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From: kan.liang@linux.intel.com
To: acme@kernel.org,
	namhyung@kernel.org,
	irogers@google.com,
	jolsa@kernel.org,
	adrian.hunter@intel.com,
	linux-perf-users@vger.kernel.org,
	linux-kernel@vger.kernel.org
Cc: Kan Liang <kan.liang@linux.intel.com>,
	"Khalil, Amiri" <amiri.khalil@intel.com>,
	stable@vger.kernel.org
Subject: [PATCH V2] perf stat: Fix the hard-coded metrics calculation on the hybrid
Date: Thu,  6 Jun 2024 11:03:16 -0700
Message-Id: <20240606180316.4122904-1-kan.liang@linux.intel.com>
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From: Kan Liang <kan.liang@linux.intel.com>

The hard-coded metrics is wrongly calculated on the hybrid machine.

$ perf stat -e cycles,instructions -a sleep 1

 Performance counter stats for 'system wide':

        18,205,487      cpu_atom/cycles/
         9,733,603      cpu_core/cycles/
         9,423,111      cpu_atom/instructions/     #  0.52  insn per cycle
         4,268,965      cpu_core/instructions/     #  0.23  insn per cycle

The insn per cycle for cpu_core should be 4,268,965 / 9,733,603 = 0.44.

When finding the metric events, the find_stat() doesn't take the PMU
type into account. The cpu_atom/cycles/ is wrongly used to calculate
the IPC of the cpu_core.

In the hard-coded metrics, the events from a different PMU are only
SW_CPU_CLOCK and SW_TASK_CLOCK. They both have the stat type,
STAT_NSECS. Except the SW CLOCK events, check the PMU type as well.

Fixes: 0a57b910807a ("perf stat: Use counts rather than saved_value")
Reported-by: "Khalil, Amiri" <amiri.khalil@intel.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: stable@vger.kernel.org
---

Changes since V1:
- Don't check the PMU of the SW CLOCK events 

 tools/perf/util/stat-shadow.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
index 3466aa952442..6bb975e46de3 100644
--- a/tools/perf/util/stat-shadow.c
+++ b/tools/perf/util/stat-shadow.c
@@ -176,6 +176,13 @@ static double find_stat(const struct evsel *evsel, int aggr_idx, enum stat_type
 		if (type != evsel__stat_type(cur))
 			continue;
 
+		/*
+		 * Except the SW CLOCK events,
+		 * ignore if not the PMU we're looking for.
+		 */
+		if ((type != STAT_NSECS) && (evsel->pmu != cur->pmu))
+			continue;
+
 		aggr = &cur->stats->aggr[aggr_idx];
 		if (type == STAT_NSECS)
 			return aggr->counts.val;
-- 
2.35.1