Messages in this thread | | | Subject | Re: [PATCH v2 1/1] x86,sched: On AMD EPYC set freq_max = max_boost in schedutil invariant formula | From | Giovanni Gherdovich <> | Date | Wed, 03 Feb 2021 10:56:15 +0100 |
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On Tue, 2021-02-02 at 20:11 +0100, Rafael J. Wysocki wrote: > On Tue, Feb 2, 2021 at 7:45 PM Rafael J. Wysocki <rafael@kernel.org> wrote: > > > > On Tue, Jan 26, 2021 at 5:19 PM Giovanni Gherdovich <ggherdovich@suse.cz> wrote: > > > > > > > > > cpufreq core asks the driver what's the f_max. What's the answer? > > > > > > intel_pstate says: 1C > > > > Yes, unless turbo is disabled, in which case it is P0. > > BTW, and that actually is quite important, the max_freq reported by > intel_pstate doesn't matter for schedutil after the new ->adjust_perf > callback has been added, because that doesn't even use the frequency. > > So, as a long-term remedy, it may just be better to implement > ->adjust_perf in acpi_cpufreq().
Thanks for pointing this out.
I agree that in the long term adding ->adjust_perf to acpi_cpufreq is the best solution.
Yet for this submission, considering it's late in the 5.11 cycle, the patch I propose is a reasonable candidate: the footprint is small and it's gone through a fair amount of testing.
Thanks, Giovanni
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