oom: cleanup has_intersects_mems_allowed()

presently has_intersects_mems_allowed() has own thread iterate logic, but
it should use while_each_thread().

It slightly improve the code readability.
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: NMinchan Kim <minchan.kim@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/oom_kill.c

@@ -69,8 +69,8 @@ static bool has_intersects_mems_allowed(struct task_struct *tsk,
 			if (cpuset_mems_allowed_intersects(current, tsk))
 				return true;
 		}
-		tsk = next_thread(tsk);
-	} while (tsk != start);
+	} while_each_thread(start, tsk);
+
 	return false;
 }
 #else