From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53995) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zr42e-0005U8-IN for qemu-devel@nongnu.org; Tue, 27 Oct 2015 09:11:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Zr42b-0007NO-Bi for qemu-devel@nongnu.org; Tue, 27 Oct 2015 09:11:56 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57708) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zr42b-0007NB-6G for qemu-devel@nongnu.org; Tue, 27 Oct 2015 09:11:53 -0400 References: <014501d10fec$8b2548b0$a16fda10$@samsung.com> <562E5D60.7060501@redhat.com> <00b801d11086$47049600$d50dc200$@samsung.com> From: Eric Blake Message-ID: <562F7812.2030501@redhat.com> Date: Tue, 27 Oct 2015 07:11:46 -0600 MIME-Version: 1.0 In-Reply-To: <00b801d11086$47049600$d50dc200$@samsung.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="LM6mrq3QLaDnPFdwUuq3uak1cunlQFJC9" Subject: Re: [Qemu-devel] [PATCH] migration: Introduce MIGRATION_STATUS_FINISHING List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Pavel Fedin , qemu-devel@nongnu.org Cc: 'Amit Shah' , 'Juan Quintela' , 'Luiz Capitulino' This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --LM6mrq3QLaDnPFdwUuq3uak1cunlQFJC9 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 10/27/2015 01:08 AM, Pavel Fedin wrote: > Hello! >=20 >> adding new user-visible states >> has a tendency to break existing clients that aren't prepared for >> unexpected states (although technically such bugs are in the client - = in >> the past, libvirt used to be one such client, although we've tried to >> fix it to gracefully ignore unknown states). >=20 > Yes, i know this, my host uses libvirt v1.2.9.3 (i backport necessary = patches to it) and it barfed. I didn't check master though... >=20 >> Are we sure no other >> existing state works for this? I'm not opposed to the addition, just >> wanting to make sure we have good reason for it. >=20 > You know, actually, this is a thing only for qemu's internal use, we d= on't need a new state at all. Instead, we could introduce a 'bool cpus_st= opped' to MigrationState structure and test for it in migration_in_finish= ing(), like: > --- cut --- > bool migration_in_finishing(MigrationState *s) > { > return s->cpus_stopped; > } > --- cut --- > What do you think about this solution? It is much less complicated tha= n... If it is truly internal, then avoiding exposing the state to external clients is indeed the way to go. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --LM6mrq3QLaDnPFdwUuq3uak1cunlQFJC9 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/ iQEcBAEBCAAGBQJWL3gSAAoJEKeha0olJ0NqrTMIAIKdZH6zwSs6ZPAMf+mFO7ww KXSmvoEAakqX+wFWts4KV4+RNhLBQSw0t0GrUTLq6+cw/boqxoTss4ZF/jEtDARi TZ0xz5OJvrE3p9N/jy24m9TMBQeMKX1zB6zTubxhQL3NRkF3qnAD0ecElIgkJbHx fGoOfNwKoQcu+kJgWj18iBuHN/tZ2iKBXHqvF6NqSqVrnJ58NA2Jt52yPCJh2EVH O9Y1Iog9XSnJnbU89u/JHVtkndVcFTZobci0JeKH7RsmKwtRtfOaMXR95SUvDWZI DhGpBugCP9b9Po1SvfridowIttO4lSkFXU/yRbn6/M6XTspTsamrnSmOux06uwk= =4/OX -----END PGP SIGNATURE----- --LM6mrq3QLaDnPFdwUuq3uak1cunlQFJC9--