diff mbox series

[v3,17/19] mm: memcg/slab: use a single set of kmem_caches for all allocations

Message ID 20200422204708.2176080-18-guro@fb.com (mailing list archive)
State New, archived
Headers show
Series The new cgroup slab memory controller | expand

Commit Message

Roman Gushchin April 22, 2020, 8:47 p.m. UTC
Instead of having two sets of kmem_caches: one for system-wide and
non-accounted allocations and the second one shared by all accounted
allocations, we can use just one.

The idea is simple: space for obj_cgroup metadata can be allocated
on demand and filled only for accounted allocations.

It allows to remove a bunch of code which is required to handle
kmem_cache clones for accounted allocations. There is no more need
to create them, accumulate statistics, propagate attributes, etc.
It's a quite significant simplification.

Also, because the total number of slab_caches is reduced almost twice
(not all kmem_caches have a memcg clone), some additional memory
savings are expected. On my devvm it additionally saves about 3.5%
of slab memory.

Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Roman Gushchin <guro@fb.com>
---
 include/linux/slab.h     |   2 -
 include/linux/slab_def.h |   3 -
 include/linux/slub_def.h |   9 --
 mm/memcontrol.c          |   5 +-
 mm/slab.c                |   7 +-
 mm/slab.h                | 180 +++++++-----------------------
 mm/slab_common.c         | 230 +--------------------------------------
 mm/slub.c                | 126 +--------------------
 8 files changed, 55 insertions(+), 507 deletions(-)

Comments

Vlastimil Babka May 26, 2020, 2:55 p.m. UTC | #1
On 4/22/20 10:47 PM, Roman Gushchin wrote:
> Instead of having two sets of kmem_caches: one for system-wide and
> non-accounted allocations and the second one shared by all accounted
> allocations, we can use just one.
> 
> The idea is simple: space for obj_cgroup metadata can be allocated
> on demand and filled only for accounted allocations.
> 
> It allows to remove a bunch of code which is required to handle
> kmem_cache clones for accounted allocations. There is no more need
> to create them, accumulate statistics, propagate attributes, etc.
> It's a quite significant simplification.
> 
> Also, because the total number of slab_caches is reduced almost twice
> (not all kmem_caches have a memcg clone), some additional memory
> savings are expected. On my devvm it additionally saves about 3.5%
> of slab memory.
> 
> Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
> Signed-off-by: Roman Gushchin <guro@fb.com>

Reviewed-by: Vlastimil Babka <vbabka@suse.cz>

However, as this series will affect slab fastpaths, and perhaps especially this
patch will affect even non-kmemcg allocations being freed, I'm CCing Jesper and
Mel for awareness as they AFAIK did work on network stack memory management
performance, and perhaps some benchmarks are in order...
Jesper Dangaard Brouer May 27, 2020, 8:35 a.m. UTC | #2
On Tue, 26 May 2020 16:55:05 +0200
Vlastimil Babka <vbabka@suse.cz> wrote:

> On 4/22/20 10:47 PM, Roman Gushchin wrote:
> > Instead of having two sets of kmem_caches: one for system-wide and
> > non-accounted allocations and the second one shared by all accounted
> > allocations, we can use just one.
> > 
> > The idea is simple: space for obj_cgroup metadata can be allocated
> > on demand and filled only for accounted allocations.
> > 
> > It allows to remove a bunch of code which is required to handle
> > kmem_cache clones for accounted allocations. There is no more need
> > to create them, accumulate statistics, propagate attributes, etc.
> > It's a quite significant simplification.
> > 
> > Also, because the total number of slab_caches is reduced almost twice
> > (not all kmem_caches have a memcg clone), some additional memory
> > savings are expected. On my devvm it additionally saves about 3.5%
> > of slab memory.
> > 
> > Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
> > Signed-off-by: Roman Gushchin <guro@fb.com>  
> 
> Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
> 
> However, as this series will affect slab fastpaths, and perhaps
> especially this patch will affect even non-kmemcg allocations being
> freed, I'm CCing Jesper and Mel for awareness as they AFAIK did work
> on network stack memory management performance, and perhaps some
> benchmarks are in order...

Thanks for the heads-up! 

We (should) all know Mel Gorman's tests, which is here[1]:
 [1] https://github.com/gormanm/mmtests

My guess is that these change will only be visible with micro
benchmarks of the slub/slab.  I my slab/slub micro benchmarks are
located here [2] https://github.com/netoptimizer/prototype-kernel/

It is kernel modules that is compiled against your devel tree and pushed
to the remote host.  Results are simply printk'ed in dmesg.
Usage compile+push commands documented here[3]:
 [3] https://prototype-kernel.readthedocs.io/en/latest/prototype-kernel/build-process.html

I recommend trying: "slab_bulk_test01"
 modprobe slab_bulk_test01; rmmod slab_bulk_test01
 dmesg

Result from these kernel module benchmarks are included in some
commits[4][5]. And in [4] I found some overhead caused by MEMCG.

