * which means the lockless fastpath cannot be used as it might interfere with - * an in-progress slow path operations. In this case the local lock is always - * taken but it still utilizes the freelist for the common operations. - * - * lockless fastpaths - * - * The fast path allocation (slab_alloc_node()) and freeing (do_slab_free()) - * are fully lockless when satisfied from the percpu slab (and when - * cmpxchg_double is possible to use, otherwise slab_lock is taken). - * They also don't disable preemption or migration or irqs. They rely on - * the transaction id (tid) field to detect being preempted or moved to - * another cpu. - * - * irq, preemption, migration considerations - * - * Interrupts are disabled as part of list_lock or local_lock operations, or - * around the slab_lock operation, in order to make the slab allocator safe - * to use in the context of an irq. - * - * In addition, preemption (or migration on PREEMPT_RT) is disabled in the - * allocation slowpath, bulk allocation, and put_cpu_partial(), so that the - * local cpu doesn't change in the process and e.g. the kmem_cache_cpu pointer - * doesn't have to be revalidated in each section protected by the local lock. - * - * SLUB assigns one slab for allocation to each processor. - * Allocations only occur from these slabs called cpu slabs. - * - * Slabs with free elements are kept on a partial list and during regular - * operations no list for full slabs is used. If an object in a full slab is - * freed then the slab will show up again on the partial lists. - * We track full slabs for debugging purposes though because otherwise we - * cannot scan all objects. - * - * Slabs are freed when they become empty. Teardown and setup is - * minimal so we rely on the page allocators per cpu caches for - * fast frees and allocs. - * - * slab->frozen The slab is frozen and exempt from list processing. - * This means that the slab is dedicated to a purpose - * such as satisfying allocations for a specific - * processor. Objects may be freed in the slab while - * it is frozen but slab_free will then skip the usual - * list operations. It is up to the processor holding - * the slab to integrate the slab into the slab lists - * when the slab is no longer needed. - * - * One use of this flag is to mark slabs that are - * used for allocations. Then such a slab becomes a cpu - * slab. The cpu slab may be equipped with an additional - * freelist that allows lockless access to - * free objects in addition to the regular freelist - * that requires the slab lock. - * - * SLAB_DEBUG_FLAGS Slab requires special handling due to debug - * options set. This moves slab handling out of - * the fast path and disables lockless freelists. - */ - -/* - * We could simply use migrate_disable()/enable() but as long as it's a - * function call even on !PREEMPT_RT, use inline preempt_disable() there. - */ -#ifndef CONFIG_PREEMPT_RT -#define slub_get_cpu_ptr(var) get_cpu_ptr(var) -#define slub_put_cpu_ptr(var) put_cpu_ptr(var) -#define USE_LOCKLESS_FAST_PATH() (true) -#else -#define slub_get_cpu_ptr(var) \ -({ \ - migrate_disable(); \ - this_cpu_ptr(var); \ -}) -#define slub_put_cpu_ptr(var) \ -do { \ - (void)(var); \ - migrate_enable(); \ -} while (0) -#define USE_LOCKLESS_FAST_PATH() (false) -#endif - -#ifndef CONFIG_SLUB_TINY -#define __fastpath_inline __always_inline -#else -#define __fastpath_inline -#endif - -#ifdef CONFIG_SLUB_DEBUG -#ifdef CONFIG_SLUB_DEBUG_ON -DEFINE_STATIC_KEY_TRUE(slub_debug_enabled); -#else -DEFINE_STATIC_KEY_FALSE(slub_debug_enabled); -#endif -#endif /* CONFIG_SLUB_DEBUG */ - -/* Structure holding parameters for get_partial() call chain */ -struct partial_context { - struct slab **slab; - gfp_t flags; - unsigned int orig_size; -}; - -static inline bool kmem_cache_debug(struct kmem_cache *s) -{ - return kmem_cache_debug_flags(s, SLAB_DEBUG_FLAGS); -} - -static inline bool slub_debug_orig_size(struct kmem_cache *s) -{ - return (kmem_cache_debug_flags(s, SLAB_STORE_USER) && - (s->flags & SLAB_KMALLOC)); -} - -void *fixup_red_left(struct kmem_cache *s, void *p) -{ - if (kmem_cache_debug_flags(s, SLAB_RED_ZONE)) - p += s->red_left_pad; - - return p; -} - -static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s) -{ -#ifdef CONFIG_SLUB_CPU_PARTIAL - return !kmem_cache_debug(s); -#else - return false; -#endif -} - -/* - * Issues still to be resolved: - * - * - Support PAGE_ALLOC_DEBUG. Should be easy to do. - * - * - Variable sizing of the per node arrays - */ - -/* Enable to log cmpxchg failures */ -#undef SLUB_DEBUG_CMPXCHG - -#ifndef CONFIG_SLUB_TINY -/* - * Minimum number of partial slabs. These will be left on the partial - * lists even if they are empty. kmem_cache_shrink may reclaim them. - */ -#define MIN_PARTIAL 5 - -/* - * Maximum number of desirable partial slabs. - * The existence of more partial slabs makes kmem_cache_shrink - * sort the partial list by the number of objects in use. - */ -#define MAX_PARTIAL 10 -#else -#define MIN_PARTIAL 0 -#define MAX_PARTIAL 0 -#endif - -#define DEBUG_DEFAULT_FLAGS (SLAB_CONSISTENCY_CHECKS | SLAB_RED_ZONE | \ - SLAB_POISON | SLAB_STORE_USER) - -/* - * These debug flags cannot use CMPXCHG because there might be consistency - * issues when checking or reading debug information - */ -#define SLAB_NO_CMPXCHG (SLAB_CONSISTENCY_CHECKS | SLAB_STORE_USER | \ - SLAB_TRACE) - - -/* - * Debugging flags that require metadata to be stored in the slab. These get - * disabled when slub_debug=O is used and a cache's min order increases with - * metadata. - */ -#define DEBUG_METADATA_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) - -#define OO_SHIFT 16 -#define OO_MASK ((1 << OO_SHIFT) - 1) -#define MAX_OBJS_PER_PAGE 32767 /* since slab.objects is u15 */ - -/* Internal SLUB flags */ -/* Poison object */ -#define __OBJECT_POISON ((slab_flags_t __force)0x80000000U) -/* Use cmpxchg_double */ -#define __CMPXCHG_DOUBLE ((slab_flags_t __force)0x40000000U) - -/* - * Tracking user of a slab. - */ -#define TRACK_ADDRS_COUNT 16 -struct track { - unsigned long addr; /* Called from address */ -#ifdef CONFIG_STACKDEPOT - depot_stack_handle_t handle; -#endif - int cpu; /* Was running on cpu */ - int pid; /* Pid context */ - unsigned long when; /* When did the operation occur */ -}; - -enum track_item { TRACK_ALLOC, TRACK_FREE }; - -#ifdef SLAB_SUPPORTS_SYSFS -static int sysfs_slab_add(struct kmem_cache *); -static int sysfs_slab_alias(struct kmem_cache *, const char *); -#else -static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; } -static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) - { return 0; } -#endif - -#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) -static void debugfs_slab_add(struct kmem_cache *); -#else -static inline void debugfs_slab_add(struct kmem_cache *s) { } -#endif - -static inline void stat(const struct kmem_cache *s, enum stat_item si) -{ -#ifdef CONFIG_SLUB_STATS - /* - * The rmw is racy on a preemptible kernel but this is acceptable, so - * avoid this_cpu_add()'s irq-disable overhead. - */ - raw_cpu_inc(s->cpu_slab->stat[si]); -#endif -} - -/* - * Tracks for which NUMA nodes we have kmem_cache_nodes allocated. - * Corresponds to node_state[N_NORMAL_MEMORY], but can temporarily - * differ during memory hotplug/hotremove operations. - * Protected by slab_mutex. - */ -static nodemask_t slab_nodes; - -#ifndef CONFIG_SLUB_TINY -/* - * Workqueue used for flush_cpu_slab(). - */ -static struct workqueue_struct *flushwq; -#endif - -/******************************************************************** - * Core slab cache functions - *******************************************************************/ - -/* - * Returns freelist pointer (ptr). With hardening, this is obfuscated - * with an XOR of the address where the pointer is held and a per-cache - * random number. - */ -static inline void *freelist_ptr(const struct kmem_cache *s, void *ptr, - unsigned long ptr_addr) -{ -#ifdef CONFIG_SLAB_FREELIST_HARDENED - /* - * When CONFIG_KASAN_SW/HW_TAGS is enabled, ptr_addr might be tagged. - * Normally, this doesn't cause any issues, as both set_freepointer() - * and get_freepointer() are called with a pointer with the same tag. - * However, there are some issues with CONFIG_SLUB_DEBUG code. For - * example, when __free_slub() iterates over objects in a cache, it - * passes untagged pointers to check_object(). check_object() in turns - * calls get_freepointer() with an untagged pointer, which causes the - * freepointer to be restored incorrectly. - */ - return (void *)((unsigned long)ptr ^ s->random ^ - swab((unsigned long)kasan_reset_tag((void *)ptr_addr))); -#else - return ptr; -#endif -} - -/* Returns the freelist pointer recorded at location ptr_addr. */ -static inline void *freelist_dereference(const struct kmem_cache *s, - void *ptr_addr) -{ - return freelist_ptr(s, (void *)*(unsigned long *)(ptr_addr), - (unsigned long)ptr_addr); -} - -static inline void *get_freepointer(struct kmem_cache *s, void *object) -{ - object = kasan_reset_tag(object); - return freelist_dereference(s, object + s->offset); -} - -#ifndef CONFIG_SLUB_TINY -static void prefetch_freepointer(const struct kmem_cache *s, void *object) -{ - prefetchw(object + s->offset); -} -#endif - -/* - * When running under KMSAN, get_freepointer_safe() may return an uninitialized - * pointer value in the case the current thread loses the race for the next - * memory chunk in the freelist. In that case this_cpu_cmpxchg_double() in - * slab_alloc_node() will fail, so the uninitialized value won't be used, but - * KMSAN will still check all arguments of cmpxchg because of imperfect - * handling of inline assembly. - * To work around this problem, we apply __no_kmsan_checks to ensure that - * get_freepointer_safe() returns initialized memory. - */ -__no_kmsan_checks -static inline void *get_freepointer_safe(struct kmem_cache *s, void *object) -{ - unsigned long freepointer_addr; - void *p; - - if (!debug_pagealloc_enabled_static()) - return get_freepointer(s, object); - - object = kasan_reset_tag(object); - freepointer_addr = (unsigned long)object + s->offset; - copy_from_kernel_nofault(&p, (void **)freepointer_addr, sizeof(p)); - return freelist_ptr(s, p, freepointer_addr); -} - -static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) -{ - unsigned long freeptr_addr = (unsigned long)object + s->offset; - -#ifdef CONFIG_SLAB_FREELIST_HARDENED - BUG_ON(object == fp); /* naive detection of double free or corruption */ -#endif - - freeptr_addr = (unsigned long)kasan_reset_tag((void *)freeptr_addr); - *(void **)freeptr_addr = freelist_ptr(s, fp, freeptr_addr); -} - -/* Loop over all objects in a slab */ -#define for_each_object(__p, __s, __addr, __objects) \ - for (__p = fixup_red_left(__s, __addr); \ - __p < (__addr) + (__objects) * (__s)->size; \ - __p += (__s)->size) - -static inline unsigned int order_objects(unsigned int order, unsigned int size) -{ - return ((unsigned int)PAGE_SIZE << order) / size; -} - -static inline struct kmem_cache_order_objects oo_make(unsigned int order, - unsigned int size) -{ - struct kmem_cache_order_objects x = { - (order << OO_SHIFT) + order_objects(order, size) - }; - - return x; -} - -static inline unsigned int oo_order(struct kmem_cache_order_objects x) -{ - return x.x >> OO_SHIFT; -} - -static inline unsigned int oo_objects(struct kmem_cache_order_objects x) -{ - return x.x & OO_MASK; -} - -#ifdef CONFIG_SLUB_CPU_PARTIAL -static void slub_set_cpu_partial(struct kmem_cache *s, unsigned int nr_objects) -{ - unsigned int nr_slabs; - - s->cpu_partial = nr_objects; - - /* - * We take the number of objects but actually limit the number of - * slabs on the per cpu partial list, in order to limit excessive - * growth of the list. For simplicity we assume that the slabs will - * be half-full. - */ - nr_slabs = DIV_ROUND_UP(nr_objects * 2, oo_objects(s->oo)); - s->cpu_partial_slabs = nr_slabs; -} -#else -static inline void -slub_set_cpu_partial(struct kmem_cache *s, unsigned int nr_objects) -{ -} -#endif /* CONFIG_SLUB_CPU_PARTIAL */ - -/* - * Per slab locking using the pagelock - */ -static __always_inline void slab_lock(struct slab *slab) -{ - struct page *page = slab_page(slab); - - VM_BUG_ON_PAGE(PageTail(page), page); - bit_spin_lock(PG_locked, &page->flags); -} - -static __always_inline void slab_unlock(struct slab *slab) -{ - struct page *page = slab_page(slab); - - VM_BUG_ON_PAGE(PageTail(page), page); - __bit_spin_unlock(PG_locked, &page->flags); -} - -/* - * Interrupts must be disabled (for the fallback code to work right), typically - * by an _irqsave() lock variant. On PREEMPT_RT the preempt_disable(), which is - * part of bit_spin_lock(), is sufficient because the policy is not to allow any - * allocation/ free operation in hardirq context. Therefore nothing can - * interrupt the operation. - */ -static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab, - void *freelist_old, unsigned long counters_old, - void *freelist_new, unsigned long counters_new, - const char *n) -{ - if (USE_LOCKLESS_FAST_PATH()) - lockdep_assert_irqs_disabled(); -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) - if (s->flags & __CMPXCHG_DOUBLE) { - if (cmpxchg_double(&slab->freelist, &slab->counters, - freelist_old, counters_old, - freelist_new, counters_new)) - return true; - } else -#endif - { - slab_lock(slab); - if (slab->freelist == freelist_old && - slab->counters == counters_old) { - slab->freelist = freelist_new; - slab->counters = counters_new; - slab_unlock(slab); - return true; - } - slab_unlock(slab); - } - - cpu_relax(); - stat(s, CMPXCHG_DOUBLE_FAIL); - -#ifdef SLUB_DEBUG_CMPXCHG - pr_info("%s %s: cmpxchg double redo ", n, s->name); -#endif - - return false; -} - -static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab, - void *freelist_old, unsigned long counters_old, - void *freelist_new, unsigned long counters_new, - const char *n) -{ -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) - if (s->flags & __CMPXCHG_DOUBLE) { - if (cmpxchg_double(&slab->freelist, &slab->counters, - freelist_old, counters_old, - freelist_new, counters_new)) - return true; - } else -#endif - { - unsigned long flags; - - local_irq_save(flags); - slab_lock(slab); - if (slab->freelist == freelist_old && - slab->counters == counters_old) { - slab->freelist = freelist_new; - slab->counters = counters_new; - slab_unlock(slab); - local_irq_restore(flags); - return true; - } - slab_unlock(slab); - local_irq_restore(flags); - } - - cpu_relax(); - stat(s, CMPXCHG_DOUBLE_FAIL); - -#ifdef SLUB_DEBUG_CMPXCHG - pr_info("%s %s: cmpxchg double redo ", n, s->name); -#endif - - return false; -} - -#ifdef CONFIG_SLUB_DEBUG -static unsigned long object_map[BITS_TO_LONGS(MAX_OBJS_PER_PAGE)]; -static DEFINE_SPINLOCK(object_map_lock); - -static void __fill_map(unsigned long *obj_map, struct kmem_cache *s, - struct slab *slab) -{ - void *addr = slab_address(slab); - void *p; - - bitmap_zero(obj_map, slab->objects); - - for (p = slab->freelist; p; p = get_freepointer(s, p)) - set_bit(__obj_to_index(s, addr, p), obj_map); -} - -#if IS_ENABLED(CONFIG_KUNIT) -static bool slab_add_kunit_errors(void) -{ - struct kunit_resource *resource; - - if (!kunit_get_current_test()) - return false; - - resource = kunit_find_named_resource(current->kunit_test, "slab_errors"); - if (!resource) - return false; - - (*(int *)resource->data)++; - kunit_put_resource(resource); - return true; -} -#else -static inline bool slab_add_kunit_errors(void) { return false; } -#endif - -static inline unsigned int size_from_object(struct kmem_cache *s) -{ - if (s->flags & SLAB_RED_ZONE) - return s->size - s->red_left_pad; - - return s->size; -} - -static inline void *restore_red_left(struct kmem_cache *s, void *p) -{ - if (s->flags & SLAB_RED_ZONE) - p -= s->red_left_pad; - - return p; -} - -/* - * Debug settings: - */ -#if defined(CONFIG_SLUB_DEBUG_ON) -static slab_flags_t slub_debug = DEBUG_DEFAULT_FLAGS; -#else -static slab_flags_t slub_debug; -#endif - -static char *slub_debug_string; -static int disable_higher_order_debug; - -/* - * slub is about to manipulate internal object metadata. This memory lies - * outside the range of the allocated object, so accessing it would normally - * be reported by kasan as a bounds error. metadata_access_enable() is used - * to tell kasan that these accesses are OK. - */ -static inline void metadata_access_enable(void) -{ - kasan_disable_current(); -} - -static inline void metadata_access_disable(void) -{ - kasan_enable_current(); -} - -/* - * Object debugging - */ - -/* Verify that a pointer has an address that is valid within a slab page */ -static inline int check_valid_pointer(struct kmem_cache *s, - struct slab *slab, void *object) -{ - void *base; - - if (!object) - return 1; - - base = slab_address(slab); - object = kasan_reset_tag(object); - object = restore_red_left(s, object); - if (object < base || object >= base + slab->objects * s->size || - (object - base) % s->size) { - return 0; - } - - return 1; -} - -static void print_section(char *level, char *text, u8 *addr, - unsigned int length) -{ - metadata_access_enable(); - print_hex_dump(level, text, DUMP_PREFIX_ADDRESS, - 16, 1, kasan_reset_tag((void *)addr), length, 1); - metadata_access_disable(); -} - -/* - * See comment in calculate_sizes(). - */ -static inline bool freeptr_outside_object(struct kmem_cache *s) -{ - return s->offset >= s->inuse; -} - -/* - * Return offset of the end of info block which is inuse + free pointer if - * not overlapping with object. - */ -static inline unsigned int get_info_end(struct kmem_cache *s) -{ - if (freeptr_outside_object(s)) - return s->inuse + sizeof(void *); - else - return s->inuse; -} - -static struct track *get_track(struct kmem_cache *s, void *object, - enum track_item alloc) -{ - struct track *p; - - p = object + get_info_end(s); - - return kasan_reset_tag(p + alloc); -} - -#ifdef CONFIG_STACKDEPOT -static noinline depot_stack_handle_t set_track_prepare(void) -{ - depot_stack_handle_t handle; - unsigned long entries[TRACK_ADDRS_COUNT]; - unsigned int nr_entries; - - nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 3); - handle = stack_depot_save(entries, nr_entries, GFP_NOWAIT); - - return handle; -} -#else -static inline depot_stack_handle_t set_track_prepare(void) -{ - return 0; -} -#endif - -static void set_track_update(struct kmem_cache *s, void *object, - enum track_item alloc, unsigned long addr, - depot_stack_handle_t handle) -{ - struct track *p = get_track(s, object, alloc); - -#ifdef CONFIG_STACKDEPOT - p->handle = handle; -#endif - p->addr = addr; - p->cpu = smp_processor_id(); - p->pid = current->pid; - p->when = jiffies; -} - -static __always_inline void set_track(struct kmem_cache *s, void *object, - enum track_item alloc, unsigned long addr) -{ - depot_stack_handle_t handle = set_track_prepare(); - - set_track_update(s, object, alloc, addr, handle); -} - -static void init_tracking(struct kmem_cache *s, void *object) -{ - struct track *p; - - if (!(s->flags & SLAB_STORE_USER)) - return; - - p = get_track(s, object, TRACK_ALLOC); - memset(p, 0, 2*sizeof(struct track)); -} - -static void print_track(const char *s, struct track *t, unsigned long pr_time) -{ - depot_stack_handle_t handle __maybe_unused; - - if (!t->addr) - return; - - pr_err("%s in %pS age=%lu cpu=%u pid=%d\n", - s, (void *)t->addr, pr_time - t->when, t->cpu, t->pid); -#ifdef CONFIG_STACKDEPOT - handle = READ_ONCE(t->handle); - if (handle) - stack_depot_print(handle); - else - pr_err("object allocation/free stack trace missing\n"); -#endif -} - -void print_tracking(struct kmem_cache *s, void *object) -{ - unsigned long pr_time = jiffies; - if (!