Re: [PATCH v2 1/2] sched/schedutil: rework performance estimation

[Dietmar Eggemann <dietmar.eggemann@arm.com>]

On 26/10/2023 19:09, Vincent Guittot wrote:

[...]

> @@ -153,14 +152,38 @@ static unsigned int get_next_freq(struct sugov_policy *sg_policy,
>  	return cpufreq_driver_resolve_freq(policy, freq);
>  }
>  
> +unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
> +				 unsigned long min,
> +				 unsigned long max)
> +{
> +	unsigned long target;
> +	struct rq *rq = cpu_rq(cpu);
> +
> +	if (rt_rq_is_runnable(&rq->rt))
> +		return max;
> +
> +	/* Provide at least enough capacity for DL + IRQ */
> +	target = min;
> +
> +	actual = map_util_perf(actual);
> +	/* Actually we don't need to target the max performance */
> +	if (actual < max)
> +		max = actual;
> +
> +	/*
> +	 * Ensure at least minimum performance while providing more compute
> +	 * capacity when possible.
> +	 */
> +	return max(target, max);

The superfluous `unsigned long target` is still there?

  return max(min, max) is much cleaer.

[...]