From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C2CA1C7618F for ; Fri, 19 Jul 2019 15:14:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A14922173B for ; Fri, 19 Jul 2019 15:14:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728276AbfGSPOd (ORCPT ); Fri, 19 Jul 2019 11:14:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39262 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726711AbfGSPOc (ORCPT ); Fri, 19 Jul 2019 11:14:32 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 42B3FB2DDB; Fri, 19 Jul 2019 15:14:32 +0000 (UTC) Received: from redhat.com (ovpn-124-174.rdu2.redhat.com [10.10.124.174]) by smtp.corp.redhat.com (Postfix) with SMTP id D80FB63F66; Fri, 19 Jul 2019 15:14:29 +0000 (UTC) Date: Fri, 19 Jul 2019 11:14:28 -0400 From: "Michael S. Tsirkin" To: Fei Li Cc: linux-kernel@vger.kernel.org, Jason Wang , Pawel Moll , Suzuki K Poulose , Fam Zheng Subject: Re: [PATCH v1 0/2] virtio-mmio: support multiple interrupt vectors Message-ID: <20190719110852-mutt-send-email-mst@kernel.org> References: <20190719133135.32418-1-lifei.shirley@bytedance.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190719133135.32418-1-lifei.shirley@bytedance.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 19 Jul 2019 15:14:32 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 19, 2019 at 09:31:33PM +0800, Fei Li wrote: > Hi, > > This patch series implements multiple interrupt vectors support for > virtio-mmio device. This is especially useful for multiqueue vhost-net > device when using firecracker micro-vms as the guest. > > Test result: > With 8 vcpus & 8 net queues set, one vhost-net device with 8 irqs can > receive 9 times more pps comparing with only one irq: > - 564830.38 rxpck/s for 8 irqs on > - 67665.06 rxpck/s for 1 irq on > > Please help to review, thanks! > > Have a nice day > Fei Interesting. The spec says though: 4.2.3.4 Notifications From The Device The memory mapped virtio device is using a single, dedicated interrupt signal, which is asserted when at least one of the bits described in the description of InterruptStatus is set. This is how the device sends a used buffer notification or a configuration change notification to the device. So I'm guessing we need to change the host/guest interface? If true pls cc virtio-dev. Also, do we need to update dt bindings documentation? > > Fam Zheng (1): > virtio-mmio: Process vrings more proactively > > Fei Li (1): > virtio-mmio: support multiple interrupt vectors > > drivers/virtio/virtio_mmio.c | 238 +++++++++++++++++++++++++++++++++++-------- > 1 file changed, 196 insertions(+), 42 deletions(-) > > -- > 2.11.0