(s->flags & SLAB_STORE_USER)) - return; - - print_track("Allocated", get_track(s, object, TRACK_ALLOC), pr_time); - print_track("Freed", get_track(s, object, TRACK_FREE), pr_time); -} - -static void print_slab_info(const struct slab *slab) -{ - struct folio *folio = (struct folio *)slab_folio(slab); - - pr_err("Slab 0x%p objects=%u used=%u fp=0x%p flags=%pGp\n", - slab, slab->objects, slab->inuse, slab->freelist, - folio_flags(folio, 0)); -} - -/* - * kmalloc caches has fixed sizes (mostly power of 2), and kmalloc() API - * family will round up the real request size to these fixed ones, so - * there could be an extra area than what is requested. Save the original - * request size in the meta data area, for better debug and sanity check. - */ -static inline void set_orig_size(struct kmem_cache *s, - void *object, unsigned int orig_size) -{ - void *p = kasan_reset_tag(object); - - if (!slub_debug_orig_size(s)) - return; - -#ifdef CONFIG_KASAN_GENERIC - /* - * KASAN could save its free meta data in object's data area at - * offset 0, if the size is larger than 'orig_size', it will - * overlap the data redzone in [orig_size+1, object_size], and - * the check should be skipped. - */ - if (kasan_metadata_size(s, true) > orig_size) - orig_size = s->object_size; -#endif - - p += get_info_end(s); - p += sizeof(struct track) * 2; - - *(unsigned int *)p = orig_size; -} - -static inline unsigned int get_orig_size(struct kmem_cache *s, void *object) -{ - void *p = kasan_reset_tag(object); - - if (!slub_debug_orig_size(s)) - return s->object_size; - - p += get_info_end(s); - p += sizeof(struct track) * 2; - - return *(unsigned int *)p; -} - -void skip_orig_size_check(struct kmem_cache *s, const void *object) -{ - set_orig_size(s, (void *)object, s->object_size); -} - -static void slab_bug(struct kmem_cache *s, char *fmt, ...) -{ - struct va_format vaf; - va_list args; - - va_start(args, fmt); - vaf.fmt = fmt; - vaf.va = &args; - pr_err("=============================================================================\n"); - pr_err("BUG %s (%s): %pV\n", s->name, print_tainted(), &vaf); - pr_err("-----------------------------------------------------------------------------\n\n"); - va_end(args); -} - -__printf(2, 3) -static void slab_fix(struct kmem_cache *s, char *fmt, ...) -{ - struct va_format vaf; - va_list args; - - if (slab_add_kunit_errors()) - return; - - va_start(args, fmt); - vaf.fmt = fmt; - vaf.va = &args; - pr_err("FIX %s: %pV\n", s->name, &vaf); - va_end(args); -} - -static void print_trailer(struct kmem_cache *s, struct slab *slab, u8 *p) -{ - unsigned int off; /* Offset of last byte */ - u8 *addr = slab_address(slab); - - print_tracking(s, p); - - print_slab_info(slab); - - pr_err("Object 0x%p @offset=%tu fp=0x%p\n\n", - p, p - addr, get_freepointer(s, p)); - - if (s->flags & SLAB_RED_ZONE) - print_section(KERN_ERR, "Redzone ", p - s->red_left_pad, - s->red_left_pad); - else if (p > addr + 16) - print_section(KERN_ERR, "Bytes b4 ", p - 16, 16); - - print_section(KERN_ERR, "Object ", p, - min_t(unsigned int, s->object_size, PAGE_SIZE)); - if (s->flags & SLAB_RED_ZONE) - print_section(KERN_ERR, "Redzone ", p + s->object_size, - s->inuse - s->object_size); - - off = get_info_end(s); - - if (s->flags & SLAB_STORE_USER) - off += 2 * sizeof(struct track); - - if (slub_debug_orig_size(s)) - off += sizeof(unsigned int); - - off += kasan_metadata_size(s, false); - - if (off != size_from_object(s)) - /* Beginning of the filler is the free pointer */ - print_section(KERN_ERR, "Padding ", p + off, - size_from_object(s) - off); - - dump_stack(); -} - -static void object_err(struct kmem_cache *s, struct slab *slab, - u8 *object, char *reason) -{ - if (slab_add_kunit_errors()) - return; - - slab_bug(s, "%s", reason); - print_trailer(s, slab, object); - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); -} - -static bool freelist_corrupted(struct kmem_cache *s, struct slab *slab, - void **freelist, void *nextfree) -{ - if ((s->flags & SLAB_CONSISTENCY_CHECKS) && - !check_valid_pointer(s, slab, nextfree) && freelist) { - object_err(s, slab, *freelist, "Freechain corrupt"); - *freelist = NULL; - slab_fix(s, "Isolate corrupted freechain"); - return true; - } - - return false; -} - -static __printf(3, 4) void slab_err(struct kmem_cache *s, struct slab *slab, - const char *fmt, ...) -{ - va_list args; - char buf[100]; - - if (slab_add_kunit_errors()) - return; - - va_start(args, fmt); - vsnprintf(buf, sizeof(buf), fmt, args); - va_end(args); - slab_bug(s, "%s", buf); - print_slab_info(slab); - dump_stack(); - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); -} - -static void init_object(struct kmem_cache *s, void *object, u8 val) -{ - u8 *p = kasan_reset_tag(object); - unsigned int poison_size = s->object_size; - - if (s->flags & SLAB_RED_ZONE) { - memset(p - s->red_left_pad, val, s->red_left_pad); - - if (slub_debug_orig_size(s) && val == SLUB_RED_ACTIVE) { - /* - * Redzone the extra allocated space by kmalloc than - * requested, and the poison size will be limited to - * the original request size accordingly. - */ - poison_size = get_orig_size(s, object); - } - } - - if (s->flags & __OBJECT_POISON) { - memset(p, POISON_FREE, poison_size - 1); - p[poison_size - 1] = POISON_END; - } - - if (s->flags & SLAB_RED_ZONE) - memset(p + poison_size, val, s->inuse - poison_size); -} - -static void restore_bytes(struct kmem_cache *s, char *message, u8 data, - void *from, void *to) -{ - slab_fix(s, "Restoring %s 0x%p-0x%p=0x%x", message, from, to - 1, data); - memset(from, data, to - from); -} - -static int check_bytes_and_report(struct kmem_cache *s, struct slab *slab, - u8 *object, char *what, - u8 *start, unsigned int value, unsigned int bytes) -{ - u8 *fault; - u8 *end; - u8 *addr = slab_address(slab); - - metadata_access_enable(); - fault = memchr_inv(kasan_reset_tag(start), value, bytes); - metadata_access_disable(); - if (!fault) - return 1; - - end = start + bytes; - while (end > fault && end[-1] == value) - end--; - - if (slab_add_kunit_errors()) - goto skip_bug_print; - - slab_bug(s, "%s overwritten", what); - pr_err("0x%p-0x%p @offset=%tu. First byte 0x%x instead of 0x%x\n", - fault, end - 1, fault - addr, - fault[0], value); - print_trailer(s, slab, object); - add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); - -skip_bug_print: - restore_bytes(s, what, value, fault, end); - return 0; -} - -/* - * Object layout: - * - * object address - * Bytes of the object to be managed. - * If the freepointer may overlay the object then the free - * pointer is at the middle of the object. - * - * Poisoning uses 0x6b (POISON_FREE) and the last byte is - * 0xa5 (POISON_END) - * - * object + s->object_size - * Padding to reach word boundary. This is also used for Redzoning. - * Padding is extended by another word if Redzoning is enabled and - * object_size == inuse. - * - * We fill with 0xbb (RED_INACTIVE) for inactive objects and with - * 0xcc (RED_ACTIVE) for objects in use. - * - * object + s->inuse - * Meta data starts here. - * - * A. Free pointer (if we cannot overwrite object on free) - * B. Tracking data for SLAB_STORE_USER - * C. Original request size for kmalloc object (SLAB_STORE_USER enabled) - * D. Padding to reach required alignment boundary or at minimum - * one word if debugging is on to be able to detect writes - * before the word boundary. - * - * Padding is done using 0x5a (POISON_INUSE) - * - * object + s->size - * Nothing is used beyond s->size. - * - * If slabcaches are merged then the object_size and inuse boundaries are mostly - * ignored. And therefore no slab options that rely on these boundaries - * may be used with merged slabcaches. - */ - -static int check_pad_bytes(struct kmem_cache *s, struct slab *slab, u8 *p) -{ - unsigned long off = get_info_end(s); /* The end of info */ - - if (s->flags & SLAB_STORE_USER) { - /* We also have user information there */ - off += 2 * sizeof(struct track); - - if (s->flags & SLAB_KMALLOC) - off += sizeof(unsigned int); - } - - off += kasan_metadata_size(s, false); - - if (size_from_object(s) == off) - return 1; - - return check_bytes_and_report(s, slab, p, "Object padding", - p + off, POISON_INUSE, size_from_object(s) - off); -} - -/* Check the pad bytes at the end of a slab page */ -static void slab_pad_check(struct kmem_cache *s, struct slab *slab) -{ - u8 *start; - u8 *fault; - u8 *end; - u8 *pad; - int length; - int remainder; - - if (!(s->flags & SLAB_POISON)) - return; - - start = slab_address(slab); - length = slab_size(slab); - end = start + length; - remainder = length % s->size; - if (!remainder) - return; - - pad = end - remainder; - metadata_access_enable(); - fault = memchr_inv(kasan_reset_tag(pad), POISON_INUSE, remainder); - metadata_access_disable(); - if (!fault) - return; - while (end > fault && end[-1] == POISON_INUSE) - end--; - - slab_err(s, slab, "Padding overwritten. 0x%p-0x%p @offset=%tu", - fault, end - 1, fault - start); - print_section(KERN_ERR, "Padding ", pad, remainder); - - restore_bytes(s, "slab padding", POISON_INUSE, fault, end); -} - -static int check_object(struct kmem_cache *s, struct slab *slab, - void *object, u8 val) -{ - u8 *p = object; - u8 *endobject = object + s->object_size; - unsigned int orig_size; - - if (s->flags & SLAB_RED_ZONE) { - if (!check_bytes_and_report(s, slab, object, "Left Redzone", - object - s->red_left_pad, val, s->red_left_pad)) - return 0; - - if (!check_bytes_and_report(s, slab, object, "Right Redzone", - endobject, val, s->inuse - s->object_size)) - return 0; - - if (slub_debug_orig_size(s) && val == SLUB_RED_ACTIVE) { - orig_size = get_orig_size(s, object); - - if (s->object_size > orig_size && - !check_bytes_and_report(s, slab, object, - "kmalloc Redzone", p + orig_size, - val, s->object_size - orig_size)) { - return 0; - } - } - } else { - if ((s->flags & SLAB_POISON) && s->object_size < s->inuse) { - check_bytes_and_report(s, slab, p, "Alignment padding", - endobject, POISON_INUSE, - s->inuse - s->object_size); - } - } - - if (s->flags & SLAB_POISON) { - if (val != SLUB_RED_ACTIVE && (s->flags & __OBJECT_POISON) && - (!check_bytes_and_report(s, slab, p, "Poison", p, - POISON_FREE, s->object_size - 1) || - !check_bytes_and_report(s, slab, p, "End Poison", - p + s->object_size - 1, POISON_END, 1))) - return 0; - /* - * check_pad_bytes cleans up on its own. - */ - check_pad_bytes(s, slab, p); - } - - if (!freeptr_outside_object(s) && val == SLUB_RED_ACTIVE) - /* - * Object and freepointer overlap. Cannot check - * freepointer while object is allocated. - */ - return 1; - - /* Check free pointer validity */ - if (!check_valid_pointer(s, slab, get_freepointer(s, p))) { - object_err(s, slab, p, "Freepointer corrupt"); - /* - * No choice but to zap it and thus lose the remainder - * of the free objects in this slab. May cause - * another error because the object count is now wrong. - */ - set_freepointer(s, p, NULL); - return 0; - } - return 1; -} - -static int check_slab(struct kmem_cache *s, struct slab *slab) -{ - int maxobj; - - if (!folio_test_slab(slab_folio(slab))) { - slab_err(s, slab, "Not a valid slab page"); - return 0; - } - - maxobj = order_objects(slab_order(slab), s->size); - if (slab->objects > maxobj) { - slab_err(s, slab, "objects %u > max %u", - slab->objects, maxobj); - return 0; - } - if (slab->inuse > slab->objects) { - slab_err(s, slab, "inuse %u > max %u", - slab->inuse, slab->objects); - return 0; - } - /* Slab_pad_check fixes things up after itself */ - slab_pad_check(s, slab); - return 1; -} - -/* - * Determine if a certain object in a slab is on the freelist. Must hold the - * slab lock to guarantee that the chains are in a consistent state. - */ -static int on_freelist(struct kmem_cache *s, struct slab *slab, void *search) -{ - int nr = 0; - void *fp; - void *object = NULL; - int max_objects; - - fp = slab->freelist; - while (fp && nr <= slab->objects) { - if (fp == search) - return 1; - if (!check_valid_pointer(s, slab, fp)) { - if (object) { - object_err(s, slab, object, - "Freechain corrupt"); - set_freepointer(s, object, NULL); - } else { - slab_err(s, slab, "Freepointer corrupt"); - slab->freelist = NULL; - slab->inuse = slab->objects; - slab_fix(s, "Freelist cleared"); - return 0; - } - break; - } - object = fp; - fp = get_freepointer(s, object); - nr++; - } - - max_objects = order_objects(slab_order(slab), s->size); - if (max_objects > MAX_OBJS_PER_PAGE) - max_objects = MAX_OBJS_PER_PAGE; - - if (slab->objects != max_objects) { - slab_err(s, slab, "Wrong number of objects. Found %d but should be %d", - slab->objects, max_objects); - slab->objects = max_objects; - slab_fix(s, "Number of objects adjusted"); - } - if (slab->inuse != slab->objects - nr) { - slab_err(s, slab, "Wrong object count. Counter is %d but counted were %d", - slab->inuse, slab->objects - nr); - slab->inuse = slab->objects - nr; - slab_fix(s, "Object count adjusted"); - } - return search == NULL; -} - -static void trace(struct kmem_cache *s, struct slab *slab, void *object, - int alloc) -{ - if (s->flags & SLAB_TRACE) { - pr_info("TRACE %s %s 0x%p inuse=%d fp=0x%p\n", - s->name, - alloc ? "alloc" : "free", - object, slab->inuse, - slab->freelist); - - if (!alloc) - print_section(KERN_INFO, "Object ", (void *)object, - s->object_size); - - dump_stack(); - } -} - -/* - * Tracking of fully allocated slabs for debugging purposes. - */ -static void add_full(struct kmem_cache *s, - struct kmem_cache_node *n, struct slab *slab) -{ - if (!(s->flags & SLAB_STORE_USER)) - return; - - lockdep_assert_held(&n->list_lock); - list_add(&slab->slab_list, &n->full); -} - -static void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, struct slab *slab) -{ - if (!(s->flags & SLAB_STORE_USER)) - return; - - lockdep_assert_held(&n->list_lock); - list_del(&slab->slab_list); -} - -/* Tracking of the number of slabs for debugging purposes */ -static inline unsigned long slabs_node(struct kmem_cache *s, int node) -{ - struct kmem_cache_node *n = get_node(s, node); - - return atomic_long_read(&n->nr_slabs); -} - -static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) -{ - return atomic_long_read(&n->nr_slabs); -} - -static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects) -{ - struct kmem_cache_node *n = get_node(s, node); - - /* - * May be called early in order to allocate a slab for the - * kmem_cache_node structure. Solve the chicken-egg - * dilemma by deferring the increment of the count during - * bootstrap (see early_kmem_cache_node_alloc). - */ - if (likely(n)) { - atomic_long_inc(&n->nr_slabs); - atomic_long_add(objects, &n->total_objects); - } -} -static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects) -{ - struct kmem_cache_node *n = get_node(s, node); - - atomic_long_dec(&n->nr_slabs); - atomic_long_sub(objects, &n->total_objects); -} - -/* Object debug checks for alloc/free paths */ -static void setup_object_debug(struct kmem_cache *s, void *object) -{ - if (!kmem_cache_debug_flags(s, SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON)) - return; - - init_object(s, object, SLUB_RED_INACTIVE); - init_tracking(s, object); -} - -static -void setup_slab_debug(struct kmem_cache *s, struct slab *slab, void *addr) -{ - if (!kmem_cache_debug_flags(s, SLAB_POISON)) - return; - - metadata_access_enable(); - memset(kasan_reset_tag(addr), POISON_INUSE, slab_size(slab)); - metadata_access_disable(); -} - -static inline int alloc_consistency_checks(struct kmem_cache *s, - struct slab *slab, void *object) -{ - if (!check_slab(s, slab)) - return 0; - - if (!check_valid_pointer(s, slab, object)) { - object_err(s, slab, object, "Freelist Pointer check fails"); - return 0; - } - - if (!check_object(s, slab, object, SLUB_RED_INACTIVE)) - return 0; - - return 1; -} - -static noinline bool alloc_debug_processing(struct kmem_cache *s, - struct slab *slab, void *object, int orig_size) -{ - if (s->flags & SLAB_CONSISTENCY_CHECKS) { - if (!alloc_consistency_checks(s, slab, object)) - goto bad; - } - - /* Success. Perform special debug activities for allocs */ - trace(s, slab, object, 1); - set_orig_size(s, object, orig_size); - init_object(s, object, SLUB_RED_ACTIVE); - return true; - -bad: - if (folio_test_slab(slab_folio(slab))) { - /* - * If this is a slab page then lets do the best we can - * to avoid issues in the future. Marking all objects - * as used avoids touching the remaining objects. - */ - slab_fix(s, "Marking all objects used"); - slab->inuse = slab->objects; - slab->freelist = NULL; - } - return false; -} - -static inline int free_consistency_checks(struct kmem_cache *s, - struct slab *slab, void *object, unsigned long addr) -{ - if (!check_valid_pointer(s, slab, object)) { - slab_err(s, slab, "Invalid object pointer 0x%p", object); - return 0; - } - - if (on_freelist(s, slab, object)) { - object_err(s, slab, object, "Object already free"); - return 0; - } - - if (!check_object(s, slab, object, SLUB_RED_ACTIVE)) - return 0; - - if (unlikely(s != slab->slab_cache)) { - if (!folio_test_slab(slab_folio(slab))) { - slab_err(s, slab, "Attempt to free object(0x%p) outside of slab", - object); - } else if (!slab->slab_cache) { - pr_err("SLUB <none>: no slab for object 0x%p.\n", - object); - dump_stack(); - } else - object_err(s, slab, object, - "page slab pointer corrupt."); - return 0; - } - return 1; -} - -/* - * Parse a block of slub_debug options. Blocks are delimited by ';' - * - * @str: start of block - * @flags: returns parsed flags, or DEBUG_DEFAULT_FLAGS if none specified - * @slabs: return start of list of slabs, or NULL when there's no list - * @init: assume this is initial parsing and not per-kmem-create parsing - * - * returns the start of next block if there's any, or NULL - */ -static char * -parse_slub_debug_flags(char *str, slab_flags_t *flags, char **slabs, bool init) -{ - bool higher_order_disable = false; - - /* Skip any completely empty blocks */ - while (*str && *str == ';') - str++; - - if (*str == ',') { - /* - * No options but restriction on slabs. This means full - * debugging for slabs matching a pattern. - */ - *flags = DEBUG_DEFAULT_FLAGS; - goto check_slabs; - } - *flags = 0; - - /* Determine which debug features should be switched on */ - for (; *str && *str != ',' && *str != ';'; str++) { - switch (tolower(*str)) { - case '-': - *flags = 0; - break; - case 'f': - *flags |= SLAB_CONSISTENCY_CHECKS; - break; - case 'z': - *flags |= SLAB_RED_ZONE; - break; - case 'p': - *flags |= SLAB_POISON; - break; - case 'u': - *flags |= SLAB_STORE_USER; - break; - case 't': - *flags |= SLAB_TRACE; - break; - case 'a': - *flags |= SLAB_FAILSLAB; - break; - case 'o': - /* - * Avoid enabling debugging on caches if its minimum - * order would increase as a result. - */ - higher_order_disable = true; - break; - default: - if (init) - pr_err("slub_debug option '%c' unknown. skipped\n", *str); - } - } -check_slabs: - if (*str == ',') - *slabs = ++str; - else - *slabs = NULL; - - /* Skip over the slab list */ - while (*str && *str != ';') - str++; - - /* Skip any completely empty blocks */ - while (*str && *str == ';') - str++; - - if (init && higher_order_disable) - disable_higher_order_debug = 1; - - if (*str) - return str; - else - return NULL; -} - -static int __init setup_slub_debug(char *str) -{ - slab_flags_t flags; - slab_flags_t global_flags; - char *saved_str; - char *slab_list; - bool global_slub_debug_changed = false; - bool slab_list_specified = false; - - global_flags = DEBUG_DEFAULT_FLAGS; - if (*str++ != '=' || !