[v2,2/4] tools/perf: Track where perf_sample_ids need per-thread periods
Commit Message
When PERF_SAMPLE_READ is used with inherit+inherit_stat the perf_sample_id is no longer
globally unique, but instead is unique per each inherited thread.
Track this fact in perf_sample_ids as it will be needed to correctly calculate the
period.
Signed-off-by: Ben Gainey <ben.gainey@arm.com>
---
tools/lib/perf/evlist.c | 1 +
tools/lib/perf/evsel.c | 7 +++++++
tools/lib/perf/include/internal/evsel.h | 7 +++++++
3 files changed, 15 insertions(+)
@@ -255,6 +255,7 @@ static void perf_evlist__id_hash(struct perf_evlist *evlist,
sid->id = id;
sid->evsel = evsel;
+ sid->period_per_thread = perf_evsel__attr_has_per_thread_sample_period(evsel);
hash = hash_64(sid->id, PERF_EVLIST__HLIST_BITS);
hlist_add_head(&sid->node, &evlist->heads[hash]);
}
@@ -537,6 +537,13 @@ void perf_evsel__free_id(struct perf_evsel *evsel)
evsel->ids = 0;
}
+bool perf_evsel__attr_has_per_thread_sample_period(struct perf_evsel *evsel)
+{
+ return (evsel->attr.sample_type & PERF_SAMPLE_READ)
+ && evsel->attr.inherit
+ && evsel->attr.inherit_stat;
+}
+
void perf_counts_values__scale(struct perf_counts_values *count,
bool scale, __s8 *pscaled)
{
@@ -36,6 +36,11 @@ struct perf_sample_id {
/* Holds total ID period value for PERF_SAMPLE_READ processing. */
u64 period;
+
+ /* When inherit+inherit_stat is combined with PERF_SAMPLE_READ, the
+ * period value is per (sample_id, thread) tuple, rather than per
+ * sample_id. */
+ bool period_per_thread;
};
struct perf_evsel {
@@ -88,4 +93,6 @@ int perf_evsel__apply_filter(struct perf_evsel *evsel, const char *filter);
int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads);
void perf_evsel__free_id(struct perf_evsel *evsel);
+bool perf_evsel__attr_has_per_thread_sample_period(struct perf_evsel *evsel);
+
#endif /* __LIBPERF_INTERNAL_EVSEL_H */