perf annotate: Record the min/max cycles

Currently perf has a feature to account cycles for LBRs

For example, on skylake:

  perf record -b ...
  perf report or perf annotate

And then browsing the annotate browser gives average cycle counts for
program blocks.

For some analysis it would be useful if we could know not only the
average cycles but also the min and max cycles.

This patch records the min and max cycles.

Signed-off-by: Jin Yao <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
[ Switch from max/min to min/max ]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

1 files changed, 13 insertions, 1 deletions

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 5d74a30fe00f..4fcfefea3bc2 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -760,6 +760,15 @@ static int __symbol__account_cycles(struct annotation *notes,
 	ch[offset].num_aggr++;
 	ch[offset].cycles_aggr += cycles;
 
+	if (cycles > ch[offset].cycles_max)
+		ch[offset].cycles_max = cycles;
+
+	if (ch[offset].cycles_min) {
+		if (cycles && cycles < ch[offset].cycles_min)
+			ch[offset].cycles_min = cycles;
+	} else
+		ch[offset].cycles_min = cycles;
+
 	if (!have_start && ch[offset].have_start)
 		return 0;
 	if (ch[offset].num) {
@@ -953,8 +962,11 @@ void annotation__compute_ipc(struct annotation *notes, size_t size)
 			if (ch->have_start)
 				annotation__count_and_fill(notes, ch->start, offset, ch);
 			al = notes->offsets[offset];
-			if (al && ch->num_aggr)
+			if (al && ch->num_aggr) {
 				al->cycles = ch->cycles_aggr / ch->num_aggr;
+				al->cycles_max = ch->cycles_max;
+				al->cycles_min = ch->cycles_min;
+			}
 			notes->have_cycles = true;
 		}
 	}