*str) - /* - * No options specified. Switch on full debugging. - */ - goto out; - - saved_str = str; - while (str) { - str = parse_slub_debug_flags(str, &flags, &slab_list, true); - - if (!slab_list) { - global_flags = flags; - global_slub_debug_changed = true; - } else { - slab_list_specified = true; - if (flags & SLAB_STORE_USER) - stack_depot_request_early_init(); - } - } - - /* - * For backwards compatibility, a single list of flags with list of - * slabs means debugging is only changed for those slabs, so the global - * slub_debug should be unchanged (0 or DEBUG_DEFAULT_FLAGS, depending - * on CONFIG_SLUB_DEBUG_ON). We can extended that to multiple lists as - * long as there is no option specifying flags without a slab list. - */ - if (slab_list_specified) { - if (!global_slub_debug_changed) - global_flags = slub_debug; - slub_debug_string = saved_str; - } -out: - slub_debug = global_flags; - if (slub_debug & SLAB_STORE_USER) - stack_depot_request_early_init(); - if (slub_debug != 0 || slub_debug_string) - static_branch_enable(&slub_debug_enabled); - else - static_branch_disable(&slub_debug_enabled); - if ((static_branch_unlikely(&init_on_alloc) || - static_branch_unlikely(&init_on_free)) && - (slub_debug & SLAB_POISON)) - pr_info("mem auto-init: SLAB_POISON will take precedence over init_on_alloc/init_on_free\n"); - return 1; -} - -__setup("slub_debug", setup_slub_debug); - -/* - * kmem_cache_flags - apply debugging options to the cache - * @object_size: the size of an object without meta data - * @flags: flags to set - * @name: name of the cache - * - * Debug option(s) are applied to @flags. In addition to the debug - * option(s), if a slab name (or multiple) is specified i.e. - * slub_debug=<Debug-Options>,<slab name1>,<slab name2> ... - * then only the select slabs will receive the debug option(s). - */ -slab_flags_t kmem_cache_flags(unsigned int object_size, - slab_flags_t flags, const char *name) -{ - char *iter; - size_t len; - char *next_block; - slab_flags_t block_flags; - slab_flags_t slub_debug_local = slub_debug; - - if (flags & SLAB_NO_USER_FLAGS) - return flags; - - /* - * If the slab cache is for debugging (e.g. kmemleak) then - * don't store user (stack trace) information by default, - * but let the user enable it via the command line below. - */ - if (flags & SLAB_NOLEAKTRACE) - slub_debug_local &= ~SLAB_STORE_USER; - - len = strlen(name); - next_block = slub_debug_string; - /* Go through all blocks of debug options, see if any matches our slab's name */ - while (next_block) { - next_block = parse_slub_debug_flags(next_block, &block_flags, &iter, false); - if (!iter) - continue; - /* Found a block that has a slab list, search it */ - while (*iter) { - char *end, *glob; - size_t cmplen; - - end = strchrnul(iter, ','); - if (next_block && next_block < end) - end = next_block - 1; - - glob = strnchr(iter, end - iter, '*'); - if (glob) - cmplen = glob - iter; - else - cmplen = max_t(size_t, len, (end - iter)); - - if (!strncmp(name, iter, cmplen)) { - flags |= block_flags; - return flags; - } - - if (!*end || *end == ';') - break; - iter = end + 1; - } - } - - return flags | slub_debug_local; -} -#else /* !CONFIG_SLUB_DEBUG */ -static inline void setup_object_debug(struct kmem_cache *s, void *object) {} -static inline -void setup_slab_debug(struct kmem_cache *s, struct slab *slab, void *addr) {} - -static inline bool alloc_debug_processing(struct kmem_cache *s, - struct slab *slab, void *object, int orig_size) { return true; } - -static inline bool free_debug_processing(struct kmem_cache *s, - struct slab *slab, void *head, void *tail, int *bulk_cnt, - unsigned long addr, depot_stack_handle_t handle) { return true; } - -static inline void slab_pad_check(struct kmem_cache *s, struct slab *slab) {} -static inline int check_object(struct kmem_cache *s, struct slab *slab, - void *object, u8 val) { return 1; } -static inline depot_stack_handle_t set_track_prepare(void) { return 0; } -static inline void set_track(struct kmem_cache *s, void *object, - enum track_item alloc, unsigned long addr) {} -static inline void add_full(struct kmem_cache *s, struct kmem_cache_node *n, - struct slab *slab) {} -static inline void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, - struct slab *slab) {} -slab_flags_t kmem_cache_flags(unsigned int object_size, - slab_flags_t flags, const char *name) -{ - return flags; -} -#define slub_debug 0 - -#define disable_higher_order_debug 0 - -static inline unsigned long slabs_node(struct kmem_cache *s, int node) - { return 0; } -static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) - { return 0; } -static inline void inc_slabs_node(struct kmem_cache *s, int node, - int objects) {} -static inline void dec_slabs_node(struct kmem_cache *s, int node, - int objects) {} - -#ifndef CONFIG_SLUB_TINY -static bool freelist_corrupted(struct kmem_cache *s, struct slab *slab, - void **freelist, void *nextfree) -{ - return false; -} -#endif -#endif /* CONFIG_SLUB_DEBUG */ - -/* - * Hooks for other subsystems that check memory allocations. In a typical - * production configuration these hooks all should produce no code at all. - */ -static __always_inline bool slab_free_hook(struct kmem_cache *s, - void *x, bool init) -{ - kmemleak_free_recursive(x, s->flags); - kmsan_slab_free(s, x); - - debug_check_no_locks_freed(x, s->object_size); - - if (!(s->flags & SLAB_DEBUG_OBJECTS)) - debug_check_no_obj_freed(x, s->object_size); - - /* Use KCSAN to help debug racy use-after-free. */ - if (!(s->flags & SLAB_TYPESAFE_BY_RCU)) - __kcsan_check_access(x, s->object_size, - KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ASSERT); - - /* - * As memory initialization might be integrated into KASAN, - * kasan_slab_free and initialization memset's must be - * kept together to avoid discrepancies in behavior. - * - * The initialization memset's clear the object and the metadata, - * but don't touch the SLAB redzone. - */ - if (init) { - int rsize; - - if (!kasan_has_integrated_init()) - memset(kasan_reset_tag(x), 0, s->object_size); - rsize = (s->flags & SLAB_RED_ZONE) ? s->red_left_pad : 0; - memset((char *)kasan_reset_tag(x) + s->inuse, 0, - s->size - s->inuse - rsize); - } - /* KASAN might put x into memory quarantine, delaying its reuse. */ - return kasan_slab_free(s, x, init); -} - -static inline bool slab_free_freelist_hook(struct kmem_cache *s, - void **head, void **tail, - int *cnt) -{ - - void *object; - void *next = *head; - void *old_tail = *tail ? *tail : *head; - - if (is_kfence_address(next)) { - slab_free_hook(s, next, false); - return true; - } - - /* Head and tail of the reconstructed freelist */ - *head = NULL; - *tail = NULL; - - do { - object = next; - next = get_freepointer(s, object); - - /* If object's reuse doesn't have to be delayed */ - if (!slab_free_hook(s, object, slab_want_init_on_free(s))) { - /* Move object to the new freelist */ - set_freepointer(s, object, *head); - *head = object; - if (!*tail) - *tail = object; - } else { - /* - * Adjust the reconstructed freelist depth - * accordingly if object's reuse is delayed. - */ - --(*cnt); - } - } while (object != old_tail); - - if (*head == *tail) - *tail = NULL; - - return *head != NULL; -} - -static void *setup_object(struct kmem_cache *s, void *object) -{ - setup_object_debug(s, object); - object = kasan_init_slab_obj(s, object); - if (unlikely(s->ctor)) { - kasan_unpoison_object_data(s, object); - s->ctor(object); - kasan_poison_object_data(s, object); - } - return object; -} - -/* - * Slab allocation and freeing - */ -static inline struct slab *alloc_slab_page(gfp_t flags, int node, - struct kmem_cache_order_objects oo) -{ - struct folio *folio; - struct slab *slab; - unsigned int order = oo_order(oo); - - if (node == NUMA_NO_NODE) - folio = (struct folio *)alloc_pages(flags, order); - else - folio = (struct folio *)__alloc_pages_node(node, flags, order); - - if (!folio) - return NULL; - - slab = folio_slab(folio); - __folio_set_slab(folio); - /* Make the flag visible before any changes to folio->mapping */ - smp_wmb(); - if (folio_is_pfmemalloc(folio)) - slab_set_pfmemalloc(slab); - - return slab; -} - -#ifdef CONFIG_SLAB_FREELIST_RANDOM -/* Pre-initialize the random sequence cache */ -static int init_cache_random_seq(struct kmem_cache *s) -{ - unsigned int count = oo_objects(s->oo); - int err; - - /* Bailout if already initialised */ - if (s->random_seq) - return 0; - - err = cache_random_seq_create(s, count, GFP_KERNEL); - if (err) { - pr_err("SLUB: Unable to initialize free list for %s\n", - s->name); - return err; - } - - /* Transform to an offset on the set of pages */ - if (s->random_seq) { - unsigned int i; - - for (i = 0; i < count; i++) - s->random_seq[i] *= s->size; - } - return 0; -} - -/* Initialize each random sequence freelist per cache */ -static void __init init_freelist_randomization(void) -{ - struct kmem_cache *s; - - mutex_lock(&slab_mutex); - - list_for_each_entry(s, &slab_caches, list) - init_cache_random_seq(s); - - mutex_unlock(&slab_mutex); -} - -/* Get the next entry on the pre-computed freelist randomized */ -static void *next_freelist_entry(struct kmem_cache *s, struct slab *slab, - unsigned long *pos, void *start, - unsigned long page_limit, - unsigned long freelist_count) -{ - unsigned int idx; - - /* - * If the target page allocation failed, the number of objects on the - * page might be smaller than the usual size defined by the cache. - */ - do { - idx = s->random_seq[*pos]; - *pos += 1; - if (*pos >= freelist_count) - *pos = 0; - } while (unlikely(idx >= page_limit)); - - return (char *)start + idx; -} - -/* Shuffle the single linked freelist based on a random pre-computed sequence */ -static bool shuffle_freelist(struct kmem_cache *s, struct slab *slab) -{ - void *start; - void *cur; - void *next; - unsigned long idx, pos, page_limit, freelist_count; - - if (slab->objects < 2 || !s->random_seq) - return false; - - freelist_count = oo_objects(s->oo); - pos = get_random_u32_below(freelist_count); - - page_limit = slab->objects * s->size; - start = fixup_red_left(s, slab_address(slab)); - - /* First entry is used as the base of the freelist */ - cur = next_freelist_entry(s, slab, &pos, start, page_limit, - freelist_count); - cur = setup_object(s, cur); - slab->freelist = cur; - - for (idx = 1; idx < slab->objects; idx++) { - next = next_freelist_entry(s, slab, &pos, start, page_limit, - freelist_count); - next = setup_object(s, next); - set_freepointer(s, cur, next); - cur = next; - } - set_freepointer(s, cur, NULL); - - return true; -} -#else -static inline int init_cache_random_seq(struct kmem_cache *s) -{ - return 0; -} -static inline void init_freelist_randomization(void) { } -static inline bool shuffle_freelist(struct kmem_cache *s, struct slab *slab) -{ - return false; -} -#endif /* CONFIG_SLAB_FREELIST_RANDOM */ - -static struct slab *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) -{ - struct slab *slab; - struct kmem_cache_order_objects oo = s->oo; - gfp_t alloc_gfp; - void *start, *p, *next; - int idx; - bool shuffle; - - flags &= gfp_allowed_mask; - - flags |= s->allocflags; - - /* - * Let the initial higher-order allocation fail under memory pressure - * so we fall-back to the minimum order allocation. - */ - alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL; - if ((alloc_gfp & __GFP_DIRECT_RECLAIM) && oo_order(oo) > oo_order(s->min)) - alloc_gfp = (alloc_gfp | __GFP_NOMEMALLOC) & ~__GFP_RECLAIM; - - slab = alloc_slab_page(alloc_gfp, node, oo); - if (unlikely(!slab)) { - oo = s->min; - alloc_gfp = flags; - /* - * Allocation may have failed due to fragmentation. - * Try a lower order alloc if possible - */ - slab = alloc_slab_page(alloc_gfp, node, oo); - if (unlikely(!slab)) - return NULL; - stat(s, ORDER_FALLBACK); - } - - slab->objects = oo_objects(oo); - slab->inuse = 0; - slab->frozen = 0; - - account_slab(slab, oo_order(oo), s, flags); - - slab->slab_cache = s; - - kasan_poison_slab(slab); - - start = slab_address(slab); - - setup_slab_debug(s, slab, start); - - shuffle = shuffle_freelist(s, slab); - - if (!shuffle) { - start = fixup_red_left(s, start); - start = setup_object(s, start); - slab->freelist = start; - for (idx = 0, p = start; idx < slab->objects - 1; idx++) { - next = p + s->size; - next = setup_object(s, next); - set_freepointer(s, p, next); - p = next; - } - set_freepointer(s, p, NULL); - } - - return slab; -} - -static struct slab *new_slab(struct kmem_cache *s, gfp_t flags, int node) -{ - if (unlikely(flags & GFP_SLAB_BUG_MASK)) - flags = kmalloc_fix_flags(flags); - - WARN_ON_ONCE(s->ctor && (flags & __GFP_ZERO)); - - return allocate_slab(s, - flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node); -} - -static void __free_slab(struct kmem_cache *s, struct slab *slab) -{ - struct folio *folio = slab_folio(slab); - int order = folio_order(folio); - int pages = 1 << order; - - __slab_clear_pfmemalloc(slab); - folio->mapping = NULL; - /* Make the mapping reset visible before clearing the flag */ - smp_wmb(); - __folio_clear_slab(folio); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += pages; - unaccount_slab(slab, order, s); - __free_pages(&folio->page, order); -} - -static void rcu_free_slab(struct rcu_head *h) -{ - struct slab *slab = container_of(h, struct slab, rcu_head); - - __free_slab(slab->slab_cache, slab); -} - -static void free_slab(struct kmem_cache *s, struct slab *slab) -{ - if (kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) { - void *p; - - slab_pad_check(s, slab); - for_each_object(p, s, slab_address(slab), slab->objects) - check_object(s, slab, p, SLUB_RED_INACTIVE); - } - - if (unlikely(s->flags & SLAB_TYPESAFE_BY_RCU)) - call_rcu(&slab->rcu_head, rcu_free_slab); - else - __free_slab(s, slab); -} - -static void discard_slab(struct kmem_cache *s, struct slab *slab) -{ - dec_slabs_node(s, slab_nid(slab), slab->objects); - free_slab(s, slab); -} - -/* - * Management of partially allocated slabs. - */ -static inline void -__add_partial(struct kmem_cache_node *n, struct slab *slab, int tail) -{ - n->nr_partial++; - if (tail == DEACTIVATE_TO_TAIL) - list_add_tail(&slab->slab_list, &n->partial); - else - list_add(&slab->slab_list, &n->partial); -} - -static inline void add_partial(struct kmem_cache_node *n, - struct slab *slab, int tail) -{ - lockdep_assert_held(&n->list_lock); - __add_partial(n, slab, tail); -} - -static inline void remove_partial(struct kmem_cache_node *n, - struct slab *slab) -{ - lockdep_assert_held(&n->list_lock); - list_del(&slab->slab_list); - n->nr_partial--; -} - -/* - * Called only for kmem_cache_debug() caches instead of acquire_slab(), with a - * slab from the n->partial list. Remove only a single object from the slab, do - * the alloc_debug_processing() checks and leave the slab on the list, or move - * it to full list if it was the last free object. - */ -static void *alloc_single_from_partial(struct kmem_cache *s, - struct kmem_cache_node *n, struct slab *slab, int orig_size) -{ - void *object; - - lockdep_assert_held(&n->list_lock); - - object = slab->freelist; - slab->freelist = get_freepointer(s, object); - slab->inuse++; - - if (!alloc_debug_processing(s, slab, object, orig_size)) { - remove_partial(n, slab); - return NULL; - } - - if (slab->inuse == slab->objects) { - remove_partial(n, slab); - add_full(s, n, slab); - } - - return object; -} - -/* - * Called only for kmem_cache_debug() caches to allocate from a freshly - * allocated slab. Allocate a single object instead of whole freelist - * and put the slab to the partial (or full) list. - */ -static void *alloc_single_from_new_slab(struct kmem_cache *s, - struct slab *slab, int orig_size) -{ - int nid = slab_nid(slab); - struct kmem_cache_node *n = get_node(s, nid); - unsigned long flags; - void *object; - - - object = slab->freelist; - slab->freelist = get_freepointer(s, object); - slab->inuse = 1; - - if (!alloc_debug_processing(s, slab, object, orig_size)) - /* - * It's not really expected that this would fail on a - * freshly allocated slab, but a concurrent memory - * corruption in theory could cause that. - */ - return NULL; - - spin_lock_irqsave(&n->list_lock, flags); - - if (slab->inuse == slab->objects) - add_full(s, n, slab); - else - add_partial(n, slab, DEACTIVATE_TO_HEAD); - - inc_slabs_node(s, nid, slab->objects); - spin_unlock_irqrestore(&n->list_lock, flags); - - return object; -} - -/* - * Remove slab from the partial list, freeze it and - * return the pointer to the freelist. - * - * Returns a list of objects or NULL if it fails. - */ -static inline void *acquire_slab(struct kmem_cache *s, - struct kmem_cache_node *n, struct slab *slab, - int mode) -{ - void *freelist; - unsigned long counters; - struct slab new; - - lockdep_assert_held(&n->list_lock); - - /* - * Zap the freelist and set the frozen bit. - * The old freelist is the list of objects for the - * per cpu allocation list. - */ - freelist = slab->freelist; - counters = slab->counters; - new.counters = counters; - if (mode) { - new.inuse = slab->objects; - new.freelist = NULL; - } else { - new.freelist = freelist; - } - - VM_BUG_ON(new.frozen); - new.frozen = 1; - - if (!__cmpxchg_double_slab(s, slab, - freelist, counters, - new.freelist, new.counters, - "acquire_slab")) - return NULL; - - remove_partial(n, slab); - WARN_ON(!freelist); - return freelist; -} - -#ifdef CONFIG_SLUB_CPU_PARTIAL -static void put_cpu_partial(struct kmem_cache *s, struct slab *slab, int drain); -#else -static inline void put_cpu_partial(struct kmem_cache *s, struct slab *slab, - int drain) { } -#endif -static inline bool pfmemalloc_match(struct slab *slab, gfp_t gfpflags); - -/* - * Try to allocate a partial slab from a specific node. - */ -static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n, - struct partial_context *pc) -{ - struct slab *slab, *slab2; - void *object = NULL; - unsigned long flags; - unsigned int partial_slabs = 0; - - /* - * Racy check. If we mistakenly see no partial slabs then we - * just allocate an empty slab. If we mistakenly try to get a - * partial slab and there is none available then get_partial() - * will return NULL. - */ - if (!n || !n->nr_partial) - return NULL; - - spin_lock_irqsave(&n->list_lock, flags); - list_for_each_entry_safe(slab, slab2, &n->partial, slab_list) { - void *t; - - if (!pfmemalloc_match(slab, pc->flags)) - continue; - - if (IS_ENABLED(CONFIG_SLUB_TINY) || kmem_cache_debug(s)) { - object = alloc_single_from_partial(s, n, slab, - pc->orig_size); - if (object) - break; - continue; - } - - t = acquire_slab(s, n, slab, object == NULL); - if (!t) - break; - - if (!object) { - *pc->slab = slab; - stat(s, ALLOC_FROM_PARTIAL); - object = t; - } else { - put_cpu_partial(s, slab, 0); - stat(s, CPU_PARTIAL_NODE); - partial_slabs++; - } -#ifdef CONFIG_SLUB_CPU_PARTIAL - if (!kmem_cache_has_cpu_partial(s) - || partial_slabs > s->cpu_partial_slabs / 2) - break; -#else - break; -#endif - - } - spin_unlock_irqrestore(&n->list_lock, flags); - return object; -} - -/* - * Get a slab from somewhere. Search in increasing NUMA distances. - */ -static void *get_any_partial(struct kmem_cache *s, struct partial_context *pc) -{ -#ifdef CONFIG_NUMA - struct zonelist *zonelist; - struct zoneref *z; - struct zone *zone; - enum zone_type highest_zoneidx = gfp_zone(pc->flags); - void *object; - unsigned int cpuset_mems_cookie; - - /* - * The defrag ratio allows a configuration of the tradeoffs between - * inter node defragmentation and node local allocations. A lower - * defrag_ratio increases the tendency to do local allocations - * instead of attempting to obtain partial slabs from other nodes. - * - * If the defrag_ratio is set to 0 then kmalloc() always - * returns node local objects. If the ratio is higher then kmalloc() - * may return off node objects because partial slabs are obtained - * from other nodes and filled up. - * - * If /sys/kernel/slab/xx/remote_node_defrag_ratio is set to 100 - * (which makes defrag_ratio = 1000) then every (well almost) - * allocation will first attempt to defrag slab caches on other nodes. - * This means scanning over all nodes to look for partial slabs which - * may be expensive if we do it every time we are trying to find a slab - * with available objects. - */ - if (!s->remote_node_defrag_ratio || - get_cycles() % 1024 > s->remote_node_defrag_ratio) - return NULL; - - do { - cpuset_mems_cookie = read_mems_allowed_begin(); - zonelist = node_zonelist(mempolicy_slab_node(), pc->flags); - for_each_zone_zonelist(zone, z, zonelist, highest_zoneidx) { - struct kmem_cache_node *n; - - n = get_node(s, zone_to_nid(zone)); - - if (n && cpuset_zone_allowed(zone, pc->flags) && - n->nr_partial > s->min_partial) { - object = get_partial_node(s, n, pc); - if (object) { - /* - * Don't check read_mems_allowed_retry() - * here - if mems_allowed was updated in - * parallel, that was a harmless race - * between allocation and the cpuset - * update - */ - return object; - } - } - } - } while (read_mems_allowed_retry(cpuset_mems_cookie)); -#endif /* CONFIG_NUMA */ - return NULL; -} - -/* - * Get a partial slab, lock it and return it. - */ -static void *get_partial(struct kmem_cache *s, int node, struct partial_context *pc) -{ - void *object; - int searchnode = node; - - if (node == NUMA_NO_NODE) - searchnode = numa_mem_id(); - - object = get_partial_node(s, get_node(s, searchnode), pc); - if (object || node != NUMA_NO_NODE) - return object; - - return get_any_partial(s, pc); -} - -#ifndef CONFIG_SLUB_TINY - -#ifdef CONFIG_PREEMPTION -/* - * Calculate the next globally unique transaction for disambiguation - * during cmpxchg. The transactions start with the cpu number and are then - * incremented by CONFIG_NR_CPUS. - */ -#define TID_STEP roundup_pow_of_two(CONFIG_NR_CPUS) -#else -/* - * No preemption supported therefore also no need to check for - * different cpus. - */ -#define TID_STEP 1 -#endif /* CONFIG_PREEMPTION */ - -static inline unsigned long next_tid(unsigned long tid) -{ - return tid + TID_STEP; -} - -#ifdef SLUB_DEBUG_CMPXCHG -static inline unsigned int tid_to_cpu(unsigned long tid) -{ - return tid % TID_STEP; -} - -static inline unsigned long tid_to_event(unsigned long tid) -{ - return tid / TID_STEP; -} -#endif - -static inline unsigned int init_tid(int cpu) -{ - return cpu; -} - -static inline void note_cmpxchg_failure(const char *n, - const struct kmem_cache *s, unsigned long tid) -{ -#ifdef SLUB_DEBUG_CMPXCHG - unsigned long actual_tid = __this_cpu_read(s->cpu_slab->tid); - - pr_info("%s %s: cmpxchg redo ", n, s->name); - -#ifdef CONFIG_PREEMPTION - if (tid_to_cpu(tid) != tid_to_cpu(actual_tid)) - pr_warn("due to cpu change %d -> %d\n", - tid_to_cpu(tid), tid_to_cpu(actual_tid)); - else -#endif - if (tid_to_event(tid) != tid_to_event(actual_tid)) - pr_warn("due to cpu running other code. Event %ld->%ld\n", - tid_to_event(tid), tid_to_event(actual_tid)); - else - pr_warn("for unknown reason: actual=%lx was=%lx target=%lx\n", - actual_tid, tid, next_tid(tid)); -#endif - stat(s, CMPXCHG_DOUBLE_CPU_FAIL); -} - -static void init_kmem_cache_cpus(struct kmem_cache *s) -{ - int cpu; - struct kmem_cache_cpu *c; - - for_each_possible_cpu(cpu) { - c = per_cpu_ptr(s->cpu_slab, cpu); - local_lock_init(&c->lock); - c->tid = init_tid(cpu); - } -} - -/* - * Finishes removing the cpu slab. Merges cpu's freelist with slab's freelist, - * unfreezes the slabs and puts it on the proper list. - * Assumes the slab has been already safely taken away from kmem_cache_cpu - * by the caller. - */ -static void deactivate_slab(struct kmem_cache *s, struct slab *slab, - void *freelist) -{ - enum slab_modes { M_NONE, M_PARTIAL, M_FREE, M_FULL_NOLIST }; - struct kmem_cache_node *n = get_node(s, slab_nid(slab)); - int free_delta = 0; - enum slab_modes mode = M_NONE; - void *nextfree, *freelist_iter, *freelist_tail; - int tail = DEACTIVATE_TO_HEAD; - unsigned long flags = 0; - struct slab new; - struct slab old; - - if (slab->freelist) { - stat(s, DEACTIVATE_REMOTE_FREES); - tail = DEACTIVATE_TO_TAIL; - } - - /* - * Stage one: Count the objects on cpu's freelist as free_delta and - * remember the last object in freelist_tail for later splicing. - */ - freelist_tail = NULL; - freelist_iter = freelist; - while (freelist_iter) { - nextfree = get_freepointer(s, freelist_iter); - - /* - * If 'nextfree' is invalid, it is possible that the object at - * 'freelist_iter' is already corrupted. So isolate all objects - * starting at 'freelist_iter' by skipping them. - */ - if (freelist_corrupted(s, slab, &freelist_iter, nextfree)) - break; - - freelist_tail = freelist_iter; - free_delta++; - - freelist_iter = nextfree; - } - - /* - * Stage two: Unfreeze the slab while splicing the per-cpu - * freelist to the head of slab's freelist. - * - * Ensure that the slab is unfrozen while the list presence - * reflects the actual number of objects during unfreeze. - * - * We first perform cmpxchg holding lock and insert to list - * when it succeed. If there is mismatch then the slab is not - * unfrozen and number of objects in the slab may have changed. - * Then release lock and retry cmpxchg again. - */ -redo: - - old.freelist = READ_ONCE(slab->freelist); - old.counters = READ_ONCE(slab->counters); - VM_BUG_ON(!old.frozen); - - /* Determine target state of the slab */ - new.counters = old.counters; - if (freelist_tail) { - new.inuse -= free_delta; - set_freepointer(s, freelist_tail, old.freelist); - new.freelist = freelist; - } else - new.freelist = old.freelist; - - new.frozen = 0; - - if (!new.inuse && n->nr_partial >= s->min_partial) { - mode = M_FREE; - } else if (new.freelist) { - mode = M_PARTIAL; - /* - * Taking the spinlock removes the possibility that - * acquire_slab() will see a slab that is frozen - */ - spin_lock_irqsave(&n->list_lock, flags); - } else { - mode = M_FULL_NOLIST; - } - - - if (!cmpxchg_double_slab(s, slab, - old.freelist, old.counters, - new.freelist, new.counters, - "unfreezing slab")) { - if (mode == M_PARTIAL) - spin_unlock_irqrestore(&n->list_lock, flags); - goto redo; - } - - - if (mode == M_PARTIAL) { - add_partial(n, slab, tail); - spin_unlock_irqrestore(&n->list_lock, flags); - stat(s, tail); - } else if (mode == M_FREE) { - stat(s, DEACTIVATE_EMPTY); - discard_slab(s, slab); - stat(s, FREE_SLAB); - } else if (mode == M_FULL_NOLIST) { - stat(s, DEACTIVATE_FULL); - } -} - -#ifdef CONFIG_SLUB_CPU_PARTIAL -static void __unfreeze_partials(struct kmem_cache *s, struct slab *partial_slab) -{ - struct kmem_cache_node *n = NULL, *n2 = NULL; - struct slab *slab, *slab_to_discard = NULL; - unsigned long flags = 0; - - while (partial_slab) { - struct slab new; - struct slab old; - - slab = partial_slab; - partial_slab = slab->next; - - n2 = get_node(s, slab_nid(slab)); - if (n != n2) { - if (n) - spin_unlock_irqrestore(&n->list_lock, flags); - - n = n2; - spin_lock_irqsave(&n->list_lock, flags); - } - - do { - - old.freelist = slab->freelist; - old.counters = slab->counters; - VM_BUG_ON(!old.frozen); - - new.counters = old.counters; - new.freelist = old.freelist; - - new.frozen = 0; - - } while (!__cmpxchg_double_slab(s, slab, - old.freelist, old.counters, - new.freelist, new.counters, - "unfreezing slab")); - - if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) { - slab->next = slab_to_discard; - slab_to_discard = slab; - } else { - add_partial(n, slab, DEACTIVATE_TO_TAIL); - stat(s, FREE_ADD_PARTIAL); - } - } - - if (n) - spin_unlock_irqrestore(&n->list_lock, flags); - - while (slab_to_discard) { - slab = slab_to_discard; - slab_to_discard = slab_to_discard->next; - - stat(s, DEACTIVATE_EMPTY); - discard_slab(s, slab); - stat(s, FREE_SLAB); - } -} - -/* - * Unfreeze all the cpu partial slabs. - */ -static void unfreeze_partials(struct kmem_cache *s) -{ - struct slab *partial_slab; - unsigned long flags; - - local_lock_irqsave(&s->cpu_slab->lock, flags); - partial_slab = this_cpu_read(s->cpu_slab->partial); - this_cpu_write(s->cpu_slab->partial, NULL); - local_unlock_irqrestore(&s->cpu_slab->lock, flags); - - if (partial_slab) - __unfreeze_partials(s, partial_slab); -} - -static void unfreeze_partials_cpu(struct kmem_cache *s, - struct kmem_cache_cpu *c) -{ - struct slab *partial_slab; - - partial_slab = slub_percpu_partial(c); - c->partial = NULL; - - if (partial_slab) - __unfreeze_partials(s, partial_slab); -} - -/* - * Put a slab that was just frozen (in __slab_free|get_partial_node) into a - * partial slab slot if available. - * - * If we did not find a slot then simply move all the partials to the - * per node partial list. - */ -static void put_cpu_partial(struct kmem_cache *s, struct slab *slab, int drain) -{ - struct slab *oldslab; - struct slab *slab_to_unfreeze = NULL; - unsigned long flags; - int slabs = 0; - - local_lock_irqsave(&s->cpu_slab->lock, flags); - - oldslab = this_cpu_read(s->cpu_slab->partial); - - if (oldslab) { - if (drain && oldslab->slabs >= s->cpu_partial_slabs) { - /* - * Partial array is full. Move the existing set to the - * per node partial list. Postpone the actual unfreezing - * outside of the critical section. - */ - slab_to_unfreeze = oldslab; - oldslab = NULL; - } else { - slabs = oldslab->slabs; - } - } - - slabs++; - - slab->slabs = slabs; - slab->next = oldslab; - - this_cpu_write(s->cpu_slab->partial, slab); - - local_unlock_irqrestore(&s->cpu_slab->lock, flags); - - if (slab_to_unfreeze) { - __unfreeze_partials(s, slab_to_unfreeze); - stat(s, CPU_PARTIAL_DRAIN); - } -} - -#else /* CONFIG_SLUB_CPU_PARTIAL */ - -static inline void unfreeze_partials(struct kmem_cache *s) { } -static inline void unfreeze_partials_cpu(struct kmem_cache *s, - struct kmem_cache_cpu *c) { } - -#endif /* CONFIG_SLUB_CPU_PARTIAL */ - -static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) -{ - unsigned long flags; - struct slab *slab; - void *freelist; - - local_lock_irqsave(&s->cpu_slab->lock, flags); - - slab = c->slab; - freelist = c->freelist; - - c->slab = NULL; - c->freelist = NULL; - c->tid = next_tid(c->tid); - - local_unlock_irqrestore(&s->cpu_slab->lock, flags); - - if (slab) { - deactivate_slab(s, slab, freelist); - stat(s, CPUSLAB_FLUSH); - } -} - -static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) -{ - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); - void *freelist = c->freelist; - struct slab *slab = c->slab; - - c->slab = NULL; - c->freelist = NULL; - c->tid = next_tid(c->tid); - - if (slab) { - deactivate_slab(s, slab, freelist); - stat(s, CPUSLAB_FLUSH); - } - - unfreeze_partials_cpu(s, c); -} - -struct slub_flush_work { - struct work_struct work; - struct kmem_cache *s; - bool skip; -}; - -/* - * Flush cpu slab. - * - * Called from CPU work handler with migration disabled. - */ -static void flush_cpu_slab(struct work_struct *w) -{ - struct kmem_cache *s; - struct kmem_cache_cpu *c; - struct slub_flush_work *sfw; - - sfw = container_of(w, struct slub_flush_work, work); - - s = sfw->s; - c = this_cpu_ptr(s->cpu_slab); - - if (c->slab) - flush_slab(s, c); - - unfreeze_partials(s); -} - -static bool has_cpu_slab(int cpu, struct kmem_cache *s) -{ - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); - - return c->slab || slub_percpu_partial(c); -} - -static DEFINE_MUTEX(flush_lock); -static DEFINE_PER_CPU(struct slub_flush_work, slub_flush); - -static void flush_all_cpus_locked(struct kmem_cache *s) -{ - struct slub_flush_work *sfw; - unsigned int cpu; - - lockdep_assert_cpus_held(); - mutex_lock(&flush_lock); - - for_each_online_cpu(cpu) { - sfw = &per_cpu(slub_flush, cpu); - if (!has_cpu_slab(cpu, s)) { - sfw->skip = true; - continue; - } - INIT_WORK(&sfw->work, flush_cpu_slab); - sfw->skip = false; - sfw->s = s; - queue_work_on(cpu, flushwq, &sfw->work); - } - - for_each_online_cpu(cpu) { - sfw = &per_cpu(slub_flush, cpu); - if (sfw->skip) - continue; - flush_work(&sfw->work); - } - - mutex_unlock(&flush_lock); -} - -static void flush_all(struct kmem_cache *s) -{ - cpus_read_lock(); - flush_all_cpus_locked(s); - cpus_read_unlock(); -} - -/* - * Use the cpu notifier to insure that the cpu slabs are flushed when - * necessary. - */ -static int slub_cpu_dead(unsigned int cpu) -{ - struct kmem_cache *s; - - mutex_lock(&slab_mutex); - list_for_each_entry(s, &slab_caches, list) - __flush_cpu_slab(s, cpu); - mutex_unlock(&slab_mutex); - return 0; -} - -#else /* CONFIG_SLUB_TINY */ -static inline void flush_all_cpus_locked(struct kmem_cache *s) { } -static inline void flush_all(struct kmem_cache *s) { } -static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) { } -static inline int slub_cpu_dead(unsigned int cpu) { return 0; } -#endif /* CONFIG_SLUB_TINY */ - -/* - * Check if the objects in a per cpu structure fit numa - * locality expectations. - */ -static inline int node_match(struct slab *slab, int node) -{ -#ifdef CONFIG_NUMA - if (node != NUMA_NO_NODE && slab_nid(slab) != node) - return 0; -#endif - return 1; -} - -#ifdef CONFIG_SLUB_DEBUG -static int count_free(struct slab *slab) -{ - return slab->objects - slab->inuse; -} - -static inline unsigned long node_nr_objs(struct kmem_cache_node *n) -{ - return atomic_long_read(&n->total_objects); -} - -/* Supports checking bulk free of a constructed freelist */ -static inline bool free_debug_processing(struct kmem_cache *s, - struct slab *slab, void *head, void *tail, int *bulk_cnt, - unsigned long addr, depot_stack_handle_t handle) -{ - bool checks_ok = false; - void *object = head; - int cnt = 0; - - if (s->flags & SLAB_CONSISTENCY_CHECKS) { - if (!check_slab(s, slab)) - goto out; - } - - if (slab->inuse < *bulk_cnt) { - slab_err(s, slab, "Slab has %d allocated objects but %d are to be freed\n", - slab->inuse, *bulk_cnt); - goto out; - } - -next_object: - - if (++cnt > *bulk_cnt) - goto out_cnt; - - if (s->flags & SLAB_CONSISTENCY_CHECKS) { - if (!free_consistency_checks(s, slab, object, addr)) - goto out; - } - - if (s->flags & SLAB_STORE_USER) - set_track_update(s, object, TRACK_FREE, addr, handle); - trace(s, slab, object, 0); - /* Freepointer not overwritten by init_object(), SLAB_POISON moved it */ - init_object(s, object, SLUB_RED_INACTIVE); - - /* Reached end of constructed freelist yet? */ - if (object != tail) { - object = get_freepointer(s, object); - goto next_object; - } - checks_ok = true; - -out_cnt: - if (cnt != *bulk_cnt) { - slab_err(s, slab, "Bulk free expected %d objects but found %d\n", - *bulk_cnt, cnt); - *bulk_cnt = cnt; - } - -out: - - if (!checks_ok) - slab_fix(s, "Object at 0x%p not freed", object); - - return checks_ok; -} -#endif /* CONFIG_SLUB_DEBUG */ - -#if defined(CONFIG_SLUB_DEBUG) || defined(SLAB_SUPPORTS_SYSFS) -static unsigned long count_partial(struct kmem_cache_node *n, - int (*get_count)(struct slab *)) -{ - unsigned long flags; - unsigned long x = 0; - struct slab *slab; - - spin_lock_irqsave(&n->list_lock, flags); - list_for_each_entry(slab, &n->partial, slab_list) - x += get_count(slab); - spin_unlock_irqrestore(&n->list_lock, flags); - return x; -} -#endif /* CONFIG_SLUB_DEBUG || SLAB_SUPPORTS_SYSFS */ - -#ifdef CONFIG_SLUB_DEBUG -static noinline void -slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) -{ - static DEFINE_RATELIMIT_STATE(slub_oom_rs, DEFAULT_RATELIMIT_INTERVAL, - DEFAULT_RATELIMIT_BURST); - int node; - struct kmem_cache_node *n; - - if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slub_oom_rs)) - return; - - pr_warn("SLUB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", - nid, gfpflags, &gfpflags); - pr_warn(" cache: %s, object size: %u, buffer size: %u, default order: %u, min order: %u\n", - s->name, s->object_size, s->size, oo_order(s->oo), - oo_order(s->min)); - - if (oo_order(s->min) > get_order(s->object_size)) - pr_warn(" %s debugging increased min order, use slub_debug=O to disable.\n", - s->name); - - for_each_kmem_cache_node(s, node, n) { - unsigned long nr_slabs; - unsigned long nr_objs; - unsigned long nr_free; - - nr_free = count_partial(n, count_free); - nr_slabs = node_nr_slabs(n); - nr_objs = node_nr_objs(n); - - pr_warn(" node %d: slabs: %ld, objs: %ld, free: %ld\n", - node, nr_slabs, nr_objs, nr_free); - } -} -#else /* CONFIG_SLUB_DEBUG */ -static inline void -slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) { } -#endif - -static inline bool pfmemalloc_match(struct slab *slab, gfp_t gfpflags) -{ - if (unlikely(slab_test_pfmemalloc(slab))) - return gfp_pfmemalloc_allowed(gfpflags); - - return true; -} - -#ifndef CONFIG_SLUB_TINY -/* - * Check the slab->freelist and either transfer the freelist to the - * per cpu freelist or deactivate the slab. - * - * The slab is still frozen if the return value is not NULL. - * - * If this function returns NULL then the slab has been unfrozen. - */ -static inline void *get_freelist(struct kmem_cache *s, struct slab *slab) -{ - struct slab new; - unsigned long counters; - void *freelist; - - lockdep_assert_held(this_cpu_ptr(&s->cpu_slab->lock)); - - do { - freelist = slab->freelist; - counters = slab->counters; - - new.counters = counters; - VM_BUG_ON(!new.frozen); - - new.inuse = slab->objects; - new.frozen = freelist != NULL; - - } while (!__cmpxchg_double_slab(s, slab, - freelist, counters, - NULL, new.counters, - "get_freelist")); - - return freelist; -} - -/* - * Slow path. The lockless freelist is empty or we need to perform - * debugging duties. - * - * Processing is still very fast if new objects have been freed to the - * regular freelist. In that case we simply take over the regular freelist - * as the lockless freelist and zap the regular freelist. - * - * If that is not working then we fall back to the partial lists. We take the - * first element of the freelist as the object to allocate now and move the - * rest of the freelist to the lockless freelist. - * - * And if we were unable to get a new slab from the partial slab lists then - * we need to allocate a new slab. This is the slowest path since it involves - * a call to the page allocator and the setup of a new slab. - * - * Version of __slab_alloc to use when we know that preemption is - * already disabled (which is the case for bulk allocation). - */ -static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, - unsigned long addr, struct kmem_cache_cpu *c, unsigned int orig_size) -{ - void *freelist; - struct slab *slab; - unsigned long flags; - struct partial_context pc; - - stat(s, ALLOC_SLOWPATH); - -reread_slab: - - slab = READ_ONCE(c->slab); - if (!slab) { - /* - * if the node is not online or has no normal memory, just - * ignore the node constraint - */ - if (unlikely(node != NUMA_NO_NODE && - !node_isset(node, slab_nodes))) - node = NUMA_NO_NODE; - goto new_slab; - } -redo: - - if (unlikely(!node_match(slab, node))) { - /* - * same as above but node_match() being false already - * implies node != NUMA_NO_NODE - */ - if (!node_isset(node, slab_nodes)) { - node = NUMA_NO_NODE; - } else { - stat(s, ALLOC_NODE_MISMATCH); - goto deactivate_slab; - } - } - - /* - * By rights, we should be searching for a slab page that was - * PFMEMALLOC but right now, we are losing the pfmemalloc - * information when the page leaves the per-cpu allocator - */ - if (unlikely(!pfmemalloc_match(slab, gfpflags))) - goto deactivate_slab; - - /* must check again c->slab in case we got preempted and it changed */ - local_lock_irqsave(&s->cpu_slab->lock, flags); - if (unlikely(slab != c->slab)) { - local_unlock_irqrestore(&s->cpu_slab->lock, flags); - goto reread_slab; - } - freelist = c->freelist; - if (freelist) - goto load_freelist; - - freelist = get_freelist(s, slab); - - if (!freelist) { - c->slab = NULL; - c->tid = next_tid(c->tid); - local_unlock_irqrestore(&s->cpu_slab->lock, flags); - stat(s, DEACTIVATE_BYPASS); - goto new_slab; - } - - stat(s, ALLOC_REFILL); - -load_freelist: - - lockdep_assert_held(this_cpu_ptr(&s->cpu_slab->lock)); - - /* - * freelist is pointing to the list of objects to be used. - * slab is pointing to the slab from which the objects are obtained. - * That slab must be frozen for per cpu allocations to work. - */ - VM_BUG_ON(!c->slab->frozen); - c->freelist = get_freepointer(s, freelist); - c->tid = next_tid(c->tid); - local_unlock_irqrestore(&s->cpu_slab->lock, flags); - return freelist; - -deactivate_slab: - - local_lock_irqsave(&s->cpu_slab->lock, flags); - if (slab != c->slab) { - local_unlock_irqrestore(&s->cpu_slab->lock, flags); - goto reread_slab; - } - freelist = c->freelist; - c->slab = NULL; - c->freelist = NULL; - c->tid = next_tid(c->tid); - local_unlock_irqrestore(&s->cpu_slab->lock, flags); - deactivate_slab(s, slab, freelist); - -new_slab: - - if (slub_percpu_partial(c)) { - local_lock_irqsave(&s->cpu_slab->lock, flags); - if (unlikely(c->slab)) { - local_unlock_irqrestore(&s->cpu_slab->lock, flags); - goto reread_slab; - } - if (unlikely(!slub_percpu_partial(c))) { - local_unlock_irqrestore(&s->cpu_slab->lock, flags); - /* we were preempted and partial list got empty */ - goto new_objects; - } - - slab = c->slab = slub_percpu_partial(c); - slub_set_percpu_partial(c, slab); - local_unlock_irqrestore(&s->cpu_slab->lock, flags); - stat(s, CPU_PARTIAL_ALLOC); - goto redo; - } - -new_objects: - - pc.flags = gfpflags; - pc.slab = &slab; - pc.orig_size = orig_size; - freelist = get_partial(s, node, &pc); - if (freelist) - goto check_new_slab; - - slub_put_cpu_ptr(s->cpu_slab); - slab = new_slab(s, gfpflags, node); - c = slub_get_cpu_ptr(s->cpu_slab); - - if (unlikely(!slab)) { - slab_out_of_memory(s, gfpflags, node); - return NULL; - } - - stat(s, ALLOC_SLAB); - - if (kmem_cache_debug(s)) { - freelist = alloc_single_from_new_slab(s, slab, orig_size); - - if (unlikely(!freelist)) - goto new_objects; - - if (s->flags & SLAB_STORE_USER) - set_track(s, freelist, TRACK_ALLOC, addr); - - return freelist; - } - - /* - * No other reference to the slab yet so we can - * muck around with it freely without cmpxchg - */ - freelist = slab->freelist; - slab->freelist = NULL; - slab->inuse = slab->objects; - slab->frozen = 1; - - inc_slabs_node(s, slab_nid(slab), slab->objects); - -check_new_slab: - - if (kmem_cache_debug(s)) { - /* - * For debug caches here we had to go through - * alloc_single_from_partial() so just store the tracking info - * and return the object - */ - if (s->flags & SLAB_STORE_USER) - set_track(s, freelist, TRACK_ALLOC, addr); - - return freelist; - } - - if (unlikely(!pfmemalloc_match(slab, gfpflags))) { - /* - * For !pfmemalloc_match() case we don't load freelist so that - * we don't make further mismatched allocations easier. - */ - deactivate_slab(s, slab, get_freepointer(s, freelist)); - return freelist; - } - -retry_load_slab: - - local_lock_irqsave(&s->cpu_slab->lock, flags); - if (unlikely(c->slab)) { - void *flush_freelist = c->freelist; - struct slab *flush_slab = c->slab; - - c->slab = NULL; - c->freelist = NULL; - c->tid = next_tid(c->tid); - - local_unlock_irqrestore(&s->cpu_slab->lock, flags); - - deactivate_slab(s, flush_slab, flush_freelist); - - stat(s, CPUSLAB_FLUSH); - - goto retry_load_slab; - } - c->slab = slab; - - goto load_freelist; -} - -/* - * A wrapper for ___slab_alloc() for contexts where preemption is not yet - * disabled. Compensates for possible cpu changes by refetching the per cpu area - * pointer. - */ -static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, - unsigned long addr, struct kmem_cache_cpu *c, unsigned int orig_size) -{ - void *p; - -#ifdef CONFIG_PREEMPT_COUNT - /* - * We may have been preempted and rescheduled on a different - * cpu before disabling preemption. Need to reload cpu area - * pointer. - */ - c = slub_get_cpu_ptr(s->cpu_slab); -#endif - - p = ___slab_alloc(s, gfpflags, node, addr, c, orig_size); -#ifdef CONFIG_PREEMPT_COUNT - slub_put_cpu_ptr(s->cpu_slab); -#endif - return p; -} - -static __always_inline void *__slab_alloc_node(struct kmem_cache *s, - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) -{ - struct kmem_cache_cpu *c; - struct slab *slab; - unsigned long tid; - void *object; - -redo: - /* - * Must read kmem_cache cpu data via this cpu ptr. Preemption is - * enabled. We may switch back and forth between cpus while - * reading from one cpu area. That does not matter as long - * as we end up on the original cpu again when doing the cmpxchg. - * - * We must guarantee that tid and kmem_cache_cpu are retrieved on the - * same cpu. We read first the kmem_cache_cpu pointer and use it to read - * the tid. If we are preempted and switched to another cpu between the - * two reads, it's OK as the two are still associated with the same cpu - * and cmpxchg later will validate the cpu. - */ - c = raw_cpu_ptr(s->cpu_slab); - tid = READ_ONCE(c->tid); - - /* - * Irqless object alloc/free algorithm used here depends on sequence - * of fetching cpu_slab's data. tid should be fetched before anything - * on c to guarantee that object and slab associated with previous tid - * won't be used with current tid. If we fetch tid first, object and - * slab could be one associated with next tid and our alloc/free - * request will be failed. In this case, we will retry. So, no problem. - */ - barrier(); - - /* - * The transaction ids are globally unique per cpu and per operation on - * a per cpu queue. Thus they can be guarantee that the cmpxchg_double - * occurs on the right processor and that there was no operation on the - * linked list in between. - */ - - object = c->freelist; - slab = c->slab; - - if (!USE_LOCKLESS_FAST_PATH() || - unlikely(!object || !slab || !node_match(slab, node))) { - object = __slab_alloc(s, gfpflags, node, addr, c, orig_size); - } else { - void *next_object = get_freepointer_safe(s, object); - - /* - * The cmpxchg will only match if there was no additional - * operation and if we are on the right processor. - * - * The cmpxchg does the following atomically (without lock - * semantics!) - * 1. Relocate first pointer to the current per cpu area. - * 2. Verify that tid and freelist have not been changed - * 3. If they were not changed replace tid and freelist - * - * Since this is without lock semantics the protection is only - * against code executing on this cpu *not* from access by - * other cpus. - */ - if (unlikely(!this_cpu_cmpxchg_double( - s->cpu_slab->freelist, s->cpu_slab->tid, - object, tid, - next_object, next_tid(tid)))) { - - note_cmpxchg_failure("slab_alloc", s, tid); - goto redo; - } - prefetch_freepointer(s, next_object); - stat(s, ALLOC_FASTPATH); - } - - return object; -} -#else /* CONFIG_SLUB_TINY */ -static void *__slab_alloc_node(struct kmem_cache *s, - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) -{ - struct partial_context pc; - struct slab *slab; - void *object; - - pc.flags = gfpflags; - pc.slab = &slab; - pc.orig_size = orig_size; - object = get_partial(s, node, &pc); - - if (object) - return object; - - slab = new_slab(s, gfpflags, node); - if (unlikely(!slab)) { - slab_out_of_memory(s, gfpflags, node); - return NULL; - } - - object = alloc_single_from_new_slab(s, slab, orig_size); - - return object; -} -#endif /* CONFIG_SLUB_TINY */ - -/* - * If the object has been wiped upon free, make sure it's fully initialized by - * zeroing out freelist pointer. - */ -static __always_inline void maybe_wipe_obj_freeptr(struct kmem_cache *s, - void *obj) -{ - if (unlikely(slab_want_init_on_free(s)) && obj) - memset((void *)((char *)kasan_reset_tag(obj) + s->offset), - 0, sizeof(void *)); -} - -/* - * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc) - * have the fastpath folded into their functions. So no function call - * overhead for requests that can be satisfied on the fastpath. - * - * The fastpath works by first checking if the lockless freelist can be used. - * If not then __slab_alloc is called for slow processing. - * - * Otherwise we can simply pick the next object from the lockless free list. - */ -static __fastpath_inline void *slab_alloc_node(struct kmem_cache *s, struct list_lru *lru, - gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) -{ - void *object; - struct obj_cgroup *objcg = NULL; - bool init = false; - - s = slab_pre_alloc_hook(s, lru, &objcg, 1, gfpflags); - if (!s) - return NULL; - - object = kfence_alloc(s, orig_size, gfpflags); - if (unlikely(object)) - goto out; - - object = __slab_alloc_node(s, gfpflags, node, addr, orig_size); - - maybe_wipe_obj_freeptr(s, object); - init = slab_want_init_on_alloc(gfpflags, s); - -out: - /* - * When init equals 'true', like for kzalloc() family, only - * @orig_size bytes might be zeroed instead of s->object_size - */ - slab_post_alloc_hook(s, objcg, gfpflags, 1, &object, init, orig_size); - - return object; -} - -static __fastpath_inline void *slab_alloc(struct kmem_cache *s, struct list_lru *lru, - gfp_t gfpflags, unsigned long addr, size_t orig_size) -{ - return slab_alloc_node(s, lru, gfpflags, NUMA_NO_NODE, addr, orig_size); -} - -static __fastpath_inline -void *__kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, - gfp_t gfpflags) -{ - void *ret = slab_alloc(s, lru, gfpflags, _RET_IP_, s->object_size); - - trace_kmem_cache_alloc(_RET_IP_, ret, s, gfpflags, NUMA_NO_NODE); - - return ret; -} - -void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) -{ - return __kmem_cache_alloc_lru(s, NULL, gfpflags); -} -EXPORT_SYMBOL(kmem_cache_alloc); - -void *kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, - gfp_t gfpflags) -{ - return __kmem_cache_alloc_lru(s, lru, gfpflags); -} -EXPORT_SYMBOL(kmem_cache_alloc_lru); - -void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, - int node, size_t orig_size, - unsigned long caller) -{ - return slab_alloc_node(s, NULL, gfpflags, node, - caller, orig_size); -} - -void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node) -{ - void *ret = slab_alloc_node(s, NULL, gfpflags, node, _RET_IP_, s->object_size); - - trace_kmem_cache_alloc(_RET_IP_, ret, s, gfpflags, node); - - return ret; -} -EXPORT_SYMBOL(kmem_cache_alloc_node); - -static noinline void free_to_partial_list( - struct kmem_cache *s, struct slab *slab, - void *head, void *tail, int bulk_cnt, - unsigned long addr) -{ - struct kmem_cache_node *n = get_node(s, slab_nid(slab)); - struct slab *slab_free = NULL; - int cnt = bulk_cnt; - unsigned long flags; - depot_stack_handle_t handle = 0; - - if (s->flags & SLAB_STORE_USER) - handle = set_track_prepare(); - - spin_lock_irqsave(&n->list_lock, flags); - - if (free_debug_processing(s, slab, head, tail, &cnt, addr, handle)) { - void *prior = slab->freelist; - - /* Perform the actual freeing while we still hold the locks */ - slab->inuse -= cnt; - set_freepointer(s, tail, prior); - slab->freelist = head; - - /* - * If the slab is empty, and node's partial list is full, - * it should be discarded anyway no matter it's on full or - * partial list. - */ - if (slab->inuse == 0 && n->nr_partial >= s->min_partial) - slab_free = slab; - - if (!prior) { - /* was on full list */ - remove_full(s, n, slab); - if (!slab_free) { - add_partial(n, slab, DEACTIVATE_TO_TAIL); - stat(s, FREE_ADD_PARTIAL); - } - } else if (slab_free) { - remove_partial(n, slab); - stat(s, FREE_REMOVE_PARTIAL); - } - } - - if (slab_free) { - /* - * Update the counters while still holding n->list_lock to - * prevent spurious validation warnings - */ - dec_slabs_node(s, slab_nid(slab_free), slab_free->objects); - } - - spin_unlock_irqrestore(&n->list_lock, flags); - - if (slab_free) { - stat(s, FREE_SLAB); - free_slab(s, slab_free); - } -} - -/* - * Slow path handling. This may still be called frequently since objects - * have a longer lifetime than the cpu slabs in most processing loads. - * - * So we still attempt to reduce cache line usage. Just take the slab - * lock and free the item. If there is no additional partial slab - * handling required then we can return immediately. - */ -static void __slab_free(struct kmem_cache *s, struct slab *slab, - void *head, void *tail, int cnt, - unsigned long addr) - -{ - void *prior; - int was_frozen; - struct slab new; - unsigned long counters; - struct kmem_cache_node *n = NULL; - unsigned long flags; - - stat(s, FREE_SLOWPATH); - - if (kfence_free(head)) - return; - - if (IS_ENABLED(CONFIG_SLUB_TINY) || kmem_cache_debug(s)) { - free_to_partial_list(s, slab, head, tail, cnt, addr); - return; - } - - do { - if (unlikely(n)) { - spin_unlock_irqrestore(&n->list_lock, flags); - n = NULL; - } - prior = slab->freelist; - counters = slab->counters; - set_freepointer(s, tail, prior); - new.counters = counters; - was_frozen = new.frozen; - new.inuse -= cnt; - if ((!new.inuse || !prior) && !was_frozen) { - - if (kmem_cache_has_cpu_partial(s) && !prior) { - - /* - * Slab was on no list before and will be - * partially empty - * We can defer the list move and instead - * freeze it. - */ - new.frozen = 1; - - } else { /* Needs to be taken off a list */ - - n = get_node(s, slab_nid(slab)); - /* - * Speculatively acquire the list_lock. - * If the cmpxchg does not succeed then we may - * drop the list_lock without any processing. - * - * Otherwise the list_lock will synchronize with - * other processors updating the list of slabs. - */ - spin_lock_irqsave(&n->list_lock, flags); - - } - } - - } while (!cmpxchg_double_slab(s, slab, - prior, counters, - head, new.counters, - "__slab_free")); - - if (likely(!n)) { - - if (likely(was_frozen)) { - /* - * The list lock was not taken therefore no list - * activity can be necessary. - */ - stat(s, FREE_FROZEN); - } else if (new.frozen) { - /* - * If we just froze the slab then put it onto the - * per cpu partial list. - */ - put_cpu_partial(s, slab, 1); - stat(s, CPU_PARTIAL_FREE); - } - - return; - } - - if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) - goto slab_empty; - - /* - * Objects left in the slab. If it was not on the partial list before - * then add it. - */ - if (!kmem_cache_has_cpu_partial(s) && unlikely(!prior)) { - remove_full(s, n, slab); - add_partial(n, slab, DEACTIVATE_TO_TAIL); - stat(s, FREE_ADD_PARTIAL); - } - spin_unlock_irqrestore(&n->list_lock, flags); - return; - -slab_empty: - if (prior) { - /* - * Slab on the partial list. - */ - remove_partial(n, slab); - stat(s, FREE_REMOVE_PARTIAL); - } else { - /* Slab must be on the full list */ - remove_full(s, n, slab); - } - - spin_unlock_irqrestore(&n->list_lock, flags); - stat(s, FREE_SLAB); - discard_slab(s, slab); -} - -#ifndef CONFIG_SLUB_TINY -/* - * Fastpath with forced inlining to produce a kfree and kmem_cache_free that - * can perform fastpath freeing without additional function calls. - * - * The fastpath is only possible if we are freeing to the current cpu slab - * of this processor. This typically the case if we have just allocated - * the item before. - * - * If fastpath is not possible then fall back to __slab_free where we deal - * with all sorts of special processing. - * - * Bulk free of a freelist with several objects (all pointing to the - * same slab) possible by specifying head and tail ptr, plus objects - * count (cnt). Bulk free indicated by tail pointer being set. - */ -static __always_inline void do_slab_free(struct kmem_cache *s, - struct slab *slab, void *head, void *tail, - int cnt, unsigned long addr) -{ - void *tail_obj = tail ? : head; - struct kmem_cache_cpu *c; - unsigned long tid; - void **freelist; - -redo: - /* - * Determine the currently cpus per cpu slab. - * The cpu may change afterward. However that does not matter since - * data is retrieved via this pointer. If we are on the same cpu - * during the cmpxchg then the free will succeed. - */ - c = raw_cpu_ptr(s->cpu_slab); - tid = READ_ONCE(c->tid); - - /* Same with comment on barrier() in slab_alloc_node() */ - barrier(); - - if (unlikely(slab != c->slab)) { - __slab_free(s, slab, head, tail_obj, cnt, addr); - return; - } - - if (USE_LOCKLESS_FAST_PATH()) { - freelist = READ_ONCE(c->freelist); - - set_freepointer(s, tail_obj, freelist); - - if (unlikely(!this_cpu_cmpxchg_double( - s->cpu_slab->freelist, s->cpu_slab->tid, - freelist, tid, - head, next_tid(tid)))) { - - note_cmpxchg_failure("slab_free", s, tid); - goto redo; - } - } else { - /* Update the free list under the local lock */ - local_lock(&s->cpu_slab->lock); - c = this_cpu_ptr(s->cpu_slab); - if (unlikely(slab != c->slab)) { - local_unlock(&s->cpu_slab->lock); - goto redo; - } - tid = c->tid; - freelist = c->freelist; - - set_freepointer(s, tail_obj, freelist); - c->freelist = head; - c->tid = next_tid(tid); - - local_unlock(&s->cpu_slab->lock); - } - stat(s, FREE_FASTPATH); -} -#else /* CONFIG_SLUB_TINY */ -static void do_slab_free(struct kmem_cache *s, - struct slab *slab, void *head, void *tail, - int cnt, unsigned long addr) -{ - void *tail_obj = tail ? : head; - - __slab_free(s, slab, head, tail_obj, cnt, addr); -} -#endif /* CONFIG_SLUB_TINY */ - -static __fastpath_inline void slab_free(struct kmem_cache *s, struct slab *slab, - void *head, void *tail, void **p, int cnt, - unsigned long addr) -{ - memcg_slab_free_hook(s, slab, p, cnt); - /* - * With KASAN enabled slab_free_freelist_hook modifies the freelist - * to remove objects, whose reuse must be delayed. - */ - if (slab_free_freelist_hook(s, &head, &tail, &cnt)) - do_slab_free(s, slab, head, tail, cnt, addr); -} - -#ifdef CONFIG_KASAN_GENERIC -void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr) -{ - do_slab_free(cache, virt_to_slab(x), x, NULL, 1, addr); -} -#endif - -void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller) -{ - slab_free(s, virt_to_slab(x), x, NULL, &x, 1, caller); -} - -void kmem_cache_free(struct kmem_cache *s, void *x) -{ - s = cache_from_obj(s, x); - if (!s) - return; - trace_kmem_cache_free(_RET_IP_, x, s); - slab_free(s, virt_to_slab(x), x, NULL, &x, 1, _RET_IP_); -} -EXPORT_SYMBOL(kmem_cache_free); - -struct detached_freelist { - struct slab *slab; - void *tail; - void *freelist; - int cnt; - struct kmem_cache *s; -}; - -/* - * This function progressively scans the array with free objects (with - * a limited look ahead) and extract objects belonging to the same - * slab. It builds a detached freelist directly within the given - * slab/objects. This can happen without any need for - * synchronization, because the objects are owned by running process. - * The freelist is build up as a single linked list in the objects. - * The idea is, that this detached freelist can then be bulk - * transferred to the real freelist(s), but only requiring a single - * synchronization primitive. Look ahead in the array is limited due - * to performance reasons. - */ -static inline -int build_detached_freelist(struct kmem_cache *s, size_t size, - void **p, struct detached_freelist *df) -{ - int lookahead = 3; - void *object; - struct folio *folio; - size_t same; - - object = p[--size]; - folio = virt_to_folio(object); - if (!s) { - /* Handle kalloc'ed objects */ - if (unlikely(!folio_test_slab(folio))) { - free_large_kmalloc(folio, object); - df->slab = NULL; - return size; - } - /* Derive kmem_cache from object */ - df->slab = folio_slab(folio); - df->s = df->slab->slab_cache; - } else { - df->slab = folio_slab(folio); - df->s = cache_from_obj(s, object); /* Support for memcg */ - } - - /* Start new detached freelist */ - df->tail = object; - df->freelist = object; - df->cnt = 1; - - if (is_kfence_address(object)) - return size; - - set_freepointer(df->s, object, NULL); - - same = size; - while (size) { - object = p[--size]; - /* df->slab is always set at this point */ - if (df->slab == virt_to_slab(object)) { - /* Opportunity build freelist */ - set_freepointer(df->s, object, df->freelist); - df->freelist = object; - df->cnt++; - same--; - if (size != same) - swap(p[size], p[same]); - continue; - } - - /* Limit look ahead search */ - if (!--lookahead) - break; - } - - return same; -} - -/* Note that interrupts must be enabled when calling this function. */ -void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p) -{ - if (!size) - return; - - do { - struct detached_freelist df; - - size = build_detached_freelist(s, size, p, &df); - if (!df.slab) - continue; - - slab_free(df.s, df.slab, df.freelist, df.tail, &p[size], df.cnt, - _RET_IP_); - } while (likely(size)); -} -EXPORT_SYMBOL(kmem_cache_free_bulk); - -#ifndef CONFIG_SLUB_TINY -static inline int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, - size_t size, void **p, struct obj_cgroup *objcg) -{ - struct kmem_cache_cpu *c; - unsigned long irqflags; - int i; - - /* - * Drain objects in the per cpu slab, while disabling local - * IRQs, which protects against PREEMPT and interrupts - * handlers invoking normal fastpath. - */ - c = slub_get_cpu_ptr(s->cpu_slab); - local_lock_irqsave(&s->cpu_slab->lock, irqflags); - - for (i = 0; i < size; i++) { - void *object = kfence_alloc(s, s->object_size, flags); - - if (unlikely(object)) { - p[i] = object; - continue; - } - - object = c->freelist; - if (unlikely(!object)) { - /* - * We may have removed an object from c->freelist using - * the fastpath in the previous iteration; in that case, - * c->tid has not been bumped yet. - * Since ___slab_alloc() may reenable interrupts while - * allocating memory, we should bump c->tid now. - */ - c->tid = next_tid(c->tid); - - local_unlock_irqrestore(&s->cpu_slab->lock, irqflags); - - /* - * Invoking slow path likely have side-effect - * of re-populating per CPU c->freelist - */ - p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE, - _RET_IP_, c, s->object_size); - if (unlikely(!p[i])) - goto error; - - c = this_cpu_ptr(s->cpu_slab); - maybe_wipe_obj_freeptr(s, p[i]); - - local_lock_irqsave(&s->cpu_slab->lock, irqflags); - - continue; /* goto for-loop */ - } - c->freelist = get_freepointer(s, object); - p[i] = object; - maybe_wipe_obj_freeptr(s, p[i]); - } - c->tid = next_tid(c->tid); - local_unlock_irqrestore(&s->cpu_slab->lock, irqflags); - slub_put_cpu_ptr(s->cpu_slab); - - return i; - -error: - slub_put_cpu_ptr(s->cpu_slab); - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); - kmem_cache_free_bulk(s, i, p); - return 0; - -} -#else /* CONFIG_SLUB_TINY */ -static int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, - size_t size, void **p, struct obj_cgroup *objcg) -{ - int i; - - for (i = 0; i < size; i++) { - void *object = kfence_alloc(s, s->object_size, flags); - - if (unlikely(object)) { - p[i] = object; - continue; - } - - p[i] = __slab_alloc_node(s, flags, NUMA_NO_NODE, - _RET_IP_, s->object_size); - if (unlikely(!p[i])) - goto error; - - maybe_wipe_obj_freeptr(s, p[i]); - } - - return i; - -error: - slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size); - kmem_cache_free_bulk(s, i, p); - return 0; -} -#endif /* CONFIG_SLUB_TINY */ - -/* Note that interrupts must be enabled when calling this function. */ -int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, - void **p) -{ - int i; - struct obj_cgroup *objcg = NULL; - - if (!size) - return 0; - - /* memcg and kmem_cache debug support */ - s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); - if (unlikely(!s)) - return 0; - - i = __kmem_cache_alloc_bulk(s, flags, size, p, objcg); - - /* - * memcg and kmem_cache debug support and memory initialization. - * Done outside of the IRQ disabled fastpath loop. - */ - if (i != 0) - slab_post_alloc_hook(s, objcg, flags, size, p, - slab_want_init_on_alloc(flags, s), s->object_size); - return i; -} -EXPORT_SYMBOL(kmem_cache_alloc_bulk); - - -/* - * Object placement in a slab is made very easy because we always start at - * offset 0. If we tune the size of the object to the alignment then we can - * get the required alignment by putting one properly sized object after - * another. - * - * Notice that the allocation order determines the sizes of the per cpu - * caches. Each processor has always one slab available for allocations. - * Increasing the allocation order reduces the number of times that slabs - * must be moved on and off the partial lists and is therefore a factor in - * locking overhead. - */ - -/* - * Minimum / Maximum order of slab pages. This influences locking overhead - * and slab fragmentation. A higher order reduces the number of partial slabs - * and increases the number of allocations possible without having to - * take the list_lock. - */ -static unsigned int slub_min_order; -static unsigned int slub_max_order = - IS_ENABLED(CONFIG_SLUB_TINY) ? 