Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161753AbbBDScL (ORCPT ); Wed, 4 Feb 2015 13:32:11 -0500 Received: from foss-mx-na.foss.arm.com ([217.140.108.86]:41767 "EHLO foss-mx-na.foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S967073AbbBDScD (ORCPT ); Wed, 4 Feb 2015 13:32:03 -0500 From: Morten Rasmussen To: peterz@infradead.org, mingo@redhat.com Cc: vincent.guittot@linaro.org, dietmar.eggemann@arm.com, yuyang.du@intel.com, preeti@linux.vnet.ibm.com, mturquette@linaro.org, nico@linaro.org, rjw@rjwysocki.net, juri.lelli@arm.com, linux-kernel@vger.kernel.org Subject: [RFCv3 PATCH 46/48] sched: Turn off fast idling of cpus on a partially loaded system Date: Wed, 4 Feb 2015 18:31:23 +0000 Message-Id: <1423074685-6336-47-git-send-email-morten.rasmussen@arm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1423074685-6336-1-git-send-email-morten.rasmussen@arm.com> References: <1423074685-6336-1-git-send-email-morten.rasmussen@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1388 Lines: 38 From: Dietmar Eggemann We do not want to miss out on the ability to do energy-aware idle load balancing if the system is only partially loaded since the operational range of energy-aware scheduling corresponds to a partially loaded system. We might want to pull a single remaining task from a potential src cpu towards an idle destination cpu if the energy model tells us this is worth doing to save energy. cc: Ingo Molnar cc: Peter Zijlstra Signed-off-by: Dietmar Eggemann --- kernel/sched/fair.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index b6e2e92..92fd1d8 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -7734,7 +7734,7 @@ static int idle_balance(struct rq *this_rq) this_rq->idle_stamp = rq_clock(this_rq); if (this_rq->avg_idle < sysctl_sched_migration_cost || - !this_rq->rd->overload) { + (!energy_aware() && !this_rq->rd->overload)) { rcu_read_lock(); sd = rcu_dereference_check_sched_domain(this_rq->sd); if (sd) -- 1.9.1 -- 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/