Messages in this thread | | | From | Namhyung Kim <> | Date | Tue, 6 Sep 2022 11:31:04 -0700 | Subject | Re: [PATCH] perf test: Skip sigtrap test on old kernels |
| |
On Tue, Sep 6, 2022 at 5:45 AM Arnaldo Carvalho de Melo <acme@kernel.org> wrote: > > Em Sat, Sep 03, 2022 at 08:52:01AM +0200, Marco Elver escreveu: > > On Sat, 3 Sept 2022 at 02:02, Namhyung Kim <namhyung@kernel.org> wrote: > > > > > > If it runs on an old kernel, perf_event_open would fail because of the > > > new fields sigtrap and sig_data. Just skip the test if it failed. > > > > > > Cc: Marco Elver <elver@google.com> > > > Signed-off-by: Namhyung Kim <namhyung@kernel.org> > > > --- > > > tools/perf/tests/sigtrap.c | 1 + > > > 1 file changed, 1 insertion(+) > > > > > > diff --git a/tools/perf/tests/sigtrap.c b/tools/perf/tests/sigtrap.c > > > index e32ece90e164..7057566e6ae4 100644 > > > --- a/tools/perf/tests/sigtrap.c > > > +++ b/tools/perf/tests/sigtrap.c > > > @@ -140,6 +140,7 @@ static int test__sigtrap(struct test_suite *test __maybe_unused, int subtest __m > > > fd = sys_perf_event_open(&attr, 0, -1, -1, perf_event_open_cloexec_flag()); > > > if (fd < 0) { > > > pr_debug("FAILED sys_perf_event_open(): %s\n", str_error_r(errno, sbuf, sizeof(sbuf))); > > > + ret = TEST_SKIP; > > > > Wouldn't we be interested if perf_event_open() fails because it could > > actually be a bug? By skipping we'll be more likely to miss the fact > > there's a real problem. > > > > That's my naive thinking at least - what do other perf tests usually > > do in this case? > > Yeah, I was going to try and check if this is the only way that, with > the given arguments, perf_event_open would fail, but its better to at > least check errno against -EINVAL or something?
EINVAL would be too generic and the kernel returns it in many places. I really wish we could have a better error reporting mechanism.
Maybe we could retry perf_event_open with sigtrap and sig_data cleared. If it succeeded, then we can skip the test. If it still failed, then report the error. But it still couldn't find a bug in the sigtrap code. What do you think?
Thanks, Namhyung
| |