Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753832AbaGJNmd (ORCPT ); Thu, 10 Jul 2014 09:42:33 -0400 Received: from mail-oa0-f43.google.com ([209.85.219.43]:44823 "EHLO mail-oa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753281AbaGJNmc (ORCPT ); Thu, 10 Jul 2014 09:42:32 -0400 MIME-Version: 1.0 In-Reply-To: <20140709105721.GT19379@twins.programming.kicks-ass.net> References: <1404144343-18720-1-git-send-email-vincent.guittot@linaro.org> <1404144343-18720-5-git-send-email-vincent.guittot@linaro.org> <20140709105721.GT19379@twins.programming.kicks-ass.net> From: Vincent Guittot Date: Thu, 10 Jul 2014 15:42:11 +0200 Message-ID: Subject: Re: [PATCH v3 04/12] sched: Allow all archs to set the power_orig To: Peter Zijlstra Cc: Ingo Molnar , linux-kernel , Russell King - ARM Linux , LAK , Preeti U Murthy , Morten Rasmussen , Mike Galbraith , Nicolas Pitre , "linaro-kernel@lists.linaro.org" , Daniel Lezcano , Dietmar Eggemann 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 On 9 July 2014 12:57, Peter Zijlstra wrote: > On Mon, Jun 30, 2014 at 06:05:35PM +0200, Vincent Guittot wrote: >> power_orig is only changed for system with a SMT sched_domain level in order to >> reflect the lower capacity of CPUs. Heterogenous system also have to reflect an >> original capacity that is different from the default value. >> >> Create a more generic function arch_scale_cpu_power that can be also used by >> non SMT platform to set power_orig. >> >> The weak behavior of arch_scale_cpu_power is the previous SMT one in order to >> keep backward compatibility in the use of power_orig. >> >> Signed-off-by: Vincent Guittot >> --- >> kernel/sched/fair.c | 24 ++++++++++++++++-------- >> 1 file changed, 16 insertions(+), 8 deletions(-) >> >> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c >> index 148b277..f0bba5f 100644 >> --- a/kernel/sched/fair.c >> +++ b/kernel/sched/fair.c >> @@ -5614,6 +5614,20 @@ unsigned long __weak arch_scale_smt_capacity(struct sched_domain *sd, int cpu) >> return default_scale_smt_capacity(sd, cpu); >> } >> >> +unsigned long __weak arch_scale_cpu_capacity(struct sched_domain *sd, int cpu) >> +{ >> + unsigned long weight = sd->span_weight; >> + >> + if ((sd->flags & SD_SHARE_CPUCAPACITY) && weight > 1) { >> + if (sched_feat(ARCH_CAPACITY)) >> + return arch_scale_smt_capacity(sd, cpu); >> + else >> + return default_scale_smt_capacity(sd, cpu); >> + } >> + >> + return SCHED_CAPACITY_SCALE; >> +} > > The only caller of arch_scale_smt_capacity is now an arch_ function > itself; which makes it entirely redundant, no? > > Also, sched_feat() and default_scale_smt_capability() aren't available > to arch implementations of this function and can thus not retain > semantics. > > Seeing how we currently don't have any arch_scale_smt_capacity > implementations other than the default we can easily replace it entirely > with something like: > > unsigned long __weak arch_scale_cpu_capacity() > { > if ((sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1)) > return sd->smt_gain / sd->span_weight; > > return SCHED_CAPACITY_SCALE; > } > > Hmm? That's fair. i'm going to clean up and remove unused function -- 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/