From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56131) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YGtAq-0005sf-Fd for qemu-devel@nongnu.org; Thu, 29 Jan 2015 12:46:37 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YGtAn-0003TN-9n for qemu-devel@nongnu.org; Thu, 29 Jan 2015 12:46:36 -0500 Received: from cantor2.suse.de ([195.135.220.15]:37139 helo=mx2.suse.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YGtAm-0003TF-VL for qemu-devel@nongnu.org; Thu, 29 Jan 2015 12:46:33 -0500 Message-ID: <54CA71F6.8060405@suse.de> Date: Thu, 29 Jan 2015 18:46:30 +0100 From: =?ISO-8859-15?Q?Andreas_F=E4rber?= MIME-Version: 1.0 References: <1420697420-16053-1-git-send-email-bharata@linux.vnet.ibm.com> In-Reply-To: <1420697420-16053-1-git-send-email-bharata@linux.vnet.ibm.com> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="24KgK3kWj1RAhH3BhGr1Jb3Dan89O0Lt8" Subject: Re: [Qemu-devel] [RFC PATCH v1 00/13] CPU and Memory hotplug for PowerPC guests List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Bharata B Rao , qemu-devel@nongnu.org Cc: imammedo@redhat.com, mdroth@linux.vnet.ibm.com, agraf@suse.de This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --24KgK3kWj1RAhH3BhGr1Jb3Dan89O0Lt8 Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: quoted-printable Hi, Am 08.01.2015 um 07:10 schrieb Bharata B Rao: > This patchset enables CPU and memory hotplug support for PowerPC guests= =2E >=20 > Changes in this patchset (v1): >=20 > - Based on top of Michael Roth's tree > (https://github.com/mdroth/qemu/commits/spapr-hotplug-core) which ser= ves > as base for his PCI hotplug patches too. > - Switched to device_add/del semantics instead of cpu-add. Please don't forget to CC me on this. As previously discussed with Jason and Christian for s390x, there's certain topology modeling questions still unsolved for device-based QOM CPU hot-plug. I have an RFC in the works (again) that hopefully gets us a step closer. > - Supporting CPU hot unplug now. > - Added patches to enable memory hotplug. > - Added ibm,dynamic-reconfiguration-memory support which is needed for > memory hotplug. >=20 > v0 - http://lists.nongnu.org/archive/html/qemu-devel/2014-09/msg00752.h= tml >=20 > CPU hotplug > ----------- > - Works with BE guest, has issues with LE guest. Has been tested on BE = host > only. > - Adding a core (and all its threads) in response to device_add command= =2E > Similarly removing a core via device_del will remove all the threads.= Earlier discussions concluded that hot-plug needs to happen on a socket level, not core. If you're assuming the socket to have one core (as we were planning for s390x), that doesn't make much of a difference number-wise, but it does in modeling terms. Think what you can physically plug onto the mainboard, that's the granularity that realized=3Dtrue/false is going to operate on. A virtual socket may well correspond to a thread on some socket/node of the host, but you cannot add threads to a core or cores to a chip at runtime. On x86 this may become a functional limitation of what is possible through cpu-add, so better avoid that mistake for ppc from the start. Regards, Andreas > - Using Gu Zheng's "reclaim vCPU objects" patch to remove and reuse > the vCPU objects after CPUs removal. > (Gu Zheng's original patch: > http://lists.gnu.org/archive/html/qemu-devel/2014-12/msg01829.html) [snip] --=20 SUSE Linux GmbH, Maxfeldstr. 5, 90409 N=FCrnberg, Germany GF: Felix Imend=F6rffer, Jane Smithard, Jennifer Guild, Dilip Upmanyu, Graham Norton; HRB 21284 (AG N=FCrnberg) --24KgK3kWj1RAhH3BhGr1Jb3Dan89O0Lt8 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 iQIcBAEBAgAGBQJUynH2AAoJEPou0S0+fgE/nWYQAKP9md33QnmdUpD+Cv01s3C4 7Dm1sgi2bdYL9PmYU3jdPMoctBupoIvPl3x5mEMBHASx1MLXXw76ttmyR2aa8d0b EhjTe+/0XXu3XuVQgESsDVPJoyJbStwA0noz3u42E7W6FxWtz+dvb9DqHdf144DC +4jTw9wSG1T+5daLeBLmkpkHZ2A+E1ocDaw1tVJntvWGfBVUgtUr9wiHku4k61II 5xZHJmm3RjH+2JJuMa+zjSY7AJL+vVHplU5B19WYMc++QkcY2p4GeQZxv1PIHT6n PQ6hmHMUcIc08HL/MjOECVFbf97/1pYGIWxC5rMmh7rnOOF8Vnpd8/BUhYCLpkck qbHP55aOu8KVHJWGQri7T6eLf6XWRxnn/51HA7Xr4NsennKAJRbwxuxUi9frM6Cd 5973ug/tFgybctnIPlOQb7NoSPnEnRmL2W0Zs+f//2oAUhSl+v5yzoKQjG2If62I gJXwZcPg3frRjeRie+4aaciQCCEMSqReWC5RoAely3RGQWGKRGWd5Dpi/sb/XDan gvdzx25a0ovswepYlAmOg7Yu+hXv342fbG+KjyOsEE3Cj/Jd5Zj90HTNyBjiKVV5 uoAZaSGfolqniAAAfhwNkT1+3vrmSc40S5GWtej2IijaFYeiOuwTFfNsUJ1yk7lf F1UhlkUrpc54GW8Tm08v =lo+P -----END PGP SIGNATURE----- --24KgK3kWj1RAhH3BhGr1Jb3Dan89O0Lt8--