[PATCH v1 1/2] perf annotate: Record the max/min cycles

[Jin Yao]

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 max and min cycles.

This patch records the max and min cycles.

Signed-off-by: Jin Yao <yao....@linux.intel.com>
---
 tools/perf/util/annotate.c | 14 +++++++++++++-
 tools/perf/util/annotate.h |  4 ++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 536ee14..934a172 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;
                }
        }
diff --git a/tools/perf/util/annotate.h b/tools/perf/util/annotate.h
index f28a9e4..d50363d 100644
--- a/tools/perf/util/annotate.h
+++ b/tools/perf/util/annotate.h
@@ -105,6 +105,8 @@ struct annotation_line {
        int                      jump_sources;
        float                    ipc;
        u64                      cycles;
+       u64                      cycles_max;
+       u64                      cycles_min;
        size_t                   privsize;
        char                    *path;
        u32                      idx;
@@ -186,6 +188,8 @@ struct cyc_hist {
        u64     start;
        u64     cycles;
        u64     cycles_aggr;
+       u64     cycles_max;
+       u64     cycles_min;
        u32     num;
        u32     num_aggr;
        u8      have_start;
-- 
2.7.4