From 7d170856020c6ad96ef4b9dbc24635052587f01f Mon Sep 17 00:00:00 2001
From: Sha Zhengju <handai.szj@taobao.com>
Date: Fri, 13 Apr 2012 08:52:09 +1000
Subject: [PATCH] memcg: revise the position of threshold index while
 unregistering event

Index current_threshold should point to threshold just below or equal to
usage.  See below: http://www.spinics.net/lists/cgroups/msg00844.html

Signed-off-by: Sha Zhengju <handai.szj@taobao.com>
Reviewed-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 mm/memcontrol.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index d564f1d2567c..7ef75a573b7d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -4470,7 +4470,7 @@ static void mem_cgroup_usage_unregister_event(struct cgroup *cgrp,
 			continue;
 
 		new->entries[j] = thresholds->primary->entries[i];
-		if (new->entries[j].threshold < usage) {
+		if (new->entries[j].threshold <= usage) {
 			/*
 			 * new->current_threshold will not be used
 			 * until rcu_assign_pointer(), so it's safe to increment
-- 
2.39.5