perf stat: Add branch performance metric
When we count both branches and branch-misses it is useful to
print out the percentage of branch-misses:
# perf stat -e branches -e branch-misses /bin/true
Performance counter stats for '/bin/true':
401684 branches # 0.000 M/sec
23301 branch-misses # 5.801 %
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: paulus@samba.org
Cc: a.p.zijlstra@chello.nl
LKML-Reference: <20091018112923.GQ4808@kryten>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 3db31e7..c373683 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -125,6 +125,7 @@
struct stats runtime_nsecs_stats;
struct stats walltime_nsecs_stats;
struct stats runtime_cycles_stats;
+struct stats runtime_branches_stats;
#define MATCH_EVENT(t, c, counter) \
(attrs[counter].type == PERF_TYPE_##t && \
@@ -235,6 +236,8 @@
update_stats(&runtime_nsecs_stats, count[0]);
if (MATCH_EVENT(HARDWARE, HW_CPU_CYCLES, counter))
update_stats(&runtime_cycles_stats, count[0]);
+ if (MATCH_EVENT(HARDWARE, HW_BRANCH_INSTRUCTIONS, counter))
+ update_stats(&runtime_branches_stats, count[0]);
}
static int run_perf_stat(int argc __used, const char **argv)
@@ -352,6 +355,14 @@
ratio = avg / total;
fprintf(stderr, " # %10.3f IPC ", ratio);
+ } else if (MATCH_EVENT(HARDWARE, HW_BRANCH_MISSES, counter)) {
+ total = avg_stats(&runtime_branches_stats);
+
+ if (total)
+ ratio = avg * 100 / total;
+
+ fprintf(stderr, " # %10.3f %% ", ratio);
+
} else {
total = avg_stats(&runtime_nsecs_stats);