[PATCH v5 1/7] topology: Add a new arch_scale_freq_reference

Sudeep Holla sudeep.holla at arm.com
Tue Nov 7 03:45:21 PST 2023


On Sat, Nov 04, 2023 at 11:59:01AM +0100, Vincent Guittot wrote:
> Create a new method to get a unique and fixed max frequency. Currently
> cpuinfo.max_freq or the highest (or last) state of performance domain are
> used as the max frequency when computing the frequency for a level of
> utilization but:
> - cpuinfo_max_freq can change at runtime. boost is one example of
>   such change.
> - cpuinfo.max_freq and last item of the PD can be different leading to
>   different results between cpufreq and energy model.
> 
> We need to save the reference frequency that has been used when computing
> the CPUs capacity and use this fixed and coherent value to convert between
> frequency and CPU's capacity.
> 
> In fact, we already save the frequency that has been used when computing
> the capacity of each CPU. We extend the precision to save kHz instead of
> MHz currently and we modify the type to be aligned with other variables
> used when converting frequency to capacity and the other way.
> 

For all the topology related changes here and patch 6/7 and 7/7:

Acked-by: Sudeep Holla <sudeep.holla at arm.com>

-- 
Regards,
Sudeep



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