Commit dc02bf71 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

perf sched: Account for lost events, increase default buffering 



Output such lost event and state machine weirdness stats:

   TOTAL:                |  14974.910 ms |    46384 |
  ---------------------------------------------------
   INFO: 8.865% lost events (19132 out of 215819, in 8 chunks)
   INFO: 0.198% state machine bugs (49 out of 24708) (due to lost events?)

And increase buffering to -m 1024 (4 MB) by default. Since we
use output multiplexing that kind of space is needed.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 39aeb52f

tools/perf/builtin-sched.c

+41 −19
Original line number Diff line number Diff line
@@ -117,7 +117,11 @@ static u64 run_avg; 


static unsigned long		replay_repeat = 10;

static unsigned long		nr_timestamps;

static unsigned long		unordered_timestamps;

static unsigned long		nr_unordered_timestamps;

static unsigned long		nr_state_machine_bugs;

static unsigned long		nr_events;

static unsigned long		nr_lost_chunks;

static unsigned long		nr_lost_events;



#define TASK_STATE_TO_CHAR_STR "RSDTtZX"
@@ -668,14 +672,14 @@ process_comm_event(event_t *event, unsigned long offset, unsigned long head) 


	thread = threads__findnew(event->comm.pid, &threads, &last_match);



	dump_printf("%p [%p]: PERF_EVENT_COMM: %s:%d\n",

	dump_printf("%p [%p]: perf_event_comm: %s:%d\n",

		(void *)(offset + head),

		(void *)(long)(event->header.size),

		event->comm.comm, event->comm.pid);



	if (thread == NULL ||

	    thread__set_comm(thread, event->comm.comm)) {

		dump_printf("problem processing PERF_EVENT_COMM, skipping event.\n");

		dump_printf("problem processing perf_event_comm, skipping event.\n");

		return -1;

	}

	total_comm++;
@@ -1168,14 +1172,12 @@ latency_wakeup_event(struct trace_wakeup_event *wakeup_event, 


	atom = list_entry(atoms->work_list.prev, struct work_atom, list);



	if (atom->state != THREAD_SLEEPING) {

		printf("boo2\n");

		return;

	}

	if (atom->state != THREAD_SLEEPING)

		nr_state_machine_bugs++;



	nr_timestamps++;

	if (atom->sched_out_time > timestamp) {

		unordered_timestamps++;

		nr_unordered_timestamps++;

		return;

	}
@@ -1214,7 +1216,7 @@ static void output_lat_thread(struct work_atoms *work_list) 


	avg = work_list->total_lat / work_list->nb_atoms;



	printf("|%9.3f ms |%9llu | avg:%9.3f ms | max:%9.3f ms |\n",

	printf("|%11.3f ms |%9llu | avg:%9.3f ms | max:%9.3f ms |\n",

	      (double)work_list->total_runtime / 1e6,

		 work_list->nb_atoms, (double)avg / 1e6,

		 (double)work_list->max_lat / 1e6);
@@ -1359,9 +1361,9 @@ static void __cmd_lat(void) 
	read_events();

	sort_lat();



	printf("\n ---------------------------------------------------------------------------------------\n");

	printf("\n -----------------------------------------------------------------------------------------\n");

	printf("  Task                  |   Runtime ms  | Switches | Average delay ms | Maximum delay ms |\n");

	printf(" ---------------------------------------------------------------------------------------\n");

	printf(" -----------------------------------------------------------------------------------------\n");



	next = rb_first(&sorted_atom_root);
@@ -1373,18 +1375,32 @@ static void __cmd_lat(void) 
		next = rb_next(next);

	}



	printf(" ---------------------------------------------------------------------------------------\n");

	printf("  TOTAL:                |%9.3f ms |%9Ld |",

	printf(" -----------------------------------------------------------------------------------------\n");

	printf("  TOTAL:                |%11.3f ms |%9Ld |\n",

		(double)all_runtime/1e6, all_count);



	if (unordered_timestamps && nr_timestamps) {

		printf(" INFO: %.2f%% unordered events.\n",

			(double)unordered_timestamps/(double)nr_timestamps*100.0);

	printf(" ---------------------------------------------------\n");

	if (nr_unordered_timestamps && nr_timestamps) {

		printf("  INFO: %.3f%% unordered timestamps (%ld out of %ld)\n",

			(double)nr_unordered_timestamps/(double)nr_timestamps*100.0,

			nr_unordered_timestamps, nr_timestamps);

	} else {

	}

	if (nr_lost_events && nr_events) {

		printf("  INFO: %.3f%% lost events (%ld out of %ld, in %ld chunks)\n",

			(double)nr_lost_events/(double)nr_events*100.0,

			nr_lost_events, nr_events, nr_lost_chunks);

	}

	if (nr_state_machine_bugs && nr_timestamps) {

		printf("  INFO: %.3f%% state machine bugs (%ld out of %ld)",

			(double)nr_state_machine_bugs/(double)nr_timestamps*100.0,

			nr_state_machine_bugs, nr_timestamps);

		if (nr_lost_events)

			printf(" (due to lost events?)");

		printf("\n");

	}

	printf("\n");



	printf(" -------------------------------------------------\n\n");

}



static struct trace_sched_handler *trace_handler;
@@ -1585,8 +1601,13 @@ process_event(event_t *event, unsigned long offset, unsigned long head) 
{

	trace_event(event);



	nr_events++;

	switch (event->header.type) {

	case PERF_EVENT_MMAP ... PERF_EVENT_LOST:

	case PERF_EVENT_MMAP:

		return 0;

	case PERF_EVENT_LOST:

		nr_lost_chunks++;

		nr_lost_events += event->lost.lost;

		return 0;



	case PERF_EVENT_COMM:
@@ -1768,6 +1789,7 @@ static const char *record_args[] = { 
	"-R",

	"-M",

	"-f",

	"-m", "1024",

	"-c", "1",

	"-e", "sched:sched_switch:r",

	"-e", "sched:sched_stat_wait:r",

tools/perf/util/event.h

+1 −1

File changed.

Contains only whitespace changes.

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