Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752993AbaBJKKI (ORCPT ); Mon, 10 Feb 2014 05:10:08 -0500 Received: from mail-oa0-f51.google.com ([209.85.219.51]:61321 "EHLO mail-oa0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752147AbaBJKEa (ORCPT ); Mon, 10 Feb 2014 05:04:30 -0500 MIME-Version: 1.0 In-Reply-To: <1391728237-4441-4-git-send-email-daniel.lezcano@linaro.org> References: <1391728237-4441-1-git-send-email-daniel.lezcano@linaro.org> <1391728237-4441-4-git-send-email-daniel.lezcano@linaro.org> Date: Mon, 10 Feb 2014 15:34:29 +0530 Message-ID: Subject: Re: [PATCH V2 3/3] sched: Move idle_stamp up to the core From: Preeti Murthy To: Daniel Lezcano Cc: Peter Zijlstra , mingo@kernel.org, alex.shi@linaro.org, LKML , Lists linaro-kernel , Preeti U Murthy 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 Hi Daniel, On Fri, Feb 7, 2014 at 4:40 AM, Daniel Lezcano wrote: > The idle_balance modifies the idle_stamp field of the rq, making this > information to be shared across core.c and fair.c. As we can know if the > cpu is going to idle or not with the previous patch, let's encapsulate the > idle_stamp information in core.c by moving it up to the caller. The > idle_balance function returns true in case a balancing occured and the cpu > won't be idle, false if no balance happened and the cpu is going idle. > > Cc: mingo@kernel.org > Cc: alex.shi@linaro.org > Cc: peterz@infradead.org > Signed-off-by: Daniel Lezcano > Signed-off-by: Peter Zijlstra > --- > kernel/sched/core.c | 13 +++++++++++-- > kernel/sched/fair.c | 14 ++++++-------- > kernel/sched/sched.h | 8 +------- > 3 files changed, 18 insertions(+), 17 deletions(-) > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 16b97dd..428ee4c 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -2704,8 +2704,17 @@ need_resched: > > pre_schedule(rq, prev); > > - if (unlikely(!rq->nr_running)) > - idle_balance(rq); > +#ifdef CONFIG_SMP > + if (unlikely(!rq->nr_running)) { > + /* > + * We must set idle_stamp _before_ calling idle_balance(), such > + * that we measure the duration of idle_balance() as idle time. Should not this be "such that we *do not* measure the duration of idle_balance() as idle time?" Thanks Regards Preeti U Murthy -- 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/