From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35191) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fXSzJ-0006CB-4U for qemu-devel@nongnu.org; Mon, 25 Jun 2018 11:01:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fXSzF-0006AH-7S for qemu-devel@nongnu.org; Mon, 25 Jun 2018 11:01:05 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:43658 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fXSzF-00069L-1B for qemu-devel@nongnu.org; Mon, 25 Jun 2018 11:01:01 -0400 Date: Mon, 25 Jun 2018 16:00:57 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20180625150056.GF2390@work-vm> References: <20180601153922.11590-1-ricardo.perez_blanco@nokia.com> <20180608094101.GG2671@work-vm> <0cc71e01-7015-8f8b-6988-d3b411d3b28c@suse.de> <87y3fky231.fsf@dusky.pond.sub.org> <87h8lrumny.fsf@dusky.pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <87h8lrumny.fsf@dusky.pond.sub.org> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v2] Show values and description when using "qom-list" List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Markus Armbruster Cc: Andreas =?iso-8859-1?Q?F=E4rber?= , Ricardo Perez Blanco , qemu-devel , Dongli Zhang * Markus Armbruster (armbru@redhat.com) wrote: > Markus Armbruster writes: >=20 > > Andreas F=E4rber writes: > > > >> Am 08.06.2018 um 11:41 schrieb Dr. David Alan Gilbert: > >>> * Andreas F=E4rber (afaerber@suse.de) wrote: > >>>> Am 01.06.2018 um 17:39 schrieb Ricardo Perez Blanco: > >>>>> For debugging purposes it is very useful to: > >>>>> - See the description of the field. This information is already = filled > >>>>> in but not shown in "qom-list" command. > >>>> > >>>> No objection on this part. > >>>> > >>>>> - Display value of the field. > >>>> > >>>> That is by definition the qom-get operation, not qom-list. Just li= ke the > >>>> ls command does not show file contents, there's cat etc. for that.= For > >>>> debugging purposes we had a qom-tree (?) command that would combin= e > >>>> both. > >>> > >>> I'm not too bothered about distinguishing between the two commands; > >>> but it would be nice > > > > When an HMP and QMP both have a command with the same name, they shou= ld > > do the same. > > > > HMP may add convenience features that aren't wanted in QMP, but I fee= l > > extending an operation to list objects to also show their contents go= es > > beyond that. If we want an HMP command that does both, it should be > > named differently. Perhaps that might even be more appropriate for H= MP > > than low-level commands qom-list and qom-get, but I leave that to the > > HMP maintainer to decide. > > > >>> - one reason I'm not too bothered is because w= e've > >>> failed to get a qom-get in multiple years of trying. > > > > We clearly haven't tried hard enough. > > > > If we can figure out how to show values in qom-list, surely we can > > figure out how to show them in qom-get. > > > >>>> There might be unmerged patches on qemu-devel related to dis= play > >>>> of certain data types. > >>>=20 > >>> Which ones? > >> > >> My original qom-info series needed StringOutputVisitor changes for e= nums > >> (test case: rtc) that did not get accepted immediately and thus some > >> part of HMP qom-info/qom-get got stuck due to risking assertions for > >> qom-info / otherwise; QMP was not affected IIRC. > > > > Here's the last try I can find: > > [PATCH v2] qom: Implement qom-get HMP command > > Message-Id: <1473157086-12062-1-git-send-email-dgilbert@redhat.com> > > https://lists.gnu.org/archive/html/qemu-devel/2016-09/msg01041.html >=20 > Stalled on output format and consistency with qom-set. I wrote back > then "We can take qom-get as is and improve its output later." I'd lik= e > to encourage you to dust it off. Perfect's the enemy of good. >=20 > Wanted improvements include: >=20 > * Prettier output format. I'd suggest creating a keyval variant of the > output visitor. I'm not too bothered about pretty at first, as long as we don't stop anyway of making it pretty later; especially if non-compound types work well. > * Make qom-set input format consistent by switching to the matching > input visitor. >=20 > > Its v1 tries a different approach: > > [PATCH 0/2] qom-get [for 2.8] > > Message-Id: <1472117833-10236-1-git-send-email-dgilbert@redhat.com> > > Unfortunately the mailing list archive doesn't show the full thread, = so > > you get to follow three links: > > https://lists.gnu.org/archive/html/qemu-devel/2016-08/msg03815.html > > https://lists.gnu.org/archive/html/qemu-devel/2016-09/msg04261.html > > https://lists.gnu.org/archive/html/qemu-devel/2016-09/msg04267.html >=20 > This one stalled on string visitor limitations. You didn't feel like > addressing them just to get qom-get working. Understandable. Have there been any changes in the last 2 years that have helped? Dave -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK