[PATCH v3 1/2] perf script: Print comm, fork and exit events also

From: Namhyung Kim
Date: Tue Nov 26 2013 - 03:51:36 EST


If --show-task-events option is given, also print internal COMM, FORK
and EXIT events. It would be helpful for debugging.

$ perf script --show-task-events
...
swapper 0 [009] 3350640.335261: sched:sched_switch: prev_comm=swapper/9
sleep 9486 [009] 3350640.335509: PERF_RECORD_COMM: sleep:9486
sleep 9486 [009] 3350640.335806: sched:sched_stat_runtime: comm=sleep pid=9486
firefox 2635 [003] 3350641.275896: PERF_RECORD_FORK(2635:9487):(2635:2635)
firefox 2635 [003] 3350641.275896: sched:sched_process_fork: comm=firefox pid=2635
sleep 9486 [009] 3350641.336009: PERF_RECORD_EXIT(9486:9486):(9486:9486)

Suggested-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Reviewed-by: David Ahern <dsahern@xxxxxxxxx>
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/Documentation/perf-script.txt | 3 +
tools/perf/builtin-script.c | 105 +++++++++++++++++++++++++++++++
2 files changed, 108 insertions(+)

diff --git a/tools/perf/Documentation/perf-script.txt b/tools/perf/Documentation/perf-script.txt
index e9cbfcddfa3f..67af9b77ea78 100644
--- a/tools/perf/Documentation/perf-script.txt
+++ b/tools/perf/Documentation/perf-script.txt
@@ -203,6 +203,9 @@ OPTIONS
--show-kernel-path::
Try to resolve the path of [kernel.kallsyms]

+--show-task-events
+ Display task related events (e.g. FORK, COMM, EXIT).
+
SEE ALSO
--------
linkperf:perf-record[1], linkperf:perf-script-perl[1],
diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 9f3ba4404a14..e2b9aff6506e 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -572,6 +572,7 @@ static int process_sample_event(struct perf_tool *tool __maybe_unused,
struct perf_script {
struct perf_tool tool;
struct perf_session *session;
+ bool show_task_events;
};

static int process_attr(struct perf_tool *tool, union perf_event *event,
@@ -602,6 +603,101 @@ static int process_attr(struct perf_tool *tool, union perf_event *event,
return perf_evsel__check_attr(evsel, scr->session);
}

+static int process_comm_event(struct perf_tool *tool,
+ union perf_event *event,
+ struct perf_sample *sample,
+ struct machine *machine)
+{
+ struct thread *thread;
+ struct perf_script *script = container_of(tool, struct perf_script, tool);
+ struct perf_session *session = script->session;
+ struct perf_evsel *evsel = perf_evlist__first(session->evlist);
+ int ret = -1;
+
+ thread = machine__findnew_thread(machine, event->comm.pid, event->comm.tid);
+ if (thread == NULL) {
+ pr_debug("problem processing COMM event, skipping it.\n");
+ return -1;
+ }
+
+ if (perf_event__process_comm(tool, event, sample, machine) < 0)
+ goto out;
+
+ if (!evsel->attr.sample_id_all) {
+ sample->cpu = 0;
+ sample->time = 0;
+ sample->tid = event->comm.tid;
+ sample->pid = event->comm.pid;
+ }
+ print_sample_start(sample, thread, evsel);
+ perf_event__fprintf(event, stdout);
+ ret = 0;
+
+out:
+ return ret;
+}
+
+static int process_fork_event(struct perf_tool *tool,
+ union perf_event *event,
+ struct perf_sample *sample,
+ struct machine *machine)
+{
+ struct thread *thread;
+ struct perf_script *script = container_of(tool, struct perf_script, tool);
+ struct perf_session *session = script->session;
+ struct perf_evsel *evsel = perf_evlist__first(session->evlist);
+
+ if (perf_event__process_fork(tool, event, sample, machine) < 0)
+ return -1;
+
+ thread = machine__findnew_thread(machine, event->fork.pid, event->fork.tid);
+ if (thread == NULL) {
+ pr_debug("problem processing FORK event, skipping it.\n");
+ return -1;
+ }
+
+ if (!evsel->attr.sample_id_all) {
+ sample->cpu = 0;
+ sample->time = event->fork.time;
+ sample->tid = event->fork.tid;
+ sample->pid = event->fork.pid;
+ }
+ print_sample_start(sample, thread, evsel);
+ perf_event__fprintf(event, stdout);
+
+ return 0;
+}
+static int process_exit_event(struct perf_tool *tool,
+ union perf_event *event,
+ struct perf_sample *sample,
+ struct machine *machine)
+{
+ struct thread *thread;
+ struct perf_script *script = container_of(tool, struct perf_script, tool);
+ struct perf_session *session = script->session;
+ struct perf_evsel *evsel = perf_evlist__first(session->evlist);
+
+ thread = machine__findnew_thread(machine, event->fork.pid, event->fork.tid);
+ if (thread == NULL) {
+ pr_debug("problem processing EXIT event, skipping it.\n");
+ return -1;
+ }
+
+ if (!evsel->attr.sample_id_all) {
+ sample->cpu = 0;
+ sample->time = 0;
+ sample->tid = event->comm.tid;
+ sample->pid = event->comm.pid;
+ }
+ print_sample_start(sample, thread, evsel);
+ perf_event__fprintf(event, stdout);
+
+ if (perf_event__process_exit(tool, event, sample, machine) < 0)
+ return -1;
+
+ return 0;
+}
+
static void sig_handler(int sig __maybe_unused)
{
session_done = 1;
@@ -613,6 +709,13 @@ static int __cmd_script(struct perf_script *script)

signal(SIGINT, sig_handler);

+ /* override event processing functions */
+ if (script->show_task_events) {
+ script->tool.comm = process_comm_event;
+ script->tool.fork = process_fork_event;
+ script->tool.exit = process_exit_event;
+ }
+
ret = perf_session__process_events(script->session, &script->tool);

if (debug_mode)
@@ -1375,6 +1478,8 @@ int cmd_script(int argc, const char **argv, const char *prefix __maybe_unused)
"display extended information from perf.data file"),
OPT_BOOLEAN('\0', "show-kernel-path", &symbol_conf.show_kernel_path,
"Show the path of [kernel.kallsyms]"),
+ OPT_BOOLEAN('\0', "show-task-events", &script.show_task_events,
+ "Show the fork/comm/exit events"),
OPT_END()
};
const char * const script_usage[] = {
--
1.7.11.7

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/