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From:   Thara Gopinath <thara.gopinath@linaro.org>
To:     mingo@redhat.com, peterz@infradead.org, ionela.voinescu@arm.com,
        vincent.guittot@linaro.org, rui.zhang@intel.com,
        qperret@google.com, daniel.lezcano@linaro.org,
        viresh.kumar@linaro.org
Cc:     linux-kernel@vger.kernel.org, amit.kachhap@gmail.com,
        javi.merino@kernel.org, amit.kucheria@verdurent.com
Subject: [Patch v6 5/7] sched/fair: update cpu_capacity to reflect thermal pressure
Date:   Wed, 11 Dec 2019 23:11:46 -0500
Message-Id: <1576123908-12105-6-git-send-email-thara.gopinath@linaro.org>
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cpu_capacity relflects the maximum available capacity of a cpu. Thermal
pressure on a cpu means this maximum available capacity is reduced. This
patch reduces the average thermal pressure for a cpu from its maximum
available capacity so that cpu_capacity reflects the actual
available capacity.

Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
---
 kernel/sched/fair.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index e12a375..4840655 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -7725,8 +7725,15 @@ static unsigned long scale_rt_capacity(struct sched_domain *sd, int cpu)
 	if (unlikely(irq >= max))
 		return 1;
 
+	/*
+	 * avg_rt.util avg and avg_dl.util track binary signals
+	 * (running and not running) with weights 0 and 1024 respectively.
+	 * avg_thermal.load_avg tracks thermal pressure and the weighted
+	 * average uses the actual delta max capacity.
+	 */
 	used = READ_ONCE(rq->avg_rt.util_avg);
 	used += READ_ONCE(rq->avg_dl.util_avg);
+	used += READ_ONCE(rq->avg_thermal.load_avg);
 
 	if (unlikely(used >= max))
 		return 1;
-- 
2.1.4