 [4] https://git.kernel.org/torvalds/c/ca257195511d
 [5] https://git.kernel.org/torvalds/c/fbd02630c6e3
diff mbox series

Patch

diff --git a/include/linux/slab.h b/include/linux/slab.h
index 310768bfa8d2..694a4f69e146 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -155,8 +155,6 @@  struct kmem_cache *kmem_cache_create_usercopy(const char *name,
 void kmem_cache_destroy(struct kmem_cache *);
 int kmem_cache_shrink(struct kmem_cache *);
 
-void memcg_create_kmem_cache(struct kmem_cache *cachep);
-
 /*
  * Please use this macro to create slab caches. Simply specify the
  * name of the structure and maybe some flags that are listed above.
diff --git a/include/linux/slab_def.h b/include/linux/slab_def.h
index 967a9a525eab..73f9308e98e3 100644
--- a/include/linux/slab_def.h
+++ b/include/linux/slab_def.h
@@ -72,9 +72,6 @@  struct kmem_cache {
 	int obj_offset;
 #endif /* CONFIG_DEBUG_SLAB */
 
-#ifdef CONFIG_MEMCG
-	struct memcg_cache_params memcg_params;
-#endif
 #ifdef CONFIG_KASAN
 	struct kasan_cache kasan_info;
 #endif
diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
index cbda7d55796a..cdf4f299c982 100644
--- a/include/linux/slub_def.h
+++ b/include/linux/slub_def.h
@@ -110,15 +110,6 @@  struct kmem_cache {
 	struct kobject kobj;	/* For sysfs */
 	struct work_struct kobj_remove_work;
 #endif
-#ifdef CONFIG_MEMCG
-	struct memcg_cache_params memcg_params;
-	/* For propagation, maximum size of a stored attr */
-	unsigned int max_attr_size;
-#ifdef CONFIG_SYSFS
-	struct kset *memcg_kset;
-#endif
-#endif
-
 #ifdef CONFIG_SLAB_FREELIST_HARDENED
 	unsigned long random;
 #endif
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index bd58b91631f7..4af95739ccb6 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2824,7 +2824,10 @@  struct mem_cgroup *mem_cgroup_from_obj(void *p)
 
 		off = obj_to_index(page->slab_cache, page, p);
 		objcg = page_obj_cgroups(page)[off];
-		return obj_cgroup_memcg(objcg);
+		if (objcg)
+			return obj_cgroup_memcg(objcg);
+
+		return NULL;
 	}
 
 	/* All other pages use page->mem_cgroup */
diff --git a/mm/slab.c b/mm/slab.c
index 5e933f5e24db..181ce8665d55 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1369,12 +1369,7 @@  static struct page *kmem_getpages(struct kmem_cache *cachep, gfp_t flags,
 		return NULL;
 	}
 
-	if (charge_slab_page(page, flags, cachep->gfporder, cachep,
-			     cachep->num)) {
-		__free_pages(page, cachep->gfporder);
-		return NULL;
-	}
-
+	charge_slab_page(page, flags, cachep->gfporder, cachep, cachep->num);
 	__SetPageSlab(page);
 	/* Record if ALLOC_NO_WATERMARKS was set when allocating the slab */
 	if (sk_memalloc_socks() && page_is_pfmemalloc(page))
diff --git a/mm/slab.h b/mm/slab.h
index 2958ca8d3159..13fadf33be5c 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -30,28 +30,6 @@  struct kmem_cache {
 	struct list_head list;	/* List of all slab caches on the system */
 };
 
-#else /* !CONFIG_SLOB */
-
-/*
- * This is the main placeholder for memcg-related information in kmem caches.
- * Both the root cache and the child cache will have it. Some fields are used
- * in both cases, other are specific to root caches.
- *
- * @root_cache:	Common to root and child caches.  NULL for root, pointer to
- *		the root cache for children.
- *
- * The following fields are specific to root caches.
- *
- * @memcg_cache: pointer to memcg kmem cache, used by all non-root memory
- *		cgroups.
- * @work: work struct used to create the non-root cache.
- */
-struct memcg_cache_params {
-	struct kmem_cache *root_cache;
-
-	struct kmem_cache *memcg_cache;
-	struct work_struct work;
-};
 #endif /* CONFIG_SLOB */
 
 #ifdef CONFIG_SLAB
@@ -194,7 +172,6 @@  int __kmem_cache_shutdown(struct kmem_cache *);
 void __kmem_cache_release(struct kmem_cache *);
 int __kmem_cache_shrink(struct kmem_cache *);
 void slab_kmem_cache_release(struct kmem_cache *);
-void kmem_cache_shrink_all(struct kmem_cache *s);
 
 struct seq_file;
 struct file;
@@ -233,43 +210,6 @@  static inline int cache_vmstat_idx(struct kmem_cache *s)
 }
 
