From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44161) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bLPTc-0006lv-3w for qemu-devel@nongnu.org; Fri, 08 Jul 2016 02:41:29 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bLPTY-0002ro-09 for qemu-devel@nongnu.org; Fri, 08 Jul 2016 02:41:27 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:54914 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bLPTX-0002rN-RC for qemu-devel@nongnu.org; Fri, 08 Jul 2016 02:41:23 -0400 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u686cu9Q142794 for ; Fri, 8 Jul 2016 02:41:21 -0400 Received: from e28smtp04.in.ibm.com (e28smtp04.in.ibm.com [125.16.236.4]) by mx0b-001b2d01.pphosted.com with ESMTP id 2415xngkaa-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Fri, 08 Jul 2016 02:41:20 -0400 Received: from localhost by e28smtp04.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 8 Jul 2016 12:11:17 +0530 Date: Fri, 8 Jul 2016 12:11:12 +0530 From: Bharata B Rao Reply-To: bharata@linux.vnet.ibm.com References: <1467903025-13383-1-git-send-email-bharata@linux.vnet.ibm.com> <1467903025-13383-4-git-send-email-bharata@linux.vnet.ibm.com> <20160708052413.GM14675@voom.fritz.box> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160708052413.GM14675@voom.fritz.box> Message-Id: <20160708064112.GK25522@in.ibm.com> Subject: Re: [Qemu-devel] [RFC PATCH v2 3/5] spapr: Set stable_cpu_id for threads of CPU cores List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: David Gibson Cc: qemu-devel@nongnu.org, qemu-ppc@nongnu.org, imammedo@redhat.com, groug@kaod.org, nikunj@linux.vnet.ibm.com, pbonzini@redhat.com On Fri, Jul 08, 2016 at 03:24:13PM +1000, David Gibson wrote: > On Thu, Jul 07, 2016 at 08:20:23PM +0530, Bharata B Rao wrote: > > Conditonally set stable_cpu_id for CPU threads that are created as part > > of spapr CPU cores. The use of stable_cpu_id is enabled for pseries-2.7 > > onwards. > > > > Signed-off-by: Bharata B Rao > > --- > > hw/ppc/spapr_cpu_core.c | 7 +++++++ > > 1 file changed, 7 insertions(+) > > > > diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c > > index b104778..0ec3513 100644 > > --- a/hw/ppc/spapr_cpu_core.c > > +++ b/hw/ppc/spapr_cpu_core.c > > @@ -293,8 +293,15 @@ static void spapr_cpu_core_realize(DeviceState *dev, Error **errp) > > for (i = 0; i < cc->nr_threads; i++) { > > char id[32]; > > obj = sc->threads + i * size; > > + CPUState *cs; > > > > object_initialize(obj, size, typename); > > + cs = CPU(obj); > > + > > + /* Use core_id (which is actually cpu_dt_id) as stable CPU id */ > > + if (cs->has_stable_cpu_id) { > > + cs->stable_cpu_id = cc->core_id + i; > > + } > > Testing cs->has_stable_cpu_id here in machine type specific code seems > really weird. It's the machine type that knows whether it has a > stable ID to give to the CPU or not, rather than the other way around. > > Since we haven't yet had a release with cpu cores, I think the right > thing is for cpu_core to unconditionally set the stable ID (and set > has_stable_id to true). Right, we can set cpu_stable_id unconditionally here since this code path (core realize) will be taken only for pseries-2.7 onwards. has_stable_id will get set as part of the property we defined in SPAPR_COMPAT_2_7. > The backup path that does thread-based cpu > init, can set has_stable_id to false (if that's not the default). Default is off, but turning it on for 2.7 will be inherited by 2.6 and others below. Hence I have code to explicitly disable this prop for 2.6 and below via SPAPR_COMPAT_2_6. Regards, Bharata.