Re: [Patch v4 4/6] sched/fair: update cpu_capcity to reflect thermal pressure

Qais Yousef
2019-10-23T12:29:06Z

On 10/22/19 16:34, Thara Gopinath wrote:
> 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 | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 4f9c2cb..be3e802 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -7727,6 +7727,7 @@ 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);

Maybe a naive question - but can we add util_avg with load_avg without
a conversion? I thought the 2 signals have different properties.

Cheers

--
Qais Yousef

>
> if (unlikely(used >= max))
> return 1;
> --
> 2.1.4
>