Re: [PATCH 3/3] perf-probe: Do not show the skipped events

From: Masami Hiramatsu
Date: Thu Apr 23 2020 - 19:33:11 EST


On Thu, 23 Apr 2020 11:01:39 -0300
Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> wrote:

> Em Thu, Apr 23, 2020 at 08:01:22PM +0900, Masami Hiramatsu escreveu:
> > When a probe point is expanded to several places (like inlined) and
> > if some of them are skipped because of blacklisted or __init function,
> > those trace_events has no event name. It must be skipped while showing
> > results.
> >
> > Without this fix, you can see "(null):(null)" on the list,
> > ===========
>
> Ok, you broke the patch in two, I think its better to combine both, ok?

No, if an inlined function is embedded in blacklisted areas, it also
shows same "(null):(null)" without [2/3].

Reordering the patches is OK, but this is still an independent fix.

Thank you,

>
> - Arnaldo
>
> > # ./perf probe request_resource
> > reserve_setup is out of .text, skip it.
> > Added new events:
> > (null):(null) (on request_resource)
> > probe:request_resource (on request_resource)
> >
> > You can now use it in all perf tools, such as:
> >
> > perf record -e probe:request_resource -aR sleep 1
> >
> > ===========
> >
> > With this fix, it is ignored.
> > ===========
> > # ./perf probe request_resource
> > reserve_setup is out of .text, skip it.
> > Added new events:
> > probe:request_resource (on request_resource)
> >
> > You can now use it in all perf tools, such as:
> >
> > perf record -e probe:request_resource -aR sleep 1
> >
> > ===========
> >
> > Fixes: 5a51fcd1f30c ("perf probe: Skip kernel symbols which is out of .text")
> > Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx
> > ---
> > tools/perf/builtin-probe.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
> > index 70548df2abb9..6b1507566770 100644
> > --- a/tools/perf/builtin-probe.c
> > +++ b/tools/perf/builtin-probe.c
> > @@ -364,6 +364,9 @@ static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs)
> >
> > for (k = 0; k < pev->ntevs; k++) {
> > struct probe_trace_event *tev = &pev->tevs[k];
> > + /* Skipped events have no event name */
> > + if (!tev->event)
> > + continue;
> >
> > /* We use tev's name for showing new events */
> > show_perf_probe_event(tev->group, tev->event, pev,
> >
>
> --
>
> - Arnaldo


--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>