Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758549AbZIGAvN (ORCPT ); Sun, 6 Sep 2009 20:51:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758420AbZIGAvM (ORCPT ); Sun, 6 Sep 2009 20:51:12 -0400 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:34447 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758459AbZIGAvK (ORCPT ); Sun, 6 Sep 2009 20:51:10 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Date: Mon, 7 Sep 2009 09:49:12 +0900 From: KAMEZAWA Hiroyuki To: nishimura@mxp.nes.nec.co.jp Cc: Daisuke Nishimura , Andrew Morton , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "balbir@linux.vnet.ibm.com" Subject: Re: [mmotm][BUGFIX][PATCH] memcg: fix softlimit css refcnt handling(yet another one) Message-Id: <20090907094912.5cbbbaa5.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20090907080403.5e4510b3.d-nishimura@mtf.biglobe.ne.jp> References: <20090902093438.eed47a57.kamezawa.hiroyu@jp.fujitsu.com> <20090902134114.b6f1a04d.kamezawa.hiroyu@jp.fujitsu.com> <20090902182923.c6d98fd6.kamezawa.hiroyu@jp.fujitsu.com> <20090903141727.ccde7e91.nishimura@mxp.nes.nec.co.jp> <20090904131835.ac2b8cc8.kamezawa.hiroyu@jp.fujitsu.com> <20090904141157.4640ec1e.nishimura@mxp.nes.nec.co.jp> <20090904142143.15ffcb53.kamezawa.hiroyu@jp.fujitsu.com> <20090904142654.08dd159f.kamezawa.hiroyu@jp.fujitsu.com> <20090904154050.25873aa5.nishimura@mxp.nes.nec.co.jp> <20090904163758.a5604fee.kamezawa.hiroyu@jp.fujitsu.com> <20090904190726.6442f3df.d-nishimura@mtf.biglobe.ne.jp> <20090907080403.5e4510b3.d-nishimura@mtf.biglobe.ne.jp> Organization: FUJITSU Co. LTD. X-Mailer: Sylpheed 2.5.0 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2708 Lines: 81 On Mon, 7 Sep 2009 08:04:03 +0900 Daisuke Nishimura wrote: > On Fri, 4 Sep 2009 19:07:26 +0900 > Daisuke Nishimura wrote: > > > On Fri, 4 Sep 2009 16:37:58 +0900 > > KAMEZAWA Hiroyuki wrote: > > > > > On Fri, 4 Sep 2009 15:40:50 +0900 > > > Daisuke Nishimura wrote: > > > > > Ah, one more question. What memory.usage_in_bytes shows in that case ? > > > > > If not zero, charge/uncharge coalescing is guilty. > > > > > > > > > usage_in_bytes is 0. > > > > I've confirmed by crash command that the mem_cgroup has extra ref counts. > > > > > > > > I'll dig more.. > > > > > > > BTW, do you use softlimit ? I found this but...Hmm > > > > > No. > > I'm sorry I can't access my machine, so can't test this. > > > > > > But I think this patch itself is needed and looks good. > > > I've found the cause of the issue. > > Andrew, could you add this one after KAMEZAWA-san's > memory-controller-soft-limit-reclaim-on-contention-v9-fix-softlimit-css-refcnt-handling.patch ? > > === > From: Daisuke Nishimura > > refcount of the "victim" should be decremented before exiting the loop. > > Signed-off-by: Daisuke Nishimura Nice! Acked-by: KAMEZAWA Hiroyuki > --- > mm/memcontrol.c | 8 ++++++-- > 1 files changed, 6 insertions(+), 2 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index ac51294..011aba6 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -1133,8 +1133,10 @@ static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, > * anything, it might because there are > * no reclaimable pages under this hierarchy > */ > - if (!check_soft || !total) > + if (!check_soft || !total) { > + css_put(&victim->css); > break; > + } > /* > * We want to do more targetted reclaim. > * excess >> 2 is not to excessive so as to > @@ -1142,8 +1144,10 @@ static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, > * coming back to reclaim from this cgroup > */ > if (total >= (excess >> 2) || > - (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) > + (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) { > + css_put(&victim->css); > break; > + } > } > } > if (!mem_cgroup_local_usage(&victim->stat)) { > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/