[PATCH 4/5] perf record: Add finished init event

Adrian Hunter
2022-06-10T11:34:01Z

In preparation for recording sideband events in a virtual machine guest so
that they can be injected into a host perf.data file.

This is needed to enable injecting events after the initial synthesized
user events (that have an all zero id sample) but before regular events.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
tools/lib/perf/include/perf/event.h | 1 +
tools/perf/builtin-inject.c | 1 +
tools/perf/builtin-record.c | 27 +++++++++++++++++++++++++++
tools/perf/util/event.c | 1 +
tools/perf/util/session.c | 4 ++++
tools/perf/util/tool.h | 3 ++-
6 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/tools/lib/perf/include/perf/event.h b/tools/lib/perf/include/perf/event.h
index e7758707cadd..9f7ca070da87 100644
--- a/tools/lib/perf/include/perf/event.h
+++ b/tools/lib/perf/include/perf/event.h
@@ -389,6 +389,7 @@ enum perf_user_event_type { /* above any possible kernel type */
PERF_RECORD_TIME_CONV = 79,
PERF_RECORD_HEADER_FEATURE = 80,
PERF_RECORD_COMPRESSED = 81,
+ PERF_RECORD_FINISHED_INIT = 82,
PERF_RECORD_HEADER_MAX
};

diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c
index a75bf11585b5..42e2918fd1cc 100644
--- a/tools/perf/builtin-inject.c
+++ b/tools/perf/builtin-inject.c
@@ -1059,6 +1059,7 @@ int cmd_inject(int argc, const char **argv)
.stat = perf_event__repipe_op2_synth,
.stat_round = perf_event__repipe_op2_synth,
.feature = perf_event__repipe_op2_synth,
+ .finished_init = perf_event__repipe_op2_synth,
.compressed = perf_event__repipe_op4_synth,
.auxtrace = perf_event__repipe_auxtrace,
},
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 40dca1fba4e3..cf5c5379ceaa 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1388,6 +1388,11 @@ static struct perf_event_header finished_round_event = {
.type = PERF_RECORD_FINISHED_ROUND,
};

+static struct perf_event_header finished_init_event = {
+ .size = sizeof(struct perf_event_header),
+ .type = PERF_RECORD_FINISHED_INIT,
+};
+
static void record__adjust_affinity(struct record *rec, struct mmap *map)
{
if (rec->opts.affinity != PERF_AFFINITY_SYS &&
@@ -1696,6 +1701,14 @@ static int record__synthesize_workload(struct record *rec, bool tail)
return err;
}

+static int write_finished_init(struct record *rec, bool tail)
+{
+ if (rec->opts.tail_synthesize != tail)
+ return 0;
+
+ return record__write(rec, NULL, &finished_init_event, sizeof(finished_init_event));
+}
+
static int record__synthesize(struct record *rec, bool tail);

static int
@@ -1710,6 +1723,8 @@ record__switch_output(struct record *rec, bool at_exit)

record__aio_mmap_read_sync(rec);

+ write_finished_init(rec, true);
+
record__synthesize(rec, true);
if (target__none(&rec->opts.target))
record__synthesize_workload(rec, true);
@@ -1764,6 +1779,7 @@ record__switch_output(struct record *rec, bool at_exit)
*/
if (target__none(&rec->opts.target))
record__synthesize_workload(rec, false);
+ write_finished_init(rec, false);
}
return fd;
}
@@ -2419,6 +2435,15 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
trigger_ready(&auxtrace_snapshot_trigger);
trigger_ready(&switch_output_trigger);
perf_hooks__invoke_record_start();
+
+ /*
+ * Must write FINISHED_INIT so it will be seen after all other
+ * synthesized user events, but before any regular events.
+ */
+ err = write_finished_init(rec, false);
+ if (err < 0)
+ goto out_child;
+
for (;;) {
unsigned long long hits = thread->samples;

@@ -2563,6 +2588,8 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n",
record__waking(rec));

+ write_finished_init(rec, true);
+
if (target__none(&rec->opts.target))
record__synthesize_workload(rec, true);

diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index 0476bb3a4188..1fa14598b916 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -76,6 +76,7 @@ static const char *perf_event__names[] = {
[PERF_RECORD_TIME_CONV] = "TIME_CONV",
[PERF_RECORD_HEADER_FEATURE] = "FEATURE",
[PERF_RECORD_COMPRESSED] = "COMPRESSED",
+ [PERF_RECORD_FINISHED_INIT] = "FINISHED_INIT",
};

const char *perf_event__name(unsigned int id)
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 0aa818977d2b..37f833c3c81b 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -562,6 +562,8 @@ void perf_tool__fill_defaults(struct perf_tool *tool)
tool->feature = process_event_op2_stub;
if (tool->compressed == NULL)
tool->compressed = perf_session__process_compressed_event;
+ if (tool->finished_init == NULL)
+ tool->finished_init = process_event_op2_stub;
}

static void swap_sample_id_all(union perf_event *event, void *data)
@@ -1706,6 +1708,8 @@ static s64 perf_session__process_user_event(struct perf_session *session,
if (err)
dump_event(session->evlist, event, file_offset, &sample, file_path);
return err;
+ case PERF_RECORD_FINISHED_INIT:
+ return tool->finished_init(session, event);
default:
return -EINVAL;
}
diff --git a/tools/perf/util/tool.h b/tools/perf/util/tool.h
index f2352dba1875..c957fb849ac6 100644
--- a/tools/perf/util/tool.h
+++ b/tools/perf/util/tool.h
@@ -76,7 +76,8 @@ struct perf_tool {
stat_config,
stat,
stat_round,
- feature;
+ feature,
+ finished_init;
event_op4 compressed;
event_op3 auxtrace;
bool ordered_events;
--
2.25.1