Messages in this thread | | | Date | Mon, 18 Jul 2022 13:26:22 -0400 | Subject | Re: [PATCH v4 0/3] Add arch TSC frequency information | From | "Liang, Kan" <> |
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On 2022-07-18 12:43 p.m., Ian Rogers wrote: > The first patch adds the #system_tsc_freq literal to expr.c and > computes it via cpuid. The second patches adds support for "older" > processors by computing the value via /proc/cpuinfo. The third patch > adds a test then the computation looks somewhat sensible. > > Such a literal is useful to calculate things like the average > frequency [1]. The TSC frequency isn't exposed by sysfs although some > experimental drivers look to add it [2]. > > [1] https://github.com/intel/perfmon-metrics/blob/5ad9ef7056f31075e8178b9f1fb732af183b2c8d/SKX/metrics/perf/skx_metric_perf.json#L11 > [2] https://github.com/trailofbits/tsc_freq_khz > > v4. Modified the patch order and separated out the test. > v3. Added the cpuid approach from Kan Liang. > v2. Adds warnings to make clear if things have changed/broken on future > Intel platforms. It also adds caching and an Intel specific that a > value is computed. > > Ian Rogers (2): > perf tsc: Add cpuinfo fall back for arch_get_tsc_freq > perf test: Add test for #system_tsc_freq in metrics
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Thanks, Kan
> > Kan Liang (1): > perf tsc: Add arch TSC frequency information > > tools/perf/arch/x86/util/cpuid.h | 34 ++++++++++++++ > tools/perf/arch/x86/util/header.c | 27 +++++------ > tools/perf/arch/x86/util/tsc.c | 77 +++++++++++++++++++++++++++++++ > tools/perf/tests/expr.c | 13 ++++++ > tools/perf/util/expr.c | 13 ++++++ > tools/perf/util/tsc.h | 1 + > 6 files changed, 149 insertions(+), 16 deletions(-) > create mode 100644 tools/perf/arch/x86/util/cpuid.h >
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