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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 2D4BFC433F5 for ; Thu, 3 Mar 2022 12:02:42 +0000 (UTC) Received: from localhost ([::1]:52834 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nPkAK-0005Mg-IB for qemu-devel@archiver.kernel.org; Thu, 03 Mar 2022 07:02:40 -0500 Received: from eggs.gnu.org ([209.51.188.92]:36376) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nPk7t-00027c-K9 for qemu-devel@nongnu.org; Thu, 03 Mar 2022 07:00:09 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:58248) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nPk7p-0003L6-Q7 for qemu-devel@nongnu.org; Thu, 03 Mar 2022 07:00:07 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646308803; 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=pmMcfWY17idQ1ohLoyYQ5VFlBA6g9K5zLlRbNyqkFEE=; b=IGVJJ8MWcdvBxLp0nbAmwYCIfYvmucBmufq55i9gEfrPIYsoHHV5t5ZtpMiCCmcpWrYnge 3nUjgNxF8kqM23NIHeLLanU8ZlNNByHlh3/7PNQwY0NETG5a0Li0me8Did5MR54U/GaNW7 e7tzWe+Qa4YC5sEnLV7+y3mZkH/z2Jw= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-643-27k8PgKZNnGxeOj9X-dK4w-1; Thu, 03 Mar 2022 07:00:00 -0500 X-MC-Unique: 27k8PgKZNnGxeOj9X-dK4w-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 6BC1E18009C5; Thu, 3 Mar 2022 11:59:58 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.36.112.3]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 6251B84951; Thu, 3 Mar 2022 11:59:44 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 8122621E6A00; Thu, 3 Mar 2022 12:59:42 +0100 (CET) From: Markus Armbruster To: Eugenio Perez Martin Subject: Re: [PATCH v3 14/14] vdpa: Add x-svq to NetdevVhostVDPAOptions References: <20220302203012.3476835-1-eperezma@redhat.com> <20220302203012.3476835-15-eperezma@redhat.com> <87ee3jeff1.fsf@pond.sub.org> Date: Thu, 03 Mar 2022 12:59:42 +0100 In-Reply-To: (Eugenio Perez Martin's message of "Thu, 3 Mar 2022 10:53:22 +0100") Message-ID: <87bkyncklt.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) 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=armbru@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=170.10.129.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Michael S. Tsirkin" , Jason Wang , qemu-level , Peter Xu , virtualization , Eli Cohen , Eric Blake , Parav Pandit , Cindy Lu , "Fangyi \(Eric\)" , yebiaoxiang@huawei.com, Liuxiangdong , Stefano Garzarella , Laurent Vivier , Eduardo Habkost , Richard Henderson , Gautam Dawar , Xiao W Wang , Stefan Hajnoczi , Juan Quintela , Harpreet Singh Anand , Zhu Lingshan Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Eugenio Perez Martin writes: > On Thu, Mar 3, 2022 at 7:09 AM Markus Armbruster wrot= e: >> >> Eugenio P=C3=A9rez writes: >> >> > Finally offering the possibility to enable SVQ from the command line. >> > >> > Signed-off-by: Eugenio P=C3=A9rez >> > --- >> > qapi/net.json | 5 ++++- >> > net/vhost-vdpa.c | 48 ++++++++++++++++++++++++++++++++++++++++-------= - >> > 2 files changed, 44 insertions(+), 9 deletions(-) >> > >> > diff --git a/qapi/net.json b/qapi/net.json >> > index 7fab2e7cd8..d243701527 100644 >> > --- a/qapi/net.json >> > +++ b/qapi/net.json >> > @@ -445,12 +445,15 @@ >> > # @queues: number of queues to be created for multiqueue vhost-vdpa >> > # (default: 1) >> > # >> > +# @x-svq: Start device with (experimental) shadow virtqueue. (Since 7= .0) >> > +# >> > # Since: 5.1 >> > ## >> > { 'struct': 'NetdevVhostVDPAOptions', >> > 'data': { >> > '*vhostdev': 'str', >> > - '*queues': 'int' } } >> > + '*queues': 'int', >> > + '*x-svqs': 'bool' } } >> >> Experimental members *must* be tagged with feature @unstable. Their >> name *may* start with 'x-' to help human users, at the cost of renames >> when the member becomes stable. >> > > Hi Markus, > > Thank you very much for the warning. I'll add the unstable feature tag. > > If I understood correctly this needs to be done as x-perf at > BackupCommon struct. Could you confirm to me that it marks only the > x-perf member as unstable? Without reading the actual comment it might > seem as if it marks all the whole BackupCommon struct as unstable. > > # ... > # @filter-node-name: the node name that should be assigned to the > # filter driver that the backup job inserts into the g= raph > # above node specified by @drive. If this option is > not given, > # a node name is autogenerated. (Since: 4.2) > # > # @x-perf: Performance options. (Since 6.0) > # > # Features: > # @unstable: Member @x-perf is experimental. > # > # Note: @on-source-error and @on-target-error only affect background > # I/O. If an error occurs during a guest write request, the device= 's > # rerror/werror actions will be used. > # > # Since: 4.2 > ## > { 'struct': 'BackupCommon', > 'data': { ... > '*filter-node-name': 'str', > '*x-perf': { 'type': 'BackupPerf', > 'features': [ 'unstable' ] } } } This tacks features to member @x-perf, i.e. they apply just to member @x-perf. Features can also be tacked to the struct type, like this: { 'struct': 'BackupCommon', 'data': { ... '*filter-node-name': 'str', '*x-perf': 'BackupPerf' }, 'features': [ 'unstable' ] } Now they apply to type BackupCommon as a whole. BlockdevOptionsFile in block-core.json actually makes use of both ways: { 'struct': 'BlockdevOptionsFile', 'data': { 'filename': 'str', '*pr-manager': 'str', '*locking': 'OnOffAuto', '*aio': 'BlockdevAioOptions', '*aio-max-batch': 'int', '*drop-cache': {'type': 'bool', 'if': 'CONFIG_LINUX'}, '*x-check-cache-dropped': { 'type': 'bool', 'features': [ 'unstable' ] } }, 'features': [ { 'name': 'dynamic-auto-read-only', 'if': 'CONFIG_POSIX' } ] } Feature @dynamic-auto-read-only applies to the type, and feature @unstable applies to member @x-check-cache-dropped. Questions?