 #ifdef CONFIG_MEMCG_KMEM
-static inline bool is_root_cache(struct kmem_cache *s)
-{
-	return !s->memcg_params.root_cache;
-}
-
-static inline bool slab_equal_or_root(struct kmem_cache *s,
-				      struct kmem_cache *p)
-{
-	return p == s || p == s->memcg_params.root_cache;
-}
-
-/*
- * We use suffixes to the name in memcg because we can't have caches
- * created in the system with the same name. But when we print them
- * locally, better refer to them with the base name
- */
-static inline const char *cache_name(struct kmem_cache *s)
-{
-	if (!is_root_cache(s))
-		s = s->memcg_params.root_cache;
-	return s->name;
-}
-
-static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
-{
-	if (is_root_cache(s))
-		return s;
-	return s->memcg_params.root_cache;
-}
-
-static inline struct kmem_cache *memcg_cache(struct kmem_cache *s)
-{
-	if (is_root_cache(s))
-		return s->memcg_params.memcg_cache;
-	return NULL;
-}
-
 static inline struct obj_cgroup **page_obj_cgroups(struct page *page)
 {
 	/*
@@ -315,38 +255,25 @@  static inline size_t obj_full_size(struct kmem_cache *s)
 	return s->size + sizeof(struct obj_cgroup *);
 }
 
-static inline struct kmem_cache *memcg_slab_pre_alloc_hook(struct kmem_cache *s,
-						struct obj_cgroup **objcgp,
-						size_t objects, gfp_t flags)
+static inline struct obj_cgroup *memcg_slab_pre_alloc_hook(struct kmem_cache *s,
+							   size_t objects,
+							   gfp_t flags)
 {
-	struct kmem_cache *cachep;
 	struct obj_cgroup *objcg;
 
 	if (memcg_kmem_bypass())
-		return s;
-
-	cachep = READ_ONCE(s->memcg_params.memcg_cache);
-	if (unlikely(!cachep)) {
-		/*
-		 * If memcg cache does not exist yet, we schedule it's
-		 * asynchronous creation and let the current allocation
-		 * go through with the root cache.
-		 */
-		queue_work(system_wq, &s->memcg_params.work);
-		return s;
-	}
+		return NULL;
 
 	objcg = get_obj_cgroup_from_current();
 	if (!objcg)
-		return s;
+		return NULL;
 
 	if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s))) {
 		obj_cgroup_put(objcg);
-		cachep = NULL;
+		return NULL;
 	}
 
-	*objcgp = objcg;
-	return cachep;
+	return objcg;
 }
 
 static inline void mod_objcg_state(struct obj_cgroup *objcg,
@@ -365,15 +292,28 @@  static inline void mod_objcg_state(struct obj_cgroup *objcg,
 
 static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
 					      struct obj_cgroup *objcg,
-					      size_t size, void **p)
+					      gfp_t flags, size_t size,
+					      void **p)
 {
 	struct page *page;
 	unsigned long off;
 	size_t i;
 
+	if (!objcg)
+		return;
+
+	flags &= ~__GFP_ACCOUNT;
 	for (i = 0; i < size; i++) {
 		if (likely(p[i])) {
 			page = virt_to_head_page(p[i]);
+
+			if (!page_has_obj_cgroups(page) &&
+			    memcg_alloc_page_obj_cgroups(page, flags,
+							 objs_per_slab(s))) {
+				obj_cgroup_uncharge(objcg, obj_full_size(s));
+				continue;
+			}
+
 			off = obj_to_index(s, page, p[i]);
 			obj_cgroup_get(objcg);
 			page_obj_cgroups(page)[off] = objcg;
@@ -392,13 +332,19 @@  static inline void memcg_slab_free_hook(struct kmem_cache *s, struct page *page,
 	struct obj_cgroup *objcg;
 	unsigned int off;
 
-	if (!memcg_kmem_enabled() || is_root_cache(s))
+	if (!memcg_kmem_enabled())
+		return;
+
+	if (!page_has_obj_cgroups(page))
 		return;
 
 	off = obj_to_index(s, page, p);
 	objcg = page_obj_cgroups(page)[off];
 	page_obj_cgroups(page)[off] = NULL;
 
+	if (!objcg)
+		return;
+
 	obj_cgroup_uncharge(objcg, obj_full_size(s));
 	mod_objcg_state(objcg, page_pgdat(page), cache_vmstat_idx(s),
 			-obj_full_size(s));
@@ -406,35 +352,7 @@  static inline void memcg_slab_free_hook(struct kmem_cache *s, struct page *page,
 	obj_cgroup_put(objcg);
 }
 
