| Message ID | 20230531154836.1366225-5-catalin.marinas@arm.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm, dma, arm64: Reduce ARCH_KMALLOC_MINALIGN to 8 | expand |
On 5/31/23 17:48, Catalin Marinas wrote: > Do not create kmalloc() caches which are not aligned to > dma_get_cache_alignment(). There is no functional change since for > current architectures defining ARCH_DMA_MINALIGN, ARCH_KMALLOC_MINALIGN > equals ARCH_DMA_MINALIGN (and dma_get_cache_alignment()). On > architectures without a specific ARCH_DMA_MINALIGN, > dma_get_cache_alignment() is 1, so no change to the kmalloc() caches. > > If an architecture selects ARCH_HAS_DMA_CACHE_LINE_SIZE (introduced > previously), the kmalloc() caches will be aligned to a cache line size. It this part leftover from a previous version? > Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: Christoph Hellwig <hch@lst.de> > Cc: Robin Murphy <robin.murphy@arm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> > --- > mm/slab_common.c | 24 +++++++++++++++++++++--- > 1 file changed, 21 insertions(+), 3 deletions(-) > > diff --git a/mm/slab_common.c b/mm/slab_common.c > index 7f069159aee2..7c6475847fdf 100644 > --- a/mm/slab_common.c > +++ b/mm/slab_common.c > @@ -17,6 +17,7 @@ > #include <linux/cpu.h> > #include <linux/uaccess.h> > #include <linux/seq_file.h> > +#include <linux/dma-mapping.h> > #include <linux/proc_fs.h> > #include <linux/debugfs.h> > #include <linux/kasan.h> > @@ -862,9 +863,18 @@ void __init setup_kmalloc_cache_index_table(void) > } > } > > +static unsigned int __kmalloc_minalign(void) > +{ > + return dma_get_cache_alignment(); > +} > + > void __init > new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags) > { > + unsigned int minalign = __kmalloc_minalign(); > + unsigned int aligned_size = kmalloc_info[idx].size; > + int aligned_idx = idx; > + > if ((KMALLOC_RECLAIM != KMALLOC_NORMAL) && (type == KMALLOC_RECLAIM)) { > flags |= SLAB_RECLAIM_ACCOUNT; > } else if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_CGROUP)) { > @@ -877,9 +887,17 @@ new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags) > flags |= SLAB_CACHE_DMA; > } > > - kmalloc_caches[type][idx] = create_kmalloc_cache( > - kmalloc_info[idx].name[type], > - kmalloc_info[idx].size, flags); > + if (minalign > ARCH_KMALLOC_MINALIGN) { > + aligned_size = ALIGN(aligned_size, minalign); > + aligned_idx = __kmalloc_index(aligned_size, false); > + } > + > + if (!kmalloc_caches[type][aligned_idx]) > + kmalloc_caches[type][aligned_idx] = create_kmalloc_cache( > + kmalloc_info[aligned_idx].name[type], > + aligned_size, flags); > + if (idx != aligned_idx) > + kmalloc_caches[type][idx] = kmalloc_caches[type][aligned_idx]; > > /* > * If CONFIG_MEMCG_KMEM is enabled, disable cache merging for >
diff --git a/mm/slab_common.c b/mm/slab_common.c index 7f069159aee2..7c6475847fdf 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -17,6 +17,7 @@ #include <linux/cpu.h> #include <linux/uaccess.h> #include <linux/seq_file.h> +#include <linux/dma-mapping.h> #include <linux/proc_fs.h> #include <linux/debugfs.h> #include <linux/kasan.h> @@ -862,9 +863,18 @@ void __init setup_kmalloc_cache_index_table(void) } } +static unsigned int __kmalloc_minalign(void) +{ + return dma_get_cache_alignment(); +} + void __init new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags) { + unsigned int minalign = __kmalloc_minalign(); + unsigned int aligned_size = kmalloc_info[idx].size; + int aligned_idx = idx; + if ((KMALLOC_RECLAIM != KMALLOC_NORMAL) && (type == KMALLOC_RECLAIM)) { flags |= SLAB_RECLAIM_ACCOUNT; } else if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_CGROUP)) { @@ -877,9 +887,17 @@ new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags) flags |= SLAB_CACHE_DMA; } - kmalloc_caches[type][idx] = create_kmalloc_cache( - kmalloc_info[idx].name[type], - kmalloc_info[idx].size, flags); + if (minalign > ARCH_KMALLOC_MINALIGN) { + aligned_size = ALIGN(aligned_size, minalign); + aligned_idx = __kmalloc_index(aligned_size, false); + } + + if (!kmalloc_caches[type][aligned_idx]) + kmalloc_caches[type][aligned_idx] = create_kmalloc_cache( + kmalloc_info[aligned_idx].name[type], + aligned_size, flags); + if (idx != aligned_idx) + kmalloc_caches[type][idx] = kmalloc_caches[type][aligned_idx]; /* * If CONFIG_MEMCG_KMEM is enabled, disable cache merging for
Do not create kmalloc() caches which are not aligned to dma_get_cache_alignment(). There is no functional change since for current architectures defining ARCH_DMA_MINALIGN, ARCH_KMALLOC_MINALIGN equals ARCH_DMA_MINALIGN (and dma_get_cache_alignment()). On architectures without a specific ARCH_DMA_MINALIGN, dma_get_cache_alignment() is 1, so no change to the kmalloc() caches. If an architecture selects ARCH_HAS_DMA_CACHE_LINE_SIZE (introduced previously), the kmalloc() caches will be aligned to a cache line size. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Robin Murphy <robin.murphy@arm.com> --- mm/slab_common.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-)