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=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 41B50C433E0 for ; Tue, 7 Jul 2020 15:46:30 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0C99E20578 for ; Tue, 7 Jul 2020 15:46:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="GsdCnTCi" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0C99E20578 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:58690 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jspnh-0004y2-B9 for qemu-devel@archiver.kernel.org; Tue, 07 Jul 2020 11:46:29 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52956) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jspmU-0003wM-Vp for qemu-devel@nongnu.org; Tue, 07 Jul 2020 11:45:14 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:52781 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jspmT-0002Ix-7c for qemu-devel@nongnu.org; Tue, 07 Jul 2020 11:45:14 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594136712; 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=kEdP4I8aMDYa8nu/w9TG99nR0IbwTAxsF0urigC3Meg=; b=GsdCnTCiFI1qzKmoVLmudAPrS/of7NdgvZ+3gG4sMidYaJrLdpkG2oomeaYCZgHPCHcZmO Vn2xNEcW6CXrDgF1+eYdEvnhy+pbSkNSEPt+KFhGo+UnKQ6fbpxtjJgbpYYZcjFD37GCqm gX8WnXxZKvhmvye5LdUCI819dzkYYKY= 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-85-wyw05sfQNHaQpegA0r27Ew-1; Tue, 07 Jul 2020 11:45:08 -0400 X-MC-Unique: wyw05sfQNHaQpegA0r27Ew-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2A5B31902EA1; Tue, 7 Jul 2020 15:45:07 +0000 (UTC) Received: from gondolin (ovpn-113-54.ams2.redhat.com [10.36.113.54]) by smtp.corp.redhat.com (Postfix) with ESMTP id D2A4F5C1B2; Tue, 7 Jul 2020 15:44:56 +0000 (UTC) Date: Tue, 7 Jul 2020 17:44:53 +0200 From: Cornelia Huck To: Stefan Hajnoczi Subject: Re: [PATCH v5 3/5] virtio-scsi: default num_queues to -smp N Message-ID: <20200707174453.50c3ec85.cohuck@redhat.com> In-Reply-To: <20200706135650.438362-4-stefanha@redhat.com> References: <20200706135650.438362-1-stefanha@redhat.com> <20200706135650.438362-4-stefanha@redhat.com> Organization: Red Hat GmbH MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=cohuck@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=207.211.31.120; envelope-from=cohuck@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/07 00:46:09 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -40 X-Spam_score: -4.1 X-Spam_bar: ---- X-Spam_report: (-4.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action 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" , Pankaj Gupta , qemu-devel@nongnu.org, Raphael Norwitz , Paolo Bonzini , Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, 6 Jul 2020 14:56:48 +0100 Stefan Hajnoczi wrote: Maybe mention 'pci' in the subject as well? > Automatically size the number of virtio-scsi-pci, vhost-scsi-pci, and > vhost-user-scsi-pci request virtqueues to match the number of vCPUs. > Other transports continue to default to 1 request virtqueue. > > A 1:1 virtqueue:vCPU mapping 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. The > maximum number of MSI-X vectors and virtqueues limit are respected. > > Signed-off-by: Stefan Hajnoczi > --- > include/hw/virtio/virtio-scsi.h | 2 ++ > hw/core/machine.c | 3 +++ > hw/scsi/vhost-scsi.c | 3 ++- > hw/scsi/vhost-user-scsi.c | 3 ++- > hw/scsi/virtio-scsi.c | 6 +++++- > hw/virtio/vhost-scsi-pci.c | 10 +++++++--- > hw/virtio/vhost-user-scsi-pci.c | 10 +++++++--- > hw/virtio/virtio-scsi-pci.c | 10 +++++++--- > 8 files changed, 35 insertions(+), 12 deletions(-) (...) > diff --git a/hw/virtio/virtio-scsi-pci.c b/hw/virtio/virtio-scsi-pci.c > index 3ff9eb7ef6..fa4b3bfb50 100644 > --- a/hw/virtio/virtio-scsi-pci.c > +++ b/hw/virtio/virtio-scsi-pci.c > @@ -46,13 +46,17 @@ static void virtio_scsi_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp) > { > VirtIOSCSIPCI *dev = VIRTIO_SCSI_PCI(vpci_dev); > DeviceState *vdev = DEVICE(&dev->vdev); > - VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev); > DeviceState *proxy = DEVICE(vpci_dev); > + VirtIOSCSIConf *conf = &dev->vdev.parent_obj.conf; > char *bus_name; > > + if (conf->num_queues == VIRTIO_SCSI_AUTO_NUM_QUEUES) { > + conf->num_queues = > + virtio_pci_optimal_num_queues(VIRTIO_SCSI_VQ_NUM_FIXED); > + } > + > if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) { > - vpci_dev->nvectors = vs->conf.num_queues + > - VIRTIO_SCSI_VQ_NUM_FIXED + 1; > + vpci_dev->nvectors = conf->num_queues + VIRTIO_SCSI_VQ_NUM_FIXED + 1; > } > > /* One corner case where the setup may end up being a bit odd is a situation where nvectors was specified, but num_queues was not, and the device suddenly ends up with more queues than vectors. But I don't see a reason why you would want to specify nvectors but not num_queues in a real word scenario, so I think we can ignore that corner case. Reviewed-by: Cornelia Huck