perf tools: Implement counter output multiplexing

Finish the -M/--multiplex option implementation:

 - separate it out from group_fd

 - correctly set it via the ioctl and dont mmap counters that
   are multiplexed

 - modify the perf record event loop to deal with buffer-less
   counters.

 - remove the -g option from perf sched record

 - account for unordered events in perf sched latency

 - (add -f to perf sched record to ease measurements)

 - skip idle threads (pid==0) in latency output

The result is better latency output by 'perf sched latency':

 -----------------------------------------------------------------------------------
  Task              |  Runtime ms | Switches | Average delay ms | Maximum delay ms |
 -----------------------------------------------------------------------------------
  ksoftirqd/8       |    0.071 ms |        2 | avg:    0.458 ms | max:    0.913 ms |
  at-spi-registry   |    0.609 ms |       19 | avg:    0.013 ms | max:    0.023 ms |
  perf              |    3.316 ms |       16 | avg:    0.013 ms | max:    0.054 ms |
  Xorg              |    0.392 ms |       19 | avg:    0.011 ms | max:    0.018 ms |
  sleep             |    0.537 ms |        2 | avg:    0.009 ms | max:    0.009 ms |
 -----------------------------------------------------------------------------------
  TOTAL:            |    4.925 ms |       58 |
 ---------------------------------------------

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: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 2 deletions

diff --git a/tools/perf/util/trace-event-parse.c b/tools/perf/util/trace-event-parse.c
index 64d6e302751..f6a8437141c 100644
--- a/tools/perf/util/trace-event-parse.c
+++ b/tools/perf/util/trace-event-parse.c
@@ -2722,8 +2722,10 @@ void print_event(int cpu, void *data, int size, unsigned long long nsecs,
 	type = trace_parse_common_type(data);
 
 	event = trace_find_event(type);
-	if (!event)
-		die("ug! no event found for type %d", type);
+	if (!event) {
+		printf("ug! no event found for type %d\n", type);
+		return;
+	}
 
 	pid = parse_common_pid(data);