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Date:   Thu, 2 Nov 2023 13:03:32 +0100
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Subject: Re: [PATCH v2 1/2] sched/schedutil: rework performance estimation
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To:     Vincent Guittot <vincent.guittot@linaro.org>, mingo@redhat.com,
        peterz@infradead.org, juri.lelli@redhat.com, rostedt@goodmis.org,
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        linux-pm@vger.kernel.org
Cc:     lukasz.luba@arm.com, wyes.karny@amd.com, beata.michalska@arm.com
References: <20231026170913.32605-1-vincent.guittot@linaro.org>
 <20231026170913.32605-2-vincent.guittot@linaro.org>
From:   Dietmar Eggemann <dietmar.eggemann@arm.com>
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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.

[...]