diff options
| -rw-r--r-- | tools/perf/builtin-record.c | 15 | ||||
| -rw-r--r-- | tools/perf/tests/attr/test-record-group | 1 | ||||
| -rw-r--r-- | tools/perf/tests/attr/test-record-group1 | 1 | ||||
| -rw-r--r-- | tools/perf/util/evsel.c | 42 |
4 files changed, 56 insertions, 3 deletions
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 371702785d6..268b356391f 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -701,7 +701,13 @@ static int __cmd_record(struct perf_record *rec, int argc, const char **argv) } } - perf_evlist__enable(evsel_list); + /* + * When perf is starting the traced process, all the events + * (apart from group members) have enable_on_exec=1 set, + * so don't spoil it by prematurely enabling them. + */ + if (!perf_target__none(&opts->target)) + perf_evlist__enable(evsel_list); /* * Let the child rip @@ -724,7 +730,12 @@ static int __cmd_record(struct perf_record *rec, int argc, const char **argv) waking++; } - if (done) + /* + * When perf is starting the traced process, at the end events + * die with the process and we wait for that. Thus no need to + * disable events in this case. + */ + if (done && !perf_target__none(&opts->target)) perf_evlist__disable(evsel_list); } diff --git a/tools/perf/tests/attr/test-record-group b/tools/perf/tests/attr/test-record-group index b945f770dc9..a6599e9a19d 100644 --- a/tools/perf/tests/attr/test-record-group +++ b/tools/perf/tests/attr/test-record-group @@ -15,3 +15,4 @@ sample_type=327 mmap=0 comm=0 enable_on_exec=0 +disabled=0 diff --git a/tools/perf/tests/attr/test-record-group1 b/tools/perf/tests/attr/test-record-group1 index 013572f2360..5a8359da38a 100644 --- a/tools/perf/tests/attr/test-record-group1 +++ b/tools/perf/tests/attr/test-record-group1 @@ -16,3 +16,4 @@ sample_type=327 mmap=0 comm=0 enable_on_exec=0 +disabled=0 diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 6d4a5f6ed75..fc4faaa7afb 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -404,13 +404,40 @@ const char *perf_evsel__name(struct perf_evsel *evsel) return evsel->name ?: "unknown"; } +/* + * The enable_on_exec/disabled value strategy: + * + * 1) For any type of traced program: + * - all independent events and group leaders are disabled + * - all group members are enabled + * + * Group members are ruled by group leaders. They need to + * be enabled, because the group scheduling relies on that. + * + * 2) For traced programs executed by perf: + * - all independent events and group leaders have + * enable_on_exec set + * - we don't specifically enable or disable any event during + * the record command + * + * Independent events and group leaders are initially disabled + * and get enabled by exec. Group members are ruled by group + * leaders as stated in 1). + * + * 3) For traced programs attached by perf (pid/tid): + * - we specifically enable or disable all events during + * the record command + * + * When attaching events to already running traced we + * enable/disable events specifically, as there's no + * initial traced exec call. + */ void perf_evsel__config(struct perf_evsel *evsel, struct perf_record_opts *opts) { struct perf_event_attr *attr = &evsel->attr; int track = !evsel->idx; /* only the first counter needs these */ - attr->disabled = 1; attr->sample_id_all = opts->sample_id_all_missing ? 0 : 1; attr->inherit = !opts->no_inherit; attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED | @@ -486,6 +513,19 @@ void perf_evsel__config(struct perf_evsel *evsel, attr->mmap = track; attr->comm = track; + /* + * XXX see the function comment above + * + * Disabling only independent events or group leaders, + * keeping group members enabled. + */ + if (!evsel->leader) + attr->disabled = 1; + + /* + * Setting enable_on_exec for independent events and + * group leaders for traced executed by perf. + */ if (perf_target__none(&opts->target) && (!evsel->leader)) attr->enable_on_exec = 1; } |