From 230e9fc2860450fbb1f33bdcf9093d92d7d91f5b Mon Sep 17 00:00:00 2001 From: Vladimir Davydov Date: Thu, 14 Jan 2016 15:18:15 -0800 Subject: [PATCH] slab: add SLAB_ACCOUNT flag Currently, if we want to account all objects of a particular kmem cache, we have to pass __GFP_ACCOUNT to each kmem_cache_alloc call, which is inconvenient. This patch introduces SLAB_ACCOUNT flag which if passed to kmem_cache_create will force accounting for every allocation from this cache even if __GFP_ACCOUNT is not passed. This patch does not make any of the existing caches use this flag - it will be done later in the series. Note, a cache with SLAB_ACCOUNT cannot be merged with a cache w/o SLAB_ACCOUNT, because merged caches share the same kmem_cache struct and hence cannot have different sets of SLAB_* flags. Thus using this flag will probably reduce the number of merged slabs even if kmem accounting is not used (only compiled in). Signed-off-by: Vladimir Davydov Suggested-by: Tejun Heo Acked-by: Johannes Weiner Acked-by: Michal Hocko Cc: Greg Thelen Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 15 +++++++-------- include/linux/slab.h | 5 +++++ mm/memcontrol.c | 8 +++++++- mm/slab.h | 5 +++-- mm/slab_common.c | 3 ++- mm/slub.c | 2 ++ 6 files changed, 26 insertions(+), 12 deletions(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index c9d9a8e7b45f..5c97265c1c6e 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -766,15 +766,13 @@ static inline int memcg_cache_id(struct mem_cgroup *memcg) return memcg ? memcg->kmemcg_id : -1; } -struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep); +struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp); void __memcg_kmem_put_cache(struct kmem_cache *cachep); -static inline bool __memcg_kmem_bypass(gfp_t gfp) +static inline bool __memcg_kmem_bypass(void) { if (!memcg_kmem_enabled()) return true; - if (!(gfp & __GFP_ACCOUNT)) - return true; if (in_interrupt() || (!current->mm) || (current->flags & PF_KTHREAD)) return true; return false; @@ -791,7 +789,9 @@ static inline bool __memcg_kmem_bypass(gfp_t gfp) static __always_inline int memcg_kmem_charge(struct page *page, gfp_t gfp, int order) { - if (__memcg_kmem_bypass(gfp)) + if (__memcg_kmem_bypass()) + return 0; + if (!(gfp & __GFP_ACCOUNT)) return 0; return __memcg_kmem_charge(page, gfp, order); } @@ -810,16 +810,15 @@ static __always_inline void memcg_kmem_uncharge(struct page *page, int order) /** * memcg_kmem_get_cache: selects the correct per-memcg cache for allocation * @cachep: the original global kmem cache - * @gfp: allocation flags. * * All memory allocated from a per-memcg cache is charged to the owner memcg. */ static __always_inline struct kmem_cache * memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp) { - if (__memcg_kmem_bypass(gfp)) + if (__memcg_kmem_bypass()) return cachep; - return __memcg_kmem_get_cache(cachep); + return __memcg_kmem_get_cache(cachep, gfp); } static __always_inline void memcg_kmem_put_cache(struct kmem_cache *cachep) diff --git a/include/linux/slab.h b/include/linux/slab.h index 2037a861e367..3ffee7422012 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -86,6 +86,11 @@ #else # define SLAB_FAILSLAB 0x00000000UL #endif +#ifdef CONFIG_MEMCG_KMEM +# define SLAB_ACCOUNT 0x04000000UL /* Account to memcg */ +#else +# define SLAB_ACCOUNT 0x00000000UL +#endif /* The following flags affect the page allocator grouping pages by mobility */ #define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */ diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 14cb1db4c52b..4bd6c4513393 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2356,7 +2356,7 @@ static void memcg_schedule_kmem_cache_create(struct mem_cgroup *memcg, * Can't be called in interrupt context or from kernel threads. * This function needs to be called with rcu_read_lock() held. */ -struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep) +struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp) { struct mem_cgroup *memcg; struct kmem_cache *memcg_cachep; @@ -2364,6 +2364,12 @@ struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep) VM_BUG_ON(!is_root_cache(cachep)); + if (cachep->flags & SLAB_ACCOUNT) + gfp |= __GFP_ACCOUNT; + + if (!(gfp & __GFP_ACCOUNT)) + return cachep; + if (current->memcg_kmem_skip_account) return cachep; diff --git a/mm/slab.h b/mm/slab.h index 7b6087197997..c63b8699cfa3 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -128,10 +128,11 @@ static inline unsigned long kmem_cache_flags(unsigned long object_size, #if defined(CONFIG_SLAB) #define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \ - SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | SLAB_NOTRACK) + SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \ + SLAB_NOTRACK | SLAB_ACCOUNT) #elif defined(CONFIG_SLUB) #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ - SLAB_TEMPORARY | SLAB_NOTRACK) + SLAB_TEMPORARY | SLAB_NOTRACK | SLAB_ACCOUNT) #else #define SLAB_CACHE_FLAGS (0) #endif diff --git a/mm/slab_common.c b/mm/slab_common.c index 3c6a86b4ec25..e016178063e1 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -37,7 +37,8 @@ struct kmem_cache *kmem_cache; SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE | \ SLAB_FAILSLAB) -#define SLAB_MERGE_SAME (SLAB_RECLAIM_ACCOUNT | SLAB_CACHE_DMA | SLAB_NOTRACK) +#define SLAB_MERGE_SAME (SLAB_RECLAIM_ACCOUNT | SLAB_CACHE_DMA | \ + SLAB_NOTRACK | SLAB_ACCOUNT) /* * Merge control. If this is set then no merging of slab caches will occur. diff --git a/mm/slub.c b/mm/slub.c index 46997517406e..2d0e610d195a 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -5362,6 +5362,8 @@ static char *create_unique_id(struct kmem_cache *s) *p++ = 'F'; if (!(s->flags & SLAB_NOTRACK)) *p++ = 't'; + if (s->flags & SLAB_ACCOUNT) + *p++ = 'A'; if (p != name + 1) *p++ = '-'; p += sprintf(p, "%07d", s->size); -- GitLab