From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rik van Riel Subject: Re: [PATCH 19/23] io-controller: map async requests to appropriate cgroup Date: Mon, 31 Aug 2009 13:39:55 -0400 Message-ID: <4A9C0AEB.6000506__26236.7683732466$1251740467$gmane$org@redhat.com> References: <1251495072-7780-1-git-send-email-vgoyal@redhat.com> <1251495072-7780-20-git-send-email-vgoyal@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1251495072-7780-20-git-send-email-vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Vivek Goyal Cc: dhaval-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org, dm-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, jens.axboe-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, agk-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, balbir-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org, paolo.valente-rcYM44yAMweonA0d6jMUrA@public.gmane.org, jmarchan-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, fernando-gVGce1chcLdL9jVzuh4AOg@public.gmane.org, jmoyer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, mingo-X9Un+BFzKDI@public.gmane.org, fchecconi-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, righi.andrea-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org List-Id: containers.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