From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752734AbZH0Pnh (ORCPT ); Thu, 27 Aug 2009 11:43:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751997AbZH0Pnf (ORCPT ); Thu, 27 Aug 2009 11:43:35 -0400 Received: from tx2ehsobe001.messaging.microsoft.com ([65.55.88.11]:15298 "EHLO TX2EHSOBE001.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751436AbZH0Pne convert rfc822-to-8bit (ORCPT ); Thu, 27 Aug 2009 11:43:34 -0400 X-SpamScore: -1 X-BigFish: VPS-1(z34a4jz1432R98dN936eM10d1Ia594izz1202hzz3198u327alz32i6bh203h61h) X-Spam-TCS-SCL: 0:0 X-FB-SS: 5, X-WSS-ID: 0KP1L0A-01-8TY-02 X-M-MSG: Date: Thu, 27 Aug 2009 17:42:30 +0200 From: Andreas Herrmann To: Peter Zijlstra CC: Ingo Molnar , linux-kernel@vger.kernel.org Subject: Re: [PATCH 15/15] x86: Fix cpu_coregroup_mask to return correct cpumask on multi-node processors Message-ID: <20090827154230.GF13576@alberich.amd.com> References: <20090820131243.GO29327@alberich.amd.com> <20090820134604.GD29327@alberich.amd.com> <1251128176.7538.301.camel@twins> <20090825093101.GJ20811@alberich.amd.com> <1251194143.7538.1128.camel@twins> <20090825102409.GK20811@alberich.amd.com> <1251196502.7538.1136.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Disposition: inline In-Reply-To: <1251196502.7538.1136.camel@twins> User-Agent: Mutt/1.5.16 (2007-06-09) X-OriginalArrivalTime: 27 Aug 2009 15:42:30.0745 (UTC) FILETIME=[FCD6A490:01CA272C] Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 25, 2009 at 12:35:02PM +0200, Peter Zijlstra wrote: > On Tue, 2009-08-25 at 12:24 +0200, Andreas Herrmann wrote: > > On Tue, Aug 25, 2009 at 11:55:43AM +0200, Peter Zijlstra wrote: > > > On Tue, 2009-08-25 at 11:31 +0200, Andreas Herrmann wrote: > > > > On Mon, Aug 24, 2009 at 05:36:16PM +0200, Peter Zijlstra wrote: > > > > > On Thu, 2009-08-20 at 15:46 +0200, Andreas Herrmann wrote: > > > > > > The correct mask that describes core-siblings of an processor > > > > > > is topology_core_cpumask. See topology adapation patches, especially > > > > > > http://marc.info/?l=linux-kernel&m=124964999608179 > > > > > > > > > > > > > > > argh, violence, murder kill.. this is the worst possible hack and you're > > > > > extending it :/ > > > > > > > > So this is the third code area > > > > (besides sched_*_power_savings sysfs interface, and the __cpu_power fiddling) > > > > that is crap, mess, a hack. > > > > > > > > Didn't know that I'd enter such a minefield when touching this code. ;-( > > > > > > Yeah, you're lucky that way ;-) Its been creaking for a while, and I've > > > been making noises to the IBM people (who so far have been the main > > > source of power saving patches) to clean this up, but now you trod onto > > > all of it at once.. > > > > > > > What would be your perferred solution for the > > > > core_cpumask/llc_shared_map stuff? Another domain level to get rid of > > > > this function? > > > > > > Right, I'd like to see everything exposed as domain levels. > > > > > > > > > numa-cluster > > > numa > > > socket > > > in-socket-numa > > > multi-core > > > shared-cache > > > core > > > threads > > > > > > We currently have a fixed order of these things, but I think we should > > > simply provide helpers for building the sd tree and let the arch code do > > > that instead of exporting all these masks in a fixed order. > > > > > > Once we get the arch domain tree, we do degenerate stuff to cull all the > > > trivial domains and fold SD flags. > > > > So any in-socket-numa is only going to haeppen with the arch-defined > > domain tree. > > Well, we could see what it takes to make this work without that. I mean, > this is just how I'd like to see it end up, doesn't mean we cannot work > on it from multiple angles at the same time. Yup. > > Now that this is settled you should throw away the > > __build_sched_domains cleanup patches that are in tip. They won't be > > of use when domain creation code is basically changed. > > I'm not sure that's needed, we can continue work on refactoring that. > Small steps towards something better seems a better plan than a single > large step. Ok. Andreas -- Operating | Advanced Micro Devices GmbH System | Karl-Hammerschmidt-Str. 34, 85609 Dornach b. München, Germany Research | Geschäftsführer: Andrew Bowd, Thomas M. McCoy, Giuliano Meroni Center | Sitz: Dornach, Gemeinde Aschheim, Landkreis München (OSRC) | Registergericht München, HRB Nr. 43632