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=-11.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 93654C4727C for ; Tue, 29 Sep 2020 13:09:23 +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 0BB3820848 for ; Tue, 29 Sep 2020 13:09:23 +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="hXd323rW" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0BB3820848 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]:51740 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kNFNi-0004mB-2s for qemu-devel@archiver.kernel.org; Tue, 29 Sep 2020 09:09:22 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60792) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kNFMD-0003DK-LX for qemu-devel@nongnu.org; Tue, 29 Sep 2020 09:07:50 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:59041) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kNFMB-0004oR-09 for qemu-devel@nongnu.org; Tue, 29 Sep 2020 09:07:49 -0400 Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1601384865; 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=Bh5+rFpDlwWIGJXDQ7F+rsB5fJEu4LPWKzjd45Zyx+M=; b=hXd323rWvhav9J5j/DehWs5BargS4ZNNzrh3+A15SK5jQ40x46jY6TB1y9WnY/8im/b2BS GPtOXPH5RIAAs76Yz/SEPsYgq4opsFOPD1dtILwLTpUOUB00jkT634Y+7diOzETN0WWWMv VWqR0Q3OauwePWHh6KOzJwcLZr80N9E= 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-444-l3mfjjPCNLC0e3lCXzOQyA-1; Tue, 29 Sep 2020 09:07:43 -0400 X-MC-Unique: l3mfjjPCNLC0e3lCXzOQyA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B31A710BBEC0; Tue, 29 Sep 2020 13:07:42 +0000 (UTC) Received: from [10.3.112.208] (ovpn-112-208.phx2.redhat.com [10.3.112.208]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2FD2360DA0; Tue, 29 Sep 2020 13:07:39 +0000 (UTC) Subject: Re: [PATCH v2 4/4] block/export: add iothread and fixed-iothread options To: Stefan Hajnoczi , qemu-devel@nongnu.org References: <20200929125516.186715-1-stefanha@redhat.com> <20200929125516.186715-5-stefanha@redhat.com> From: Eric Blake Organization: Red Hat, Inc. Message-ID: <7f99e542-c6a1-cec4-26f9-30ce4e271c65@redhat.com> Date: Tue, 29 Sep 2020 08:07:38 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <20200929125516.186715-5-stefanha@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eblake@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/28 22:47:55 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.687, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable 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 , Laurent Vivier , Thomas Huth , qemu-block@nongnu.org, Markus Armbruster , Coiby Xu , Max Reitz , Paolo Bonzini Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 9/29/20 7:55 AM, Stefan Hajnoczi wrote: > Make it possible to specify the iothread where the export will run. By > default the block node can be moved to other AioContexts later and the > export will follow. The fixed-iothread option forces strict behavior > that prevents changing AioContext while the export is active. See the > QAPI docs for details. > > Signed-off-by: Stefan Hajnoczi > --- > Note the x-blockdev-set-iothread QMP command can be used to do the same, > but not from the command-line. And it requires sending an additional > command. > > In the long run vhost-user-blk will support per-virtqueue iothread > mappings. But for now a single iothread makes sense and most other > transports will just use one iothread anyway. > --- > qapi/block-export.json | 11 ++++++++++ > block/export/export.c | 31 +++++++++++++++++++++++++++- > block/export/vhost-user-blk-server.c | 5 ++++- > nbd/server.c | 2 -- > 4 files changed, 45 insertions(+), 4 deletions(-) > > diff --git a/qapi/block-export.json b/qapi/block-export.json > index 87ac5117cd..e2cb21f5f1 100644 > --- a/qapi/block-export.json > +++ b/qapi/block-export.json > @@ -219,11 +219,22 @@ > # export before completion is signalled. (since: 5.2; > # default: false) > # > +# @iothread: The name of the iothread object where the export will run. The > +# default is to use the thread currently associated with the # Stray # > +# block node. (since: 5.2) > +# > +# @fixed-iothread: True prevents the block node from being moved to another > +# thread while the export is active. If true and @iothread is > +# given, export creation fails if the block node cannot be > +# moved to the iothread. The default is false. > +# Missing a '(since 5.2)' tag. (Hmm, we're inconsistent on whether it is 'since 5.2' or 'since: 5.2' inside () parentheticals; Markus, is that something we should be cleaning up as part of the conversion to rST?) > @@ -63,10 +64,11 @@ static const BlockExportDriver *blk_exp_find_driver(BlockExportType type) > > BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp) > { > + bool fixed_iothread = export->has_fixed_iothread && export->fixed_iothread; Technically, our QAPI code guarantees that export->fixed_iothread is false if export->has_fixed_iothread is false. And someday I'd love to let QAPI express default values for bools so that we don't need a has_FOO field when a default has been expressed. But neither of those points affect this patch; what you have is correct even if it is verbose. Otherwise looks reasonable. -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org