1 : PAGE_ALLOC_COSTLY_ORDER; -static unsigned int slub_min_objects; - -/* - * Calculate the order of allocation given an slab object size. - * - * The order of allocation has significant impact on performance and other - * system components. Generally order 0 allocations should be preferred since - * order 0 does not cause fragmentation in the page allocator. Larger objects - * be problematic to put into order 0 slabs because there may be too much - * unused space left. We go to a higher order if more than 1/16th of the slab - * would be wasted. - * - * In order to reach satisfactory performance we must ensure that a minimum - * number of objects is in one slab. Otherwise we may generate too much - * activity on the partial lists which requires taking the list_lock. This is - * less a concern for large slabs though which are rarely used. - * - * slub_max_order specifies the order where we begin to stop considering the - * number of objects in a slab as critical. If we reach slub_max_order then - * we try to keep the page order as low as possible. So we accept more waste - * of space in favor of a small page order. - * - * Higher order allocations also allow the placement of more objects in a - * slab and thereby reduce object handling overhead. If the user has - * requested a higher minimum order then we start with that one instead of - * the smallest order which will fit the object. - */ -static inline unsigned int calc_slab_order(unsigned int size, - unsigned int min_objects, unsigned int max_order, - unsigned int fract_leftover) -{ - unsigned int min_order = slub_min_order; - unsigned int order; - - if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE) - return get_order(size * MAX_OBJS_PER_PAGE) - 1; - - for (order = max(min_order, (unsigned int)get_order(min_objects * size)); - order <= max_order; order++) { - - unsigned int slab_size = (unsigned int)PAGE_SIZE << order; - unsigned int rem; - - rem = slab_size % size; - - if (rem <= slab_size / fract_leftover) - break; - } - - return order; -} - -static inline int calculate_order(unsigned int size) -{ - unsigned int order; - unsigned int min_objects; - unsigned int max_objects; - unsigned int nr_cpus; - - /* - * Attempt to find best configuration for a slab. This - * works by first attempting to generate a layout with - * the best configuration and backing off gradually. - * - * First we increase the acceptable waste in a slab. Then - * we reduce the minimum objects required in a slab. - */ - min_objects = slub_min_objects; - if (!min_objects) { - /* - * Some architectures will only update present cpus when - * onlining them, so don't trust the number if it's just 1. But - * we also don't want to use nr_cpu_ids always, as on some other - * architectures, there can be many possible cpus, but never - * onlined. Here we compromise between trying to avoid too high - * order on systems that appear larger than they are, and too - * low order on systems that appear smaller than they are. - */ - nr_cpus = num_present_cpus(); - if (nr_cpus <= 1) - nr_cpus = nr_cpu_ids; - min_objects = 4 * (fls(nr_cpus) + 1); - } - max_objects = order_objects(slub_max_order, size); - min_objects = min(min_objects, max_objects); - - while (min_objects > 1) { - unsigned int fraction; - - fraction = 16; - while (fraction >= 4) { - order = calc_slab_order(size, min_objects, - slub_max_order, fraction); - if (order <= slub_max_order) - return order; - fraction /= 2; - } - min_objects--; - } - - /* - * We were unable to place multiple objects in a slab. Now - * lets see if we can place a single object there. - */ - order = calc_slab_order(size, 1, slub_max_order, 1); - if (order <= slub_max_order) - return order; - - /* - * Doh this slab cannot be placed using slub_max_order. - */ - order = calc_slab_order(size, 1, MAX_ORDER, 1); - if (order < MAX_ORDER) - return order; - return -ENOSYS; -} - -static void -init_kmem_cache_node(struct kmem_cache_node *n) -{ - n->nr_partial = 0; - spin_lock_init(&n->list_lock); - INIT_LIST_HEAD(&n->partial); -#ifdef CONFIG_SLUB_DEBUG - atomic_long_set(&n->nr_slabs, 0); - atomic_long_set(&n->total_objects, 0); - INIT_LIST_HEAD(&n->full); -#endif -} - -#ifndef CONFIG_SLUB_TINY -static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) -{ - BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE < - NR_KMALLOC_TYPES * KMALLOC_SHIFT_HIGH * - sizeof(struct kmem_cache_cpu)); - - /* - * Must align to double word boundary for the double cmpxchg - * instructions to work; see __pcpu_double_call_return_bool(). - */ - s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu), - 2 * sizeof(void *)); - - if (!s->cpu_slab) - return 0; - - init_kmem_cache_cpus(s); - - return 1; -} -#else -static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) -{ - return 1; -} -#endif /* CONFIG_SLUB_TINY */ - -static struct kmem_cache *kmem_cache_node; - -/* - * No kmalloc_node yet so do it by hand. We know that this is the first - * slab on the node for this slabcache. There are no concurrent accesses - * possible. - * - * Note that this function only works on the kmem_cache_node - * when allocating for the kmem_cache_node. This is used for bootstrapping - * memory on a fresh node that has no slab structures yet. - */ -static void early_kmem_cache_node_alloc(int node) -{ - struct slab *slab; - struct kmem_cache_node *n; - - BUG_ON(kmem_cache_node->size < sizeof(struct kmem_cache_node)); - - slab = new_slab(kmem_cache_node, GFP_NOWAIT, node); - - BUG_ON(!slab); - inc_slabs_node(kmem_cache_node, slab_nid(slab), slab->objects); - if (slab_nid(slab) != node) { - pr_err("SLUB: Unable to allocate memory from node %d\n", node); - pr_err("SLUB: Allocating a useless per node structure in order to be able to continue\n"); - } - - n = slab->freelist; - BUG_ON(!n); -#ifdef CONFIG_SLUB_DEBUG - init_object(kmem_cache_node, n, SLUB_RED_ACTIVE); - init_tracking(kmem_cache_node, n); -#endif - n = kasan_slab_alloc(kmem_cache_node, n, GFP_KERNEL, false); - slab->freelist = get_freepointer(kmem_cache_node, n); - slab->inuse = 1; - kmem_cache_node->node[node] = n; - init_kmem_cache_node(n); - inc_slabs_node(kmem_cache_node, node, slab->objects); - - /* - * No locks need to be taken here as it has just been - * initialized and there is no concurrent access. - */ - __add_partial(n, slab, DEACTIVATE_TO_HEAD); -} - -static void free_kmem_cache_nodes(struct kmem_cache *s) -{ - int node; - struct kmem_cache_node *n; - - for_each_kmem_cache_node(s, node, n) { - s->node[node] = NULL; - kmem_cache_free(kmem_cache_node, n); - } -} - -void __kmem_cache_release(struct kmem_cache *s) -{ - cache_random_seq_destroy(s); -#ifndef CONFIG_SLUB_TINY - free_percpu(s->cpu_slab); -#endif - free_kmem_cache_nodes(s); -} - -static int init_kmem_cache_nodes(struct kmem_cache *s) -{ - int node; - - for_each_node_mask(node, slab_nodes) { - struct kmem_cache_node *n; - - if (slab_state == DOWN) { - early_kmem_cache_node_alloc(node); - continue; - } - n = kmem_cache_alloc_node(kmem_cache_node, - GFP_KERNEL, node); - - if (!n) { - free_kmem_cache_nodes(s); - return 0; - } - - init_kmem_cache_node(n); - s->node[node] = n; - } - return 1; -} - -static void set_cpu_partial(struct kmem_cache *s) -{ -#ifdef CONFIG_SLUB_CPU_PARTIAL - unsigned int nr_objects; - - /* - * cpu_partial determined the maximum number of objects kept in the - * per cpu partial lists of a processor. - * - * Per cpu partial lists mainly contain slabs that just have one - * object freed. If they are used for allocation then they can be - * filled up again with minimal effort. The slab will never hit the - * per node partial lists and therefore no locking will be required. - * - * For backwards compatibility reasons, this is determined as number - * of objects, even though we now limit maximum number of pages, see - * slub_set_cpu_partial() - */ - if (!kmem_cache_has_cpu_partial(s)) - nr_objects = 0; - else if (s->size >= PAGE_SIZE) - nr_objects = 6; - else if (s->size >= 1024) - nr_objects = 24; - else if (s->size >= 256) - nr_objects = 52; - else - nr_objects = 120; - - slub_set_cpu_partial(s, nr_objects); -#endif -} - -/* - * calculate_sizes() determines the order and the distribution of data within - * a slab object. - */ -static int calculate_sizes(struct kmem_cache *s) -{ - slab_flags_t flags = s->flags; - unsigned int size = s->object_size; - unsigned int order; - - /* - * Round up object size to the next word boundary. We can only - * place the free pointer at word boundaries and this determines - * the possible location of the free pointer. - */ - size = ALIGN(size, sizeof(void *)); - -#ifdef CONFIG_SLUB_DEBUG - /* - * Determine if we can poison the object itself. If the user of - * the slab may touch the object after free or before allocation - * then we should never poison the object itself. - */ - if ((flags & SLAB_POISON) && !(flags & SLAB_TYPESAFE_BY_RCU) && - !s->ctor) - s->flags |= __OBJECT_POISON; - else - s->flags &= ~__OBJECT_POISON; - - - /* - * If we are Redzoning then check if there is some space between the - * end of the object and the free pointer. If not then add an - * additional word to have some bytes to store Redzone information. - */ - if ((flags & SLAB_RED_ZONE) && size == s->object_size) - size += sizeof(void *); -#endif - - /* - * With that we have determined the number of bytes in actual use - * by the object and redzoning. - */ - s->inuse = size; - - if (slub_debug_orig_size(s) || - (flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) || - ((flags & SLAB_RED_ZONE) && s->object_size < sizeof(void *)) || - s->ctor) { - /* - * Relocate free pointer after the object if it is not - * permitted to overwrite the first word of the object on - * kmem_cache_free. - * - * This is the case if we do RCU, have a constructor or - * destructor, are poisoning the objects, or are - * redzoning an object smaller than sizeof(void *). - * - * The assumption that s->offset >= s->inuse means free - * pointer is outside of the object is used in the - * freeptr_outside_object() function. If that is no - * longer true, the function needs to be modified. - */ - s->offset = size; - size += sizeof(void *); - } else { - /* - * Store freelist pointer near middle of object to keep - * it away from the edges of the object to avoid small - * sized over/underflows from neighboring allocations. - */ - s->offset = ALIGN_DOWN(s->object_size / 2, sizeof(void *)); - } - -#ifdef CONFIG_SLUB_DEBUG - if (flags & SLAB_STORE_USER) { - /* - * Need to store information about allocs and frees after - * the object. - */ - size += 2 * sizeof(struct track); - - /* Save the original kmalloc request size */ - if (flags & SLAB_KMALLOC) - size += sizeof(unsigned int); - } -#endif - - kasan_cache_create(s, &size, &s->flags); -#ifdef CONFIG_SLUB_DEBUG - if (flags & SLAB_RED_ZONE) { - /* - * Add some empty padding so that we can catch - * overwrites from earlier objects rather than let - * tracking information or the free pointer be - * corrupted if a user writes before the start - * of the object. - */ - size += sizeof(void *); - - s->red_left_pad = sizeof(void *); - s->red_left_pad = ALIGN(s->red_left_pad, s->align); - size += s->red_left_pad; - } -#endif - - /* - * SLUB stores one object immediately after another beginning from - * offset 0. In order to align the objects we have to simply size - * each object to conform to the alignment. - */ - size = ALIGN(size, s->align); - s->size = size; - s->reciprocal_size = reciprocal_value(size); - order = calculate_order(size); - - if ((int)order < 0) - return 0; - - s->allocflags = 0; - if (order) - s->allocflags |= __GFP_COMP; - - if (s->flags & SLAB_CACHE_DMA) - s->allocflags |= GFP_DMA; - - if (s->flags & SLAB_CACHE_DMA32) - s->allocflags |= GFP_DMA32; - - if (s->flags & SLAB_RECLAIM_ACCOUNT) - s->allocflags |= __GFP_RECLAIMABLE; - - /* - * Determine the number of objects per slab - */ - s->oo = oo_make(order, size); - s->min = oo_make(get_order(size), size); - - return !!oo_objects(s->oo); -} - -static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags) -{ - s->flags = kmem_cache_flags(s->size, flags, s->name); -#ifdef CONFIG_SLAB_FREELIST_HARDENED - s->random = get_random_long(); -#endif - - if (!calculate_sizes(s)) - goto error; - if (disable_higher_order_debug) { - /* - * Disable debugging flags that store metadata if the min slab - * order increased. - */ - if (get_order(s->size) > get_order(s->object_size)) { - s->flags &= ~DEBUG_METADATA_FLAGS; - s->offset = 0; - if (!calculate_sizes(s)) - goto error; - } - } - -#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ - defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) - if (system_has_cmpxchg_double() && (s->flags & SLAB_NO_CMPXCHG) == 0) - /* Enable fast mode */ - s->flags |= __CMPXCHG_DOUBLE; -#endif - - /* - * The larger the object size is, the more slabs we want on the partial - * list to avoid pounding the page allocator excessively. - */ - s->min_partial = min_t(unsigned long, MAX_PARTIAL, ilog2(s->size) / 2); - s->min_partial = max_t(unsigned long, MIN_PARTIAL, s->min_partial); - - set_cpu_partial(s); - -#ifdef CONFIG_NUMA - s->remote_node_defrag_ratio = 1000; -#endif - - /* Initialize the pre-computed randomized freelist if slab is up */ - if (slab_state >= UP) { - if (init_cache_random_seq(s)) - goto error; - } - - if (!init_kmem_cache_nodes(s)) - goto error; - - if (alloc_kmem_cache_cpus(s)) - return 0; - -error: - __kmem_cache_release(s); - return -EINVAL; -} - -static void list_slab_objects(struct kmem_cache *s, struct slab *slab, - const char *text) -{ -#ifdef CONFIG_SLUB_DEBUG - void *addr = slab_address(slab); - void *p; - - slab_err(s, slab, text, s->name); - - spin_lock(&object_map_lock); - __fill_map(object_map, s, slab); - - for_each_object(p, s, addr, slab->objects) { - - if (!test_bit(__obj_to_index(s, addr, p), object_map)) { - pr_err("Object 0x%p @offset=%tu\n", p, p - addr); - print_tracking(s, p); - } - } - spin_unlock(&object_map_lock); -#endif -} - -/* - * Attempt to free all partial slabs on a node. - * This is called from __kmem_cache_shutdown(). We must take list_lock - * because sysfs file might still access partial list after the shutdowning. - */ -static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n) -{ - LIST_HEAD(discard); - struct slab *slab, *h; - - BUG_ON(irqs_disabled()); - spin_lock_irq(&n->list_lock); - list_for_each_entry_safe(slab, h, &n->partial, slab_list) { - if (!slab->inuse) { - remove_partial(n, slab); - list_add(&slab->slab_list, &discard); - } else { - list_slab_objects(s, slab, - "Objects remaining in %s on __kmem_cache_shutdown()"); - } - } - spin_unlock_irq(&n->list_lock); - - list_for_each_entry_safe(slab, h, &discard, slab_list) - discard_slab(s, slab); -} - -bool __kmem_cache_empty(struct kmem_cache *s) -{ - int node; - struct kmem_cache_node *n; - - for_each_kmem_cache_node(s, node, n) - if (n->nr_partial || slabs_node(s, node)) - return false; - return true; -} - -/* - * Release all resources used by a slab cache. - */ -int __kmem_cache_shutdown(struct kmem_cache *s) -{ - int node; - struct kmem_cache_node *n; - - flush_all_cpus_locked(s); - /* Attempt to free all objects */ - for_each_kmem_cache_node(s, node, n) { - free_partial(s, n); - if (n->nr_partial || slabs_node(s, node)) - return 1; - } - return 0; -} - -#ifdef CONFIG_PRINTK -void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) -{ - void *base; - int __maybe_unused i; - unsigned int objnr; - void *objp; - void *objp0; - struct kmem_cache *s = slab->slab_cache; - struct track __maybe_unused *trackp; - - kpp->kp_ptr = object; - kpp->kp_slab = slab; - kpp->kp_slab_cache = s; - base = slab_address(slab); - objp0 = kasan_reset_tag(object); -#ifdef CONFIG_SLUB_DEBUG - objp = restore_red_left(s, objp0); -#else - objp = objp0; -#endif - objnr = obj_to_index(s, slab, objp); - kpp->kp_data_offset = (unsigned long)((char *)objp0 - (char *)objp); - objp = base + s->size * objnr; - kpp->kp_objp = objp; - if (WARN_ON_ONCE(objp < base || objp >= base + slab->objects * s->size - || (objp - base) % s->size) || - !