From 230e9fc2860450fbb1f33bdcf9093d92d7d91f5b Mon Sep 17 00:00:00 2001 From: Vladimir Davydov Date: Thu, 14 Jan 2016 15:18:15 -0800 Subject: 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 --- mm/memcontrol.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'mm/memcontrol.c') 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; -- cgit v1.2.3-58-ga151