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=-3.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 D47E0C433DF for ; Wed, 8 Jul 2020 22:28:04 +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 9A84A20772 for ; Wed, 8 Jul 2020 22:28:04 +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="AGiXd983" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9A84A20772 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]:53166 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jtIXr-000630-Qj for qemu-devel@archiver.kernel.org; Wed, 08 Jul 2020 18:28:03 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:40814) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jtI06-0005KQ-IZ for qemu-devel@nongnu.org; Wed, 08 Jul 2020 17:53:10 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:34629 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 1jtI04-0005KS-RY for qemu-devel@nongnu.org; Wed, 08 Jul 2020 17:53:10 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594245187; 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: in-reply-to:in-reply-to:references:references; bh=zTzr5iD2CS9STbPsb2S2gZXB7VKOk3wVYAvVkMESVIc=; b=AGiXd983W2hD4JGyhQmMZAfE5rGefINfQfObFcFKrbOAcgZ1HojD4PJ74WFF6xdmnSTmFf PoLJXn5WD7EkxjsyIPudvJooFsS3wF1E3f33agTZ6nbGR3+x4O2UvIXhFSHH83BG6C+huB +a10Gp2O79ec4E+Qr1GYMHJgPN0iDpY= 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-330-s8dxpJkBMYiCm1AidWXiFg-1; Wed, 08 Jul 2020 12:50:37 -0400 X-MC-Unique: s8dxpJkBMYiCm1AidWXiFg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1DE101082; Wed, 8 Jul 2020 16:50:35 +0000 (UTC) Received: from gondolin (ovpn-112-239.ams2.redhat.com [10.36.112.239]) by smtp.corp.redhat.com (Postfix) with ESMTP id DB38260E1C; Wed, 8 Jul 2020 16:50:26 +0000 (UTC) Date: Wed, 8 Jul 2020 18:50:12 +0200 From: Cornelia Huck To: Stefan Hajnoczi Subject: Re: [PATCH v5 3/5] virtio-scsi: default num_queues to -smp N Message-ID: <20200708185012.470125bb.cohuck@redhat.com> In-Reply-To: <20200708130526.GD487183@stefanha-x1.localdomain> References: <20200706135650.438362-1-stefanha@redhat.com> <20200706135650.438362-4-stefanha@redhat.com> <20200707174453.50c3ec85.cohuck@redhat.com> <20200708130526.GD487183@stefanha-x1.localdomain> Organization: Red Hat GmbH MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 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: multipart/signed; boundary="Sig_/Dl+_goxTFu6j_rkQ.+Ak8zL"; protocol="application/pgp-signature"; micalg=pgp-sha256 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 17:25:10 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=ham autolearn_force=no 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" --Sig_/Dl+_goxTFu6j_rkQ.+Ak8zL Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Wed, 8 Jul 2020 14:05:26 +0100 Stefan Hajnoczi wrote: > On Tue, Jul 07, 2020 at 05:44:53PM +0200, Cornelia Huck wrote: > > On Mon, 6 Jul 2020 14:56:48 +0100 > > Stefan Hajnoczi wrote: > > > 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(VirtIOPCIProx= y *vpci_dev, Error **errp) > > > { > > > VirtIOSCSIPCI *dev =3D VIRTIO_SCSI_PCI(vpci_dev); > > > DeviceState *vdev =3D DEVICE(&dev->vdev); > > > - VirtIOSCSICommon *vs =3D VIRTIO_SCSI_COMMON(vdev); > > > DeviceState *proxy =3D DEVICE(vpci_dev); > > > + VirtIOSCSIConf *conf =3D &dev->vdev.parent_obj.conf; > > > char *bus_name; > > > =20 > > > + if (conf->num_queues =3D=3D VIRTIO_SCSI_AUTO_NUM_QUEUES) { > > > + conf->num_queues =3D > > > + virtio_pci_optimal_num_queues(VIRTIO_SCSI_VQ_NUM_FIXED); > > > + } > > > + > > > if (vpci_dev->nvectors =3D=3D DEV_NVECTORS_UNSPECIFIED) { > > > - vpci_dev->nvectors =3D vs->conf.num_queues + > > > - VIRTIO_SCSI_VQ_NUM_FIXED + 1; > > > + vpci_dev->nvectors =3D conf->num_queues + VIRTIO_SCSI_VQ_NUM= _FIXED + 1; > > > } > > > =20 > > > /* =20 > >=20 > > 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. =20 >=20 > I agree, I've ignored that case. Other options include printing a > warning or even an error when num_queues disagrees with nvectors. I think an error would be too harsh, but a warning sounds useful. --Sig_/Dl+_goxTFu6j_rkQ.+Ak8zL Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEw9DWbcNiT/aowBjO3s9rk8bwL68FAl8F+UQACgkQ3s9rk8bw L6+V3RAAnYFSyFWK8HM50TTRM8dSI1hjqm7VFu78RJyDX8+cSUku9+/oySGgwlP+ SmERgZKJuh3JqgXMjBMNNB0uRl2kMTMFJr7JmP+RQfNOQgiHPkKjKU7ivAkE9ivv kj1uJbZ3jOjSD2GIVBxGdTl+Kg75B7Zzidhr7uax5H9fSkUQgGuuHng46PqKYPyN 5QpdI+YI3XGr4KGk59yY+CJwlWOcgzd9sh6D2BGjmzQTncVgBSRCS4PGFRki+oMT f/9zzZLDZCBNG7VETThC7aXrezTXsFH13wfz2OUlZ/LVLy5RP6EE7vCLfmoSQHPv 49WzxKY7ee2GlaGh520Cm7fU3AHDDnuTyQA2ac2cDLjDvvYhPbLfOYw0FB4++1lT gW8GISvKeErB5pr8v9c9Ae7MfOC/z2leOywhrKZcwyGfYV9zTiL4XjAU+0WvrNBW Y9dlS5r05dELLQR3ZOtbm/02Tc3gICnYyJofNNUNOpf2r6Blosrrz80WqlrOWHoe UF0ok4lRZ2ZY6abSFuz3AWm/QVOIdT54/rj9DWKeWPJFuNytODDIG7J24NYwcO+7 sBPmzjJgfWkuMV5THvgeCv+kteHJj9ClXfNj5U6zD0ZDb4+tIEk6dv/jjCpaSLS6 GV9obfJ/iokGPkk9G1nouvw+uBt3oi8iBmWDoii5d5t+wDCPHm0= =/oAN -----END PGP SIGNATURE----- --Sig_/Dl+_goxTFu6j_rkQ.+Ak8zL--