Re: [PATCH 02/13] cpufreq: Add perf_freq to cpuinfo

[Jan Beulich <jbeulich@xxxxxxxx>]

On 03.05.2021 21:27, Jason Andryuk wrote:
> acpi-cpufreq scales the aperf/mperf measurements by max_freq, but HWP
> needs to scale by base frequency.  Settings max_freq to base_freq
> "works" but the code is not obvious, and returning values to userspace
> is tricky.  Add an additonal perf_freq member which is used for scaling
> aperf/mperf measurements.
> 
> Signed-off-by: Jason Andryuk <jandryuk@xxxxxxxxx>
> ---
> I don't like this, but it seems the best way to re-use the common
> aperf/mperf code.  The other option would be to add wrappers that then
> do the acpi vs. hwp scaling.

Not sure I understand what you mean by "wrappers". I would assume that
for hwp you simply install a different getavg hook? Or else I guess
I'd need to see at least an outline of what you see as the alternative.

Jan