From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: [PATCH 2/3] virtio-pci: Use ioeventfd for virtqueue notify Date: Thu, 11 Nov 2010 19:55:08 +0200 Message-ID: <20101111175508.GG6798@redhat.com> References: <1289483242-6069-1-git-send-email-stefanha@linux.vnet.ibm.com> <1289483242-6069-3-git-send-email-stefanha@linux.vnet.ibm.com> <4CDC20F1.1030305@redhat.com> <20101111171240.GA30171@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Avi Kivity , Stefan Hajnoczi , qemu-devel@nongnu.org, kvm@vger.kernel.org To: "Michael S. Tsirkin" Return-path: Received: from mx1.redhat.com ([209.132.183.28]:1383 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755208Ab0KKRz2 (ORCPT ); Thu, 11 Nov 2010 12:55:28 -0500 Content-Disposition: inline In-Reply-To: <20101111171240.GA30171@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Thu, Nov 11, 2010 at 07:12:40PM +0200, Michael S. Tsirkin wrote: > On Thu, Nov 11, 2010 at 06:59:29PM +0200, Avi Kivity wrote: > > On 11/11/2010 03:47 PM, Stefan Hajnoczi wrote: > > >Some virtio devices are known to have guest drivers which expect a notify to be > > >processed synchronously and spin waiting for completion. Only enable ioeventfd > > >for virtio-blk and virtio-net for now. > > > > Which drivers are these? > > > > I only know of the virtio-gl driver, which isn't upstream. > > I think that PXE virtio drivers do polling. But I think this change does > not break these drivers. It'll probably make them a bit slower. Right, > Gleb? > Can't tell about PXE virtio drivers, but virtio-blk in seabios does polling. -- Gleb.