From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751692AbaLZKRO (ORCPT ); Fri, 26 Dec 2014 05:17:14 -0500 Received: from mx1.redhat.com ([209.132.183.28]:59492 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751392AbaLZKRN (ORCPT ); Fri, 26 Dec 2014 05:17:13 -0500 Message-ID: <549D359E.7080401@redhat.com> Date: Fri, 26 Dec 2014 18:17:02 +0800 From: Jason Wang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: rusty@rustcorp.com.au, mst@redhat.com, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 3/3] virtio-net: using single MSIX irq for each TX/RX queue pair References: <1419562425-20614-1-git-send-email-jasowang@redhat.com> <1419562425-20614-4-git-send-email-jasowang@redhat.com> In-Reply-To: <1419562425-20614-4-git-send-email-jasowang@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/26/2014 10:53 AM, Jason Wang wrote: > This patch try to reduce the number of MSIX irqs required for > virtio-net by sharing a MSIX irq for each TX/RX queue pair through > channels. If transport support channel, about half of the MSIX irqs > were reduced. > > Cc: Rusty Russell > Cc: Michael S. Tsirkin > Signed-off-by: Jason Wang > --- > drivers/net/virtio_net.c | 26 +++++++++++++++++++++++++- > 1 file changed, 25 insertions(+), 1 deletion(-) > Note: an issue with this patch is it may trigger tx irq handler if at least one more used. We could solve this by checking the used idx and bypass the tx irq if host does not signal us. (Or just does the old tx skbs reclaiming before the checking.)