diff options
Diffstat (limited to 'mm/slab_common.c')
| -rw-r--r-- | mm/slab_common.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/mm/slab_common.c b/mm/slab_common.c index db24ec48b94..f34707eeacc 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -180,6 +180,18 @@ kmem_cache_create_memcg(struct mem_cgroup *memcg, const char *name, size_t size, if (err) goto out_unlock; + if (memcg) { + /* + * Since per-memcg caches are created asynchronously on first + * allocation (see memcg_kmem_get_cache()), several threads can + * try to create the same cache, but only one of them may + * succeed. Therefore if we get here and see the cache has + * already been created, we silently return NULL. + */ + if (cache_from_memcg_idx(parent_cache, memcg_cache_id(memcg))) + goto out_unlock; + } + /* * Some allocators will constraint the set of valid flags to a subset * of all flags. We expect them to define CACHE_CREATE_MASK in this @@ -261,11 +273,11 @@ void kmem_cache_destroy(struct kmem_cache *s) list_del(&s->list); if (!__kmem_cache_shutdown(s)) { + memcg_unregister_cache(s); mutex_unlock(&slab_mutex); if (s->flags & SLAB_DESTROY_BY_RCU) rcu_barrier(); - memcg_unregister_cache(s); memcg_free_cache_params(s); kfree(s->name); kmem_cache_free(kmem_cache, s); |