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    SubjectRe: [Patch v5 4/6] sched/fair: update cpu_capcity to reflect thermal pressure
    On Wed, Nov 6, 2019 at 12:20 AM Thara Gopinath
    <thara.gopinath@linaro.org> wrote:
    >
    > cpu_capacity relflects the maximum available capacity of a cpu. Thermal

    s/relflects/reflects

    > 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.
    >
    > Other signals that are deducted from cpu_capacity to reflect the actual
    > capacity available are rt and dl util_avg. util_avg tracks a binary signal
    > and uses the weights 1024 and 0. Whereas thermal pressure is tracked
    > using load_avg. load_avg uses the actual "delta" capacity as the weight.

    Consider rephrasing as,

    Currently, effective cpu capacity is calculated by deducting RT and DL
    average utilization (util_avg) from cpu_capacity. For thermal
    pressure, we use load_avg instead of util_avg which is a binary signal
    (0 or 1024) because <put why here>


    > Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
    > ---
    > kernel/sched/fair.c | 1 +
    > 1 file changed, 1 insertion(+)
    >
    > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
    > index 9fb0494..5f6c371 100644
    > --- a/kernel/sched/fair.c
    > +++ b/kernel/sched/fair.c
    > @@ -7738,6 +7738,7 @@ static unsigned long scale_rt_capacity(struct sched_domain *sd, int cpu)
    >
    > 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
    >

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