[PATCH 06/35] perf tools: Add perf_event__synthesize_id_sample()

Adrian Hunter
2022-07-11T10:11:01Z

Add perf_event__synthesize_id_sample() to enable the synthesis of
ID samples.

This is needed by perf inject. When injecting events from a guest perf.data
file, there is a possibility that the sample ID numbers conflict. In that
case, perf_event__synthesize_id_sample() can be used to re-write the ID
sample.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
tools/perf/util/synthetic-events.c | 47 ++++++++++++++++++++++++++++++
tools/perf/util/synthetic-events.h | 1 +
2 files changed, 48 insertions(+)

diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c
index fe5db4bf0042..ed9623702f34 100644
--- a/tools/perf/util/synthetic-events.c
+++ b/tools/perf/util/synthetic-events.c
@@ -1712,6 +1712,53 @@ int perf_event__synthesize_sample(union perf_event *event, u64 type, u64 read_fo
return 0;
}

+int perf_event__synthesize_id_sample(__u64 *array, u64 type, const struct perf_sample *sample)
+{
+ __u64 *start = array;
+
+ /*
+ * used for cross-endian analysis. See git commit 65014ab3
+ * for why this goofiness is needed.
+ */
+ union u64_swap u;
+
+ if (type & PERF_SAMPLE_TID) {
+ u.val32[0] = sample->pid;
+ u.val32[1] = sample->tid;
+ *array = u.val64;
+ array++;
+ }
+
+ if (type & PERF_SAMPLE_TIME) {
+ *array = sample->time;
+ array++;
+ }
+
+ if (type & PERF_SAMPLE_ID) {
+ *array = sample->id;
+ array++;
+ }
+
+ if (type & PERF_SAMPLE_STREAM_ID) {
+ *array = sample->stream_id;
+ array++;
+ }
+
+ if (type & PERF_SAMPLE_CPU) {
+ u.val32[0] = sample->cpu;
+ u.val32[1] = 0;
+ *array = u.val64;
+ array++;
+ }
+
+ if (type & PERF_SAMPLE_IDENTIFIER) {
+ *array = sample->id;
+ array++;
+ }
+
+ return (void *)array - (void *)start;
+}
+
int perf_event__synthesize_id_index(struct perf_tool *tool, perf_event__handler_t process,
struct evlist *evlist, struct machine *machine)
{
diff --git a/tools/perf/util/synthetic-events.h b/tools/perf/util/synthetic-events.h
index 78a0450db164..b136ec3ec95d 100644
--- a/tools/perf/util/synthetic-events.h
+++ b/tools/perf/util/synthetic-events.h
@@ -55,6 +55,7 @@ int perf_event__synthesize_extra_attr(struct perf_tool *tool, struct evlist *evs
int perf_event__synthesize_extra_kmaps(struct perf_tool *tool, perf_event__handler_t process, struct machine *machine);
int perf_event__synthesize_features(struct perf_tool *tool, struct perf_session *session, struct evlist *evlist, perf_event__handler_t process);
int perf_event__synthesize_id_index(struct perf_tool *tool, perf_event__handler_t process, struct evlist *evlist, struct machine *machine);
+int perf_event__synthesize_id_sample(__u64 *array, u64 type, const struct perf_sample *sample);
int perf_event__synthesize_kernel_mmap(struct perf_tool *tool, perf_event__handler_t process, struct machine *machine);
int perf_event__synthesize_mmap_events(struct perf_tool *tool, union perf_event *event, pid_t pid, pid_t tgid, perf_event__handler_t process, struct machine *machine, bool mmap_data);
int perf_event__synthesize_modules(struct perf_tool *tool, perf_event__handler_t process, struct machine *machine);
--
2.25.1