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| author | Hubert Chrzaniuk <hubert.chrzaniuk@intel.com> | 2015-09-14 13:31:00 +0200 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2015-09-26 00:50:54 -0400 |
| commit | b2b34dfe4d9aa4c468fc363b3b666974783ed1f9 (patch) | |
| tree | 1613d67821a25330cee5cdb348c41675f0cb177d /tools/power | |
| parent | 756357b8e4b072fd5ee86421f794e071a348802b (diff) | |
| download | lwn-b2b34dfe4d9aa4c468fc363b3b666974783ed1f9.tar.gz lwn-b2b34dfe4d9aa4c468fc363b3b666974783ed1f9.zip | |
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>
Diffstat (limited to 'tools/power')
| -rw-r--r-- | tools/power/x86/turbostat/turbostat.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c index e05d30336613..d333c819fa1f 100644 --- a/tools/power/x86/turbostat/turbostat.c +++ b/tools/power/x86/turbostat/turbostat.c @@ -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); |