perf report: Report number of events, not samples

Number of samples is meaningless after we switched to auto-freq, so
report the number of events, i.e. not the sum of the different periods,
but the number PERF_RECORD_SAMPLE emitted by the kernel.

While doing this I noticed that naming "count" to the sum of all the
event periods can be confusing, so rename it to .period, just like in
struct sample.data, so that we become more consistent.

This helps with the next step, that was to record in struct hist_entry
the number of sample events for each instance, we need that because we
use it to generate the number of events when applying filters to the
tree of hist entries like it is being done in the TUI report browser.

Suggested-by: Ingo Molnar <mingo@elte.hu>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 22 insertions, 10 deletions

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index b8f47ded6287..68265120ee07 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -188,14 +188,14 @@ static int process_sample_event(event_t *event, struct perf_session *session)
 		return 0;
 
 	if (perf_session__add_hist_entry(session, &al, &data)) {
-		pr_debug("problem incrementing symbol count, skipping event\n");
+		pr_debug("problem incrementing symbol period, skipping event\n");
 		return -1;
 	}
 
 	attr = perf_header__find_attr(data.id, &session->header);
 
 	if (add_event_total(session, &data, attr)) {
-		pr_debug("problem adding event count\n");
+		pr_debug("problem adding event period\n");
 		return -1;
 	}
 
@@ -269,11 +269,25 @@ static struct perf_event_ops event_ops = {
 
 extern volatile int session_done;
 
-static void sig_handler(int sig __attribute__((__unused__)))
+static void sig_handler(int sig __used)
 {
 	session_done = 1;
 }
 
+static size_t hists__fprintf_nr_sample_events(struct hists *self,
+					      const char *evname, FILE *fp)
+{
+	size_t ret;
+	char unit;
+	unsigned long nr_events = self->stats.nr_events[PERF_RECORD_SAMPLE];
+
+	nr_events = convert_unit(nr_events, &unit);
+	ret = fprintf(fp, "# Events: %lu%c", nr_events, unit);
+	if (evname != NULL)
+		ret += fprintf(fp, " %s", evname);
+	return ret + fprintf(fp, "\n#\n");
+}
+
 static int __cmd_report(void)
 {
 	int ret = -EINVAL;
@@ -319,14 +333,12 @@ static int __cmd_report(void)
 		if (use_browser)
 			hists__browse(hists, help, input_name);
 		else {
-			if (rb_first(&session->hists.entries) ==
+			const char *evname = NULL;
+			if (rb_first(&session->hists.entries) !=
 			    rb_last(&session->hists.entries))
-				fprintf(stdout, "# Samples: %Ld\n#\n",
-					hists->stats.total_period);
-			else
-				fprintf(stdout, "# Samples: %Ld %s\n#\n",
-					hists->stats.total_period,
-					__event_name(hists->type, hists->config));
+				evname = __event_name(hists->type, hists->config);
+
+			hists__fprintf_nr_sample_events(hists, evname, stdout);
 
 			hists__fprintf(hists, NULL, false, stdout);
 			fprintf(stdout, "\n\n");