[PATCHv2] perf tools: Force uncore events to system wide monitoring

[Jiri Olsa <jolsa@redhat.com>]

On Mon, Feb 27, 2017 at 10:44:13AM +0100, Borislav Petkov wrote:
> On Mon, Feb 27, 2017 at 10:28:59AM +0100, Jiri Olsa wrote:
> > would you mind testing new version?
> 
> Looks ok to me.
> 
> Thanks.

thanks a lot, full patch attached

jirka


---
Making system wide (-a) the default option if no target
was specified and one of following conditions is met:

  - there's no workload specified (current behaviour)
  - there is workload specified but all requested
    events are system wide events

Mixed events core/uncore with workload:
  $ perf stat -e 'uncore_cbox_0/clockticks/,cycles' sleep 1

   Performance counter stats for 'sleep 1':

     <not supported>      uncore_cbox_0/clockticks/
             980,489      cycles

         1.000897406 seconds time elapsed

Uncore event with workload:
  $ perf stat -e 'uncore_cbox_0/clockticks/' sleep 1

   Performance counter stats for 'system wide':

  281,473,897,192,670      uncore_cbox_0/clockticks/

         1.000833784 seconds time elapsed

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/n/tip-rh8kybg6xdadfrw6x6uj37i2@git.kernel.org
---
 tools/perf/builtin-stat.c      | 32 +++++++++++++++++++++++++++++---
 tools/perf/util/parse-events.c |  5 +++--
 2 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index f4f555a67e9b..1320352cda04 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -2350,6 +2350,34 @@ static int __cmd_report(int argc, const char **argv)
 	return 0;
 }
 
+static void setup_system_wide(int forks)
+{
+	/*
+	 * Make system wide (-a) the default target if
+	 * no target was specified and one of following
+	 * conditions is met:
+	 *
+	 *   - there's no workload specified
+	 *   - there is workload specified but all requested
+	 *     events are system wide events
+	 */
+	if (!target__none(&target))
+		return;
+
+	if (!forks)
+		target.system_wide = true;
+	else {
+		struct perf_evsel *counter;
+
+		evlist__for_each_entry(evsel_list, counter) {
+			if (!counter->system_wide)
+				return;
+		}
+
+		target.system_wide = true;
+	}
+}
+
 int cmd_stat(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	const char * const stat_usage[] = {
@@ -2456,9 +2484,7 @@ int cmd_stat(int argc, const char **argv, const char *prefix __maybe_unused)
 	} else if (big_num_opt == 0) /* User passed --no-big-num */
 		big_num = false;
 
-	/* Make system wide (-a) the default target. */
-	if (!argc && target__none(&target))
-		target.system_wide = true;
+	setup_system_wide(argc);
 
 	if (run_count < 0) {
 		pr_err("Run count must be a positive number\n");
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 67a8aebc67ab..54355d3caf09 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -316,8 +316,9 @@ __add_event(struct list_head *list, int *idx,
 		return NULL;
 
 	(*idx)++;
-	evsel->cpus     = cpu_map__get(cpus);
-	evsel->own_cpus = cpu_map__get(cpus);
+	evsel->cpus        = cpu_map__get(cpus);
+	evsel->own_cpus    = cpu_map__get(cpus);
+	evsel->system_wide = !!cpus;
 
 	if (name)
 		evsel->name = strdup(name);
-- 
2.7.4