Re: [PATCH v2 3/3] cpufreq: intel_pstate: Update max frequency on global turbo changes

[Quentin Perret]

On Tuesday 05 Mar 2019 at 11:42:06 (+0100), Rafael J. Wysocki wrote:
> +static void intel_pstate_update_max_freq(unsigned int cpu)
> +{
> +	struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu);
> +	struct cpufreq_policy new_policy;
> +	struct cpudata *cpudata;
> +
> +	if (!policy)
> +		return;
> +
> +	cpudata = all_cpu_data[cpu];
> +	policy->cpuinfo.max_freq = global.turbo_disabled_mf ?
> +			cpudata->pstate.max_freq : cpudata->pstate.turbo_freq;

I'm not too familiar with how the Intel turbo stuff so bear with me but
is this 'pstate.turbo_freq' constant ?

Why not just write it unconditionally into cpuinfo.max_freq ? It's not
guaranteed to always be reachable anyways no ? So maybe that's OK to always
report that one regardless of the boost availability ?

> +	memcpy(&new_policy, policy, sizeof(*policy));
> +	new_policy.max = min(policy->user_policy.max, policy->cpuinfo.max_freq);
> +	new_policy.min = min(policy->user_policy.min, new_policy.max);
> +
> +	cpufreq_set_policy(policy, &new_policy);
> +
> +	cpufreq_cpu_release(policy);
> +}

Thanks,
Quentin