Commit 467b7d01 authored Feb 21, 2020 by Thara Gopinath Committed by Ingo Molnar Mar 06, 2020

sched/fair: Update cpu_capacity to reflect thermal pressure

cpu_capacity initially reflects the maximum possible capacity of a CPU.
Thermal pressure on a CPU means this maximum possible capacity is
unavailable due to thermal events. This patch subtracts the average
thermal pressure for a CPU from its maximum possible capacity so that
cpu_capacity reflects the remaining maximum capacity.

Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200222005213.3873-8-thara.gopinath@linaro.org

parent b4eccf5f

kernel/sched/fair.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -7984,8 +7984,15 @@ 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_avg 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(load).
		*/
		used = READ_ONCE(rq->avg_rt.util_avg);
		used += READ_ONCE(rq->avg_dl.util_avg);
		used += thermal_load_avg(rq);

		if (unlikely(used >= max))
		return 1;