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 E9238C3DA4A for ; Fri, 12 Jul 2024 08:51:29 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sSBze-0007kY-EK; Fri, 12 Jul 2024 04:51:06 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sSBzc-0007cZ-FC for qemu-devel@nongnu.org; Fri, 12 Jul 2024 04:51:04 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sSBza-0003cJ-NZ for qemu-devel@nongnu.org; Fri, 12 Jul 2024 04:51:04 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1720774260; 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=L5kyceAxXyZqcIxRAamUJLp8BO2co/1kbuTBzG3Kvuo=; b=TikFQ5giENEjwnouSx0eJ/YSIvLOecoItmlHzx0xRSn1B/2c8PEhVs4vwp6rKW4KlsnbOx 0p+GbbwGEAXM/uU1mCpNTQisZAqxzvYw/+3AKRLK9LVpiiD/1kr1OOpYHzx++CPWWQIcbX /2xZCpDmg9dDyhMWcfQ5jbn4WeT65NY= Received: from mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-294-QjA-Ru4aOGO0Hr8oawhGkQ-1; Fri, 12 Jul 2024 04:50:58 -0400 X-MC-Unique: QjA-Ru4aOGO0Hr8oawhGkQ-1 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 1FB43195419C; Fri, 12 Jul 2024 08:50:57 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.192.4]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 9F97319560AE; Fri, 12 Jul 2024 08:50:56 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 66F7921E668C; Fri, 12 Jul 2024 10:50:54 +0200 (CEST) From: Markus Armbruster To: Daniel P. =?utf-8?Q?Berrang=C3=A9?= Cc: qemu-devel@nongnu.org, Michael Roth , Konstantin Kostiuk Subject: Re: [PATCH 04/14] qapi: add a 'command-features' pragma In-Reply-To: ("Daniel P. =?utf-8?Q?Berrang?= =?utf-8?Q?=C3=A9=22's?= message of "Fri, 12 Jul 2024 09:12:59 +0100") References: <20240604153242.251334-1-berrange@redhat.com> <20240604153242.251334-5-berrange@redhat.com> <87r0bzuj7d.fsf@pond.sub.org> Date: Fri, 12 Jul 2024 10:50:54 +0200 Message-ID: <87a5inuh75.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.142, 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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, 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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Daniel P. Berrang=C3=A9 writes: > On Fri, Jul 12, 2024 at 10:07:34AM +0200, Markus Armbruster wrote: >> Daniel P. Berrang=C3=A9 writes: >>=20 >> > The 'command-features' pragma allows for defining additional >> > special features that are unique to a particular QAPI schema >> > instance and its implementation. >>=20 >> So far, we have special features (predefined, known to the generator and >> treated specially), and normal features (user-defined, not known to the >> generator). You create a new kind in between: user-defined, not known >> to the generator, yet treated specially (I guess?). Hmm. >>=20 >> Could you at least hint at indented use here? What special treatment do >> you have in mind? > > Essentially, these features are a way to attach metadata to commands that > the server side impl can later query. This eliminates the need to hardcode > lists of commands, such as in QGA which hardcodes a list of commands which > are safe to use when filesystems are frozen. This is illustrated later in > this series. Please update docs/devel/qapi-code-gen.rst section "Pragma directives", and maybe section "Features". I'm not sure conflating the new kind of feature with existing special features is a good idea. I need to review more of the series before I can make up my mind.