Messages in this thread Patch in this message | | | From | Namhyung Kim <> | Subject | [PATCH] perf stat: Fix event grouping on forked task | Date | Tue, 14 Feb 2012 10:20:32 +0900 |
| |
When event group is enabled for forked task (i.e. no target task was specified) all events were disabled and marked ->enable_on_exec. However they are not counted at all since only group leader will be enabled on exec actually. So the result looked like below:
$ ./perf stat --group -- sleep 1
Performance counter stats for 'sleep 1':
0.554926 task-clock # 0.001 CPUs utilized <not counted> context-switches <not counted> CPU-migrations <not counted> page-faults <not counted> cycles <not supported> stalled-cycles-frontend <not supported> stalled-cycles-backend <not counted> instructions <not counted> branches <not counted> branch-misses
1.001228093 seconds time elapsed
Fix it by disabling group leader only.
Signed-off-by: Namhyung Kim <namhyung.kim@lge.com> --- tools/perf/builtin-stat.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-)
diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c index d14b37ad7638..b2fa61e539c0 100644 --- a/tools/perf/builtin-stat.c +++ b/tools/perf/builtin-stat.c @@ -296,7 +296,8 @@ static int create_perf_stat_counter(struct perf_evsel *evsel, if (system_wide) return perf_evsel__open_per_cpu(evsel, evsel_list->cpus, group, group_fd); - if (target_pid == -1 && target_tid == -1) { + if (target_pid == -1 && target_tid == -1 && + (!group || evsel == first)) { attr->disabled = 1; attr->enable_on_exec = 1; } -- 1.7.9
| |