Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965815Ab2EOCtO (ORCPT ); Mon, 14 May 2012 22:49:14 -0400 Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:59970 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965170Ab2EOCtK (ORCPT ); Mon, 14 May 2012 22:49:10 -0400 X-SecurityPolicyCheck: OK by SHieldMailChecker v1.7.4 Message-ID: <4FB1C398.1010000@jp.fujitsu.com> Date: Tue, 15 May 2012 11:46:48 +0900 From: KAMEZAWA Hiroyuki User-Agent: Mozilla/5.0 (Windows NT 6.0; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: Glauber Costa CC: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, Tejun Heo , Li Zefan , Greg Thelen , Suleiman Souhlal , Michal Hocko , Johannes Weiner , devel@openvz.org, Christoph Lameter , Pekka Enberg Subject: Re: [PATCH v2 19/29] skip memcg kmem allocations in specified code regions References: <1336758272-24284-1-git-send-email-glommer@parallels.com> <1336758272-24284-20-git-send-email-glommer@parallels.com> In-Reply-To: <1336758272-24284-20-git-send-email-glommer@parallels.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1697 Lines: 48 (2012/05/12 2:44), Glauber Costa wrote: > This patch creates a mechanism that skip memcg allocations during > certain pieces of our core code. It basically works in the same way > as preempt_disable()/preempt_enable(): By marking a region under > which all allocations will be accounted to the root memcg. > > We need this to prevent races in early cache creation, when we > allocate data using caches that are not necessarily created already. > > Signed-off-by: Glauber Costa > CC: Christoph Lameter > CC: Pekka Enberg > CC: Michal Hocko > CC: Kamezawa Hiroyuki > CC: Johannes Weiner > CC: Suleiman Souhlal The concept seems okay to me but... > --- > include/linux/sched.h | 1 + > mm/memcontrol.c | 25 +++++++++++++++++++++++++ > 2 files changed, 26 insertions(+), 0 deletions(-) > > diff --git a/include/linux/sched.h b/include/linux/sched.h > index 81a173c..0501114 100644 > --- a/include/linux/sched.h > +++ b/include/linux/sched.h > @@ -1613,6 +1613,7 @@ struct task_struct { > unsigned long nr_pages; /* uncharged usage */ > unsigned long memsw_nr_pages; /* uncharged mem+swap usage */ > } memcg_batch; > + atomic_t memcg_kmem_skip_account; If only 'current' thread touch this, you don't need to make this atomic counter. you can use 'long'. Thanks, -Kame -- 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/