-extern void slab_init_memcg_params(struct kmem_cache *);
-
 #else /* CONFIG_MEMCG_KMEM */
-static inline bool is_root_cache(struct kmem_cache *s)
-{
-	return true;
-}
-
-static inline bool slab_equal_or_root(struct kmem_cache *s,
-				      struct kmem_cache *p)
-{
-	return s == p;
-}
-
-static inline const char *cache_name(struct kmem_cache *s)
-{
-	return s->name;
-}
-
-static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
-{
-	return s;
-}
-
-static inline struct kmem_cache *memcg_cache(struct kmem_cache *s)
-{
-	return NULL;
-}
-
 static inline bool page_has_obj_cgroups(struct page *page)
 {
 	return false;
@@ -455,16 +373,17 @@  static inline void memcg_free_page_obj_cgroups(struct page *page)
 {
 }
 
-static inline struct kmem_cache *memcg_slab_pre_alloc_hook(struct kmem_cache *s,
-						struct obj_cgroup **objcgp,
-						size_t objects, gfp_t flags)
+static inline struct obj_cgroup *memcg_slab_pre_alloc_hook(struct kmem_cache *s,
+							   size_t objects,
+							   gfp_t flags)
 {
 	return NULL;
 }
 
 static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
 					      struct obj_cgroup *objcg,
-					      size_t size, void **p)
+					      gfp_t flags, size_t size,
+					      void **p)
 {
 }
 
@@ -472,11 +391,6 @@  static inline void memcg_slab_free_hook(struct kmem_cache *s, struct page *page,
 					void *p)
 {
 }
-
-static inline void slab_init_memcg_params(struct kmem_cache *s)
-{
-}
-
 #endif /* CONFIG_MEMCG_KMEM */
 
 static inline struct kmem_cache *virt_to_cache(const void *obj)
@@ -490,28 +404,18 @@  static inline struct kmem_cache *virt_to_cache(const void *obj)
 	return page->slab_cache;
 }
 
-static __always_inline int charge_slab_page(struct page *page,
-					    gfp_t gfp, int order,
-					    struct kmem_cache *s)
+static __always_inline void charge_slab_page(struct page *page,
+					     gfp_t gfp, int order,
+					     struct kmem_cache *s)
 {
-	if (!is_root_cache(s)) {
-		int ret;
-
-		ret = memcg_alloc_page_obj_cgroups(page, gfp, objs_per_slab(s));
-		if (ret)
-			return ret;
-	}
-
 	mod_node_page_state(page_pgdat(page), cache_vmstat_idx(s),
 			    PAGE_SIZE << order);
-	return 0;
 }
 
 static __always_inline void uncharge_slab_page(struct page *page, int order,
 					       struct kmem_cache *s)
 {
-	if (!is_root_cache(s))
-		memcg_free_page_obj_cgroups(page);
+	memcg_free_page_obj_cgroups(page);
 
 	mod_node_page_state(page_pgdat(page), cache_vmstat_idx(s),
 			    -(PAGE_SIZE << order));
@@ -525,8 +429,7 @@  static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
 	 * When kmemcg is not being used, both assignments should return the
 	 * same value. but we don't want to pay the assignment price in that
 	 * case. If it is not compiled in, the compiler should be smart enough
-	 * to not do even the assignment. In that case, slab_equal_or_root
-	 * will also be a constant.
+	 * to not do even the assignment.
 	 */
 	if (!memcg_kmem_enabled() &&
 	    !IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) &&
@@ -534,7 +437,7 @@  static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
 		return s;
 
 	cachep = virt_to_cache(x);
-	WARN_ONCE(cachep && !slab_equal_or_root(cachep, s),
+	WARN_ONCE(cachep && cachep != s,
 		  "%s: Wrong slab cache. %s but object is from %s\n",
 		  __func__, s->name, cachep->name);
 	return cachep;
@@ -586,7 +489,7 @@  static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s,
 
 	if (memcg_kmem_enabled() &&
 	    ((flags & __GFP_ACCOUNT) || (s->flags & SLAB_ACCOUNT)))
-		return memcg_slab_pre_alloc_hook(s, objcgp, size, flags);
+		*objcgp = memcg_slab_pre_alloc_hook(s, size, flags);
 
 	return s;
 }
@@ -605,8 +508,7 @@  static inline void slab_post_alloc_hook(struct kmem_cache *s,
 					 s->flags, flags);
 	}
 
-	if (!is_root_cache(s))
-		memcg_slab_post_alloc_hook(s, objcg, size, p);
+	memcg_slab_post_alloc_hook(s, objcg, flags, size, p);
 }
 
 #ifndef CONFIG_SLOB
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 52164ad0f197..7be382d45514 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -128,36 +128,6 @@  int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr,
 	return i;
 }
 
