From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36968) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dWwNB-00008s-GZ for qemu-devel@nongnu.org; Sun, 16 Jul 2017 23:07:02 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dWwN8-0004I0-7t for qemu-devel@nongnu.org; Sun, 16 Jul 2017 23:07:01 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58854) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dWwN8-0004Gi-1l for qemu-devel@nongnu.org; Sun, 16 Jul 2017 23:06:58 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B60984E4D6 for ; Mon, 17 Jul 2017 03:06:56 +0000 (UTC) Date: Mon, 17 Jul 2017 11:06:57 +0800 From: Peter Xu Message-ID: <20170717030657.GS27284@pxdev.xzpeter.org> References: <1499842423-21101-1-git-send-email-peterx@redhat.com> <20170712190558.GK6020@localhost.localdomain> <20170714050423.GM27284@pxdev.xzpeter.org> <20170714160110.GF6020@localhost.localdomain> <20170714163210.GE2091@work-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20170714163210.GE2091@work-vm> Subject: Re: [Qemu-devel] [PATCH 0/3] migration: export cap/params to qdev props List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Dr. David Alan Gilbert" Cc: Eduardo Habkost , qemu-devel@nongnu.org, Laurent Vivier , Markus Armbruster , Juan Quintela On Fri, Jul 14, 2017 at 05:32:10PM +0100, Dr. David Alan Gilbert wrote: > * Eduardo Habkost (ehabkost@redhat.com) wrote: > > On Fri, Jul 14, 2017 at 01:04:23PM +0800, Peter Xu wrote: > > > On Wed, Jul 12, 2017 at 04:05:58PM -0300, Eduardo Habkost wrote: > > > > On Wed, Jul 12, 2017 at 02:53:40PM +0800, Peter Xu wrote: > > > > [...] > > > > > These properties should only be used for debugging/testing purpose, > > > > > and we should not guarantee any interface compatibility for them (just > > > > > like HMP). > > > > > > > > If we don't guarantee compatibility, the property names need to > > > > be prefixed with "x-". > > > > > > Indeed. Sorry I missed that. > > > > > > But I'd say it is slightly awkward to add "x-" for all these (for me, > > > "x-" means more like "this is not stable and experimental, use it > > > carefully", while this does not suite for this series). Maybe I can > > > just remove this sentence in commit log (I think I am just a little > > > bit frightened by the compatibility problems)... > > > > "x-" in property names doesn't mean "experimental", but just "not > > part of the stable interface". If you have the tiniest doubt > > about command-line compatibility, I think it won't hurt to use > > "x-". > > We have: > DEFINE_PROP_MIG_CAP("xbzrle", MIGRATION_CAPABILITY_XBZRLE), > > so we could easily do: > DEFINE_PROP_MIG_CAP("x-xbzrle", MIGRATION_CAPABILITY_XBZRLE), > > to ensure that all of the things we expose as props here have > that added fealing of uncertainty but don't change what migration > parameters see. I was thinking to ask either you or Juan on what you would like for this, looks like I got the answer now. :-) Let me add "x-" to them. > > > (It's a shame we have to have those lists manually, there are so > many manual places for each parameter and capability) Temporarily I think it's still okay. But indeed you are right. -- Peter Xu