Re: [PATCH v2] perf test: Fix inet_pton probe failure and unroll call graph

On Sat, Apr 11, 2026 at 12:54 PM <[email protected]> wrote:
>
> Sashiko AI review found 1 potential issue(s):
> - [Medium] Unconditionally requiring DWARF call-graphs causes the test to falsely fail on perf builds lacking DWARF support.
> --
>
> commit dbec7073d294917f7866e8ea3a6b39004a7407ad
> Author: Ian Rogers <[email protected]>
>
> perf test: Fix inet_pton probe failure and unroll call graph
>
> This commit fixes an issue where multiple identical event names were output
> by perf probe when creating multiple probe points, which broke subsequent
> commands. It also updates the backtrace collection to explicitly request
> dwarf call-graphs and increases max-stack to 8 for all architectures.
>
> > diff --git a/tools/perf/tests/shell/record+probe_libc_inet_pton.sh b/tools/perf/tests/shell/record+probe_libc_inet_pton.sh
> > index ab99bef556bf0..eca629ee83f03 100755
> > --- a/tools/perf/tests/shell/record+probe_libc_inet_pton.sh
> > +++ b/tools/perf/tests/shell/record+probe_libc_inet_pton.sh
> [ ... ]
> > @@ -40,12 +40,12 @@ trace_libc_inet_pton_backtrace() {
> >       echo ".*inet_pton\+0x[[:xdigit:]]+[[:space:]]\($libc|inlined\)$" >> $expected
> >       case "$(uname -m)" in
> >       s390x)
> > -             eventattr='call-graph=dwarf,max-stack=4'
> > +             eventattr='call-graph=dwarf,max-stack=8'
> >               echo "((__GI_)?getaddrinfo|text_to_binary_address)\+0x[[:xdigit:]]+[[:space:]]\($libc|inlined\)$" >> $expected
> >               echo "(gaih_inet|main)\+0x[[:xdigit:]]+[[:space:]]\(inlined|.*/bin/ping.*\)$" >> $expected
> >               ;;
> >       *)
> > -             eventattr='max-stack=4'
> > +             eventattr='call-graph=dwarf,max-stack=8'
>
> Will this cause the test to falsely fail on perf builds lacking DWARF support?
>
> If perf is compiled without libunwind or libdw, running perf record with
> call-graph=dwarf will exit with an error. Since the test script doesn't
> appear to verify DWARF support before running, the test will report a hard
> failure rather than gracefully skipping on minimal perf builds.

Since perf probe requires libdw and libunwind is deprecated this isn't
a concern.

Thanks,
Ian

> >               echo ".*(\+0x[[:xdigit:]]+|\[unknown\])[[:space:]]\(.*/bin/ping.*\)$" >> $expected
> >               ;;
> >       esac
>
> --
> Sashiko AI review · https://sashiko.dev/#/patchset/[email protected]?part=1