From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45804) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W1dBV-00072c-NO for qemu-devel@nongnu.org; Fri, 10 Jan 2014 09:35:47 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1W1dBQ-0000pw-Ct for qemu-devel@nongnu.org; Fri, 10 Jan 2014 09:35:41 -0500 Received: from mail-pd0-f176.google.com ([209.85.192.176]:61902) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W1dBP-0000pk-UI for qemu-devel@nongnu.org; Fri, 10 Jan 2014 09:35:36 -0500 Received: by mail-pd0-f176.google.com with SMTP id r10so680613pdi.35 for ; Fri, 10 Jan 2014 06:35:35 -0800 (PST) Message-ID: <52D00531.8030105@ozlabs.ru> Date: Sat, 11 Jan 2014 01:35:29 +1100 From: Alexey Kardashevskiy MIME-Version: 1.0 References: <1389245648-10300-1-git-send-email-aik@ozlabs.ru> <87ppo0na45.fsf@pixel.localdomain> <52CF1ECC.3040208@ozlabs.ru> <52CF4F37.4050306@ozlabs.ru> <878uuof0pu.fsf@pixel.localdomain> <84B5F34E-6072-4E56-8493-AAC69B9F7DAE@suse.de> <52CFF8B8.7010605@ozlabs.ru> <03847015-B363-4234-BF34-BB034D0BBE08@suse.de> <52D00002.7020208@ozlabs.ru> In-Reply-To: Content-Type: text/plain; charset=KOI8-R Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC PATCH v2] PPC: smp: autodetect numbers of threads per core List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexander Graf , Mike Day Cc: Paul Mackerras , "qemu-ppc@nongnu.org" , "qemu-devel@nongnu.org" On 01/11/2014 01:25 AM, Alexander Graf wrote: > > On 10.01.2014, at 15:21, Mike Day wrote: > >> On Fri, Jan 10, 2014 at 9:13 AM, Alexey Kardashevskiy >> wrote: >>> On 01/11/2014 01:00 AM, Alexander Graf wrote: >> >>>> Can't we determine the number of "default threads" at a common >>>> place, preferably derived from cpu type? >>> >>> We can do anything. I asked how exactly as I really (really) do not >>> understand the details. >>> >> >> Are you suggesting we create a dictionary with all the cpu type >> information stored in it (stepping, cores, threads, memory channels, >> caches) that we need to keep updated? > > We can always talk in extremes :). Today we have a dictionary of core > types in QEMU. If a certain core type comes with a specific number of > threads, that's a property of the core, no? No, the max smt number comes from cap_ppc_smt, not from CPU type. PR KVM may return something different (what does it return?) and TCG definitely will not allow anything but 1. Up to the accelerator, not a CPU class. -- Alexey