From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steve Muckle Subject: [PATCH 1/2] sched: cpufreq: ignore SMT when determining max cpu capacity Date: Fri, 26 Aug 2016 11:40:47 -0700 Message-ID: <1472236848-17038-2-git-send-email-smuckle@linaro.org> References: <1472236848-17038-1-git-send-email-smuckle@linaro.org> Return-path: In-Reply-To: <1472236848-17038-1-git-send-email-smuckle@linaro.org> Sender: linux-kernel-owner@vger.kernel.org To: Peter Zijlstra , Ingo Molnar , "Rafael J . Wysocki" Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Vincent Guittot , Morten Rasmussen , Dietmar Eggemann , Juri Lelli , Patrick Bellasi , Steve Muckle List-Id: linux-pm@vger.kernel.org PELT does not consider SMT when scaling its utilization values via arch_scale_cpu_capacity(). The value in rq->cpu_capacity_orig does take SMT into consideration though and therefore may be smaller than the utilization reported by PELT. On an Intel i7-3630QM for example rq->cpu_capacity_orig is 589 but util_avg scales up to 1024. This means that a 50% utilized CPU will show up in schedutil as ~86% busy. Fix this by using the same CPU scaling value in schedutil as that which is used by PELT. Signed-off-by: Steve Muckle --- kernel/sched/cpufreq_schedutil.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index 60d985f4dc47..cb8a77b1ef1b 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -147,7 +147,9 @@ static unsigned int get_next_freq(struct sugov_cpu *sg_cpu, unsigned long util, static void sugov_get_util(unsigned long *util, unsigned long *max) { struct rq *rq = this_rq(); - unsigned long cfs_max = rq->cpu_capacity_orig; + unsigned long cfs_max; + + cfs_max = arch_scale_cpu_capacity(NULL, smp_processor_id()); *util = min(rq->cfs.avg.util_avg, cfs_max); *max = cfs_max; -- 2.7.3