From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o888RjH9022531 for ; Wed, 8 Sep 2010 03:27:46 -0500 Received: from mail.internode.on.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 2DEB753BE7 for ; Wed, 8 Sep 2010 01:28:29 -0700 (PDT) Received: from mail.internode.on.net (bld-mail12.adl6.internode.on.net [150.101.137.97]) by cuda.sgi.com with ESMTP id qqgzVNmQuu5Lm8xw for ; Wed, 08 Sep 2010 01:28:29 -0700 (PDT) Date: Wed, 8 Sep 2010 18:28:19 +1000 From: Dave Chinner Subject: Re: [2.6.36-rc3] Workqueues, XFS, dependencies and deadlocks Message-ID: <20100908082819.GV705@dastard> References: <20100907072954.GM705@dastard> <4C86003B.6090706@kernel.org> <20100907100108.GN705@dastard> <4C861582.6080102@kernel.org> <20100907124850.GP705@dastard> <4C865CC4.9070701@kernel.org> <20100908073428.GR705@dastard> <4C87474B.3050405@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <4C87474B.3050405@kernel.org> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Tejun Heo Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, xfs@oss.sgi.com On Wed, Sep 08, 2010 at 10:20:27AM +0200, Tejun Heo wrote: > On 09/08/2010 09:34 AM, Dave Chinner wrote: > >> Probably I have overloaded the term 'concurrency' too much. In this > >> case, I meant the number of workers assigned to work items of the wq. > >> If you fire off N work items which sleep at the same time, cmwq will > >> eventually try to create N workers as each previous worker goes to > >> sleep so that the CPU doesn't sit idle while there are work items to > >> process as long as N < @wq->nr->active. > > > > Ok, so if I queue N items on a single CPU when max_active == N, they > > get spread across N worker threads on different CPUs? > > They may if necessary to keep the workqueue progressing. Ok, so the normal case is that they will all be processed local to the CPU they were queued on, like the old workqueue code? Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs