tools/power turbostat: KNL workaround for %Busy and Avg_MHz
KNL increments APERF and MPERF every 1024 clocks. This is compliant with the architecture specification, which requires that only the ratio of APERF/MPERF need be valid. However, turbostat takes advantage of the fact that these two MSRs increment every un-halted clock at the actual and base frequency: AVG_MHz = APERF_delta/measurement_interval %Busy = MPERF_delta/TSC_delta This quirk is needed for these calculations to also work on KNL, which would otherwise show a value 1024x smaller than expected. Signed-off-by: Hubert Chrzaniuk <hubert.chrzaniuk@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
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