From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with SMTP id B277A6B0082 for ; Mon, 27 Apr 2009 03:01:30 -0400 (EDT) Received: from m5.gw.fujitsu.co.jp ([10.0.50.75]) by fgwmail6.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id n3R71TNM016923 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Mon, 27 Apr 2009 16:01:29 +0900 Received: from smail (m5 [127.0.0.1]) by outgoing.m5.gw.fujitsu.co.jp (Postfix) with ESMTP id 4269B45DE57 for ; Mon, 27 Apr 2009 16:01:29 +0900 (JST) Received: from s5.gw.fujitsu.co.jp (s5.gw.fujitsu.co.jp [10.0.50.95]) by m5.gw.fujitsu.co.jp (Postfix) with ESMTP id 22A0145DE52 for ; Mon, 27 Apr 2009 16:01:29 +0900 (JST) Received: from s5.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s5.gw.fujitsu.co.jp (Postfix) with ESMTP id 0E45E1DB8038 for ; Mon, 27 Apr 2009 16:01:29 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.249.87.104]) by s5.gw.fujitsu.co.jp (Postfix) with ESMTP id B3ECD1DB8043 for ; Mon, 27 Apr 2009 16:01:25 +0900 (JST) Date: Mon, 27 Apr 2009 15:59:53 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [BUGFIX][PATCH] memcg: fix try_get_mem_cgroup_from_swapcache() Message-Id: <20090427155953.32990d5a.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20090427065358.GB4454@balbir.in.ibm.com> References: <20090426231752.36498c90.d-nishimura@mtf.biglobe.ne.jp> <20090427095100.29173bc1.nishimura@mxp.nes.nec.co.jp> <20090427065358.GB4454@balbir.in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: balbir@linux.vnet.ibm.com Cc: Daisuke Nishimura , Andrew Morton , linux-mm List-ID: On Mon, 27 Apr 2009 12:23:58 +0530 Balbir Singh wrote: > * nishimura@mxp.nes.nec.co.jp [2009-04-27 09:51:00]: > > > From: Daisuke Nishimura > > > > memcg: fix try_get_mem_cgroup_from_swapcache() > > > > This is a bugfix for commit 3c776e64660028236313f0e54f3a9945764422df(included 2.6.30-rc1). > > Used bit of swapcache is solid under page lock, but considering move_account, > > pc->mem_cgroup is not. > > > > We need lock_page_cgroup() anyway. > > > > Signed-off-by: Daisuke Nishimura > > I think we need to start documenting the locks the > page_cgroup lock nests under. > Addin some comments on source code may be necessary. > If memcg_tasklist were a spinlock instead of mutex, could we use that > instead of page_cgroup lock, since we care only about task migration? > Hmm ? Another problem ? I can't catch what you ask. move_account() is a function called by force_empty()->"move account to parent" Thanks, -Kame -- 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