From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH UPDATED 1/3] vhost: replace vhost_workqueue with per-vhost kthread Date: Mon, 26 Jul 2010 18:05:27 +0200 Message-ID: <4C4DB247.9060709@kernel.org> References: <4C03D983.9010905@kernel.org> <20100531160020.GC3067@redhat.com> <4C04D41B.4050704@kernel.org> <4C06A580.9060300@kernel.org> <20100722155840.GA1743@redhat.com> <4C48B664.9000109@kernel.org> <20100724191447.GA4972@redhat.com> <4C4BEAA2.6040301@kernel.org> <20100726152510.GA26223@redhat.com> <4C4DAB14.5050809@kernel.org> <20100726155014.GA26412@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Oleg Nesterov , Sridhar Samudrala , netdev , lkml , "kvm@vger.kernel.org" , Andrew Morton , Dmitri Vorobiev , Jiri Kosina , Thomas Gleixner , Ingo Molnar , Andi Kleen To: "Michael S. Tsirkin" Return-path: In-Reply-To: <20100726155014.GA26412@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Hello, On 07/26/2010 05:50 PM, Michael S. Tsirkin wrote: >> Hmmm... I'm not quite sure whether it's an optimization. I thought >> the patch was due to feeling uncomfortable about using barriers? > > Oh yes. But getting rid of barriers is what motivated me originally. Yeah, getting rid of barriers is always good. :-) > Is there a git tree with kthread_worker applied? > I might do this just for fun ... git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git for-next For the original implementaiton, please take a look at commit b56c0d8937e665a27d90517ee7a746d0aa05af46. * Can you please keep the outer goto repeat loop? I just don't like outermost for (;;). * Placing try_to_freeze() could be a bit annoying. It shouldn't be executed when there's a work to flush. * I think A - B <= 0 test would be more familiar. At least time_before/after() are implemented that way. Thanks. -- tejun