(s->flags & SLAB_STORE_USER)) - return; -#ifdef CONFIG_SLUB_DEBUG - objp = fixup_red_left(s, objp); - trackp = get_track(s, objp, TRACK_ALLOC); - kpp->kp_ret = (void *)trackp->addr; -#ifdef CONFIG_STACKDEPOT - { - depot_stack_handle_t handle; - unsigned long *entries; - unsigned int nr_entries; - - handle = READ_ONCE(trackp->handle); - if (handle) { - nr_entries = stack_depot_fetch(handle, &entries); - for (i = 0; i < KS_ADDRS_COUNT && i < nr_entries; i++) - kpp->kp_stack[i] = (void *)entries[i]; - } - - trackp = get_track(s, objp, TRACK_FREE); - handle = READ_ONCE(trackp->handle); - if (handle) { - nr_entries = stack_depot_fetch(handle, &entries); - for (i = 0; i < KS_ADDRS_COUNT && i < nr_entries; i++) - kpp->kp_free_stack[i] = (void *)entries[i]; - } - } -#endif -#endif -} -#endif - -/******************************************************************** - * Kmalloc subsystem - *******************************************************************/ - -static int __init setup_slub_min_order(char *str) -{ - get_option(&str, (int *)&slub_min_order); - - return 1; -} - -__setup("slub_min_order=", setup_slub_min_order); - -static int __init setup_slub_max_order(char *str) -{ - get_option(&str, (int *)&slub_max_order); - slub_max_order = min(slub_max_order, (unsigned int)MAX_ORDER - 1); - - return 1; -} - -__setup("slub_max_order=", setup_slub_max_order); - -static int __init setup_slub_min_objects(char *str) -{ - get_option(&str, (int *)&slub_min_objects); - - return 1; -} - -__setup("slub_min_objects=", setup_slub_min_objects); - -#ifdef CONFIG_HARDENED_USERCOPY -/* - * Rejects incorrectly sized objects and objects that are to be copied - * to/from userspace but do not fall entirely within the containing slab - * cache's usercopy region. - * - * Returns NULL if check passes, otherwise const char * to name of cache - * to indicate an error. - */ -void __check_heap_object(const void *ptr, unsigned long n, - const struct slab *slab, bool to_user) -{ - struct kmem_cache *s; - unsigned int offset; - bool is_kfence = is_kfence_address(ptr); - - ptr = kasan_reset_tag(ptr); - - /* Find object and usable object size. */ - s = slab->slab_cache; - - /* Reject impossible pointers. */ - if (ptr < slab_address(slab)) - usercopy_abort("SLUB object not in SLUB page?!", NULL, - to_user, 0, n); - - /* Find offset within object. */ - if (is_kfence) - offset = ptr - kfence_object_start(ptr); - else - offset = (ptr - slab_address(slab)) % s->size; - - /* Adjust for redzone and reject if within the redzone. */ - if (!is_kfence && kmem_cache_debug_flags(s, SLAB_RED_ZONE)) { - if (offset < s->red_left_pad) - usercopy_abort("SLUB object in left red zone", - s->name, to_user, offset, n); - offset -= s->red_left_pad; - } - - /* Allow address range falling entirely within usercopy region. */ - if (offset >= s->useroffset && - offset - s->useroffset <= s->usersize && - n <= s->useroffset - offset + s->usersize) - return; - - usercopy_abort("SLUB object", s->name, to_user, offset, n); -} -#endif /* CONFIG_HARDENED_USERCOPY */ - -#define SHRINK_PROMOTE_MAX 32 - -/* - * kmem_cache_shrink discards empty slabs and promotes the slabs filled - * up most to the head of the partial lists. New allocations will then - * fill those up and thus they can be removed from the partial lists. - * - * The slabs with the least items are placed last. This results in them - * being allocated from last increasing the chance that the last objects - * are freed in them. - */ -static int __kmem_cache_do_shrink(struct kmem_cache *s) -{ - int node; - int i; - struct kmem_cache_node *n; - struct slab *slab; - struct slab *t; - struct list_head discard; - struct list_head promote[SHRINK_PROMOTE_MAX]; - unsigned long flags; - int ret = 0; - - for_each_kmem_cache_node(s, node, n) { - INIT_LIST_HEAD(&discard); - for (i = 0; i < SHRINK_PROMOTE_MAX; i++) - INIT_LIST_HEAD(promote + i); - - spin_lock_irqsave(&n->list_lock, flags); - - /* - * Build lists of slabs to discard or promote. - * - * Note that concurrent frees may occur while we hold the - * list_lock. slab->inuse here is the upper limit. - */ - list_for_each_entry_safe(slab, t, &n->partial, slab_list) { - int free = slab->objects - slab->inuse; - - /* Do not reread slab->inuse */ - barrier(); - - /* We do not keep full slabs on the list */ - BUG_ON(free <= 0); - - if (free == slab->objects) { - list_move(&slab->slab_list, &discard); - n->nr_partial--; - dec_slabs_node(s, node, slab->objects); - } else if (free <= SHRINK_PROMOTE_MAX) - list_move(&slab->slab_list, promote + free - 1); - } - - /* - * Promote the slabs filled up most to the head of the - * partial list. - */ - for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--) - list_splice(promote + i, &n->partial); - - spin_unlock_irqrestore(&n->list_lock, flags); - - /* Release empty slabs */ - list_for_each_entry_safe(slab, t, &discard, slab_list) - free_slab(s, slab); - - if (slabs_node(s, node)) - ret = 1; - } - - return ret; -} - -int __kmem_cache_shrink(struct kmem_cache *s) -{ - flush_all(s); - return __kmem_cache_do_shrink(s); -} - -static int slab_mem_going_offline_callback(void *arg) -{ - struct kmem_cache *s; - - mutex_lock(&slab_mutex); - list_for_each_entry(s, &slab_caches, list) { - flush_all_cpus_locked(s); - __kmem_cache_do_shrink(s); - } - mutex_unlock(&slab_mutex); - - return 0; -} - -static void slab_mem_offline_callback(void *arg) -{ - struct memory_notify *marg = arg; - int offline_node; - - offline_node = marg->status_change_nid_normal; - - /* - * If the node still has available memory. we need kmem_cache_node - * for it yet. - */ - if (offline_node < 0) - return; - - mutex_lock(&slab_mutex); - node_clear(offline_node, slab_nodes); - /* - * We no longer free kmem_cache_node structures here, as it would be - * racy with all get_node() users, and infeasible to protect them with - * slab_mutex. - */ - mutex_unlock(&slab_mutex); -} - -static int slab_mem_going_online_callback(void *arg) -{ - struct kmem_cache_node *n; - struct kmem_cache *s; - struct memory_notify *marg = arg; - int nid = marg->status_change_nid_normal; - int ret = 0; - - /* - * If the node's memory is already available, then kmem_cache_node is - * already created. Nothing to do. - */ - if (nid < 0) - return 0; - - /* - * We are bringing a node online. No memory is available yet. We must - * allocate a kmem_cache_node structure in order to bring the node - * online. - */ - mutex_lock(&slab_mutex); - list_for_each_entry(s, &slab_caches, list) { - /* - * The structure may already exist if the node was previously - * onlined and offlined. - */ - if (get_node(s, nid)) - continue; - /* - * XXX: kmem_cache_alloc_node will fallback to other nodes - * since memory is not yet available from the node that - * is brought up. - */ - n = kmem_cache_alloc(kmem_cache_node, GFP_KERNEL); - if (!n) { - ret = -ENOMEM; - goto out; - } - init_kmem_cache_node(n); - s->node[nid] = n; - } - /* - * Any cache created after this point will also have kmem_cache_node - * initialized for the new node. - */ - node_set(nid, slab_nodes); -out: - mutex_unlock(&slab_mutex); - return ret; -} - -static int slab_memory_callback(struct notifier_block *self, - unsigned long action, void *arg) -{ - int ret = 0; - - switch (action) { - case MEM_GOING_ONLINE: - ret = slab_mem_going_online_callback(arg); - break; - case MEM_GOING_OFFLINE: - ret = slab_mem_going_offline_callback(arg); - break; - case MEM_OFFLINE: - case MEM_CANCEL_ONLINE: - slab_mem_offline_callback(arg); - break; - case MEM_ONLINE: - case MEM_CANCEL_OFFLINE: - break; - } - if (ret) - ret = notifier_from_errno(ret); - else - ret = NOTIFY_OK; - return ret; -} - -/******************************************************************** - * Basic setup of slabs - *******************************************************************/ - -/* - * Used for early kmem_cache structures that were allocated using - * the page allocator. Allocate them properly then fix up the pointers - * that may be pointing to the wrong kmem_cache structure. - */ - -static struct kmem_cache * __init bootstrap(struct kmem_cache *static_cache) -{ - int node; - struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); - struct kmem_cache_node *n; - - memcpy(s, static_cache, kmem_cache->object_size); - - /* - * This runs very early, and only the boot processor is supposed to be - * up. Even if it weren't true, IRQs are not up so we couldn't fire - * IPIs around. - */ - __flush_cpu_slab(s, smp_processor_id()); - for_each_kmem_cache_node(s, node, n) { - struct slab *p; - - list_for_each_entry(p, &n->partial, slab_list) - p->slab_cache = s; - -#ifdef CONFIG_SLUB_DEBUG - list_for_each_entry(p, &n->full, slab_list) - p->slab_cache = s; -#endif - } - list_add(&s->list, &slab_caches); - return s; -} - -void __init kmem_cache_init(void) -{ - static __initdata struct kmem_cache boot_kmem_cache, - boot_kmem_cache_node; - int node; - - if (debug_guardpage_minorder()) - slub_max_order = 0; - - /* Print slub debugging pointers without hashing */ - if (__slub_debug_enabled()) - no_hash_pointers_enable(NULL); - - kmem_cache_node = &boot_kmem_cache_node; - kmem_cache = &boot_kmem_cache; - - /* - * Initialize the nodemask for which we will allocate per node - * structures. Here we don't need taking slab_mutex yet. - */ - for_each_node_state(node, N_NORMAL_MEMORY) - node_set(node, slab_nodes); - - create_boot_cache(kmem_cache_node, "kmem_cache_node", - sizeof(struct kmem_cache_node), SLAB_HWCACHE_ALIGN, 0, 0); - - hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI); - - /* Able to allocate the per node structures */ - slab_state = PARTIAL; - - create_boot_cache(kmem_cache, "kmem_cache", - offsetof(struct kmem_cache, node) + - nr_node_ids * sizeof(struct kmem_cache_node *), - SLAB_HWCACHE_ALIGN, 0, 0); - - kmem_cache = bootstrap(&boot_kmem_cache); - kmem_cache_node = bootstrap(&boot_kmem_cache_node); - - /* Now we can use the kmem_cache to allocate kmalloc slabs */ - setup_kmalloc_cache_index_table(); - create_kmalloc_caches(0); - - /* Setup random freelists for each cache */ - init_freelist_randomization(); - - cpuhp_setup_state_nocalls(CPUHP_SLUB_DEAD, "slub:dead", NULL, - slub_cpu_dead); - - pr_info("SLUB: HWalign=%d, Order=%u-%u, MinObjects=%u, CPUs=%u, Nodes=%u\n", - cache_line_size(), - slub_min_order, slub_max_order, slub_min_objects, - nr_cpu_ids, nr_node_ids); -} - -void __init kmem_cache_init_late(void) -{ -#ifndef CONFIG_SLUB_TINY - flushwq = alloc_workqueue("slub_flushwq", WQ_MEM_RECLAIM, 0); - WARN_ON(!flushwq); -#endif -} - -struct kmem_cache * -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, - slab_flags_t flags, void (*ctor)(void *)) -{ - struct kmem_cache *s; - - s = find_mergeable(size, align, flags, name, ctor); - if (s) { - if (sysfs_slab_alias(s, name)) - return NULL; - - s->refcount++; - - /* - * Adjust the object sizes so that we clear - * the complete object on kzalloc. - */ - s->object_size = max(s->object_size, size); - s->inuse = max(s->inuse, ALIGN(size, sizeof(void *))); - } - - return s; -} - -int __kmem_cache_create(struct kmem_cache *s, slab_flags_t flags) -{ - int err; - - err = kmem_cache_open(s, flags); - if (err) - return err; - - /* Mutex is not taken during early boot */ - if (slab_state <= UP) - return 0; - - err = sysfs_slab_add(s); - if (err) { - __kmem_cache_release(s); - return err; - } - - if (s->flags & SLAB_STORE_USER) - debugfs_slab_add(s); - - return 0; -} - -#ifdef SLAB_SUPPORTS_SYSFS -static int count_inuse(struct slab *slab) -{ - return slab->inuse; -} - -static int count_total(struct slab *slab) -{ - return slab->objects; -} -#endif - -#ifdef CONFIG_SLUB_DEBUG -static void validate_slab(struct kmem_cache *s, struct slab *slab, - unsigned long *obj_map) -{ - void *p; - void *addr = slab_address(slab); - - if (!check_slab(s, slab) || !on_freelist(s, slab, NULL)) - return; - - /* Now we know that a valid freelist exists */ - __fill_map(obj_map, s, slab); - for_each_object(p, s, addr, slab->objects) { - u8 val = test_bit(__obj_to_index(s, addr, p), obj_map) ? - SLUB_RED_INACTIVE : SLUB_RED_ACTIVE; - - if (!check_object(s, slab, p, val)) - break; - } -} - -static int validate_slab_node(struct kmem_cache *s, - struct kmem_cache_node *n, unsigned long *obj_map) -{ - unsigned long count = 0; - struct slab *slab; - unsigned long flags; - - spin_lock_irqsave(&n->list_lock, flags); - - list_for_each_entry(slab, &n->partial, slab_list) { - validate_slab(s, slab, obj_map); - count++; - } - if (count != n->nr_partial) { - pr_err("SLUB %s: %ld partial slabs counted but counter=%ld\n", - s->name, count, n->nr_partial); - slab_add_kunit_errors(); - } - - if (!(s->flags & SLAB_STORE_USER)) - goto out; - - list_for_each_entry(slab, &n->full, slab_list) { - validate_slab(s, slab, obj_map); - count++; - } - if (count != atomic_long_read(&n->nr_slabs)) { - pr_err("SLUB: %s %ld slabs counted but counter=%ld\n", - s->name, count, atomic_long_read(&n->nr_slabs)); - slab_add_kunit_errors(); - } - -out: - spin_unlock_irqrestore(&n->list_lock, flags); - return count; -} - -long validate_slab_cache(struct kmem_cache *s) -{ - int node; - unsigned long count = 0; - struct kmem_cache_node *n; - unsigned long *obj_map; - - obj_map = bitmap_alloc(oo_objects(s->oo), GFP_KERNEL); - if (!obj_map) - return -ENOMEM; - - flush_all(s); - for_each_kmem_cache_node(s, node, n) - count += validate_slab_node(s, n, obj_map); - - bitmap_free(obj_map); - - return count; -} -EXPORT_SYMBOL(validate_slab_cache); - -#ifdef CONFIG_DEBUG_FS -/* - * Generate lists of code addresses where slabcache objects are allocated - * and freed. - */ - -struct location { - depot_stack_handle_t handle; - unsigned long count; - unsigned long addr; - unsigned long waste; - long long sum_time; - long min_time; - long max_time; - long min_pid; - long max_pid; - DECLARE_BITMAP(cpus, NR_CPUS); - nodemask_t nodes; -}; - -struct loc_track { - unsigned long max; - unsigned long count; - struct location *loc; - loff_t idx; -}; - -static struct dentry *slab_debugfs_root; - -static void free_loc_track(struct loc_track *t) -{ - if (t->max) - free_pages((unsigned long)t->loc, - get_order(sizeof(struct location) * t->max)); -} - -static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags) -{ - struct location *l; - int order; - - order = get_order(sizeof(struct location) * max); - - l = (void *)__get_free_pages(flags, order); - if (!l) - return 0; - - if (t->count) { - memcpy(l, t->loc, sizeof(struct location) * t->count); - free_loc_track(t); - } - t->max = max; - t->loc = l; - return 1; -} - -static int add_location(struct loc_track *t, struct kmem_cache *s, - const struct track *track, - unsigned int orig_size) -{ - long start, end, pos; - struct location *l; - unsigned long caddr, chandle, cwaste; - unsigned long age = jiffies - track->when; - depot_stack_handle_t handle = 0; - unsigned int waste = s->object_size - orig_size; - -#ifdef CONFIG_STACKDEPOT - handle = READ_ONCE(track->handle); -#endif - start = -1; - end = t->count; - - for ( ; ; ) { - pos = start + (end - start + 1) / 2; - - /* - * There is nothing at "end". If we end up there - * we need to add something to before end. - */ - if (pos == end) - break; - - l = &t->loc[pos]; - caddr = l->addr; - chandle = l->handle; - cwaste = l->waste; - if ((track->addr == caddr) && (handle == chandle) && - (waste == cwaste)) { - - l->count++; - if (track->when) { - l->sum_time += age; - if (age < l->min_time) - l->min_time = age; - if (age > l->max_time) - l->max_time = age; - - if (track->pid < l->min_pid) - l->min_pid = track->pid; - if (track->pid > l->max_pid) - l->max_pid = track->pid; - - cpumask_set_cpu(track->cpu, - to_cpumask(l->cpus)); - } - node_set(page_to_nid(virt_to_page(track)), l->nodes); - return 1; - } - - if (track->addr < caddr) - end = pos; - else if (track->addr == caddr && handle < chandle) - end = pos; - else if (track->addr == caddr && handle == chandle && - waste < cwaste) - end = pos; - else - start = pos; - } - - /* - * Not found. Insert new tracking element. - */ - if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC)) - return 0; - - l = t->loc + pos; - if (pos < t->count) - memmove(l + 1, l, - (t->count - pos) * sizeof(struct location)); - t->count++; - l->count = 1; - l->addr = track->addr; - l->sum_time = age; - l->min_time = age; - l->max_time = age; - l->min_pid = track->pid; - l->max_pid = track->pid; - l->handle = handle; - l->waste = waste; - cpumask_clear(to_cpumask(l->cpus)); - cpumask_set_cpu(track->cpu, to_cpumask(l->cpus)); - nodes_clear(l->nodes); - node_set(page_to_nid(virt_to_page(track)), l->nodes); - return 1; -} - -static void process_slab(struct loc_track *t, struct kmem_cache *s, - struct slab *slab, enum track_item alloc, - unsigned long *obj_map) -{ - void *addr = slab_address(slab); - bool is_alloc = (alloc == TRACK_ALLOC); - void *p; - - __fill_map(obj_map, s, slab); - - for_each_object(p, s, addr, slab->objects) - if (!test_bit(__obj_to_index(s, addr, p), obj_map)) - add_location(t, s, get_track(s, p, alloc), - is_alloc ? get_orig_size(s, p) : - s->object_size); -} -#endif /* CONFIG_DEBUG_FS */ -#endif /* CONFIG_SLUB_DEBUG */ - -#ifdef SLAB_SUPPORTS_SYSFS -enum slab_stat_type { - SL_ALL, /* All slabs */ - SL_PARTIAL, /* Only partially allocated slabs */ - SL_CPU, /* Only slabs used for cpu caches */ - SL_OBJECTS, /* Determine allocated objects not slabs */ - SL_TOTAL /* Determine object capacity not slabs */ -}; - -#define SO_ALL (1 << SL_ALL) -#define SO_PARTIAL (1 << SL_PARTIAL) -#define SO_CPU (1 << SL_CPU) -#define SO_OBJECTS (1 << SL_OBJECTS) -#define SO_TOTAL (1 << SL_TOTAL) - -static ssize_t show_slab_objects(struct kmem_cache *s, - char *buf, unsigned long flags) -{ - unsigned long total = 0; - int node; - int x; - unsigned long *nodes; - int len = 0; - - nodes = kcalloc(nr_node_ids, sizeof(unsigned long), GFP_KERNEL); - if (!nodes) - return -ENOMEM; - - if (flags & SO_CPU) { - int cpu; - - for_each_possible_cpu(cpu) { - struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, - cpu); - int node; - struct slab *slab; - - slab = READ_ONCE(c->slab); - if (!slab) - continue; - - node = slab_nid(slab); - if (flags & SO_TOTAL) - x = slab->objects; - else if (flags & SO_OBJECTS) - x = slab->inuse; - else - x = 1; - - total += x; - nodes[node] += x; - -#ifdef CONFIG_SLUB_CPU_PARTIAL - slab = slub_percpu_partial_read_once(c); - if (slab) { - node = slab_nid(slab); - if (flags & SO_TOTAL) - WARN_ON_ONCE(1); - else if (flags & SO_OBJECTS) - WARN_ON_ONCE(1); - else - x = slab->slabs; - total += x; - nodes[node] += x; - } -#endif - } - } - - /* - * It is impossible to take "mem_hotplug_lock" here with "kernfs_mutex" - * already held which will conflict with an existing lock order: - * - * mem_hotplug_lock->slab_mutex->kernfs_mutex - * - * We don't really need mem_hotplug_lock (to hold off - * slab_mem_going_offline_callback) here because slab's memory hot - * unplug code doesn't destroy the kmem_cache->node[] data. - */ - -#ifdef CONFIG_SLUB_DEBUG - if (flags & SO_ALL) { - struct kmem_cache_node *n; - - for_each_kmem_cache_node(s, node, n) { - - if (flags & SO_TOTAL) - x = atomic_long_read(&n->total_objects); - else if (flags & SO_OBJECTS) - x = atomic_long_read(&n->total_objects) - - count_partial(n, count_free); - else - x = atomic_long_read(&n->nr_slabs); - total += x; - nodes[node] += x; - } - - } else -#endif - if (flags & SO_PARTIAL) { - struct kmem_cache_node *n; - - for_each_kmem_cache_node(s, node, n) { - if (flags & SO_TOTAL) - x = count_partial(n, count_total); - else if (flags & SO_OBJECTS) - x = count_partial(n, count_inuse); - else - x = n->nr_partial; - total += x; - nodes[node] += x; - } - } - - len += sysfs_emit_at(buf, len, "%lu", total); -#ifdef CONFIG_NUMA - for (node = 0; node < nr_node_ids; node++) { - if (nodes[node]) - len += sysfs_emit_at(buf, len, " N%d=%lu", - node, nodes[node]); - } -#endif - len += sysfs_emit_at(buf, len, "\n"); - kfree(nodes); - - return len; -} - -#define to_slab_attr(n) container_of(n, struct slab_attribute, attr) -#define to_slab(n) container_of(n, struct kmem_cache, kobj) - -struct slab_attribute { - struct attribute attr; - ssize_t (*show)(struct kmem_cache *s, char *buf); - ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count); -}; - -#define SLAB_ATTR_RO(_name) \ - static struct slab_attribute _name##_attr = __ATTR_RO_MODE(_name, 0400) - -#define SLAB_ATTR(_name) \ - static struct slab_attribute _name##_attr = __ATTR_RW_MODE(_name, 0600) - -static ssize_t slab_size_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%u\n", s->size); -} -SLAB_ATTR_RO(slab_size); - -static ssize_t align_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%u\n", s->align); -} -SLAB_ATTR_RO(align); - -static ssize_t object_size_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%u\n", s->object_size); -} -SLAB_ATTR_RO(object_size); - -static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%u\n", oo_objects(s->oo)); -} -SLAB_ATTR_RO(objs_per_slab); - -static ssize_t order_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%u\n", oo_order(s->oo)); -} -SLAB_ATTR_RO(order); - -static ssize_t min_partial_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%lu\n", s->min_partial); -} - -static ssize_t min_partial_store(struct kmem_cache *s, const char *buf, - size_t length) -{ - unsigned long min; - int err; - - err = kstrtoul(buf, 10, &min); - if (err) - return err; - - s->min_partial = min; - return length; -} -SLAB_ATTR(min_partial); - -static ssize_t cpu_partial_show(struct kmem_cache *s, char *buf) -{ - unsigned int nr_partial = 0; -#ifdef CONFIG_SLUB_CPU_PARTIAL - nr_partial = s->cpu_partial; -#endif - - return sysfs_emit(buf, "%u\n", nr_partial); -} - -static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf, - size_t length) -{ - unsigned int objects; - int err; - - err = kstrtouint(buf, 10, &objects); - if (err) - return err; - if (objects && !kmem_cache_has_cpu_partial(s)) - return -EINVAL; - - slub_set_cpu_partial(s, objects); - flush_all(s); - return length; -} -SLAB_ATTR(cpu_partial); - -static ssize_t ctor_show(struct kmem_cache *s, char *buf) -{ - if (!s->ctor) - return 0; - return sysfs_emit(buf, "%pS\n", s->ctor); -} -SLAB_ATTR_RO(ctor); - -static ssize_t aliases_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%d\n", s->refcount < 0 ? 