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 17:46:30 +0200 Message-ID: <4C4DADD6.90507@kernel.org> References: <4C02C961.9050606@kernel.org> <20100531152221.GB2987@redhat.com> <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> 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: <4C4DAB14.5050809@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 07/26/2010 05:34 PM, Tejun Heo wrote: > Hello, > > On 07/26/2010 05:25 PM, Michael S. Tsirkin wrote: >> BTW, kthread_worker would benefit from the optimization I implemented >> here as well. > > Hmmm... I'm not quite sure whether it's an optimization. I thought > the patch was due to feeling uncomfortable about using barriers? Is > it an optimization? Yeah, one less smp_mb() in execution path. The lock dancing in flush() is ugly but then again mucking with barriers could be harder to understand. Care to send a patch against wq#for-next tree? Thanks. -- tejun