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tools/power turbostat: KNL workaround for %Busy and Avg_MHz

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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>
This commit is contained in:
Hubert Chrzaniuk 2015-09-14 13:31:00 +02:00 committed by Len Brown
parent 756357b8e4
commit b2b34dfe4d
1 changed files with 13 additions and 0 deletions
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13
tools/power/x86/turbostat/turbostat.c
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@ -71,6 +71,7 @@ unsigned int extra_msr_offset32;
unsigned int extra_msr_offset64;
unsigned int extra_delta_offset32;
unsigned int extra_delta_offset64;
unsigned int aperf_mperf_multiplier = 1;
int do_smi;
double bclk;
unsigned int show_pkg;
@ -984,6 +985,8 @@ int get_counters(struct thread_data *t, struct core_data *c, struct pkg_data *p)
return -3;
if (get_msr(cpu, MSR_IA32_MPERF, &t->mperf))
return -4;
t->aperf = t->aperf * aperf_mperf_multiplier;
t->mperf = t->mperf * aperf_mperf_multiplier;
}
if (do_smi) {
@ -2541,6 +2544,13 @@ int is_knl(unsigned int family, unsigned int model)
return 0;
}
unsigned int get_aperf_mperf_multiplier(unsigned int family, unsigned int model)
{
if (is_knl(family, model))
return 1024;
return 1;
}
#define SLM_BCLK_FREQS 5
double slm_freq_table[SLM_BCLK_FREQS] = { 83.3, 100.0, 133.3, 116.7, 80.0};
@ -2742,6 +2752,9 @@ void process_cpuid()
}
}
if (has_aperf)
aperf_mperf_multiplier = get_aperf_mperf_multiplier(family, model);
do_nhm_platform_info = do_nhm_cstates = do_smi = probe_nhm_msrs(family, model);
do_snb_cstates = has_snb_msrs(family, model);
do_pc2 = do_snb_cstates && (pkg_cstate_limit >= PCL__2);