Re: [PATCH v2 02/10] cpufreq: provide data for frequency-invariant load-tracking support

From: Dietmar Eggemann
Date: Tue Jul 11 2017 - 11:06:26 EST

On 11/07/17 07:01, Viresh Kumar wrote:
> On 10-07-17, 13:02, Dietmar Eggemann wrote:
>> Yes, I will change this. The #define approach is not really necessary
>> here since we're not in the scheduler hot-path and inlining is not
>> really required here.
> It would be part of scheduler hot-path for the fast-switching case, isn't it ?
> (I am not arguing against using weak functions, just wanted to correct above
> statement).

Yes you're right here.

But in the meantime we're convinced that cpufreq_driver_fast_switch() is
not the right place to call arch_set_freq_scale() since for (future)
arm/arm64 fast-switch driver, the return value of
cpufreq_driver->fast_switch() does not give us the information that the
frequency value did actually change.

So we probably have to do this soemwhere in the cpufreq driver(s) to
support fast-switching until we have aperf/mperf like counters.