From nobody Thu Nov 13 12:02:47 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1579860279; cv=none; d=zohomail.com; s=zohoarc; b=k+w8g6YU2cM15t8Y4+lz8VASqGo6Os7WQnfb2vXALmx/pw/T4BGR7og3UX1GVd3BQfP9aBmjLpAyNAlKL42wBg+7QHDCRvzJjb9jEtt0sxy+D/K0l2mP1oGPQ1IyYMEOQaZ0D3Doj5MuM/r165n3msFPvX97bx0I1DsV5Qd1FAg= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1579860279; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=jvQ5GA+mBgNZIB4n151iIGtmYdm0/MUwPyFgTl16W54=; b=ZILtdKln1FSJFsK9SFMz5ok8Fn0RWq7pp4MbtYqy1FGWF/D57ipaoOxywLII4syVYRPPwBTZTTFjOCjN0fM5Ob+CIgaFSRWWAOt3KdUsRJ5bpQeeKZsqZxGjlvK9o3hxEiKu8HhvO/YVksvXZmH45LJbYGOZ+3FNow9JXJTqIg4= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1579860279491578.8102071411885; Fri, 24 Jan 2020 02:04:39 -0800 (PST) Received: from localhost ([::1]:39706 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iuvpO-0001xf-DM for importer@patchew.org; Fri, 24 Jan 2020 05:04:38 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:38206) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iuvnE-0006Lb-GA for qemu-devel@nongnu.org; Fri, 24 Jan 2020 05:02:27 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iuvnD-0006Yr-65 for qemu-devel@nongnu.org; Fri, 24 Jan 2020 05:02:24 -0500 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:26488 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iuvnC-0006YI-P1 for qemu-devel@nongnu.org; Fri, 24 Jan 2020 05:02:22 -0500 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-396-Qup9UDWPNqCqCKtvIJ_NxA-1; Fri, 24 Jan 2020 05:02:18 -0500 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 mimecast-mx01.redhat.com (Postfix) with ESMTPS id 971DB1005510; Fri, 24 Jan 2020 10:02:17 +0000 (UTC) Received: from localhost (ovpn-117-162.ams2.redhat.com [10.36.117.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7322985784; Fri, 24 Jan 2020 10:02:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1579860142; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jvQ5GA+mBgNZIB4n151iIGtmYdm0/MUwPyFgTl16W54=; b=Nc9FEWhwBW0LEdywtgf85re5InHw8nSTUJ+SS4nlGUxr/bK8kmqaJMOEC+MmmUpD+ZVjXD sUc70XX0GWwckYNgiqRd0Ps+uZ9ShuDNNwjfJFcQ+TcwWcP6K9kigXmTBaE9Qy6FXH+xj1 +DTQ+DscU5TCgdv6iXj1Y0XdktmXrE0= From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [PATCH v2 3/4] virtio-blk: default num_queues to -smp N Date: Fri, 24 Jan 2020 10:01:58 +0000 Message-Id: <20200124100159.736209-4-stefanha@redhat.com> In-Reply-To: <20200124100159.736209-1-stefanha@redhat.com> References: <20200124100159.736209-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: Qup9UDWPNqCqCKtvIJ_NxA-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Fam Zheng , Eduardo Habkost , qemu-block@nongnu.org, "Michael S. Tsirkin" , cohuck@redhat.com, Stefan Hajnoczi , Paolo Bonzini , Max Reitz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" Automatically size the number of request virtqueues to match the number of vCPUs. This ensures that completion interrupts are handled on the same vCPU that submitted the request. No IPI is necessary to complete an I/O request and performance is improved. Signed-off-by: Stefan Hajnoczi Reviewed-by: Cornelia Huck --- hw/block/virtio-blk.c | 6 +++++- hw/core/machine.c | 1 + hw/virtio/virtio-blk-pci.c | 9 ++++++++- include/hw/virtio/virtio-blk.h | 2 ++ 4 files changed, 16 insertions(+), 2 deletions(-) diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 9bee514c4e..d3ffaffc93 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -1135,6 +1135,9 @@ static void virtio_blk_device_realize(DeviceState *de= v, Error **errp) error_setg(errp, "Device needs media, but drive is empty"); return; } + if (conf->num_queues =3D=3D VIRTIO_BLK_AUTO_NUM_QUEUES) { + conf->num_queues =3D 1; + } if (!conf->num_queues) { error_setg(errp, "num-queues property must be larger than 0"); return; @@ -1271,7 +1274,8 @@ static Property virtio_blk_properties[] =3D { #endif DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, = 0, true), - DEFINE_PROP_UINT16("num-queues", VirtIOBlock, conf.num_queues, 1), + DEFINE_PROP_UINT16("num-queues", VirtIOBlock, conf.num_queues, + VIRTIO_BLK_AUTO_NUM_QUEUES), DEFINE_PROP_UINT16("queue-size", VirtIOBlock, conf.queue_size, 128), DEFINE_PROP_BOOL("seg-max-adjust", VirtIOBlock, conf.seg_max_adjust, t= rue), DEFINE_PROP_LINK("iothread", VirtIOBlock, conf.iothread, TYPE_IOTHREAD, diff --git a/hw/core/machine.c b/hw/core/machine.c index d6e2370c77..de6ceaa97f 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -28,6 +28,7 @@ #include "hw/mem/nvdimm.h" =20 GlobalProperty hw_compat_4_2[] =3D { + { "virtio-blk-device", "num-queues", "1"}, { "virtio-blk-device", "x-enable-wce-if-config-wce", "off" }, { "virtio-blk-device", "seg-max-adjust", "off"}, { "virtio-scsi-device", "num_queues", "1"}, diff --git a/hw/virtio/virtio-blk-pci.c b/hw/virtio/virtio-blk-pci.c index d9b69a5af3..7e6d863963 100644 --- a/hw/virtio/virtio-blk-pci.c +++ b/hw/virtio/virtio-blk-pci.c @@ -17,6 +17,7 @@ =20 #include "qemu/osdep.h" =20 +#include "hw/boards.h" #include "hw/qdev-properties.h" #include "hw/virtio/virtio-blk.h" #include "virtio-pci.h" @@ -50,9 +51,15 @@ static void virtio_blk_pci_realize(VirtIOPCIProxy *vpci_= dev, Error **errp) { VirtIOBlkPCI *dev =3D VIRTIO_BLK_PCI(vpci_dev); DeviceState *vdev =3D DEVICE(&dev->vdev); + VirtIOBlkConf *conf =3D &dev->vdev.conf; + + /* 1:1 vq to vcpu mapping is ideal because it avoids IPIs */ + if (conf->num_queues =3D=3D VIRTIO_BLK_AUTO_NUM_QUEUES) { + conf->num_queues =3D current_machine->smp.cpus; + } =20 if (vpci_dev->nvectors =3D=3D DEV_NVECTORS_UNSPECIFIED) { - vpci_dev->nvectors =3D dev->vdev.conf.num_queues + 1; + vpci_dev->nvectors =3D conf->num_queues + 1; } =20 qdev_set_parent_bus(vdev, BUS(&vpci_dev->bus)); diff --git a/include/hw/virtio/virtio-blk.h b/include/hw/virtio/virtio-blk.h index 1e62f869b2..4e5e903f4a 100644 --- a/include/hw/virtio/virtio-blk.h +++ b/include/hw/virtio/virtio-blk.h @@ -30,6 +30,8 @@ struct virtio_blk_inhdr unsigned char status; }; =20 +#define VIRTIO_BLK_AUTO_NUM_QUEUES UINT16_MAX + struct VirtIOBlkConf { BlockConf conf; --=20 2.24.1