[PATCH v14 21/32] perf evsel: Don't pass evsel with sample

From: Ian Rogers

Date: Wed May 20 2026 - 15:50:02 EST


As struct perf_sample now directly contains its own resolved evsel pointer,
passing the evsel separately is redundant and clutters the interface.

Remove the redundant evsel parameter from evsel-specific handlers and
structures, ensuring the tool always directly accesses the evsel bound to the
sample. This simplifies the API signatures and eliminates the risk of passing
an inconsistent evsel.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/util/evsel.c | 61 +++++++++++++++++++++++++----------------
1 file changed, 37 insertions(+), 24 deletions(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index ee30e15af054..bb48568b8101 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -3003,52 +3003,62 @@ int evsel__open_per_thread(struct evsel *evsel, struct perf_thread_map *threads)
return ret;
}

-static int perf_evsel__parse_id_sample(const struct evsel *evsel,
- const union perf_event *event,
+static int perf_evsel__parse_id_sample(const union perf_event *event,
struct perf_sample *sample)
{
+ const struct evsel *evsel = sample->evsel;
u64 type = evsel->core.attr.sample_type;
const __u64 *array = event->sample.array;
bool swapped = evsel->needs_swap;
union u64_swap u;
-
- array += ((event->header.size -
- sizeof(event->header)) / sizeof(u64)) - 1;
+ int i = ((event->header.size - sizeof(event->header)) / sizeof(u64)) - 1;

if (type & PERF_SAMPLE_IDENTIFIER) {
- sample->id = *array;
- array--;
+ if (i < 0)
+ return -EFAULT;
+
+ sample->id = array[i--];
}

if (type & PERF_SAMPLE_CPU) {
- u.val64 = *array;
+ if (i < 0)
+ return -EFAULT;
+
+ u.val64 = array[i--];
if (swapped) {
/* undo swap of u64, then swap on individual u32s */
u.val64 = bswap_64(u.val64);
u.val32[0] = bswap_32(u.val32[0]);
}
-
sample->cpu = u.val32[0];
- array--;
}

if (type & PERF_SAMPLE_STREAM_ID) {
- sample->stream_id = *array;
- array--;
+ if (i < 0)
+ return -EFAULT;
+
+ sample->stream_id = array[i--];
}

if (type & PERF_SAMPLE_ID) {
- sample->id = *array;
- array--;
+ if (i < 0)
+ return -EFAULT;
+
+ sample->id = array[i--];
}

if (type & PERF_SAMPLE_TIME) {
- sample->time = *array;
- array--;
+ if (i < 0)
+ return -EFAULT;
+
+ sample->time = array[i--];
}

if (type & PERF_SAMPLE_TID) {
- u.val64 = *array;
+ if (i < 0)
+ return -EFAULT;
+
+ u.val64 = array[i--];
if (swapped) {
/* undo swap of u64, then swap on individual u32s */
u.val64 = bswap_64(u.val64);
@@ -3058,7 +3068,6 @@ static int perf_evsel__parse_id_sample(const struct evsel *evsel,

sample->pid = u.val32[0];
sample->tid = u.val32[1];
- array--;
}

return 0;
@@ -3244,15 +3253,18 @@ int evsel__parse_sample(struct evsel *evsel, union perf_event *event,

data->deferred_cookie = event->callchain_deferred.cookie;

- if (evsel->core.attr.sample_id_all)
- perf_evsel__parse_id_sample(evsel, event, data);
-
+ if (evsel->core.attr.sample_id_all) {
+ if (perf_evsel__parse_id_sample(event, data))
+ goto out_efault;
+ }
return 0;
}

if (event->header.type != PERF_RECORD_SAMPLE) {
- if (evsel->core.attr.sample_id_all)
- perf_evsel__parse_id_sample(evsel, event, data);
+ if (evsel->core.attr.sample_id_all) {
+ if (perf_evsel__parse_id_sample(event, data))
+ goto out_efault;
+ }
return 0;
}

@@ -3614,12 +3626,13 @@ int evsel__parse_sample_timestamp(struct evsel *evsel, union perf_event *event,

if (event->header.type != PERF_RECORD_SAMPLE) {
struct perf_sample data = {
+ .evsel = evsel,
.time = -1ULL,
};

if (!evsel->core.attr.sample_id_all)
return -1;
- if (perf_evsel__parse_id_sample(evsel, event, &data))
+ if (perf_evsel__parse_id_sample(event, &data))
return -1;

*timestamp = data.time;
--
2.54.0.746.g67dd491aae-goog