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 14A99C433EF for ; Mon, 25 Apr 2022 11:21:07 +0000 (UTC) Received: from localhost ([::1]:56738 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1niwmA-0003fA-Ui for qemu-devel@archiver.kernel.org; Mon, 25 Apr 2022 07:21:06 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48572) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1niwkQ-0002qF-IN for qemu-devel@nongnu.org; Mon, 25 Apr 2022 07:19:18 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:34348) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1niwkN-0005k0-Ns for qemu-devel@nongnu.org; Mon, 25 Apr 2022 07:19:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1650885555; h=from:from:reply-to: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=kWdr+NtWhvmycSC/eKoqMYxhaGW3gcReeLJKiCg1uIY=; b=FuHZw7lk5P8m10Cq+7uDvp5Wo+9jlifsHXeqkEdSC9M6LnhSW9V28arJUKFR+GtH0IpsxY icOF0Z56TZjMU+lgVJXXfp8KiTqFylKtS0KLHhTP223nLmvXfQLXj2WvC0yTQuWv3NwTBj k/3yV4oXlxLIJKn+GvhyGU2YQmNcuAI= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-287-QffNzp5yNCi4duNdTQHtuQ-1; Mon, 25 Apr 2022 07:19:11 -0400 X-MC-Unique: QffNzp5yNCi4duNdTQHtuQ-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 75710800882; Mon, 25 Apr 2022 11:19:11 +0000 (UTC) Received: from redhat.com (unknown [10.33.36.152]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AFDA3464DE1; Mon, 25 Apr 2022 11:19:10 +0000 (UTC) Date: Mon, 25 Apr 2022 12:19:08 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Eric Blake Subject: Re: [PATCH v2] Only advertise aio=io_uring if support is actually available Message-ID: References: <20220421165048.12608-1-dmueller@suse.de> <20220421192755.eksb7rfapjsw7qmb@redhat.com> <20220422203046.dd6mc36buja3eusm@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20220422203046.dd6mc36buja3eusm@redhat.com> User-Agent: Mutt/2.1.5 (2021-12-30) X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@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, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=unavailable 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: Dirk =?utf-8?Q?M=C3=BCller?= , qemu-block@nongnu.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Fri, Apr 22, 2022 at 03:30:46PM -0500, Eric Blake wrote: > On Thu, Apr 21, 2022 at 02:27:55PM -0500, Eric Blake wrote: > > On Thu, Apr 21, 2022 at 06:50:48PM +0200, Dirk Müller wrote: > > > Change --help output for aio option to only list the aio backend options that > > > are actually available. io_uring is an optional, linux only backend > > > option so hide it for cases where it isn't there. > > > > As pointed out by Dan, this commit message is not quite accurate. It > > hides only one of the two conditional options, but 'native' is also a > > Linux-only optional backend (CONFIG_LINUX_AIO). > > Stepping back a bit - we already said that making --help > machine-parseable is a non-goal, and so the intent of this patch is > for human readers. But adding an #ifdef ladder to show all 4 possible > combinations gets hairy; adding another option turns it into 8 > combinations. Is there a better way > > What if we just document ALL strings possible in at least one build > (no #ifdef ladder in the help text), but add --aio=help as a way to do > a runtime list of which aio modes are understood by THIS build? It > would match how we have --device=help for qemu proper, and may even be > able to reuse some of that framework code (for parsing out when help > is requested). Did you literally mean '--aio=help' ? 'aio' is just an option for disks, and I don't think we want new top levelk options. So would have to be '-drive ....,aio=help', or '--blockdev ....aio=help' the latter gets tricky with nested json syntax though, so not sure it is nicer. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|