Re: [PATCH] x86/tsc: Add tsc_tuned_baseclk flag disabling CPUID.16h use for tsc calibration
From: Andy Lutomirski <luto@amacapital.net>
Date: 2020-01-17 16:37:17
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On Jan 17, 2020, at 7:21 AM, Krzysztof Piecuch [off-list ref] wrote: Changing base clock frequency directly impacts tsc hz but not CPUID.16h values. An overclocked CPU supporting CPUID.16h and partial CPUID.15h support will set tsc hz according to "best guess" given by CPUID.16h relying on tsc_refine_calibration_work to give better numbers later. tsc_refine_calibration_work will refuse to do its work when the outcome is off the early tsc hz value by more than 1% which is certain to happen on an overclocked system.
Wouldn’t it be better to have an option tsc_max_refinement= to increase the 1%?