From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933886AbaE3TZK (ORCPT ); Fri, 30 May 2014 15:25:10 -0400 Received: from mail-oa0-f45.google.com ([209.85.219.45]:37712 "EHLO mail-oa0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933084AbaE3TZI (ORCPT ); Fri, 30 May 2014 15:25:08 -0400 MIME-Version: 1.0 In-Reply-To: <53888719.70604@arm.com> References: <1400860385-14555-1-git-send-email-vincent.guittot@linaro.org> <1400860385-14555-11-git-send-email-vincent.guittot@linaro.org> <53888719.70604@arm.com> From: Vincent Guittot Date: Fri, 30 May 2014 21:24:48 +0200 Message-ID: Subject: Re: [PATCH v2 10/11] sched: move cfs task on a CPU with higher capacity To: Dietmar Eggemann Cc: "peterz@infradead.org" , "mingo@kernel.org" , "linux-kernel@vger.kernel.org" , "linux@arm.linux.org.uk" , "linux-arm-kernel@lists.infradead.org" , "preeti@linux.vnet.ibm.com" , Morten Rasmussen , "efault@gmx.de" , "nicolas.pitre@linaro.org" , "linaro-kernel@lists.linaro.org" , "daniel.lezcano@linaro.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 On 30 May 2014 15:26, Dietmar Eggemann wrote: > On 23/05/14 16:53, Vincent Guittot wrote: >> If the CPU is used for handling lot of IRQs, trig a load balance to check if >> it's worth moving its tasks on another CPU that has more capacity >> >> Signed-off-by: Vincent Guittot >> --- >> kernel/sched/fair.c | 13 +++++++++++++ >> 1 file changed, 13 insertions(+) >> >> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c >> index e8a30f9..2501e49 100644 >> --- a/kernel/sched/fair.c >> +++ b/kernel/sched/fair.c >> @@ -5948,6 +5948,13 @@ static bool update_sd_pick_busiest(struct lb_env *env, >> if (sgs->sum_nr_running > sgs->group_capacity) >> return true; >> >> + /* >> + * The group capacity is reduced probably because of activity from other > > Here 'group capacity' refers to sgs->group_power and not to > sgs->group_capacity, right? yes, you're right it's cpu_power, i will correct the comment > >> + * sched class or interrupts which use part of the available capacity >> + */ > > ... 'interrupts' only w/ CONFIG_IRQ_TIME_ACCOUNTING=y, right ? yes, we need CONFIG_IRQ_TIME_ACCOUNTING in order to scale the cpu_power with time spent under irq. I have made test with and without this config to show impact (in the cover letter) Thanks Vincent > >> + if ((sg->sgp->power_orig * 100) > (sgs->group_power * env->sd->imbalance_pct)) >> + return true; >> + > [...] > > > -- > 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/