-#ifdef CONFIG_MEMCG_KMEM
-static void memcg_kmem_cache_create_func(struct work_struct *work)
-{
-	struct kmem_cache *cachep = container_of(work, struct kmem_cache,
-						 memcg_params.work);
-	memcg_create_kmem_cache(cachep);
-}
-
-void slab_init_memcg_params(struct kmem_cache *s)
-{
-	s->memcg_params.root_cache = NULL;
-	s->memcg_params.memcg_cache = NULL;
-	INIT_WORK(&s->memcg_params.work, memcg_kmem_cache_create_func);
-}
-
-static void init_memcg_params(struct kmem_cache *s,
-			      struct kmem_cache *root_cache)
-{
-	if (root_cache)
-		s->memcg_params.root_cache = root_cache;
-	else
-		slab_init_memcg_params(s);
-}
-#else
-static inline void init_memcg_params(struct kmem_cache *s,
-				     struct kmem_cache *root_cache)
-{
-}
-#endif /* CONFIG_MEMCG_KMEM */
-
 /*
  * Figure out what the alignment of the objects will be given a set of
  * flags, a user specified alignment and the size of the objects.
@@ -195,9 +165,6 @@  int slab_unmergeable(struct kmem_cache *s)
 	if (slab_nomerge || (s->flags & SLAB_NEVER_MERGE))
 		return 1;
 
-	if (!is_root_cache(s))
-		return 1;
-
 	if (s->ctor)
 		return 1;
 
@@ -284,7 +251,6 @@  static struct kmem_cache *create_cache(const char *name,
 	s->useroffset = useroffset;
 	s->usersize = usersize;
 
-	init_memcg_params(s, root_cache);
 	err = __kmem_cache_create(s, flags);
 	if (err)
 		goto out_free_cache;
@@ -342,7 +308,6 @@  kmem_cache_create_usercopy(const char *name,
 
 	get_online_cpus();
 	get_online_mems();
-	memcg_get_cache_ids();
 
 	mutex_lock(&slab_mutex);
 
@@ -392,7 +357,6 @@  kmem_cache_create_usercopy(const char *name,
 out_unlock:
 	mutex_unlock(&slab_mutex);
 
-	memcg_put_cache_ids();
 	put_online_mems();
 	put_online_cpus();
 
@@ -505,87 +469,6 @@  static int shutdown_cache(struct kmem_cache *s)
 	return 0;
 }
 
-#ifdef CONFIG_MEMCG_KMEM
-/*
- * memcg_create_kmem_cache - Create a cache for non-root memory cgroups.
- * @root_cache: The parent of the new cache.
- *
- * This function attempts to create a kmem cache that will serve allocation
- * requests going all non-root memory cgroups to @root_cache. The new cache
- * inherits properties from its parent.
- */
-void memcg_create_kmem_cache(struct kmem_cache *root_cache)
-{
-	struct kmem_cache *s = NULL;
-	char *cache_name;
-
-	get_online_cpus();
-	get_online_mems();
-
-	mutex_lock(&slab_mutex);
-
-	if (root_cache->memcg_params.memcg_cache)
-		goto out_unlock;
-
-	cache_name = kasprintf(GFP_KERNEL, "%s-memcg", root_cache->name);
-	if (!cache_name)
-		goto out_unlock;
-
-	s = create_cache(cache_name, root_cache->object_size,
-			 root_cache->align,
-			 root_cache->flags & CACHE_CREATE_MASK,
-			 root_cache->useroffset, root_cache->usersize,
-			 root_cache->ctor, root_cache);
-	/*
-	 * If we could not create a memcg cache, do not complain, because
-	 * that's not critical at all as we can always proceed with the root
-	 * cache.
-	 */
-	if (IS_ERR(s)) {
-		kfree(cache_name);
-		goto out_unlock;
-	}
-
-	/*
-	 * Since readers won't lock (see memcg_slab_pre_alloc_hook()), we need a
-	 * barrier here to ensure nobody will see the kmem_cache partially
-	 * initialized.
-	 */
-	smp_wmb();
-	root_cache->memcg_params.memcg_cache = s;
-
-out_unlock:
-	mutex_unlock(&slab_mutex);
-
-	put_online_mems();
-	put_online_cpus();
-}
-
-static int shutdown_memcg_caches(struct kmem_cache *s)
-{
-	BUG_ON(!is_root_cache(s));
-
-	if (s->memcg_params.memcg_cache)
-		WARN_ON(shutdown_cache(s->memcg_params.memcg_cache));
-
-	return 0;
-}
-
-static void cancel_memcg_cache_creation(struct kmem_cache *s)
-{
-	cancel_work_sync(&s->memcg_params.work);
-}
-#else
-static inline int shutdown_memcg_caches(struct kmem_cache *s)
-{
-	return 0;
-}
-
-static inline void cancel_memcg_cache_creation(struct kmem_cache *s)
-{
-}
-#endif /* CONFIG_MEMCG_KMEM */
-
 void slab_kmem_cache_release(struct kmem_cache *s)
 {
 	__kmem_cache_release(s);
@@ -600,8 +483,6 @@  void kmem_cache_destroy(struct kmem_cache *s)
 	if (unlikely(!s))
 		return;
 
