Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758023AbcCVAVT (ORCPT ); Mon, 21 Mar 2016 20:21:19 -0400 Received: from mail-pf0-f181.google.com ([209.85.192.181]:32989 "EHLO mail-pf0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753305AbcCVAVN (ORCPT ); Mon, 21 Mar 2016 20:21:13 -0400 From: Steve Muckle X-Google-Original-From: Steve Muckle To: Peter Zijlstra , Ingo Molnar Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, "Rafael J. Wysocki" , Vincent Guittot , Morten Rasmussen , Dietmar Eggemann , Juri Lelli , Patrick Bellasi , Michael Turquette Subject: [PATCH 2/2] sched/fair: do not call cpufreq hook unless util changed Date: Mon, 21 Mar 2016 17:21:08 -0700 Message-Id: <1458606068-7476-2-git-send-email-smuckle@linaro.org> X-Mailer: git-send-email 2.4.10 In-Reply-To: <1458606068-7476-1-git-send-email-smuckle@linaro.org> References: <1458606068-7476-1-git-send-email-smuckle@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1872 Lines: 57 There's no reason to call the cpufreq hook if the root cfs_rq utilization has not been modified. Signed-off-by: Steve Muckle --- kernel/sched/fair.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index d418deb04049..af58e826cffe 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2826,20 +2826,21 @@ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) { struct sched_avg *sa = &cfs_rq->avg; struct rq *rq = rq_of(cfs_rq); - int decayed, removed = 0; + int decayed, removed_load = 0, removed_util = 0; int cpu = cpu_of(rq); if (atomic_long_read(&cfs_rq->removed_load_avg)) { s64 r = atomic_long_xchg(&cfs_rq->removed_load_avg, 0); sa->load_avg = max_t(long, sa->load_avg - r, 0); sa->load_sum = max_t(s64, sa->load_sum - r * LOAD_AVG_MAX, 0); - removed = 1; + removed_load = 1; } if (atomic_long_read(&cfs_rq->removed_util_avg)) { long r = atomic_long_xchg(&cfs_rq->removed_util_avg, 0); sa->util_avg = max_t(long, sa->util_avg - r, 0); sa->util_sum = max_t(s32, sa->util_sum - r * LOAD_AVG_MAX, 0); + removed_util = 1; } decayed = __update_load_avg(now, cpu, sa, @@ -2850,7 +2851,8 @@ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) cfs_rq->load_last_update_time_copy = sa->last_update_time; #endif - if (cpu == smp_processor_id() && &rq->cfs == cfs_rq) { + if (cpu == smp_processor_id() && &rq->cfs == cfs_rq && + (decayed || removed_util)) { unsigned long max = rq->cpu_capacity_orig; /* @@ -2873,7 +2875,7 @@ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) min(sa->util_avg, max), max); } - return decayed || removed; + return decayed || removed_load; } /* Update task and its cfs_rq load average */ -- 2.4.10