From c225150b86fef9f7663219b6e9f7606ea1607312 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Mon, 11 Jul 2011 13:35:08 -0700 Subject: slab: fix DEBUG_SLAB build Fix CONFIG_SLAB=y CONFIG_DEBUG_SLAB=y build error and warnings. Now that ARCH_SLAB_MINALIGN defaults to __alignof__(unsigned long long), it is always defined (when slab.h included), but cannot be used in #if: mm/slab.c: In function `cache_alloc_debugcheck_after': mm/slab.c:3156:5: warning: "__alignof__" is not defined mm/slab.c:3156:5: error: missing binary operator before token "(" make[1]: *** [mm/slab.o] Error 1 So just remove the #if and #endif lines, but then 64-bit build warns: mm/slab.c: In function `cache_alloc_debugcheck_after': mm/slab.c:3156:6: warning: cast from pointer to integer of different size mm/slab.c:3158:10: warning: format `%d' expects type `int', but argument 3 has type `long unsigned int' Fix those with casts, whatever the actual type of ARCH_SLAB_MINALIGN. Acked-by: Christoph Lameter Signed-off-by: Hugh Dickins Signed-off-by: Pekka Enberg --- mm/slab.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'mm/slab.c') diff --git a/mm/slab.c b/mm/slab.c index bcfa4987c8ae..ef8ceb726e71 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -3153,12 +3153,10 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, objp += obj_offset(cachep); if (cachep->ctor && cachep->flags & SLAB_POISON) cachep->ctor(objp); -#if ARCH_SLAB_MINALIGN - if ((u32)objp & (ARCH_SLAB_MINALIGN-1)) { + if ((unsigned long)objp & (ARCH_SLAB_MINALIGN-1)) { printk(KERN_ERR "0x%p: not aligned to ARCH_SLAB_MINALIGN=%d\n", - objp, ARCH_SLAB_MINALIGN); + objp, (int)ARCH_SLAB_MINALIGN); } -#endif return objp; } #else -- cgit v1.2.3-58-ga151 From b56efcf0a45aa7fc32de90d5f9838541082fbc19 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 20 Jul 2011 19:04:23 +0200 Subject: slab: shrink sizeof(struct kmem_cache) Reduce high order allocations for some setups. (NR_CPUS=4096 -> we need 64KB per kmem_cache struct) We now allocate exact needed size (using nr_cpu_ids and nr_node_ids) This also makes code a bit smaller on x86_64, since some field offsets are less than the 127 limit : Before patch : # size mm/slab.o text data bss dec hex filename 22605 361665 32 384302 5dd2e mm/slab.o After patch : # size mm/slab.o text data bss dec hex filename 22349 353473 8224 384046 5dc2e mm/slab.o CC: Andrew Morton Reported-by: Konstantin Khlebnikov Signed-off-by: Eric Dumazet Acked-by: Christoph Lameter Signed-off-by: Pekka Enberg --- include/linux/slab_def.h | 26 +++++++++++++------------- mm/slab.c | 10 ++++++---- 2 files changed, 19 insertions(+), 17 deletions(-) (limited to 'mm/slab.c') diff --git a/include/linux/slab_def.h b/include/linux/slab_def.h index d7f63112f63c..d00e0bacda93 100644 --- a/include/linux/slab_def.h +++ b/include/linux/slab_def.h @@ -24,21 +24,19 @@ */ struct kmem_cache { -/* 1) per-cpu data, touched during every alloc/free */ - struct array_cache *array[NR_CPUS]; -/* 2) Cache tunables. Protected by cache_chain_mutex */ +/* 1) Cache tunables. Protected by cache_chain_mutex */ unsigned int batchcount; unsigned int limit; unsigned int shared; unsigned int buffer_size; u32 reciprocal_buffer_size; -/* 3) touched by every alloc & free from the backend */ +/* 2) touched by every alloc & free from the backend */ unsigned int flags; /* constant flags */ unsigned int num; /* # of objs per slab */ -/* 4) cache_grow/shrink */ +/* 3) cache_grow/shrink */ /* order of pgs per slab (2^n) */ unsigned int gfporder; @@ -54,11 +52,11 @@ struct kmem_cache { /* constructor func */ void (*ctor)(void *obj); -/* 5) cache creation/removal */ +/* 4) cache creation/removal */ const char *name; struct list_head next; -/* 6) statistics */ +/* 5) statistics */ #ifdef CONFIG_DEBUG_SLAB unsigned long num_active; unsigned long num_allocations; @@ -85,16 +83,18 @@ struct kmem_cache { int obj_size; #endif /* CONFIG_DEBUG_SLAB */ +/* 6) per-cpu/per-node data, touched during every alloc/free */ /* - * We put nodelists[] at the end of kmem_cache, because we want to size - * this array to nr_node_ids slots instead of MAX_NUMNODES + * We put array[] at the end of kmem_cache, because we want to size + * this array to nr_cpu_ids slots instead of NR_CPUS * (see kmem_cache_init()) - * We still use [MAX_NUMNODES] and not [1] or [0] because cache_cache - * is statically defined, so we reserve the max number of nodes. + * We still use [NR_CPUS] and not [1] or [0] because cache_cache + * is statically defined, so we reserve the max number of cpus. */ - struct kmem_list3 *nodelists[MAX_NUMNODES]; + struct kmem_list3 **nodelists; + struct array_cache *array[NR_CPUS]; /* - * Do not add fields after nodelists[] + * Do not add fields after array[] */ }; diff --git a/mm/slab.c b/mm/slab.c index ef8ceb726e71..c3cb3598555a 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -574,7 +574,9 @@ static struct arraycache_init initarray_generic = { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} }; /* internal cache of cache description objs */ +static struct kmem_list3 *cache_cache_nodelists[MAX_NUMNODES]; static struct kmem_cache cache_cache = { + .nodelists = cache_cache_nodelists, .batchcount = 1, .limit = BOOT_CPUCACHE_ENTRIES, .shared = 1, @@ -1492,11 +1494,10 @@ void __init kmem_cache_init(void) cache_cache.nodelists[node] = &initkmem_list3[CACHE_CACHE + node]; /* - * struct kmem_cache size depends on nr_node_ids, which - * can be less than MAX_NUMNODES. + * struct kmem_cache size depends on nr_node_ids & nr_cpu_ids */ - cache_cache.buffer_size = offsetof(struct kmem_cache, nodelists) + - nr_node_ids * sizeof(struct kmem_list3 *); + cache_cache.buffer_size = offsetof(struct kmem_cache, array[nr_cpu_ids]) + + nr_node_ids * sizeof(struct kmem_list3 *); #if DEBUG cache_cache.obj_size = cache_cache.buffer_size; #endif @@ -2308,6 +2309,7 @@ kmem_cache_create (const char *name, size_t size, size_t align, if (!cachep) goto oops; + cachep->nodelists = (struct kmem_list3 **)&cachep->array[nr_cpu_ids]; #if DEBUG cachep->obj_size = size; -- cgit v1.2.3-58-ga151 From 7ea466f2256b02a7047dfd47d76a2f6c1e427e3e Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Thu, 21 Jul 2011 09:42:45 +0900 Subject: slab: fix DEBUG_SLAB warning In commit c225150b "slab: fix DEBUG_SLAB build", "if ((unsigned long)objp & (ARCH_SLAB_MINALIGN-1))" is always true if ARCH_SLAB_MINALIGN == 0. Do not print warning if ARCH_SLAB_MINALIGN == 0. Signed-off-by: Tetsuo Handa Signed-off-by: Pekka Enberg --- mm/slab.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'mm/slab.c') diff --git a/mm/slab.c b/mm/slab.c index c3cb3598555a..dc2f068c0b7d 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -3155,7 +3155,8 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, objp += obj_offset(cachep); if (cachep->ctor && cachep->flags & SLAB_POISON) cachep->ctor(objp); - if ((unsigned long)objp & (ARCH_SLAB_MINALIGN-1)) { + if (ARCH_SLAB_MINALIGN && + ((unsigned long)objp & (ARCH_SLAB_MINALIGN-1))) { printk(KERN_ERR "0x%p: not aligned to ARCH_SLAB_MINALIGN=%d\n", objp, (int)ARCH_SLAB_MINALIGN); } -- cgit v1.2.3-58-ga151