-	cancel_memcg_cache_creation(s);
-
 	get_online_cpus();
 	get_online_mems();
 
@@ -611,10 +492,7 @@  void kmem_cache_destroy(struct kmem_cache *s)
 	if (s->refcount)
 		goto out_unlock;
 
-	err = shutdown_memcg_caches(s);
-	if (!err)
-		err = shutdown_cache(s);
-
+	err = shutdown_cache(s);
 	if (err) {
 		pr_err("kmem_cache_destroy %s: Slab cache still has objects\n",
 		       s->name);
@@ -651,33 +529,6 @@  int kmem_cache_shrink(struct kmem_cache *cachep)
 }
 EXPORT_SYMBOL(kmem_cache_shrink);
 
-/**
- * kmem_cache_shrink_all - shrink root and memcg caches
- * @s: The cache pointer
- */
-void kmem_cache_shrink_all(struct kmem_cache *s)
-{
-	struct kmem_cache *c;
-
-	if (!IS_ENABLED(CONFIG_MEMCG_KMEM) || !is_root_cache(s)) {
-		kmem_cache_shrink(s);
-		return;
-	}
-
-	get_online_cpus();
-	get_online_mems();
-	kasan_cache_shrink(s);
-	__kmem_cache_shrink(s);
-
-	c = memcg_cache(s);
-	if (c) {
-		kasan_cache_shrink(c);
-		__kmem_cache_shrink(c);
-	}
-	put_online_mems();
-	put_online_cpus();
-}
-
 bool slab_is_available(void)
 {
 	return slab_state >= UP;
@@ -706,8 +557,6 @@  void __init create_boot_cache(struct kmem_cache *s, const char *name,
 	s->useroffset = useroffset;
 	s->usersize = usersize;
 
-	slab_init_memcg_params(s);
-
 	err = __kmem_cache_create(s, flags);
 
 	if (err)
@@ -1081,25 +930,6 @@  void slab_stop(struct seq_file *m, void *p)
 	mutex_unlock(&slab_mutex);
 }
 
-static void
-memcg_accumulate_slabinfo(struct kmem_cache *s, struct slabinfo *info)
-{
-	struct kmem_cache *c;
-	struct slabinfo sinfo;
-
-	c = memcg_cache(s);
-	if (c) {
-		memset(&sinfo, 0, sizeof(sinfo));
-		get_slabinfo(c, &sinfo);
-
-		info->active_slabs += sinfo.active_slabs;
-		info->num_slabs += sinfo.num_slabs;
-		info->shared_avail += sinfo.shared_avail;
-		info->active_objs += sinfo.active_objs;
-		info->num_objs += sinfo.num_objs;
-	}
-}
-
 static void cache_show(struct kmem_cache *s, struct seq_file *m)
 {
 	struct slabinfo sinfo;
@@ -1107,10 +937,8 @@  static void cache_show(struct kmem_cache *s, struct seq_file *m)
 	memset(&sinfo, 0, sizeof(sinfo));
 	get_slabinfo(s, &sinfo);
 
-	memcg_accumulate_slabinfo(s, &sinfo);
-
 	seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d",
-		   cache_name(s), sinfo.active_objs, sinfo.num_objs, s->size,
+		   s->name, sinfo.active_objs, sinfo.num_objs, s->size,
 		   sinfo.objects_per_slab, (1 << sinfo.cache_order));
 
 	seq_printf(m, " : tunables %4u %4u %4u",
@@ -1127,8 +955,7 @@  static int slab_show(struct seq_file *m, void *p)
 
 	if (p == slab_caches.next)
 		print_slabinfo_header(m);
-	if (is_root_cache(s))
-		cache_show(s, m);
+	cache_show(s, m);
 	return 0;
 }
 
@@ -1153,13 +980,13 @@  void dump_unreclaimable_slab(void)
 	pr_info("Name                      Used          Total\n");
 
 	list_for_each_entry_safe(s, s2, &slab_caches, list) {
-		if (!is_root_cache(s) || (s->flags & SLAB_RECLAIM_ACCOUNT))
+		if (s->flags & SLAB_RECLAIM_ACCOUNT)
 			continue;
 
 		get_slabinfo(s, &sinfo);
 
 		if (sinfo.num_objs > 0)
-			pr_info("%-17s %10luKB %10luKB\n", cache_name(s),
+			pr_info("%-17s %10luKB %10luKB\n", s->name,
 				(sinfo.active_objs * s->size) / 1024,
 				(sinfo.num_objs * s->size) / 1024);
 	}
@@ -1218,53 +1045,6 @@  static int __init slab_proc_init(void)
 }
 module_init(slab_proc_init);
 
