Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754095Ab2FMN3f (ORCPT ); Wed, 13 Jun 2012 09:29:35 -0400 Received: from mail-pz0-f52.google.com ([209.85.210.52]:47669 "EHLO mail-pz0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753688Ab2FMN3c (ORCPT ); Wed, 13 Jun 2012 09:29:32 -0400 MIME-Version: 1.0 In-Reply-To: <1339591666.8980.26.camel@twins> References: <1339502524-10265-1-git-send-email-vincent.guittot@linaro.org> <1339502524-10265-4-git-send-email-vincent.guittot@linaro.org> <1339591666.8980.26.camel@twins> Date: Wed, 13 Jun 2012 15:29:31 +0200 Message-ID: Subject: Re: [RFC 3/4] ARM: topology: Update cpu_power according to DT information From: Vincent Guittot To: Peter Zijlstra Cc: Amit Kucheria , Jean Pihet , linux@arm.linux.org.uk, devicetree-discuss@lists.ozlabs.org, linux-kernel@vger.kernel.org, rob.herring@calxeda.com, linaro-dev@lists.linaro.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1444 Lines: 27 On 13 June 2012 14:47, Peter Zijlstra wrote: > On Wed, 2012-06-13 at 18:14 +0530, Amit Kucheria wrote: >> Various discussions around power-aware scheduling have amplified the >> need for the scheduler to have some knowledge of DVFS. This would then >> require the scheduler to track 'cpu_power' ( = max power) and perhaps >> a new variable 'current_power' that is changed by the DVFS framework. > > Note that capacity is in fact a better term -- not to be confused with > the capacity as currently in use within the load-balancer. Luckily > there's no way to read that an not be confused.. uhmm :-) >> >> The first goal, though, is to make sure that the scheduler can handle >> different cpu_power values due to asymmetric cores. > > I would think the very first goal was to do a simple packing balancer > before doing silly things with asymmetric setups.. but what do I know. In fact, there is 2 tracks, one for a power aware scheduler and one for setting the capacity of each core of a big.LITTLE system. This patch is for the latter and is not directly link to the power because the default/performance mode of the scheduler should also take advantage of this information -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/