Searched hist:"9 ab95b0b15a092abb7c3309f3580f572a041f9ab" (Results 1 – 3 of 3) sorted by relevance
/linux/tools/perf/arch/x86/util/ |
H A D | evsel.c | diff 9ab95b0b15a092abb7c3309f3580f572a041f9ab Sat Jun 04 06:45:12 CEST 2022 Ravi Bangoria <ravi.bangoria@amd.com> perf record ibs: Warn about sampling period skew
Samples without an L3 miss are discarded and counter is reset with random value (between 1-15 for fetch PMU and 1-127 for op PMU) when IBS L3 miss filtering is enabled. This causes a sampling period skew but there is no way to reconstruct aggregated sampling period. So print a warning at perf record if user sets l3missonly=1.
Ex:
# perf record -c 10000 -C 0 -e ibs_op/l3missonly=1/ WARNING: Hw internally resets sampling period when L3 Miss Filtering is enabled and tagged operation does not cause L3 Miss. This causes sampling period skew.
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com> Acked-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Ananth Narayan <ananth.narayan@amd.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kim Phillips <kim.phillips@amd.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Robert Richter <rrichter@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Santosh Shukla <santosh.shukla@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: like.xu.linux@gmail.com Cc: x86@kernel.org Link: http://lore.kernel.org/lkml/20220604044519.594-2-ravi.bangoria@amd.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
/linux/tools/perf/util/ |
H A D | evsel.h | diff 9ab95b0b15a092abb7c3309f3580f572a041f9ab Sat Jun 04 06:45:12 CEST 2022 Ravi Bangoria <ravi.bangoria@amd.com> perf record ibs: Warn about sampling period skew
Samples without an L3 miss are discarded and counter is reset with random value (between 1-15 for fetch PMU and 1-127 for op PMU) when IBS L3 miss filtering is enabled. This causes a sampling period skew but there is no way to reconstruct aggregated sampling period. So print a warning at perf record if user sets l3missonly=1.
Ex:
# perf record -c 10000 -C 0 -e ibs_op/l3missonly=1/ WARNING: Hw internally resets sampling period when L3 Miss Filtering is enabled and tagged operation does not cause L3 Miss. This causes sampling period skew.
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com> Acked-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Ananth Narayan <ananth.narayan@amd.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kim Phillips <kim.phillips@amd.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Robert Richter <rrichter@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Santosh Shukla <santosh.shukla@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: like.xu.linux@gmail.com Cc: x86@kernel.org Link: http://lore.kernel.org/lkml/20220604044519.594-2-ravi.bangoria@amd.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
H A D | evsel.c | diff 9ab95b0b15a092abb7c3309f3580f572a041f9ab Sat Jun 04 06:45:12 CEST 2022 Ravi Bangoria <ravi.bangoria@amd.com> perf record ibs: Warn about sampling period skew
Samples without an L3 miss are discarded and counter is reset with random value (between 1-15 for fetch PMU and 1-127 for op PMU) when IBS L3 miss filtering is enabled. This causes a sampling period skew but there is no way to reconstruct aggregated sampling period. So print a warning at perf record if user sets l3missonly=1.
Ex:
# perf record -c 10000 -C 0 -e ibs_op/l3missonly=1/ WARNING: Hw internally resets sampling period when L3 Miss Filtering is enabled and tagged operation does not cause L3 Miss. This causes sampling period skew.
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com> Acked-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Ananth Narayan <ananth.narayan@amd.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kim Phillips <kim.phillips@amd.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Robert Richter <rrichter@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Santosh Shukla <santosh.shukla@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: like.xu.linux@gmail.com Cc: x86@kernel.org Link: http://lore.kernel.org/lkml/20220604044519.594-2-ravi.bangoria@amd.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|