diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 76c0c99b002fe86d78e380f2b08302c72693e91d..c508258d61a1184aa7c9890bc940c0092ec4f737 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -503,7 +503,6 @@ enum res_type {
  */
 static DEFINE_MUTEX(memcg_create_mutex);
 
-static void mem_cgroup_get(struct mem_cgroup *memcg);
 static void mem_cgroup_put(struct mem_cgroup *memcg);
 
 static inline
@@ -6239,19 +6238,10 @@ static void free_rcu(struct rcu_head *rcu_head)
 	schedule_work(&memcg->work_freeing);
 }
 
-static void mem_cgroup_get(struct mem_cgroup *memcg)
-{
-	atomic_inc(&memcg->refcnt);
-}
-
 static void __mem_cgroup_put(struct mem_cgroup *memcg, int count)
 {
-	if (atomic_sub_and_test(count, &memcg->refcnt)) {
-		struct mem_cgroup *parent = parent_mem_cgroup(memcg);
+	if (atomic_sub_and_test(count, &memcg->refcnt))
 		call_rcu(&memcg->rcu_freeing, free_rcu);
-		if (parent)
-			mem_cgroup_put(parent);
-	}
 }
 
 static void mem_cgroup_put(struct mem_cgroup *memcg)
@@ -6354,12 +6344,9 @@ mem_cgroup_css_online(struct cgroup *cont)
 		res_counter_init(&memcg->kmem, &parent->kmem);
 
 		/*
-		 * We increment refcnt of the parent to ensure that we can
-		 * safely access it on res_counter_charge/uncharge.
-		 * This refcnt will be decremented when freeing this
-		 * mem_cgroup(see mem_cgroup_put).
+		 * No need to take a reference to the parent because cgroup
+		 * core guarantees its existence.
 		 */
-		mem_cgroup_get(parent);
 	} else {
 		res_counter_init(&memcg->res, NULL);
 		res_counter_init(&memcg->memsw, NULL);