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

From: Namhyung Kim
Date: Tue Jul 18 2017 - 12:24:44 EST


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.


>
> 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..


> 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


> - 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
>