Re: [PATCH v2 9/9] perf annotate: Use the sample period when calculating the percentage

From: Taeung Song
Date: Wed Jul 19 2017 - 13:34:15 EST




On 07/19/2017 01:23 AM, Namhyung Kim wrote:
On Fri, Jul 14, 2017 at 02:46:20AM +0900, Taeung Song wrote:
Currently the percentages of perf-annotate are calculated
with number of samples, not the sample period.
So fix it to correspond with perf-report using the sample period
for the calculation.

Not sure someone still wants the old behavior. Maybe it'd be better
to honor --show-nr-samples option.



You mean that if users use --show-nr-samples option,
we can calculate the percent values with number of samples, right ?


Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Signed-off-by: Taeung Song <treeze.taeung@xxxxxxxxx>
---
tools/perf/util/annotate.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index d9bdedf..28a6d11 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -988,7 +988,7 @@ double disasm__calc_percent(struct annotation *notes, int evidx, s64 offset,
if (h->total_samples) {

It seems checking total_period here is clearer and safer. But I guess
it would have same effect 99.9% but still..



I got it.


sample->nr_samples = hits;
sample->period = p;
- percent = 100.0 * hits / h->total_samples;
+ percent = 100.0 * p / h->total_period;
}
}
@@ -1730,8 +1730,9 @@ static int symbol__get_source_line(struct symbol *sym, struct map *map,
start = map__rip_2objdump(map, sym->start);
for (i = 0; i < len; i++) {
- u64 offset, nr_samples;
+ u64 offset;
double percent_max = 0.0;
+ struct sym_hist_entry sample;
src_line->nr_pcnt = nr_pcnt;
@@ -1739,15 +1740,15 @@ static int symbol__get_source_line(struct symbol *sym, struct map *map,
double percent = 0.0;
h = annotation__histogram(notes, evidx + k);
- nr_samples = h->addr[i].nr_samples;
+ sample = h->addr[i];
if (h->total_samples)

Ditto.

Thanks,
Namhyung



ok

Thanks,
Taeung

- percent = 100.0 * nr_samples / h->total_samples;
+ percent = 100.0 * sample.period / h->total_period;
if (percent > percent_max)
percent_max = percent;
src_line->samples[k].percent = percent;
- src_line->samples[k].nr = nr_samples;
+ src_line->samples[k].nr = sample.nr_samples;
}
if (percent_max <= 0.5)
--
2.7.4