Re: [PATCH v4] perf annotate: Fix missing number of samples for source_line_samples

From: Arnaldo Carvalho de Melo
Date: Tue Mar 28 2017 - 11:29:18 EST


Em Tue, Mar 28, 2017 at 11:21:33PM +0900, Taeung Song escreveu:
>
>
> On 03/28/2017 10:48 PM, Arnaldo Carvalho de Melo wrote:
> > Em Tue, Mar 28, 2017 at 09:12:05PM +0900, Taeung Song escreveu:
> > > The option 'show-total-period' works fine without a option '-l'.
> > > But if running 'perf annotate --stdio -l --show-total-period',
> > > you can see a problem showing only zero '0' for number of samples.
> >
> > If you do that at that point, don't you have to change the TUI not to do
> > it again?
> >
> > - Arnaldo
> >
>
> Yes, there isn't the same problem when using 't' on TUI of 'perf annotate'.
> (As you know, 't' is show-total-period option)

Yeah, there is no problem on the TUI, but since you do it in a function
taht the TUI uses, it may not be needed to do this in
tools/perf/util/annotate.c _and_ in tools/perf/ui/browsers/annotate.c,
right?

- Arnaldo

> In 'annotate' TUI, we can use the 't' functionality without the problem.
> Because of the code (util/annotate.c:911 and ui/browsers/annotate.c:412) as
> below.
>
> 881 double disasm__calc_percent(struct annotation *notes, int evidx, s64
> offset,
> 882 s64 end, const char **path, u64
> *nr_samples)
> 883 {
> ...
> 910 if (h->sum) {
> 911 *nr_samples = hits;
>
> And,
>
> 378 static void annotate_browser__calc_percent(struct annotate_browser
> *browser,
> 379 struct perf_evsel *evsel)
> 380 {
> ...
> 407 bpos->samples[i].percent =
> disasm__calc_percent(notes,
> 408 evsel->idx + i,
> 409 pos->offset,
> 410 next ? next->offset :
> len,
> 411 &path, &nr_samples);
> 412 bpos->samples[i].nr = nr_samples;
>
>
> And 'perf annotate --stdio --show-total-period' hasn't the problem, too.
> Because of the same code (util/annotate.c:911).
>
>
> But if with '-l', i.e. 'perf annotate --stdio -l --show-total-period',
> the problem happen. Because 'nr' of source_line_samples aren't ordinarily
> set
> in symbol__get_source_line() (util/annotate.c:1634~..)
> ,so fix it as this patch
>
> Are there something I missed or misunderstand ?
>
>
> Thanks,
> Taeung
>
>
> > > Before:
> > > $ perf annotate --stdio -l --show-total-period
> > > ...
> > > 0 : 400816: push %rbp
> > > 0 : 400817: mov %rsp,%rbp
> > > 0 : 40081a: mov %edi,-0x24(%rbp)
> > > 0 : 40081d: mov %rsi,-0x30(%rbp)
> > > 0 : 400821: mov -0x24(%rbp),%eax
> > > 0 : 400824: mov -0x30(%rbp),%rdx
> > > 0 : 400828: mov (%rdx),%esi
> > > 0 : 40082a: mov $0x0,%edx
> > > ...
> > >
> > > The reason is it was missed to set number of samples
> > > of source_line_samples, so set it ordinarily.
> > >
> > > After:
> > > $ perf annotate --stdio -l --show-total-period
> > > ...
> > > 3 : 400816: push %rbp
> > > 4 : 400817: mov %rsp,%rbp
> > > 0 : 40081a: mov %edi,-0x24(%rbp)
> > > 0 : 40081d: mov %rsi,-0x30(%rbp)
> > > 1 : 400821: mov -0x24(%rbp),%eax
> > > 2 : 400824: mov -0x30(%rbp),%rdx
> > > 0 : 400828: mov (%rdx),%esi
> > > 1 : 40082a: mov $0x0,%edx
> > > ...
> > >
> > > Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
> > > Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
> > > Cc: Martin Liska <mliska@xxxxxxx>
> > > Fixes: 0c4a5bcea460 ("perf annotate: Display total number of samples with --show-total-period")
> > > Signed-off-by: Taeung Song <treeze.taeung@xxxxxxxxx>
> > > ---
> > > tools/perf/util/annotate.c | 6 ++++--
> > > tools/perf/util/annotate.h | 2 +-
> > > 2 files changed, 5 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
> > > index 11af5f0..a37032b 100644
> > > --- a/tools/perf/util/annotate.c
> > > +++ b/tools/perf/util/annotate.c
> > > @@ -1665,7 +1665,7 @@ 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;
> > > + u64 offset, nr_samples;
> > > double percent_max = 0.0;
> > >
> > > src_line->nr_pcnt = nr_pcnt;
> > > @@ -1674,12 +1674,14 @@ 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];
> > > if (h->sum)
> > > - percent = 100.0 * h->addr[i] / h->sum;
> > > + percent = 100.0 * nr_samples / h->sum;
> > >
> > > if (percent > percent_max)
> > > percent_max = percent;
> > > src_line->samples[k].percent = percent;
> > > + src_line->samples[k].nr = nr_samples;
> > > }
> > >
> > > if (percent_max <= 0.5)
> > > diff --git a/tools/perf/util/annotate.h b/tools/perf/util/annotate.h
> > > index 09776b5..948aa8e 100644
> > > --- a/tools/perf/util/annotate.h
> > > +++ b/tools/perf/util/annotate.h
> > > @@ -98,7 +98,7 @@ struct cyc_hist {
> > > struct source_line_samples {
> > > double percent;
> > > double percent_sum;
> > > - double nr;
> > > + u64 nr;
> > > };
> > >
> > > struct source_line {
> > > --
> > > 2.7.4