From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id F22356B0071 for ; Sun, 17 Jan 2010 21:24:55 -0500 (EST) Received: from m2.gw.fujitsu.co.jp ([10.0.50.72]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id o0I2OrWA023195 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Mon, 18 Jan 2010 11:24:53 +0900 Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 6AC8A45DE64 for ; Mon, 18 Jan 2010 11:24:53 +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 3357B45DE5D for ; Mon, 18 Jan 2010 11:24:53 +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 095C61DB8038 for ; Mon, 18 Jan 2010 11:24:53 +0900 (JST) Received: from m105.s.css.fujitsu.com (m105.s.css.fujitsu.com [10.249.87.105]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 5B09E1DB8041 for ; Mon, 18 Jan 2010 11:24:52 +0900 (JST) From: KOSAKI Motohiro Subject: Re: [PATCH 2/3][v2] vmstat: add anon_scan_ratio field to zoneinfo In-Reply-To: <4B53C466.4010103@redhat.com> References: <28c262361001171810w544614b7rdd3df0f984692f35@mail.gmail.com> <4B53C466.4010103@redhat.com> Message-Id: <20100118112359.AE3C.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Date: Mon, 18 Jan 2010 11:24:51 +0900 (JST) Sender: owner-linux-mm@kvack.org To: Rik van Riel Cc: kosaki.motohiro@jp.fujitsu.com, Minchan Kim , LKML , linux-mm , Andrew Morton , Balbir Singh , KAMEZAWA Hiroyuki List-ID: > On 01/17/2010 09:10 PM, Minchan Kim wrote: > > > Absoultely right. I missed that. Thanks. > > get_scan_ratio used lru_lock to get reclaim_stat->recent_xxxx. > > But, it doesn't used lru_lock to get ap/fp. > > > > Is it intentional? I think you or Rik know it. :) > > I think if we want to get exact value, we have to use lru_lock until > > getting ap/fp. > > If it isn't, we don't need lru_lock when we get the reclaim_stat->recent_xxxx. > > > > What do you think about it? > > This is definately not intentional. Really? So, I'll post next patch. Thanks. > Getting race conditions in this code could throw off the > statistics by a factor 2. I do not know how serious that > would be for the VM or whether (and how quickly) it would > self correct. > > -- > All rights reversed. -- 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/ . Don't email: email@kvack.org