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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 BEF7DC2D0B1 for ; Thu, 6 Feb 2020 12:17:00 +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 897E820730 for ; Thu, 6 Feb 2020 12:17:00 +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="aiD1HuHA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 897E820730 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]:37726 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1izg5b-0007FE-O1 for qemu-devel@archiver.kernel.org; Thu, 06 Feb 2020 07:16:59 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:34494) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1izg4Z-000674-A9 for qemu-devel@nongnu.org; Thu, 06 Feb 2020 07:15:56 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1izg4X-0002V4-Qn for qemu-devel@nongnu.org; Thu, 06 Feb 2020 07:15:55 -0500 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:39224 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1izg4X-0002Ro-Kn for qemu-devel@nongnu.org; Thu, 06 Feb 2020 07:15:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1580991353; 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=A3ge7caYNgMGGCMIExO1jVAuH7XH6bZcPRYHvvoGOoo=; b=aiD1HuHAmLA9kS60qKgBdhnkm+KiCIqni4FmkkfBvZQYDUxWZxTXuRNEqMK7L+rIfhRy4w NxhsqslOif5oTBk3ldsBYiULclOuPLhvsUmpuVUkeO8wTTJZOXbZkg8Qb+fsb30Qs2gh11 44/VmGhkguAXfkBfcwlsYgGTjF3Vnyk= 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-186-ZfQfz9RzOKGe4mQNlj8CXQ-1; Thu, 06 Feb 2020 07:15:44 -0500 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B03B914E0; Thu, 6 Feb 2020 12:15:43 +0000 (UTC) Received: from redhat.com (ovpn-112-65.ams2.redhat.com [10.36.112.65]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5569526FA8; Thu, 6 Feb 2020 12:15:31 +0000 (UTC) Date: Thu, 6 Feb 2020 12:15:28 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Markus Armbruster Subject: Re: qmp-shell for GSoC/Outreachy? Message-ID: <20200206121528.GG2391707@redhat.com> References: <20200124095027.GA824327@redhat.com> <20200127143505.GD5669@linux.fritz.box> <20200127202925.GE3419@work-vm> <20200128105932.GC6431@linux.fritz.box> <20200205130946.GC5768@dhcp-200-226.str.redhat.com> <20200205194944.GP3210@work-vm> <877e10xdd6.fsf@dusky.pond.sub.org> <20200206100920.GD2391707@redhat.com> <8736bnx6cx.fsf@dusky.pond.sub.org> MIME-Version: 1.0 In-Reply-To: <8736bnx6cx.fsf@dusky.pond.sub.org> User-Agent: Mutt/1.13.3 (2020-01-12) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: ZfQfz9RzOKGe4mQNlj8CXQ-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.120 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: Kevin Wolf , Peter Maydell , "Denis V. Lunev" , Cleber Rosa , Stefan Hajnoczi , "Dr. David Alan Gilbert" , Eduardo Habkost , qemu-devel , Paolo Bonzini , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , John Snow , Dominik Csapak Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, Feb 06, 2020 at 01:11:58PM +0100, Markus Armbruster wrote: > Daniel P. Berrang=C3=A9 writes: >=20 > > On Thu, Feb 06, 2020 at 10:40:37AM +0100, Markus Armbruster wrote: > >> > If the user screwsup, it should give an error that prompts the user > >> > to the parameter they got wrong. > >> > > >> > Output from commands should normally be pretty formatted (with an op= tion > >> > to display raw json for those needing it). > >> > e.g. that 'query-version' should give either just the package > >> > version (as info version currently does) or: > >> > 4.2.50 Package: v4.2.0-1188-gd95a3885a9 > >> > > >> > We shouldn't lose any HMP commands that some people find useful > >> > Ditching HMP isn't an option until we've got almost all of it > >> > covered. > >>=20 > >> In particular, we currently use HMP for debugging and monitoring > >> purposes, where we don't need or want QMP's rigor, neither its rigorou= s > >> interface stability, nor its structured I/O. We want the "whipuptitud= e" > >> we get from monitor_printf(). This is actually a point David has made > >> several times. > > > > I'd like to argue that this decision to keep these debugging/monitoring > > things in HMP only was a mistake, because it ensures that QEMU internal= s > > need to keep HMP related code forever. > > > > What we actually need is a part of QMP that does not have the long term > > stability requirement, nor need for fully structured data. In fact this > > pretty much already exists - we have declared the 'x-' prefix as a way > > to model QMP commands which are experimental / suboptimal / subject > > to change. > > > > I suggest that every HMP command which does not have a QMP equivalent > > should be turned into a QMP command with an "x-" prefix, with no > > extra modelling applied >=20 > Makes sense (see my point about "allowing some [whipuptitude] in QMP"), > except I disagree with your example: >=20 > > Take "info block" > > > > (hmp) info block > > ide1-cd0: [not inserted] > > Attached to: /machine/unattached/device[23] > > Removable device: not locked, tray closed > > > > floppy0: [not inserted] > > Attached to: /machine/unattached/device[16] > > Removable device: not locked, tray closed > > > > sd0: [not inserted] > > Removable device: not locked, tray closed > > > > > > I suggest we support it as "x-query-block" > > > > (qmp) x-query-block > > { > > "return": { > > "info": "ide1-cd0: [not inserted] > > Attached to: /machine/unattached/device[23] > > Removable device: not locked, tray closed > > > > floppy0: [not inserted] > > Attached to: /machine/unattached/device[16] > > Removable device: not locked, tray closed > > > > sd0: [not inserted] > > Removable device: not locked, tray closed" > > } > > } >=20 > This commmand does have a QMP equivalent: query-block. Doh, I should have actually checked before picking a random example :-) >=20 > Hmm, no more. It actually wraps around both query-block and > query-named-block-nodes now. I think that makes it an example of "go > beyond 1:1". >=20 > A better example for "allowing whipuptitude" would be "info registers". Yep, that's a classic that would be horribly painful to try to represent as a fully structured set of arrays & dicts for all architectures. Regards, Daniel --=20 |: 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= :|