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 [thread overview]
Message-ID: <20240606180316.4122904-1-kan.liang@linux.intel.com> (raw)
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
next reply other threads:[~2024-06-06 18:04 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-06-06 18:03 kan.liang [this message]
2024-06-07 18:27 ` [PATCH V2] perf stat: Fix the hard-coded metrics calculation on the hybrid Namhyung Kim
2024-06-24 17:49 ` Namhyung Kim
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20240606180316.4122904-1-kan.liang@linux.intel.com \
--to=kan.liang@linux.intel.com \
--cc=acme@kernel.org \
--cc=adrian.hunter@intel.com \
--cc=amiri.khalil@intel.com \
--cc=irogers@google.com \
--cc=jolsa@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-perf-users@vger.kernel.org \
--cc=namhyung@kernel.org \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox