Re: [PATCH 1/2] x86,sched: Add support for frequency invariance

[Quentin Perret]

Hi Giovanni

On Monday 09 Sep 2019 at 04:42:15 (+0200), Giovanni Gherdovich wrote:
> +static inline long arch_scale_freq_capacity(int cpu)
> +{
> +     if (static_cpu_has(X86_FEATURE_APERFMPERF))
> +             return per_cpu(arch_cpu_freq, cpu);

So, if this is conditional, perhaps you could also add this check in an
x86-specific implementation of arch_scale_freq_invariant() ? That would
guide sugov in the right path (see get_next_freq()) if APERF/MPERF are
unavailable.

> +     return 1024 /* SCHED_CAPACITY_SCALE */;
> +}

Thanks,
Quentin