From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: [PATCH] qemu:virtio: Allow guest to defer VIRTIO_F_NOTIFY_ON_EMPTY Date: Fri, 20 Mar 2009 12:31:29 -0500 Message-ID: <49C3D2F1.2050305@us.ibm.com> References: <20090319162118.24068.98794.stgit@kvm.aw> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org To: Alex Williamson Return-path: Received: from e34.co.us.ibm.com ([32.97.110.152]:36376 "EHLO e34.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752052AbZCTRbu (ORCPT ); Fri, 20 Mar 2009 13:31:50 -0400 Received: from d03relay04.boulder.ibm.com (d03relay04.boulder.ibm.com [9.17.195.106]) by e34.co.us.ibm.com (8.13.1/8.13.1) with ESMTP id n2KHThDe011512 for ; Fri, 20 Mar 2009 11:29:43 -0600 Received: from d03av03.boulder.ibm.com (d03av03.boulder.ibm.com [9.17.195.169]) by d03relay04.boulder.ibm.com (8.13.8/8.13.8/NCO v9.2) with ESMTP id n2KHVWew106660 for ; Fri, 20 Mar 2009 11:31:33 -0600 Received: from d03av03.boulder.ibm.com (loopback [127.0.0.1]) by d03av03.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id n2KHVV0B023682 for ; Fri, 20 Mar 2009 11:31:31 -0600 In-Reply-To: <20090319162118.24068.98794.stgit@kvm.aw> Sender: kvm-owner@vger.kernel.org List-ID: Alex Williamson wrote: > There may be cases where the guest does not want the avail queue > interrupt, even when it's empty. For the virtio-net case, the > guest may use a different buffering scheme or decide polling for > used buffers is more efficient. This can be accomplished by simply > checking for whether the guest has acknowledged the existing notify > on empty flag. > > Signed-off-by: Alex Williamson > Applied to trunk and stable. Thanks. Regards, Anthony Liguori >