-#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_MEMCG_KMEM)
-/*
- * Display information about kmem caches that have memcg cache.
- */
-static int memcg_slabinfo_show(struct seq_file *m, void *unused)
-{
-	struct kmem_cache *s, *c;
-	struct slabinfo sinfo;
-
-	mutex_lock(&slab_mutex);
-	seq_puts(m, "# <name> <css_id[:dead|deact]> <active_objs> <num_objs>");
-	seq_puts(m, " <active_slabs> <num_slabs>\n");
-	list_for_each_entry(s, &slab_caches, list) {
-		/*
-		 * Skip kmem caches that don't have the memcg cache.
-		 */
-		if (!s->memcg_params.memcg_cache)
-			continue;
-
-		memset(&sinfo, 0, sizeof(sinfo));
-		get_slabinfo(s, &sinfo);
-		seq_printf(m, "%-17s root       %6lu %6lu %6lu %6lu\n",
-			   cache_name(s), sinfo.active_objs, sinfo.num_objs,
-			   sinfo.active_slabs, sinfo.num_slabs);
-
-		c = s->memcg_params.memcg_cache;
-		memset(&sinfo, 0, sizeof(sinfo));
-		get_slabinfo(c, &sinfo);
-		seq_printf(m, "%-17s %4d %6lu %6lu %6lu %6lu\n",
-			   cache_name(c), root_mem_cgroup->css.id,
-			   sinfo.active_objs, sinfo.num_objs,
-			   sinfo.active_slabs, sinfo.num_slabs);
-	}
-	mutex_unlock(&slab_mutex);
-	return 0;
-}
-DEFINE_SHOW_ATTRIBUTE(memcg_slabinfo);
-
-static int __init memcg_slabinfo_init(void)
-{
-	debugfs_create_file("memcg_slabinfo", S_IFREG | S_IRUGO,
-			    NULL, NULL, &memcg_slabinfo_fops);
-	return 0;
-}
-
-late_initcall(memcg_slabinfo_init);
-#endif /* CONFIG_DEBUG_FS && CONFIG_MEMCG_KMEM */
 #endif /* CONFIG_SLAB || CONFIG_SLUB_DEBUG */
 
 static __always_inline void *__do_krealloc(const void *p, size_t new_size,
diff --git a/mm/slub.c b/mm/slub.c
index 799082723e77..d875bab1626a 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -214,13 +214,11 @@  enum track_item { TRACK_ALLOC, TRACK_FREE };
 #ifdef CONFIG_SYSFS
 static int sysfs_slab_add(struct kmem_cache *);
 static int sysfs_slab_alias(struct kmem_cache *, const char *);
-static void memcg_propagate_slab_attrs(struct kmem_cache *s);
 static void sysfs_slab_remove(struct kmem_cache *s);
 #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; }
-static inline void memcg_propagate_slab_attrs(struct kmem_cache *s) { }
 static inline void sysfs_slab_remove(struct kmem_cache *s) { }
 #endif
 
@@ -1536,10 +1534,8 @@  static inline struct page *alloc_slab_page(struct kmem_cache *s,
 	else
 		page = __alloc_pages_node(node, flags, order);
 
-	if (page && charge_slab_page(page, flags, order, s)) {
-		__free_pages(page, order);
-		page = NULL;
-	}
+	if (page)
+		charge_slab_page(page, flags, order, s);
 
 	return page;
 }
@@ -4271,7 +4267,6 @@  static struct kmem_cache * __init bootstrap(struct kmem_cache *static_cache)
 			p->slab_cache = s;
 #endif
 	}
-	slab_init_memcg_params(s);
 	list_add(&s->list, &slab_caches);
 	return s;
 }
@@ -4327,7 +4322,7 @@  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, *c;
+	struct kmem_cache *s;
 
 	s = find_mergeable(size, align, flags, name, ctor);
 	if (s) {
@@ -4340,12 +4335,6 @@  __kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
 		s->object_size = max(s->object_size, size);
 		s->inuse = max(s->inuse, ALIGN(size, sizeof(void *)));
 
-		c = memcg_cache(s);
-		if (c) {
-			c->object_size = s->object_size;
-			c->inuse = max(c->inuse, ALIGN(size, sizeof(void *)));
-		}
-
 		if (sysfs_slab_alias(s, name)) {
 			s->refcount--;
 			s = NULL;
@@ -4367,7 +4356,6 @@  int __kmem_cache_create(struct kmem_cache *s, slab_flags_t flags)
 	if (slab_state <= UP)
 		return 0;
 
