perf script: Skip aggregation for stat events

commit 2fe6575924612f1014a0539ab3053b106aded926 upstream.

The script command does not support aggregation modes by itself although
that can be achieved using post-processing scripts. Because of this, it
does not allocate memory for aggregated event values.

Upon running perf stat record, the aggregation mode is set in the perf
data file. If the mode is AGGR_GLOBAL, the aggregated event values are
accessed and this leads to a segmentation fault since these were never
allocated to begin with. Set the mode to AGGR_NONE explicitly to avoid
this.

E.g.

  $ perf stat record -e cycles true
  $ perf script

Before:
  Segmentation fault (core dumped)

After:
  CPU   THREAD             VAL             ENA             RUN            TIME EVENT
   -1   231919          162831          362069          362069          935289 cycles:u

Fixes: 8b76a3188b85724f ("perf stat: Remove unused perf_counts.aggr field")
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ananth Narayan <ananth.narayan@amd.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: stable@vger.kernel.org # v6.2+
Link: https://lore.kernel.org/r/83d6c6c05c54bf00c5a9df32ac160718efca0c7a.1683280603.git.sandipan.das@amd.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 6f085602b7bd3e96f2e51355a283b817d2d48a15..d8c174a71938391b839caf87d7bf6ac5eaf4158f 100644 (file)
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -3652,6 +3652,13 @@ static int process_stat_config_event(struct perf_session *session __maybe_unused
                                     union perf_event *event)
 {
        perf_event__read_stat_config(&stat_config, &event->stat_config);
+
+       /*
+        * Aggregation modes are not used since post-processing scripts are
+        * supposed to take care of such requirements
+        */
+       stat_config.aggr_mode = AGGR_NONE;
+
        return 0;
 }