From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752986AbZHaRkg (ORCPT ); Mon, 31 Aug 2009 13:40:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751386AbZHaRkf (ORCPT ); Mon, 31 Aug 2009 13:40:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41778 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750929AbZHaRke (ORCPT ); Mon, 31 Aug 2009 13:40:34 -0400 Message-ID: <4A9C0AEB.6000506@redhat.com> Date: Mon, 31 Aug 2009 13:39:55 -0400 From: Rik van Riel User-Agent: Thunderbird 2.0.0.21 (X11/20090320) MIME-Version: 1.0 To: Vivek Goyal CC: linux-kernel@vger.kernel.org, jens.axboe@oracle.com, containers@lists.linux-foundation.org, dm-devel@redhat.com, nauman@google.com, dpshah@google.com, lizf@cn.fujitsu.com, mikew@google.com, fchecconi@gmail.com, paolo.valente@unimore.it, ryov@valinux.co.jp, fernando@oss.ntt.co.jp, s-uchida@ap.jp.nec.com, taka@valinux.co.jp, guijianfeng@cn.fujitsu.com, jmoyer@redhat.com, dhaval@linux.vnet.ibm.com, balbir@linux.vnet.ibm.com, righi.andrea@gmail.com, m-ikeda@ds.jp.nec.com, agk@redhat.com, akpm@linux-foundation.org, peterz@infradead.org, jmarchan@redhat.com, torvalds@linux-foundation.org, mingo@elte.hu Subject: Re: [PATCH 19/23] io-controller: map async requests to appropriate cgroup References: <1251495072-7780-1-git-send-email-vgoyal@redhat.com> <1251495072-7780-20-git-send-email-vgoyal@redhat.com> In-Reply-To: <1251495072-7780-20-git-send-email-vgoyal@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Vivek Goyal wrote: > o So far we were assuming that a bio/rq belongs to the task who is submitting > it. It did not hold good in case of async writes. This patch makes use of > blkio_cgroup pataches to attribute the aysnc writes to right group instead > of task submitting the bio. > > o For sync requests, we continue to assume that io belongs to the task > submitting it. Only in case of async requests, we make use of io tracking > patches to track the owner cgroup. > > o So far cfq always caches the async queue pointer. With async requests now > not necessarily being tied to submitting task io context, caching the > pointer will not help for async queues. This patch introduces a new config > option CONFIG_TRACK_ASYNC_CONTEXT. If this option is not set, cfq retains > old behavior where async queue pointer is cached in task context. If it > is set, async queue pointer is not cached and we take help of bio > tracking patches to determine group bio belongs to and then map it to > async queue of that group. > > Signed-off-by: Nauman Rafique > Signed-off-by: Gui Jianfeng > Signed-off-by: Vivek Goyal Acked-by: Rik van Riel