memcg: get rid of kmem_cache_dup()

kmem_cache_dup() is only called from memcg_create_kmem_cache().  The
latter, in fact, does nothing besides this, so let's fold
kmem_cache_dup() into memcg_create_kmem_cache().

This patch also makes the memcg_cache_mutex private to
memcg_create_kmem_cache(), because it is not used anywhere else.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Glauber Costa <glommer@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Vladimir Davydov 2014-01-23 15:53:03 -08:00 committed by Linus Torvalds
parent 2edefe1155
commit 842e287369

View File

@ -3427,27 +3427,16 @@ void mem_cgroup_destroy_cache(struct kmem_cache *cachep)
schedule_work(&cachep->memcg_params->destroy);
}
/*
* This lock protects updaters, not readers. We want readers to be as fast as
* they can, and they will either see NULL or a valid cache value. Our model
* allow them to see NULL, in which case the root memcg will be selected.
*
* We need this lock because multiple allocations to the same cache from a non
* will span more than one worker. Only one of them can create the cache.
*/
static DEFINE_MUTEX(memcg_cache_mutex);
/*
* Called with memcg_cache_mutex held
*/
static struct kmem_cache *kmem_cache_dup(struct mem_cgroup *memcg,
struct kmem_cache *s)
static struct kmem_cache *memcg_create_kmem_cache(struct mem_cgroup *memcg,
struct kmem_cache *s)
{
struct kmem_cache *new;
static char *tmp_name = NULL;
static DEFINE_MUTEX(mutex); /* protects tmp_name */
lockdep_assert_held(&memcg_cache_mutex);
BUG_ON(!memcg_can_account_kmem(memcg));
mutex_lock(&mutex);
/*
* kmem_cache_create_memcg duplicates the given name and
* cgroup_name for this name requires RCU context.
@ -3470,25 +3459,13 @@ static struct kmem_cache *kmem_cache_dup(struct mem_cgroup *memcg,
if (new)
new->allocflags |= __GFP_KMEMCG;
else
new = s;
mutex_unlock(&mutex);
return new;
}
static struct kmem_cache *memcg_create_kmem_cache(struct mem_cgroup *memcg,
struct kmem_cache *cachep)
{
struct kmem_cache *new_cachep;
BUG_ON(!memcg_can_account_kmem(memcg));
mutex_lock(&memcg_cache_mutex);
new_cachep = kmem_cache_dup(memcg, cachep);
if (new_cachep == NULL)
new_cachep = cachep;
mutex_unlock(&memcg_cache_mutex);
return new_cachep;
}
void kmem_cache_destroy_memcg_children(struct kmem_cache *s)
{
struct kmem_cache *c;