diff options
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index ed6338c4467f..85396bae092b 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3230,9 +3230,6 @@ void memcg_register_cache(struct kmem_cache *s) css_get(&memcg->css); - mutex_lock(&memcg->slab_caches_mutex); - list_add(&s->memcg_params->list, &memcg->memcg_slab_caches); - mutex_unlock(&memcg->slab_caches_mutex); /* * Since readers won't lock (see cache_from_memcg_idx()), we need a @@ -3241,7 +3238,16 @@ void memcg_register_cache(struct kmem_cache *s) */ smp_wmb(); + /* + * Initialize the pointer to this cache in its parent's memcg_params + * before adding it to the memcg_slab_caches list, otherwise we can + * fail to convert memcg_params_to_cache() while traversing the list. + */ root->memcg_params->memcg_caches[id] = s; + + mutex_lock(&memcg->slab_caches_mutex); + list_add(&s->memcg_params->list, &memcg->memcg_slab_caches); + mutex_unlock(&memcg->slab_caches_mutex); } void memcg_unregister_cache(struct kmem_cache *s) @@ -3253,16 +3259,21 @@ void memcg_unregister_cache(struct kmem_cache *s) if (is_root_cache(s)) return; - memcg = s->memcg_params->memcg; - id = memcg_cache_id(memcg); - root = s->memcg_params->root_cache; - root->memcg_params->memcg_caches[id] = NULL; + memcg = s->memcg_params->memcg; + id = memcg_cache_id(memcg); mutex_lock(&memcg->slab_caches_mutex); list_del(&s->memcg_params->list); mutex_unlock(&memcg->slab_caches_mutex); + /* + * Clear the pointer to this cache in its parent's memcg_params only + * after removing it from the memcg_slab_caches list, otherwise we can + * fail to convert memcg_params_to_cache() while traversing the list. + */ + root->memcg_params->memcg_caches[id] = NULL; + css_put(&memcg->css); } |