From: Kan Liang kan.liang@linux.intel.com
[ Upstream commit 39d5f412da84784bcc7f39ed49e55376be526fc7 ]
The patch ("perf evlist: Keep topdown counters in weak group") fixes the perf metrics topdown event issue when the topdown events are in a weak group on a non-hybrid platform. However, it doesn't work for the hybrid platform.
$./perf stat -e '{cpu_core/slots/,cpu_core/topdown-bad-spec/, cpu_core/topdown-be-bound/,cpu_core/topdown-fe-bound/, cpu_core/topdown-retiring/,cpu_core/branch-instructions/, cpu_core/branch-misses/,cpu_core/bus-cycles/,cpu_core/cache-misses/, cpu_core/cache-references/,cpu_core/cpu-cycles/,cpu_core/instructions/, cpu_core/mem-loads/,cpu_core/mem-stores/,cpu_core/ref-cycles/, cpu_core/cache-misses/,cpu_core/cache-references/}:W' -a sleep 1
Performance counter stats for 'system wide':
751,765,068 cpu_core/slots/ (84.07%) <not supported> cpu_core/topdown-bad-spec/ <not supported> cpu_core/topdown-be-bound/ <not supported> cpu_core/topdown-fe-bound/ <not supported> cpu_core/topdown-retiring/ 12,398,197 cpu_core/branch-instructions/ (84.07%) 1,054,218 cpu_core/branch-misses/ (84.24%) 539,764,637 cpu_core/bus-cycles/ (84.64%) 14,683 cpu_core/cache-misses/ (84.87%) 7,277,809 cpu_core/cache-references/ (77.30%) 222,299,439 cpu_core/cpu-cycles/ (77.28%) 63,661,714 cpu_core/instructions/ (84.85%) 0 cpu_core/mem-loads/ (77.29%) 12,271,725 cpu_core/mem-stores/ (77.30%) 542,241,102 cpu_core/ref-cycles/ (84.85%) 8,854 cpu_core/cache-misses/ (76.71%) 7,179,013 cpu_core/cache-references/ (76.31%)
1.003245250 seconds time elapsed
A hybrid platform has a different PMU name for the core PMUs, while the current perf hard code the PMU name "cpu".
The evsel->pmu_name can be used to replace the "cpu" to fix the issue. For a hybrid platform, the pmu_name must be non-NULL. Because there are at least two core PMUs. The PMU has to be specified. For a non-hybrid platform, the pmu_name may be NULL. Because there is only one core PMU, "cpu". For a NULL pmu_name, we can safely assume that it is a "cpu" PMU.
In case other PMUs also define the "slots" event, checking the PMU type as well.
With the patch,
$ perf stat -e '{cpu_core/slots/,cpu_core/topdown-bad-spec/, cpu_core/topdown-be-bound/,cpu_core/topdown-fe-bound/, cpu_core/topdown-retiring/,cpu_core/branch-instructions/, cpu_core/branch-misses/,cpu_core/bus-cycles/,cpu_core/cache-misses/, cpu_core/cache-references/,cpu_core/cpu-cycles/,cpu_core/instructions/, cpu_core/mem-loads/,cpu_core/mem-stores/,cpu_core/ref-cycles/, cpu_core/cache-misses/,cpu_core/cache-references/}:W' -a sleep 1
Performance counter stats for 'system wide':
766,620,266 cpu_core/slots/ (84.06%) 73,172,129 cpu_core/topdown-bad-spec/ # 9.5% bad speculation (84.06%) 193,443,341 cpu_core/topdown-be-bound/ # 25.0% backend bound (84.06%) 403,940,929 cpu_core/topdown-fe-bound/ # 52.3% frontend bound (84.06%) 102,070,237 cpu_core/topdown-retiring/ # 13.2% retiring (84.06%) 12,364,429 cpu_core/branch-instructions/ (84.03%) 1,080,124 cpu_core/branch-misses/ (84.24%) 564,120,383 cpu_core/bus-cycles/ (84.65%) 36,979 cpu_core/cache-misses/ (84.86%) 7,298,094 cpu_core/cache-references/ (77.30%) 227,174,372 cpu_core/cpu-cycles/ (77.31%) 63,886,523 cpu_core/instructions/ (84.87%) 0 cpu_core/mem-loads/ (77.31%) 12,208,782 cpu_core/mem-stores/ (77.31%) 566,409,738 cpu_core/ref-cycles/ (84.87%) 23,118 cpu_core/cache-misses/ (76.71%) 7,212,602 cpu_core/cache-references/ (76.29%)
1.003228667 seconds time elapsed
Signed-off-by: Kan Liang kan.liang@linux.intel.com Acked-by: Ian Rogers irogers@google.com Cc: Adrian Hunter adrian.hunter@intel.com Cc: Andi Kleen ak@linux.intel.com Cc: Ingo Molnar mingo@redhat.com Cc: Jiri Olsa jolsa@kernel.org Cc: Namhyung Kim namhyung@kernel.org Cc: Peter Zijlstra peterz@infradead.org Cc: Stephane Eranian eranian@google.com Cc: Xing Zhengjun zhengjun.xing@linux.intel.com Link: https://lore.kernel.org/r/20220518143900.1493980-2-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/arch/x86/util/evsel.c | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-)
diff --git a/tools/perf/arch/x86/util/evsel.c b/tools/perf/arch/x86/util/evsel.c index 0c9e56ab07b5..ff4561b7b600 100644 --- a/tools/perf/arch/x86/util/evsel.c +++ b/tools/perf/arch/x86/util/evsel.c @@ -31,10 +31,29 @@ void arch_evsel__fixup_new_cycles(struct perf_event_attr *attr) free(env.cpuid); }
+/* Check whether the evsel's PMU supports the perf metrics */ +static bool evsel__sys_has_perf_metrics(const struct evsel *evsel) +{ + const char *pmu_name = evsel->pmu_name ? evsel->pmu_name : "cpu"; + + /* + * The PERF_TYPE_RAW type is the core PMU type, e.g., "cpu" PMU + * on a non-hybrid machine, "cpu_core" PMU on a hybrid machine. + * The slots event is only available for the core PMU, which + * supports the perf metrics feature. + * Checking both the PERF_TYPE_RAW type and the slots event + * should be good enough to detect the perf metrics feature. + */ + if ((evsel->core.attr.type == PERF_TYPE_RAW) && + pmu_have_event(pmu_name, "slots")) + return true; + + return false; +} + bool arch_evsel__must_be_in_group(const struct evsel *evsel) { - if ((evsel->pmu_name && strcmp(evsel->pmu_name, "cpu")) || - !pmu_have_event("cpu", "slots")) + if (!evsel__sys_has_perf_metrics(evsel)) return false;
return evsel->name &&