0 : s->refcount - 1); -} -SLAB_ATTR_RO(aliases); - -static ssize_t partial_show(struct kmem_cache *s, char *buf) -{ - return show_slab_objects(s, buf, SO_PARTIAL); -} -SLAB_ATTR_RO(partial); - -static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf) -{ - return show_slab_objects(s, buf, SO_CPU); -} -SLAB_ATTR_RO(cpu_slabs); - -static ssize_t objects_show(struct kmem_cache *s, char *buf) -{ - return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS); -} -SLAB_ATTR_RO(objects); - -static ssize_t objects_partial_show(struct kmem_cache *s, char *buf) -{ - return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS); -} -SLAB_ATTR_RO(objects_partial); - -static ssize_t slabs_cpu_partial_show(struct kmem_cache *s, char *buf) -{ - int objects = 0; - int slabs = 0; - int cpu __maybe_unused; - int len = 0; - -#ifdef CONFIG_SLUB_CPU_PARTIAL - for_each_online_cpu(cpu) { - struct slab *slab; - - slab = slub_percpu_partial(per_cpu_ptr(s->cpu_slab, cpu)); - - if (slab) - slabs += slab->slabs; - } -#endif - - /* Approximate half-full slabs, see slub_set_cpu_partial() */ - objects = (slabs * oo_objects(s->oo)) / 2; - len += sysfs_emit_at(buf, len, "%d(%d)", objects, slabs); - -#if defined(CONFIG_SLUB_CPU_PARTIAL) && defined(CONFIG_SMP) - for_each_online_cpu(cpu) { - struct slab *slab; - - slab = slub_percpu_partial(per_cpu_ptr(s->cpu_slab, cpu)); - if (slab) { - slabs = READ_ONCE(slab->slabs); - objects = (slabs * oo_objects(s->oo)) / 2; - len += sysfs_emit_at(buf, len, " C%d=%d(%d)", - cpu, objects, slabs); - } - } -#endif - len += sysfs_emit_at(buf, len, "\n"); - - return len; -} -SLAB_ATTR_RO(slabs_cpu_partial); - -static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT)); -} -SLAB_ATTR_RO(reclaim_account); - -static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN)); -} -SLAB_ATTR_RO(hwcache_align); - -#ifdef CONFIG_ZONE_DMA -static ssize_t cache_dma_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA)); -} -SLAB_ATTR_RO(cache_dma); -#endif - -#ifdef CONFIG_HARDENED_USERCOPY -static ssize_t usersize_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%u\n", s->usersize); -} -SLAB_ATTR_RO(usersize); -#endif - -static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_TYPESAFE_BY_RCU)); -} -SLAB_ATTR_RO(destroy_by_rcu); - -#ifdef CONFIG_SLUB_DEBUG -static ssize_t slabs_show(struct kmem_cache *s, char *buf) -{ - return show_slab_objects(s, buf, SO_ALL); -} -SLAB_ATTR_RO(slabs); - -static ssize_t total_objects_show(struct kmem_cache *s, char *buf) -{ - return show_slab_objects(s, buf, SO_ALL|SO_TOTAL); -} -SLAB_ATTR_RO(total_objects); - -static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_CONSISTENCY_CHECKS)); -} -SLAB_ATTR_RO(sanity_checks); - -static ssize_t trace_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_TRACE)); -} -SLAB_ATTR_RO(trace); - -static ssize_t red_zone_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE)); -} - -SLAB_ATTR_RO(red_zone); - -static ssize_t poison_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_POISON)); -} - -SLAB_ATTR_RO(poison); - -static ssize_t store_user_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_STORE_USER)); -} - -SLAB_ATTR_RO(store_user); - -static ssize_t validate_show(struct kmem_cache *s, char *buf) -{ - return 0; -} - -static ssize_t validate_store(struct kmem_cache *s, - const char *buf, size_t length) -{ - int ret = -EINVAL; - - if (buf[0] == '1' && kmem_cache_debug(s)) { - ret = validate_slab_cache(s); - if (ret >= 0) - ret = length; - } - return ret; -} -SLAB_ATTR(validate); - -#endif /* CONFIG_SLUB_DEBUG */ - -#ifdef CONFIG_FAILSLAB -static ssize_t failslab_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB)); -} - -static ssize_t failslab_store(struct kmem_cache *s, const char *buf, - size_t length) -{ - if (s->refcount > 1) - return -EINVAL; - - if (buf[0] == '1') - WRITE_ONCE(s->flags, s->flags | SLAB_FAILSLAB); - else - WRITE_ONCE(s->flags, s->flags & ~SLAB_FAILSLAB); - - return length; -} -SLAB_ATTR(failslab); -#endif - -static ssize_t shrink_show(struct kmem_cache *s, char *buf) -{ - return 0; -} - -static ssize_t shrink_store(struct kmem_cache *s, - const char *buf, size_t length) -{ - if (buf[0] == '1') - kmem_cache_shrink(s); - else - return -EINVAL; - return length; -} -SLAB_ATTR(shrink); - -#ifdef CONFIG_NUMA -static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%u\n", s->remote_node_defrag_ratio / 10); -} - -static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s, - const char *buf, size_t length) -{ - unsigned int ratio; - int err; - - err = kstrtouint(buf, 10, &ratio); - if (err) - return err; - if (ratio > 100) - return -ERANGE; - - s->remote_node_defrag_ratio = ratio * 10; - - return length; -} -SLAB_ATTR(remote_node_defrag_ratio); -#endif - -#ifdef CONFIG_SLUB_STATS -static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si) -{ - unsigned long sum = 0; - int cpu; - int len = 0; - int *data = kmalloc_array(nr_cpu_ids, sizeof(int), GFP_KERNEL); - - if (!data) - return -ENOMEM; - - for_each_online_cpu(cpu) { - unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si]; - - data[cpu] = x; - sum += x; - } - - len += sysfs_emit_at(buf, len, "%lu", sum); - -#ifdef CONFIG_SMP - for_each_online_cpu(cpu) { - if (data[cpu]) - len += sysfs_emit_at(buf, len, " C%d=%u", - cpu, data[cpu]); - } -#endif - kfree(data); - len += sysfs_emit_at(buf, len, "\n"); - - return len; -} - -static void clear_stat(struct kmem_cache *s, enum stat_item si) -{ - int cpu; - - for_each_online_cpu(cpu) - per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0; -} - -#define STAT_ATTR(si, text) \ -static ssize_t text##_show(struct kmem_cache *s, char *buf) \ -{ \ - return show_stat(s, buf, si); \ -} \ -static ssize_t text##_store(struct kmem_cache *s, \ - const char *buf, size_t length) \ -{ \ - if (buf[0] != '0') \ - return -EINVAL; \ - clear_stat(s, si); \ - return length; \ -} \ -SLAB_ATTR(text); \ - -STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath); -STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath); -STAT_ATTR(FREE_FASTPATH, free_fastpath); -STAT_ATTR(FREE_SLOWPATH, free_slowpath); -STAT_ATTR(FREE_FROZEN, free_frozen); -STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial); -STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial); -STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial); -STAT_ATTR(ALLOC_SLAB, alloc_slab); -STAT_ATTR(ALLOC_REFILL, alloc_refill); -STAT_ATTR(ALLOC_NODE_MISMATCH, alloc_node_mismatch); -STAT_ATTR(FREE_SLAB, free_slab); -STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush); -STAT_ATTR(DEACTIVATE_FULL, deactivate_full); -STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty); -STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head); -STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail); -STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees); -STAT_ATTR(DEACTIVATE_BYPASS, deactivate_bypass); -STAT_ATTR(ORDER_FALLBACK, order_fallback); -STAT_ATTR(CMPXCHG_DOUBLE_CPU_FAIL, cmpxchg_double_cpu_fail); -STAT_ATTR(CMPXCHG_DOUBLE_FAIL, cmpxchg_double_fail); -STAT_ATTR(CPU_PARTIAL_ALLOC, cpu_partial_alloc); -STAT_ATTR(CPU_PARTIAL_FREE, cpu_partial_free); -STAT_ATTR(CPU_PARTIAL_NODE, cpu_partial_node); -STAT_ATTR(CPU_PARTIAL_DRAIN, cpu_partial_drain); -#endif /* CONFIG_SLUB_STATS */ - -#ifdef CONFIG_KFENCE -static ssize_t skip_kfence_show(struct kmem_cache *s, char *buf) -{ - return sysfs_emit(buf, "%d\n", !!(s->flags & SLAB_SKIP_KFENCE)); -} - -static ssize_t skip_kfence_store(struct kmem_cache *s, - const char *buf, size_t length) -{ - int ret = length; - - if (buf[0] == '0') - s->flags &= ~SLAB_SKIP_KFENCE; - else if (buf[0] == '1') - s->flags |= SLAB_SKIP_KFENCE; - else - ret = -EINVAL; - - return ret; -} -SLAB_ATTR(skip_kfence); -#endif - -static struct attribute *slab_attrs[] = { - &slab_size_attr.attr, - &object_size_attr.attr, - &objs_per_slab_attr.attr, - &order_attr.attr, - &min_partial_attr.attr, - &cpu_partial_attr.attr, - &objects_attr.attr, - &objects_partial_attr.attr, - &partial_attr.attr, - &cpu_slabs_attr.attr, - &ctor_attr.attr, - &aliases_attr.attr, - &align_attr.attr, - &hwcache_align_attr.attr, - &reclaim_account_attr.attr, - &destroy_by_rcu_attr.attr, - &shrink_attr.attr, - &slabs_cpu_partial_attr.attr, -#ifdef CONFIG_SLUB_DEBUG - &total_objects_attr.attr, - &slabs_attr.attr, - &sanity_checks_attr.attr, - &trace_attr.attr, - &red_zone_attr.attr, - &poison_attr.attr, - &store_user_attr.attr, - &validate_attr.attr, -#endif -#ifdef CONFIG_ZONE_DMA - &cache_dma_attr.attr, -#endif -#ifdef CONFIG_NUMA - &remote_node_defrag_ratio_attr.attr, -#endif -#ifdef CONFIG_SLUB_STATS - &alloc_fastpath_attr.attr, - &alloc_slowpath_attr.attr, - &free_fastpath_attr.attr, - &free_slowpath_attr.attr, - &free_frozen_attr.attr, - &free_add_partial_attr.attr, - &free_remove_partial_attr.attr, - &alloc_from_partial_attr.attr, - &alloc_slab_attr.attr, - &alloc_refill_attr.attr, - &alloc_node_mismatch_attr.attr, - &free_slab_attr.attr, - &cpuslab_flush_attr.attr, - &deactivate_full_attr.attr, - &deactivate_empty_attr.attr, - &deactivate_to_head_attr.attr, - &deactivate_to_tail_attr.attr, - &deactivate_remote_frees_attr.attr, - &deactivate_bypass_attr.attr, - &order_fallback_attr.attr, - &cmpxchg_double_fail_attr.attr, - &cmpxchg_double_cpu_fail_attr.attr, - &cpu_partial_alloc_attr.attr, - &cpu_partial_free_attr.attr, - &cpu_partial_node_attr.attr, - &cpu_partial_drain_attr.attr, -#endif -#ifdef CONFIG_FAILSLAB - &failslab_attr.attr, -#endif -#ifdef CONFIG_HARDENED_USERCOPY - &usersize_attr.attr, -#endif -#ifdef CONFIG_KFENCE - &skip_kfence_attr.attr, -#endif - - NULL -}; - -static const struct attribute_group slab_attr_group = { - .attrs = slab_attrs, -}; - -static ssize_t slab_attr_show(struct kobject *kobj, - struct attribute *attr, - char *buf) -{ - struct slab_attribute *attribute; - struct kmem_cache *s; - - attribute = to_slab_attr(attr); - s = to_slab(kobj); - - if (!attribute->show) - return -EIO; - - return attribute->show(s, buf); -} - -static ssize_t slab_attr_store(struct kobject *kobj, - struct attribute *attr, - const char *buf, size_t len) -{ - struct slab_attribute *attribute; - struct kmem_cache *s; - - attribute = to_slab_attr(attr); - s = to_slab(kobj); - - if (!attribute->store) - return -EIO; - - return attribute->store(s, buf, len); -} - -static void kmem_cache_release(struct kobject *k) -{ - slab_kmem_cache_release(to_slab(k)); -} - -static const struct sysfs_ops slab_sysfs_ops = { - .show = slab_attr_show, - .store = slab_attr_store, -}; - -static struct kobj_type slab_ktype = { - .sysfs_ops = &slab_sysfs_ops, - .release = kmem_cache_release, -}; - -static struct kset *slab_kset; - -static inline struct kset *cache_kset(struct kmem_cache *s) -{ - return slab_kset; -} - -#define ID_STR_LENGTH 32 - -/* Create a unique string id for a slab cache: - * - * Format :[flags-]size - */ -static char *create_unique_id(struct kmem_cache *s) -{ - char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL); - char *p = name; - - if (!name) - return ERR_PTR(-ENOMEM); - - *p++ = ':'; - /* - * First flags affecting slabcache operations. We will only - * get here for aliasable slabs so we do not need to support - * too many flags. The flags here must cover all flags that - * are matched during merging to guarantee that the id is - * unique. - */ - if (s->flags & SLAB_CACHE_DMA) - *p++ = 'd'; - if (s->flags & SLAB_CACHE_DMA32) - *p++ = 'D'; - if (s->flags & SLAB_RECLAIM_ACCOUNT) - *p++ = 'a'; - if (s->flags & SLAB_CONSISTENCY_CHECKS) - *p++ = 'F'; - if (s->flags & SLAB_ACCOUNT) - *p++ = 'A'; - if (p != name + 1) - *p++ = '-'; - p += snprintf(p, ID_STR_LENGTH - (p - name), "%07u", s->size); - - if (WARN_ON(p > name + ID_STR_LENGTH - 1)) { - kfree(name); - return ERR_PTR(-EINVAL); - } - kmsan_unpoison_memory(name, p - name); - return name; -} - -static int sysfs_slab_add(struct kmem_cache *s) -{ - int err; - const char *name; - struct kset *kset = cache_kset(s); - int unmergeable = slab_unmergeable(s); - - if (!unmergeable && disable_higher_order_debug && - (slub_debug & DEBUG_METADATA_FLAGS)) - unmergeable = 1; - - if (unmergeable) { - /* - * Slabcache can never be merged so we can use the name proper. - * This is typically the case for debug situations. In that - * case we can catch duplicate names easily. - */ - sysfs_remove_link(&slab_kset->kobj, s->name); - name = s->name; - } else { - /* - * Create a unique name for the slab as a target - * for the symlinks. - */ - name = create_unique_id(s); - if (IS_ERR(name)) - return PTR_ERR(name); - } - - s->kobj.kset = kset; - err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, "%s", name); - if (err) - goto out; - - err = sysfs_create_group(&s->kobj, &slab_attr_group); - if (err) - goto out_del_kobj; - - if (!unmergeable) { - /* Setup first alias */ - sysfs_slab_alias(s, s->name); - } -out: - if (!unmergeable) - kfree(name); - return err; -out_del_kobj: - kobject_del(&s->kobj); - goto out; -} - -void sysfs_slab_unlink(struct kmem_cache *s) -{ - if (slab_state >= FULL) - kobject_del(&s->kobj); -} - -void sysfs_slab_release(struct kmem_cache *s) -{ - if (slab_state >= FULL) - kobject_put(&s->kobj); -} - -/* - * Need to buffer aliases during bootup until sysfs becomes - * available lest we lose that information. - */ -struct saved_alias { - struct kmem_cache *s; - const char *name; - struct saved_alias *next; -}; - -static struct saved_alias *alias_list; - -static int sysfs_slab_alias(struct kmem_cache *s, const char *name) -{ - struct saved_alias *al; - - if (slab_state == FULL) { - /* - * If we have a leftover link then remove it. - */ - sysfs_remove_link(&slab_kset->kobj, name); - return sysfs_create_link(&slab_kset->kobj, &s->kobj, name); - } - - al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL); - if (!al) - return -ENOMEM; - - al->s = s; - al->name = name; - al->next = alias_list; - alias_list = al; - kmsan_unpoison_memory(al, sizeof(*al)); - return 0; -} - -static int __init slab_sysfs_init(void) -{ - struct kmem_cache *s; - int err; - - mutex_lock(&slab_mutex); - - slab_kset = kset_create_and_add("slab", NULL, kernel_kobj); - if (!slab_kset) { - mutex_unlock(&slab_mutex); - pr_err("Cannot register slab subsystem.\n"); - return -ENOSYS; - } - - slab_state = FULL; - - list_for_each_entry(s, &slab_caches, list) { - err = sysfs_slab_add(s); - if (err) - pr_err("SLUB: Unable to add boot slab %s to sysfs\n", - s->name); - } - - while (alias_list) { - struct saved_alias *al = alias_list; - - alias_list = alias_list->next; - err = sysfs_slab_alias(al->s, al->name); - if (err) - pr_err("SLUB: Unable to add boot slab alias %s to sysfs\n", - al->name); - kfree(al); - } - - mutex_unlock(&slab_mutex); - return 0; -} -late_initcall(slab_sysfs_init); -#endif /* SLAB_SUPPORTS_SYSFS */ - -#if defined(CONFIG_SLUB_DEBUG) && defined(CONFIG_DEBUG_FS) -static int slab_debugfs_show(struct seq_file *seq, void *v) -{ - struct loc_track *t = seq->private; - struct location *l; - unsigned long idx; - - idx = (unsigned long) t->idx; - if (idx < t->count) { - l = &t->loc[idx]; - - seq_printf(seq, "%7ld ", l->count); - - if (l->addr) - seq_printf(seq, "%pS", (void *)l->addr); - else - seq_puts(seq, "<not-available>"); - - if (l->waste) - seq_printf(seq, " waste=%lu/%lu", - l->count * l->waste, l->waste); - - if (l->sum_time != l->min_time) { - seq_printf(seq, " age=%ld/%llu/%ld", - l->min_time, div_u64(l->sum_time, l->count), - l->max_time); - } else - seq_printf(seq, " age=%ld", l->min_time); - - if (l->min_pid != l->max_pid) - seq_printf(seq, " pid=%ld-%ld", l->min_pid, l->max_pid); - else - seq_printf(seq, " pid=%ld", - l->min_pid); - - if (num_online_cpus() > 1 && !cpumask_empty(to_cpumask(l->cpus))) - seq_printf(seq, " cpus=%*pbl", - cpumask_pr_args(to_cpumask(l->cpus))); - - if (nr_online_nodes > 1 && !nodes_empty(l->nodes)) - seq_printf(seq, " nodes=%*pbl", - nodemask_pr_args(&l->nodes)); - -#ifdef CONFIG_STACKDEPOT - { - depot_stack_handle_t handle; - unsigned long *entries; - unsigned int nr_entries, j; - - handle = READ_ONCE(l->handle); - if (handle) { - nr_entries = stack_depot_fetch(handle, &entries); - seq_puts(seq, "\n"); - for (j = 0; j < nr_entries; j++) - seq_printf(seq, " %pS\n", (void *)entries[j]); - } - } -#endif - seq_puts(seq, "\n"); - } - - if (!idx && !t->count) - seq_puts(seq, "No data\n"); - - return 0; -} - -static void slab_debugfs_stop(struct seq_file *seq, void *v) -{ -} - -static void *slab_debugfs_next(struct seq_file *seq, void *v, loff_t *ppos) -{ - struct loc_track *t = seq->private; - - t->idx = ++(*ppos); - if (*ppos <= t->count) - return ppos; - - return NULL; -} - -static int cmp_loc_by_count(const void *a, const void *b, const void *data) -{ - struct location *loc1 = (struct location *)a; - struct location *loc2 = (struct location *)b; - - if (loc1->count > loc2->count) - return -1; - else - return 1; -} - -static void *slab_debugfs_start(struct seq_file *seq, loff_t *ppos) -{ - struct loc_track *t = seq->private; - - t->idx = *ppos; - return ppos; -} - -static const struct seq_operations slab_debugfs_sops = { - .start = slab_debugfs_start, - .next = slab_debugfs_next, - .stop = slab_debugfs_stop, - .show = slab_debugfs_show, -}; - -static int slab_debug_trace_open(struct inode *inode, struct file *filep) -{ - - struct kmem_cache_node *n; - enum track_item alloc; - int node; - struct loc_track *t = __seq_open_private(filep, &slab_debugfs_sops, - sizeof(struct loc_track)); - struct kmem_cache *s = file_inode(filep)->i_private; - unsigned long *obj_map; - - if (!t) - return -ENOMEM; - - obj_map = bitmap_alloc(oo_objects(s->oo), GFP_KERNEL); - if (!obj_map) { - seq_release_private(inode, filep); - return -ENOMEM; - } - - if (strcmp(filep->f_path.dentry->d_name.name, "alloc_traces") == 0) - alloc = TRACK_ALLOC; - else - alloc = TRACK_FREE; - - if (!alloc_loc_track(t, PAGE_SIZE / sizeof(struct location), GFP_KERNEL)) { - bitmap_free(obj_map); - seq_release_private(inode, filep); - return -ENOMEM; - } - - for_each_kmem_cache_node(s, node, n) { - unsigned long flags; - struct slab *slab; - - if (!atomic_long_read(&n->nr_slabs)) - continue; - - spin_lock_irqsave(&n->list_lock, flags); - list_for_each_entry(slab, &n->partial, slab_list) - process_slab(t, s, slab, alloc, obj_map); - list_for_each_entry(slab, &n->full, slab_list) - process_slab(t, s, slab, alloc, obj_map); - spin_unlock_irqrestore(&n->list_lock, flags); - } - - /* Sort locations by count */ - sort_r(t->loc, t->count, sizeof(struct location), - cmp_loc_by_count, NULL, NULL); - - bitmap_free(obj_map); - return 0; -} - -static int slab_debug_trace_release(struct inode *inode, struct file *file) -{ - struct seq_file *seq = file->private_data; - struct loc_track *t = seq->private; - - free_loc_track(t); - return seq_release_private(inode, file); -} - -static const struct file_operations slab_debugfs_fops = { - .open = slab_debug_trace_open, - .read = seq_read, - .llseek = seq_lseek, - .release = slab_debug_trace_release, -}; - -static void debugfs_slab_add(struct kmem_cache *s) -{ - struct dentry *slab_cache_dir; - - if (unlikely(!slab_debugfs_root)) - return; - - slab_cache_dir = debugfs_create_dir(s->name, slab_debugfs_root); - - debugfs_create_file("alloc_traces", 0400, - slab_cache_dir, s, &slab_debugfs_fops); - - debugfs_create_file("free_traces", 0400, - slab_cache_dir, s, &slab_debugfs_fops); -} - -void debugfs_slab_release(struct kmem_cache *s) -{ - debugfs_lookup_and_remove(s->name, slab_debugfs_root); -} - -static int __init slab_debugfs_init(void) -{ - struct kmem_cache *s; - - slab_debugfs_root = debugfs_create_dir("slab", NULL); - - list_for_each_entry(s, &slab_caches, list) - if (s->flags & SLAB_STORE_USER) - debugfs_slab_add(s); - - return 0; - -} -__initcall(slab_debugfs_init); -#endif -/* - * The /proc/slabinfo ABI - */ -#ifdef CONFIG_SLUB_DEBUG -void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo) -{ - unsigned long nr_slabs = 0; - unsigned long nr_objs = 0; - unsigned long nr_free = 0; - int node; - struct kmem_cache_node *n; - - for_each_kmem_cache_node(s, node, n) { - nr_slabs += node_nr_slabs(n); - nr_objs += node_nr_objs(n); - nr_free += count_partial(n, count_free); - } - - sinfo->active_objs = nr_objs - nr_free; - sinfo->num_objs = nr_objs; - sinfo->active_slabs = nr_slabs; - sinfo->num_slabs = nr_slabs; - sinfo->objects_per_slab = oo_objects(s->oo); - sinfo->cache_order = oo_order(s->oo); -} - -void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s) -{ -} - -ssize_t slabinfo_write(struct file *file, const char __user *buffer, - size_t count, loff_t *ppos) -{ - return -EIO; -} -#endif /* CONFIG_SLUB_DEBUG */