From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59869) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bGI7Z-0008Ar-Fv for qemu-devel@nongnu.org; Thu, 23 Jun 2016 23:49:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bGI7T-00022D-DN for qemu-devel@nongnu.org; Thu, 23 Jun 2016 23:49:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45774) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bGI7T-000223-5F for qemu-devel@nongnu.org; Thu, 23 Jun 2016 23:49:27 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 59983461C3 for ; Fri, 24 Jun 2016 03:49:26 +0000 (UTC) References: <6a52d9a67cc72abb874c9906df039d11bfe1e18d.1466713052.git.pkrempa@redhat.com> <20160624125617.54dc1fc9@voom.fritz.box> From: Eric Blake Message-ID: <576CADC5.6020602@redhat.com> Date: Thu, 23 Jun 2016 21:49:25 -0600 MIME-Version: 1.0 In-Reply-To: <20160624125617.54dc1fc9@voom.fritz.box> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="hTSELhwTu4gtthRugKAjE37ti2pwxSm69" Subject: Re: [Qemu-devel] [PATCH 1/3] qapi: Report support for -device cpu hotplug in query-machines List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: David Gibson , Peter Krempa Cc: Igor Mammedov , qemu-devel@nongnu.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --hTSELhwTu4gtthRugKAjE37ti2pwxSm69 From: Eric Blake To: David Gibson , Peter Krempa Cc: Igor Mammedov , qemu-devel@nongnu.org Message-ID: <576CADC5.6020602@redhat.com> Subject: Re: [Qemu-devel] [PATCH 1/3] qapi: Report support for -device cpu hotplug in query-machines References: <6a52d9a67cc72abb874c9906df039d11bfe1e18d.1466713052.git.pkrempa@redhat.com> <20160624125617.54dc1fc9@voom.fritz.box> In-Reply-To: <20160624125617.54dc1fc9@voom.fritz.box> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 06/23/2016 08:56 PM, David Gibson wrote: > On Thu, 23 Jun 2016 22:23:23 +0200 > Peter Krempa wrote: >=20 >> For management apps it's very useful to know whether the selected >> machine type supports cpu hotplug via the new -device approach. Using >> the presence of 'query-hotpluggable-cpus' is enough for a withess. >> >=20 > I'd been under the impression that there was a general way of detecting= > the availability of a particular qmp command. Was I mistaken? You are correct - query-commands says whether 'query-hotpluggable-cpus' exists as a command. But that is insufficient. See my review, or the v2 patch, where the above poor wording was corrected to say what was really meant: knowing whether query-hotpluggable-cpus exists is insufficient to tell you whether a given cpu type can be hotplugged. So adding one more piece of witness (for every type of cpu supported, we also advertise if it is hotpluggable) is enough for libvirt to efficiently take advantage of the new query-hotpluggable-cpus command. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --hTSELhwTu4gtthRugKAjE37ti2pwxSm69 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJXbK3FAAoJEKeha0olJ0NqiNgH/2yNS4JLSIdGEz+Tqf9o/UMV LdQ87SGUt15rR+R8UJCqptvD5Iib/yOYCUV+TONCw0U0dQ0XcV+sKvt7piFohA5J zjREVICUiYvqqFTE3Mek5ZdGseeROxKNdbSRMG8O3E9JrCK06rI/pjdDMHCULVGm ARRGfSqZ94/pGBnXhetx4Axo3WrXDqIp+lhfQ4oy3UXFpEHpLg8ZI07CSnhmt5Kh lfucAmQCzvAQ3zqHMTVoOUEfxIj/AH1VK77ZSQmwQYgMeuUaxYW3BtR5QjhspG/l 4nzuIAvrPC5f4t2eZDB1sYmgdOmoSoenrD2IHvCt9hQ9J48oyx53+443HgEFi2w= =4+DF -----END PGP SIGNATURE----- --hTSELhwTu4gtthRugKAjE37ti2pwxSm69--