memcg, slab: kmem_cache_create_memcg(): fix memleak on fail path

We do not free the cache's memcg_params if __kmem_cache_create fails.
Fix this.

Plus, rename memcg_register_cache() to memcg_alloc_cache_params(),
because it actually does not register the cache anywhere, but simply
initialize kmem_cache::memcg_params.

[akpm@linux-foundation.org: fix build]
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>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 3 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 72f2d90e7ef6..b8ebe71f872d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3231,8 +3231,8 @@ int memcg_update_cache_size(struct kmem_cache *s, int num_groups)
         return 0;
 }
 
-int memcg_register_cache(struct mem_cgroup *memcg, struct kmem_cache *s,
-                         struct kmem_cache *root_cache)
+int memcg_alloc_cache_params(struct mem_cgroup *memcg, struct kmem_cache *s,
+                             struct kmem_cache *root_cache)
 {
         size_t size;
 
@@ -3260,6 +3260,11 @@ int memcg_register_cache(struct mem_cgroup *memcg, struct kmem_cache *s,
         return 0;
 }
 
+void memcg_free_cache_params(struct kmem_cache *s)
+{
+        kfree(s->memcg_params);
+}
+
 void memcg_release_cache(struct kmem_cache *s)
 {
         struct kmem_cache *root;
@@ -3288,7 +3293,7 @@ void memcg_release_cache(struct kmem_cache *s)
 
         css_put(&memcg->css);
 out:
-        kfree(s->memcg_params);
+        memcg_free_cache_params(s);
 }
 
 /*