diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 1947218..4748966 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1448,11 +1448,12 @@
 	return ret;
 }
 
-int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *memcg)
+bool task_in_mem_cgroup(struct task_struct *task,
+			const struct mem_cgroup *memcg)
 {
-	int ret;
 	struct mem_cgroup *curr = NULL;
 	struct task_struct *p;
+	bool ret;
 
 	p = find_lock_task_mm(task);
 	if (p) {
@@ -1464,14 +1465,14 @@
 		 * killer still needs to detect if they have already been oom
 		 * killed to prevent needlessly killing additional tasks.
 		 */
-		task_lock(task);
+		rcu_read_lock();
 		curr = mem_cgroup_from_task(task);
 		if (curr)
 			css_get(&curr->css);
-		task_unlock(task);
+		rcu_read_unlock();
 	}
 	if (!curr)
-		return 0;
+		return false;
 	/*
 	 * We should check use_hierarchy of "memcg" not "curr". Because checking
 	 * use_hierarchy of "curr" here make this function true if hierarchy is