[PATCH 13/28] perf hists: Sort hist entries by accumulated period

[Namhyung Kim <namhyung@kernel.org>]

When callchain accumulation is requested, we need to sort the entries
by accumulated period value.  When accumulated periods of two entries
are same (i.e. single path callchain) put the caller above since
accumulation tends to put callers on higher position for obvious
reason.

Cc: Arun Sharma <asharma@fb.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/util/hist.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index a6bb3e329857..daf39fc8fe33 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -624,6 +624,18 @@ static int hist_entry__sort_on_period(struct hist_entry *a,
 	struct hist_entry *pair;
 	u64 *periods_a, *periods_b;
 
+	if (symbol_conf.cumulate_callchain) {
+		/*
+		 * Put caller above callee when they have equal period.
+		 */
+		if (a->stat_acc->period != b->stat_acc->period)
+			return a->stat_acc->period > b->stat_acc->period ? 1 : -1;
+
+		if (a->callchain->max_depth != b->callchain->max_depth)
+			return a->callchain->max_depth < b->callchain->max_depth ?
+				1 : -1;
+	}
+
 	ret = period_cmp(a->stat.period, b->stat.period);
 	if (ret || !symbol_conf.event_group)
 		return ret;
-- 
1.7.11.7