1 files changed, 8 insertions, 10 deletions

diff --git a/mm/shrinker.c b/mm/shrinker.c
index 76b3f750cf65..7082d01c8c9d 100644
--- a/mm/shrinker.c
+++ b/mm/shrinker.c
@@ -197,12 +197,13 @@ void set_shrinker_bit(struct mem_cgroup *memcg, int nid, int shrinker_id)
 {
 	if (shrinker_id >= 0 && memcg && !mem_cgroup_is_root(memcg)) {
 		struct shrinker_info *info;
-		struct shrinker_info_unit *unit;
 
 		rcu_read_lock();
 		info = rcu_dereference(memcg->nodeinfo[nid]->shrinker_info);
-		unit = info->unit[shrinker_id_to_index(shrinker_id)];
 		if (!WARN_ON_ONCE(shrinker_id >= info->map_nr_max)) {
+			struct shrinker_info_unit *unit;
+
+			unit = info->unit[shrinker_id_to_index(shrinker_id)];
 			/* Pairs with smp mb in shrink_slab() */
 			smp_mb__before_atomic();
 			set_bit(shrinker_id_to_offset(shrinker_id), unit->map);
@@ -215,29 +216,26 @@ static DEFINE_IDR(shrinker_idr);
 
 static int shrinker_memcg_alloc(struct shrinker *shrinker)
 {
-	int id, ret = -ENOMEM;
+	int id;
 
 	if (mem_cgroup_disabled())
 		return -ENOSYS;
 	if (mem_cgroup_kmem_disabled() && !(shrinker->flags & SHRINKER_NONSLAB))
 		return -ENOSYS;
 
-	mutex_lock(&shrinker_mutex);
+	guard(mutex)(&shrinker_mutex);
 	id = idr_alloc(&shrinker_idr, shrinker, 0, 0, GFP_KERNEL);
 	if (id < 0)
-		goto unlock;
+		return id;
 
 	if (id >= shrinker_nr_max) {
 		if (expand_shrinker_info(id)) {
 			idr_remove(&shrinker_idr, id);
-			goto unlock;
+			return -ENOMEM;
 		}
 	}
 	shrinker->id = id;
-	ret = 0;
-unlock:
-	mutex_unlock(&shrinker_mutex);
-	return ret;
+	return 0;
 }
 
 static void shrinker_memcg_remove(struct shrinker *shrinker)