From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56488) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cb8eK-0003Ve-Jg for qemu-devel@nongnu.org; Tue, 07 Feb 2017 11:29:49 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cb8eH-0004UV-Ca for qemu-devel@nongnu.org; Tue, 07 Feb 2017 11:29:48 -0500 Received: from 10.mo179.mail-out.ovh.net ([46.105.79.46]:34816) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cb8eH-0004TY-6F for qemu-devel@nongnu.org; Tue, 07 Feb 2017 11:29:45 -0500 Received: from player732.ha.ovh.net (b7.ovh.net [213.186.33.57]) by mo179.mail-out.ovh.net (Postfix) with ESMTP id B207D21A77 for ; Tue, 7 Feb 2017 17:29:42 +0100 (CET) Date: Tue, 7 Feb 2017 17:29:33 +0100 From: Greg Kurz Message-ID: <20170207172933.05574f60@bahia.lan> In-Reply-To: <6b702369-7891-4e38-7240-57ad643657bd@redhat.com> References: <1486123043-26493-1-git-send-email-pradeep.jagadeesh@huawei.com> <1486123043-26493-2-git-send-email-pradeep.jagadeesh@huawei.com> <71b1733d-7638-5e27-e828-fad57f76f507@redhat.com> <20170207001533.3f18e4ea@bahia.lan> <20170207113231.44e35be6@bahia.lan> <6b702369-7891-4e38-7240-57ad643657bd@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/7nO+FYEDC9WBP+Ini.Z96S_"; protocol="application/pgp-signature" Subject: Re: [Qemu-devel] [PATCH 1/2 v16] fsdev: add IO throttle support to fsdev devices List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Blake Cc: Pradeep Jagadeesh , "Aneesh Kumar K.V" , Alberto Garcia , Pradeep Jagadeesh , qemu-devel@nongnu.org, Stefan Hajnoczi --Sig_/7nO+FYEDC9WBP+Ini.Z96S_ Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Cc'ing Stefan who reviewed patch 2/2. On Tue, 7 Feb 2017 09:56:08 -0600 Eric Blake wrote: > On 02/07/2017 04:32 AM, Greg Kurz wrote: > >> > >> I'm not aware of anything related to fsdev in QMP... and libvirt seems= to > >> only parse the output of -help to guess fsdev capabilities. =20 > >=20 > > Oops, reading some more libvirt code I now see that libvirt doesn't par= se > > -help anymore with QEMU >=3D 1.2.0... sorry for the noise :) > > =20 > >> And indeed, > >> qemu-options.hx doesn't expose this new feature. > >> =20 > >>> Please make sure we don't reach 2.9 with only a half-baked feature; > >>> whether that means finishing the QMP work or temporarily disabling the > >>> cli additions until a later release can finish the work. > >>> =20 > >> > >> Would this be ok to add the missing bits in qemu-options.hx or do you > >> expect more ? =20 >=20 > If it cannot be probed via QMP, then libvirt will most likely assume > that it does not exist. I guess we're okay having command line only in > 2.9 if you can't get QMP working, because libvirt will just never drive > the feature until 2.10 when QMP is available; but then we risk the > command line subtly changing and breaking someone else that was using > the command line without QMP. Maybe the safest approach is to just use > the 'x-' prefix to the command line portion, until the feature is complet= e. >=20 The semantics here are exactly the same as for block devices. The command line options added to -fsdev are the very same already used by -drive for years. Patch 2/2 in this series even factors them out to a common header file to be used by fsdev and blockdev. I really don't expect any modification at all on the command line (nor the other people who reviewed that patch obviously)... are you suggesting that we should put 2/2 on hold and use the 'x-' prefix anyway ? Cheers. -- Greg --Sig_/7nO+FYEDC9WBP+Ini.Z96S_ Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iEYEARECAAYFAliZ9e0ACgkQAvw66wEB28IKdgCgi1e6649v+OiwCHGtduPat9Gf ilIAn1PwN+ZEQaCAGYB5RzosqedRDNYJ =1XZX -----END PGP SIGNATURE----- --Sig_/7nO+FYEDC9WBP+Ini.Z96S_--