[PATCH v2 10/16] perf intel-tpebs: Add support for updating counts in evsel__tpebs_read

Ian Rogers
2025-04-07T05:01:28Z

Rename to reflect evsel argument and for consistency with other tpebs
functions. Update count from prev_raw_counts when
available. Eventually this will allow inteval mode support.

Signed-off-by: Ian Rogers <irogers@google.com>
---
tools/perf/util/evsel.c | 11 ++------
tools/perf/util/intel-tpebs.c | 52 ++++++++++++++---------------------
tools/perf/util/intel-tpebs.h | 2 +-
3 files changed, 25 insertions(+), 40 deletions(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 554252ed1aab..1d343f51225b 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1718,11 +1718,6 @@ static int evsel__read_one(struct evsel *evsel, int cpu_map_idx, int thread)
return perf_evsel__read(&evsel->core, cpu_map_idx, thread, count);
}

-static int evsel__read_retire_lat(struct evsel *evsel, int cpu_map_idx, int thread)
-{
- return tpebs_set_evsel(evsel, cpu_map_idx, thread);
-}
-
static void evsel__set_count(struct evsel *counter, int cpu_map_idx, int thread,
u64 val, u64 ena, u64 run, u64 lost)
{
@@ -1730,8 +1725,8 @@ static void evsel__set_count(struct evsel *counter, int cpu_map_idx, int thread,

count = perf_counts(counter->counts, cpu_map_idx, thread);

- if (counter->retire_lat) {
- evsel__read_retire_lat(counter, cpu_map_idx, thread);
+ if (evsel__is_retire_lat(counter)) {
+ evsel__tpebs_read(counter, cpu_map_idx, thread);
perf_counts__set_loaded(counter->counts, cpu_map_idx, thread, true);
return;
}
@@ -1889,7 +1884,7 @@ int evsel__read_counter(struct evsel *evsel, int cpu_map_idx, int thread)
return evsel__hwmon_pmu_read(evsel, cpu_map_idx, thread);

if (evsel__is_retire_lat(evsel))
- return evsel__read_retire_lat(evsel, cpu_map_idx, thread);
+ return evsel__tpebs_read(evsel, cpu_map_idx, thread);

if (evsel->core.attr.read_format & PERF_FORMAT_GROUP)
return evsel__read_group(evsel, cpu_map_idx, thread);
diff --git a/tools/perf/util/intel-tpebs.c b/tools/perf/util/intel-tpebs.c
index e3227646a9cc..452ce3698221 100644
--- a/tools/perf/util/intel-tpebs.c
+++ b/tools/perf/util/intel-tpebs.c
@@ -415,49 +415,39 @@ int evsel__tpebs_open(struct evsel *evsel)
return ret;
}

-
-int tpebs_set_evsel(struct evsel *evsel, int cpu_map_idx, int thread)
+int evsel__tpebs_read(struct evsel *evsel, int cpu_map_idx, int thread)
{
- __u64 val;
+ struct perf_counts_values *count, *old_count = NULL;
struct tpebs_retire_lat *t;
- struct perf_counts_values *count;
+ uint64_t val;
+
+ /* Only set retire_latency value to the first CPU and thread. */
+ if (cpu_map_idx != 0 || thread != 0)
+ return 0;
+
+ if (evsel->prev_raw_counts)
+ old_count = perf_counts(evsel->prev_raw_counts, cpu_map_idx, thread);

- /* Non reitre_latency evsel should never enter this function. */
- if (!evsel__is_retire_lat(evsel))
- return -1;
+ count = perf_counts(evsel->counts, cpu_map_idx, thread);

/*
* Need to stop the forked record to ensure get sampled data from the
* PIPE to process and get non-zero retire_lat value for hybrid.
*/
tpebs_stop();
- count = perf_counts(evsel->counts, cpu_map_idx, thread);

t = tpebs_retire_lat__find(evsel);
-
- /* Set ena and run to non-zero */
- count->ena = count->run = 1;
- count->lost = 0;
-
- if (!t) {
- /*
- * Set default value or 0 when retire_latency for this event is
- * not found from sampling data (record_tpebs not set or 0
- * sample recorded).
- */
- count->val = 0;
- return 0;
+ val = rint(t->val);
+
+ if (old_count) {
+ count->val = old_count->val + val;
+ count->run = old_count->run + 1;
+ count->ena = old_count->ena + 1;
+ } else {
+ count->val = val;
+ count->run++;
+ count->ena++;
}
-
- /*
- * Only set retire_latency value to the first CPU and thread.
- */
- if (cpu_map_idx == 0 && thread == 0)
- val = rint(t->val);
- else
- val = 0;
-
- count->val = val;
return 0;
}

diff --git a/tools/perf/util/intel-tpebs.h b/tools/perf/util/intel-tpebs.h
index 5c671181ec60..218a82866cee 100644
--- a/tools/perf/util/intel-tpebs.h
+++ b/tools/perf/util/intel-tpebs.h
@@ -12,6 +12,6 @@ extern bool tpebs_recording;

int evsel__tpebs_open(struct evsel *evsel);
void evsel__tpebs_close(struct evsel *evsel);
-int tpebs_set_evsel(struct evsel *evsel, int cpu_map_idx, int thread);
+int evsel__tpebs_read(struct evsel *evsel, int cpu_map_idx, int thread);

#endif /* __INTEL_TPEBS_H */
--
2.49.0.504.g3bcea36a83-goog