Re: [PATCH v2 5/5] perf evlist: Add -T/--trace option to show trace fields

From: Arnaldo Carvalho de Melo
Date: Tue Jan 05 2016 - 20:53:09 EST


Em Wed, Jan 06, 2016 at 09:00:31AM +0900, Namhyung Kim escreveu:
> On Tue, Jan 05, 2016 at 07:23:33PM -0300, Arnaldo Carvalho de Melo wrote:
> > Em Tue, Jan 05, 2016 at 07:58:38PM +0900, Namhyung Kim escreveu:
> > > To use dynamic sort keys, it might be good to add an option to see the
> > > list of field names.
> > >
> > > $ perf evlist -T -i perf.data.sched
> >
> > Humm, I think here we should just use --trace_fields, like what appears
> > in the output for each line below, and also as is the case for the '-s
> > trace_fields' case, ok?
>
> OK
>
> >
> > With:
> >
> > $ . ~/git/linux/tools/perf/perf-completion.sh
> > [acme@zoo linux]$ perf evlist --
> > --force --freq --group --input --verbose
> > [acme@zoo linux]$ perf evlist --
> >
> > We can autocomplete it from --t<TAB> anyway :)
> >
> > Unsure about '-T', perhaps this is so specialized, that can remain with
> > just the long option?
>
> OK
>
> >
> > Perhaps we can add a tip, when we run:
> >
> > perf evlist
> >
> > And there are tracepoint events, something like:
> >
> > perf evlist -v
> > sched:sched_switch ...
> > # Tip use 'perf evlist --trace_fields' to show fields for events such
> > # as "sched:sched_switch"
>
> OK, it'd display this only the evlist has tracepoints. How about this oneliner?
>
> # Tip: use 'perf evlist --trace_fields' to show fields for tracepoint events

Sure, I tried using the name of the existing event, "sched:sched_switch"
in this case, to get even closer to what to pass to --trace_fields :-)

> Thanks,
> Namhyung
>
>
> >
> > - Arnaldo
> >
> > > sched:sched_switch: trace_fields=prev_comm,prev_pid,prev_prio,prev_state,next_comm,next_pid,next_prio
> > > sched:sched_stat_wait: trace_fields=comm,pid,delay
> > > sched:sched_stat_sleep: trace_fields=comm,pid,delay
> > > sched:sched_stat_iowait: trace_fields=comm,pid,delay
> > > sched:sched_stat_runtime: trace_fields=comm,pid,runtime,vruntime
> > > sched:sched_process_fork: trace_fields=parent_comm,parent_pid,child_comm,child_pid
> > > sched:sched_wakeup: trace_fields=comm,pid,prio,success,target_cpu
> > > sched:sched_wakeup_new: trace_fields=comm,pid,prio,success,target_cpu
> > > sched:sched_migrate_task: trace_fields=comm,pid,prio,orig_cpu,dest_cpu
> > >
> > > Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> > > Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> > > ---
> > > tools/perf/Documentation/perf-evlist.txt | 4 ++++
> > > tools/perf/builtin-evlist.c | 1 +
> > > tools/perf/util/evsel.c | 23 +++++++++++++++++++++++
> > > tools/perf/util/evsel.h | 1 +
> > > 4 files changed, 29 insertions(+)
> > >
> > > diff --git a/tools/perf/Documentation/perf-evlist.txt b/tools/perf/Documentation/perf-evlist.txt
> > > index 1ceb3700ffbb..b0d99c276cf5 100644
> > > --- a/tools/perf/Documentation/perf-evlist.txt
> > > +++ b/tools/perf/Documentation/perf-evlist.txt
> > > @@ -32,6 +32,10 @@ OPTIONS
> > > --group::
> > > Show event group information.
> > >
> > > +-T::
> > > +--trace::
> > > + Show tracepoint field names.
> > > +
> > > SEE ALSO
> > > --------
> > > linkperf:perf-record[1], linkperf:perf-list[1],
> > > diff --git a/tools/perf/builtin-evlist.c b/tools/perf/builtin-evlist.c
> > > index 08a7d36a2cf8..2820bb2d8cf8 100644
> > > --- a/tools/perf/builtin-evlist.c
> > > +++ b/tools/perf/builtin-evlist.c
> > > @@ -49,6 +49,7 @@ int cmd_evlist(int argc, const char **argv, const char *prefix __maybe_unused)
> > > OPT_BOOLEAN('g', "group", &details.event_group,
> > > "Show event group information"),
> > > OPT_BOOLEAN('f', "force", &details.force, "don't complain, do it"),
> > > + OPT_BOOLEAN('T', "trace", &details.trace, "Show tracepoint fields"),
> > > OPT_END()
> > > };
> > > const char * const evlist_usage[] = {
> > > diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> > > index 544e4400de13..174d0029e038 100644
> > > --- a/tools/perf/util/evsel.c
> > > +++ b/tools/perf/util/evsel.c
> > > @@ -2298,6 +2298,29 @@ int perf_evsel__fprintf(struct perf_evsel *evsel,
> > > printed += comma_fprintf(fp, &first, " %s=%" PRIu64,
> > > term, (u64)evsel->attr.sample_freq);
> > > }
> > > +
> > > + if (details->trace) {
> > > + struct format_field *field;
> > > +
> > > + if (evsel->attr.type != PERF_TYPE_TRACEPOINT) {
> > > + printed += comma_fprintf(fp, &first, " (not a tracepoint)");
> > > + goto out;
> > > + }
> > > +
> > > + field = evsel->tp_format->format.fields;
> > > + if (field == NULL) {
> > > + printed += comma_fprintf(fp, &first, " (no trace field)");
> > > + goto out;
> > > + }
> > > +
> > > + printed += comma_fprintf(fp, &first, " trace_fields=%s", field->name);
> > > +
> > > + field = field->next;
> > > + while (field) {
> > > + printed += comma_fprintf(fp, &first, "%s", field->name);
> > > + field = field->next;
> > > + }
> > > + }
> > > out:
> > > fputc('\n', fp);
> > > return ++printed;
> > > diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
> > > index 5ded1fc0341e..9b36dd584d4a 100644
> > > --- a/tools/perf/util/evsel.h
> > > +++ b/tools/perf/util/evsel.h
> > > @@ -369,6 +369,7 @@ struct perf_attr_details {
> > > bool verbose;
> > > bool event_group;
> > > bool force;
> > > + bool trace;
> > > };
> > >
> > > int perf_evsel__fprintf(struct perf_evsel *evsel,
> > > --
> > > 2.6.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/