diff options
author | Ian Rogers <irogers@google.com> | 2024-01-25 02:42:00 +0300 |
---|---|---|
committer | Sasha Levin <sashal@kernel.org> | 2024-03-27 01:17:01 +0300 |
commit | 7b3a278f29f28b36f71ca263b882e3120e12f881 (patch) | |
tree | 20116f34032e299d28df5494341146953532ce81 /tools/perf/util | |
parent | cf114d8d4a8d78df272116a745bb43b48cef65f4 (diff) | |
download | linux-7b3a278f29f28b36f71ca263b882e3120e12f881.tar.xz |
perf pmu: Treat the msr pmu as software
[ Upstream commit 24852ef2e2d5c555c2da05baff112ea414b6e0f5 ]
The msr PMU is a software one, meaning msr events may be grouped
with events in a hardware context. As the msr PMU isn't marked as a
software PMU by perf_pmu__is_software, groups with the msr PMU in
are broken and the msr events placed in a different group. This
may lead to multiplexing errors where a hardware event isn't
counted while the msr event, such as tsc, is. Fix all of this by
marking the msr PMU as software, which agrees with the driver.
Before:
```
$ perf stat -e '{slots,tsc}' -a true
WARNING: events were regrouped to match PMUs
Performance counter stats for 'system wide':
1,750,335 slots
4,243,557 tsc
0.001456717 seconds time elapsed
```
After:
```
$ perf stat -e '{slots,tsc}' -a true
Performance counter stats for 'system wide':
12,526,380 slots
3,415,163 tsc
0.001488360 seconds time elapsed
```
Fixes: 251aa040244a ("perf parse-events: Wildcard most "numeric" events")
Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Cc: James Clark <james.clark@arm.com>
Cc: Caleb Biggers <caleb.biggers@intel.com>
Cc: Edward Baker <edward.baker@intel.com>
Cc: Perry Taylor <perry.taylor@intel.com>
Cc: Samantha Alt <samantha.alt@intel.com>
Cc: Weilin Wang <weilin.wang@intel.com>
Link: https://lore.kernel.org/r/20240124234200.1510417-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'tools/perf/util')
-rw-r--r-- | tools/perf/util/pmu.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c index 3c9609944a2f..88b9aa7d3a27 100644 --- a/tools/perf/util/pmu.c +++ b/tools/perf/util/pmu.c @@ -1760,6 +1760,12 @@ bool pmu__name_match(const struct perf_pmu *pmu, const char *pmu_name) bool perf_pmu__is_software(const struct perf_pmu *pmu) { + const char *known_sw_pmus[] = { + "kprobe", + "msr", + "uprobe", + }; + if (pmu->is_core || pmu->is_uncore || pmu->auxtrace) return false; switch (pmu->type) { @@ -1771,7 +1777,11 @@ bool perf_pmu__is_software(const struct perf_pmu *pmu) case PERF_TYPE_BREAKPOINT: return true; default: break; } - return !strcmp(pmu->name, "kprobe") || !strcmp(pmu->name, "uprobe"); + for (size_t i = 0; i < ARRAY_SIZE(known_sw_pmus); i++) { + if (!strcmp(pmu->name, known_sw_pmus[i])) + return true; + } + return false; } FILE *perf_pmu__open_file(const struct perf_pmu *pmu, const char *name) |