Re: [PATCH bpf-next 4/4] selftests/bpf: Allow to benchmark trigger with stacktrace

[Jiri Olsa <olsajiri@gmail.com>]

On Thu, Jan 15, 2026 at 10:48:29AM -0800, Andrii Nakryiko wrote:
> On Mon, Jan 12, 2026 at 1:50 PM Jiri Olsa <jolsa@kernel.org> wrote:
> >
> > Adding support to call bpf_get_stackid helper from trigger programs,
> > so far added for kprobe multi.
> >
> > Adding the --stacktrace/-g option to enable it.
> >
> > Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> > ---
> >  tools/testing/selftests/bpf/bench.c            |  4 ++++
> >  tools/testing/selftests/bpf/bench.h            |  1 +
> >  .../selftests/bpf/benchs/bench_trigger.c       |  1 +
> >  .../selftests/bpf/progs/trigger_bench.c        | 18 ++++++++++++++++++
> >  4 files changed, 24 insertions(+)
> >
> 
> This now actually becomes a stack trace benchmark :) But I don't mind,
> I think it would be good to be able to benchmark this. But I think we
> should then implement it for all different tracing programs (tp,
> raw_tp, fentry/fexit/fmod_ret) for consistency and so we can compare
> and contrast?...

yep, agreed

> 
> > diff --git a/tools/testing/selftests/bpf/bench.c b/tools/testing/selftests/bpf/bench.c
> > index bd29bb2e6cb5..8dadd9c928ec 100644
> > --- a/tools/testing/selftests/bpf/bench.c
> > +++ b/tools/testing/selftests/bpf/bench.c
> > @@ -265,6 +265,7 @@ static const struct argp_option opts[] = {
> >         { "verbose", 'v', NULL, 0, "Verbose debug output"},
> >         { "affinity", 'a', NULL, 0, "Set consumer/producer thread affinity"},
> >         { "quiet", 'q', NULL, 0, "Be more quiet"},
> > +       { "stacktrace", 'g', NULL, 0, "Get stack trace"},
> 
> bikeshedding time: why "g"? why not -S or something like that?

perf tool strikes back ;-) -S is better

thanks,
jirka