diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 051b82ebf371..4efa56a91447 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3423,9 +3423,6 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg)
 		return;
 
 	parent = parent_mem_cgroup(memcg);
-	if (!parent)
-		parent = root_mem_cgroup;
-
 	memcg_reparent_list_lrus(memcg, parent);
 
 	/*
@@ -3705,8 +3702,6 @@ struct mem_cgroup *mem_cgroup_private_id_get_online(struct mem_cgroup *memcg, un
 			break;
 		}
 		memcg = parent_mem_cgroup(memcg);
-		if (!memcg)
-			memcg = root_mem_cgroup;
 	}
 	return memcg;
 }
diff --git a/mm/shrinker.c b/mm/shrinker.c
index c23086bccf4d..76b3f750cf65 100644
--- a/mm/shrinker.c
+++ b/mm/shrinker.c
@@ -288,14 +288,10 @@ void reparent_shrinker_deferred(struct mem_cgroup *memcg)
 {
 	int nid, index, offset;
 	long nr;
-	struct mem_cgroup *parent;
+	struct mem_cgroup *parent = parent_mem_cgroup(memcg);
 	struct shrinker_info *child_info, *parent_info;
 	struct shrinker_info_unit *child_unit, *parent_unit;
 
-	parent = parent_mem_cgroup(memcg);
-	if (!parent)
-		parent = root_mem_cgroup;
-
 	/* Prevent from concurrent shrinker_info expand */
 	mutex_lock(&shrinker_mutex);
 	for_each_node(nid) {