[PATCH v1 2/4] perf test: stat output per thread of just the parent process

[Ian Rogers <irogers@google.com>]

Per-thread mode requires either system-wide (-a), a pid (-p) or a tid
(-t). The stat output tests were using system-wide mode but this is
racy when threads are starting and exiting - something that happens a
lot when running the tests in parallel (perf test -p). Avoid the race
conditions by using pid mode with the pid of the parent process.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/tests/shell/lib/stat_output.sh  | 2 +-
 tools/perf/tests/shell/stat+json_output.sh | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/tests/shell/lib/stat_output.sh b/tools/perf/tests/shell/lib/stat_output.sh
index c81d6a9f7983..9a176ceae4a3 100644
--- a/tools/perf/tests/shell/lib/stat_output.sh
+++ b/tools/perf/tests/shell/lib/stat_output.sh
@@ -79,7 +79,7 @@ check_per_thread()
 		echo "[Skip] paranoid and not root"
 		return
 	fi
-	perf stat --per-thread -a $2 true
+	perf stat --per-thread -p $$ $2 true
 	commachecker --per-thread
 	echo "[Success]"
 }
diff --git a/tools/perf/tests/shell/stat+json_output.sh b/tools/perf/tests/shell/stat+json_output.sh
index 2b9c6212dffc..6b630d33c328 100755
--- a/tools/perf/tests/shell/stat+json_output.sh
+++ b/tools/perf/tests/shell/stat+json_output.sh
@@ -105,7 +105,7 @@ check_per_thread()
 		echo "[Skip] paranoia and not root"
 		return
 	fi
-	perf stat -j --per-thread -a -o "${stat_output}" true
+	perf stat -j --per-thread -p $$ -o "${stat_output}" true
 	$PYTHON $pythonchecker --per-thread --file "${stat_output}"
 	echo "[Success]"
 }
-- 
2.44.0.278.ge034bb2e1d-goog