From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx145.postini.com [74.125.245.145]) by kanga.kvack.org (Postfix) with SMTP id 1F98A6B00EC for ; Wed, 28 Mar 2012 07:02:27 -0400 (EDT) Received: from m2.gw.fujitsu.co.jp (unknown [10.0.50.72]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id B73813EE0C0 for ; Wed, 28 Mar 2012 20:02:25 +0900 (JST) Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 9DEAF45DD78 for ; Wed, 28 Mar 2012 20:02:25 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (s2.gw.fujitsu.co.jp [10.0.50.92]) by m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 8678745DE4E for ; Wed, 28 Mar 2012 20:02:25 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 793B81DB803A for ; Wed, 28 Mar 2012 20:02:25 +0900 (JST) Received: from ml13.s.css.fujitsu.com (ml13.s.css.fujitsu.com [10.240.81.133]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 3358F1DB802C for ; Wed, 28 Mar 2012 20:02:25 +0900 (JST) Message-ID: <4F72EF56.4030606@jp.fujitsu.com> Date: Wed, 28 Mar 2012 20:00:38 +0900 From: KAMEZAWA Hiroyuki MIME-Version: 1.0 Subject: [RFC][PATCH 5/6] memcg: remove unnecessary memory barrier. References: <4F72EB84.7080000@jp.fujitsu.com> In-Reply-To: <4F72EB84.7080000@jp.fujitsu.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: "linux-mm@kvack.org" Cc: Linux Kernel , Michal Hocko , Johannes Weiner , Andrew Morton , Han Ying , Glauber Costa , Konstantin Khlebnikov , Suleiman Souhlal Now, Used bit and a pointer to memory cgroup are set at once. memory barrier for Used bit -> pc->mem_cgroup is not necessary. Signed-off-by: KAMEZAWA Hiroyuki --- mm/memcontrol.c | 2 -- 1 files changed, 0 insertions(+), 2 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 622fd2e..767bef3 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1258,8 +1258,6 @@ mem_cgroup_get_reclaim_stat_from_page(struct page *page) pc = lookup_page_cgroup(page); if (!PageCgroupUsed(pc)) return NULL; - /* Ensure pc's mem_cgroup is visible after reading PCG_USED. */ - smp_rmb(); mz = page_cgroup_zoneinfo(pc_to_mem_cgroup(pc), page); return &mz->reclaim_stat; } -- 1.7.4.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org