-	memcg_propagate_slab_attrs(s);
 	err = sysfs_slab_add(s);
 	if (err)
 		__kmem_cache_release(s);
@@ -5347,7 +5335,7 @@  static ssize_t shrink_store(struct kmem_cache *s,
 			const char *buf, size_t length)
 {
 	if (buf[0] == '1')
-		kmem_cache_shrink_all(s);
+		kmem_cache_shrink(s);
 	else
 		return -EINVAL;
 	return length;
@@ -5571,98 +5559,9 @@  static ssize_t slab_attr_store(struct kobject *kobj,
 		return -EIO;
 
 	err = attribute->store(s, buf, len);
-#ifdef CONFIG_MEMCG
-	if (slab_state >= FULL && err >= 0 && is_root_cache(s)) {
-		struct kmem_cache *c;
-
-		mutex_lock(&slab_mutex);
-		if (s->max_attr_size < len)
-			s->max_attr_size = len;
-
-		/*
-		 * This is a best effort propagation, so this function's return
-		 * value will be determined by the parent cache only. This is
-		 * basically because not all attributes will have a well
-		 * defined semantics for rollbacks - most of the actions will
-		 * have permanent effects.
-		 *
-		 * Returning the error value of any of the children that fail
-		 * is not 100 % defined, in the sense that users seeing the
-		 * error code won't be able to know anything about the state of
-		 * the cache.
-		 *
-		 * Only returning the error code for the parent cache at least
-		 * has well defined semantics. The cache being written to
-		 * directly either failed or succeeded, in which case we loop
-		 * through the descendants with best-effort propagation.
-		 */
-		c = memcg_cache(s);
-		if (c)
-			attribute->store(c, buf, len);
-		mutex_unlock(&slab_mutex);
-	}
-#endif
 	return err;
 }
 
-static void memcg_propagate_slab_attrs(struct kmem_cache *s)
-{
-#ifdef CONFIG_MEMCG
-	int i;
-	char *buffer = NULL;
-	struct kmem_cache *root_cache;
-
-	if (is_root_cache(s))
-		return;
-
-	root_cache = s->memcg_params.root_cache;
-
-	/*
-	 * This mean this cache had no attribute written. Therefore, no point
-	 * in copying default values around
-	 */
-	if (!root_cache->max_attr_size)
-		return;
-
-	for (i = 0; i < ARRAY_SIZE(slab_attrs); i++) {
-		char mbuf[64];
-		char *buf;
-		struct slab_attribute *attr = to_slab_attr(slab_attrs[i]);
-		ssize_t len;
-
-		if (!attr || !attr->store || !attr->show)
-			continue;
-
-		/*
-		 * It is really bad that we have to allocate here, so we will
-		 * do it only as a fallback. If we actually allocate, though,
-		 * we can just use the allocated buffer until the end.
-		 *
-		 * Most of the slub attributes will tend to be very small in
-		 * size, but sysfs allows buffers up to a page, so they can
-		 * theoretically happen.
-		 */
-		if (buffer)
-			buf = buffer;
-		else if (root_cache->max_attr_size < ARRAY_SIZE(mbuf))
-			buf = mbuf;
-		else {
-			buffer = (char *) get_zeroed_page(GFP_KERNEL);
-			if (WARN_ON(!buffer))
-				continue;
-			buf = buffer;
-		}
-
-		len = attr->show(root_cache, buf);
-		if (len > 0)
-			attr->store(s, buf, len);
-	}
-
-	if (buffer)
-		free_page((unsigned long)buffer);
-#endif	/* CONFIG_MEMCG */
-}
-
 static void kmem_cache_release(struct kobject *k)
 {
 	slab_kmem_cache_release(to_slab(k));
@@ -5695,10 +5594,6 @@  static struct kset *slab_kset;
 
 static inline struct kset *cache_kset(struct kmem_cache *s)
 {
-#ifdef CONFIG_MEMCG
-	if (!is_root_cache(s))
-		return s->memcg_params.root_cache->memcg_kset;
-#endif
 	return slab_kset;
 }
 
@@ -5755,9 +5650,6 @@  static void sysfs_slab_remove_workfn(struct work_struct *work)
 		 */
 		goto out;
 
-#ifdef CONFIG_MEMCG
-	kset_unregister(s->memcg_kset);
-#endif
 	kobject_uevent(&s->kobj, KOBJ_REMOVE);
 out:
 	kobject_put(&s->kobj);
@@ -5806,16 +5698,6 @@  static int sysfs_slab_add(struct kmem_cache *s)
 	if (err)
 		goto out_del_kobj;
 
-#ifdef CONFIG_MEMCG
-	if (is_root_cache(s) && memcg_sysfs_enabled) {
-		s->memcg_kset = kset_create_and_add("cgroup", NULL, &s->kobj);
-		if (!s->memcg_kset) {
-			err = -ENOMEM;
-			goto out_del_kobj;
-		}
-	}
-#endif
-
 	kobject_uevent(&s->kobj, KOBJ_ADD);
 	if (!unmergeable) {
 		/* Setup first alias */