Re: [PATCH bpf-next 2/4] selftests/bpf: test_progs: test__skip

[Andrii Nakryiko <andrii.nakryiko@gmail.com>]

On Wed, Aug 14, 2019 at 12:53 PM Stanislav Fomichev <sdf@fomichev.me> wrote:
>
> On 08/14, Andrii Nakryiko wrote:
> > On Wed, Aug 14, 2019 at 12:22 PM Andrii Nakryiko
> > <andrii.nakryiko@gmail.com> wrote:
> > >
> > > On Wed, Aug 14, 2019 at 9:48 AM Stanislav Fomichev <sdf@google.com> wrote:
> > > >
> > > > Export test__skip() to indicate skipped tests and use it in
> > > > test_send_signal_nmi().
> > > >
> > > > Cc: Andrii Nakryiko <andriin@fb.com>
> > > > Signed-off-by: Stanislav Fomichev <sdf@google.com>
> > > > ---
> > >
> > > For completeness, we should probably also support test__skip_subtest()
> > > eventually, but it's fine until we don't have a use case.
> >
> > Hm.. so I think we don't need separate test__skip_subtest().
> > test__skip() should skip either test or sub-test, depending on which
> > context we are running in. So maybe just make sure this is handled
> > correctly?
> Do we care if it's a test or a subtest skip? My motivation was to
> have a counter that can be examined to make sure we have a full test
> coverage, so when people run the tests they can be sure that nothing
> is skipped due to missing config or something else.

I think we do. We might convert, e.g., test_btf to be one big test
with lots of sub-tests. Some of those might be legitimately skipped.
Having just "1 test skipped" message is not helpful, when there are
170 sub-tests that were not.

>
> Let me know if you see a value in highlighting test vs subtest skip.
>
> Other related question is: should we do verbose output in case
> of a skip? Right now we don't do it.

It might be useful, I guess, especially if it's not too common. But
Alexei is way more picky about stuff like that, so I'd defer to him. I
have no problem with a clean "SKIPPED: <test>/<subtest> (maybe some
reason for skipping here)" message.

>
> > >
> > > Acked-by: Andrii Nakryiko <andriin@fb.com>
> > >
> > > >  tools/testing/selftests/bpf/prog_tests/send_signal.c | 1 +
> > > >  tools/testing/selftests/bpf/test_progs.c             | 9 +++++++--
> > > >  tools/testing/selftests/bpf/test_progs.h             | 2 ++
> > > >  3 files changed, 10 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/tools/testing/selftests/bpf/prog_tests/send_signal.c b/tools/testing/selftests/bpf/prog_tests/send_signal.c
> > > > index 1575f0a1f586..40c2c5efdd3e 100644
> > > > --- a/tools/testing/selftests/bpf/prog_tests/send_signal.c
> > > > +++ b/tools/testing/selftests/bpf/prog_tests/send_signal.c
> > > > @@ -204,6 +204,7 @@ static int test_send_signal_nmi(void)
> > > >                 if (errno == ENOENT) {
> > > >                         printf("%s:SKIP:no PERF_COUNT_HW_CPU_CYCLES\n",
> > > >                                __func__);
> > > > +                       test__skip();
> > > >                         return 0;
> > > >                 }
> > > >                 /* Let the test fail with a more informative message */
> > > > diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
> > > > index 1a7a2a0c0a11..1993f2ce0d23 100644
> > > > --- a/tools/testing/selftests/bpf/test_progs.c
> > > > +++ b/tools/testing/selftests/bpf/test_progs.c
> > > > @@ -121,6 +121,11 @@ void test__force_log() {
> > > >         env.test->force_log = true;
> > > >  }
> > > >
> > > > +void test__skip(void)
> > > > +{
> > > > +       env.skip_cnt++;
> > > > +}
> > > > +
> > > >  struct ipv4_packet pkt_v4 = {
> > > >         .eth.h_proto = __bpf_constant_htons(ETH_P_IP),
> > > >         .iph.ihl = 5,
> > > > @@ -535,8 +540,8 @@ int main(int argc, char **argv)
> > > >                         test->test_name);
> > > >         }
> > > >         stdio_restore();
> > > > -       printf("Summary: %d/%d PASSED, %d FAILED\n",
> > > > -              env.succ_cnt, env.sub_succ_cnt, env.fail_cnt);
> > > > +       printf("Summary: %d/%d PASSED, %d SKIPPED, %d FAILED\n",
> >
> > So because some sub-tests might be skipped, while others will be
> > running, let's keep output consistent with SUCCESS and use
> > <test>/<subtests> format for SKIPPED as well?
> >
> > > > +              env.succ_cnt, env.sub_succ_cnt, env.skip_cnt, env.fail_cnt);
> > > >
> > > >         free(env.test_selector.num_set);
> > > >         free(env.subtest_selector.num_set);
> > > > diff --git a/tools/testing/selftests/bpf/test_progs.h b/tools/testing/selftests/bpf/test_progs.h
> > > > index 37d427f5a1e5..9defd35cb6c0 100644
> > > > --- a/tools/testing/selftests/bpf/test_progs.h
> > > > +++ b/tools/testing/selftests/bpf/test_progs.h
> > > > @@ -64,6 +64,7 @@ struct test_env {
> > > >         int succ_cnt; /* successful tests */
> > > >         int sub_succ_cnt; /* successful sub-tests */
> > > >         int fail_cnt; /* total failed tests + sub-tests */
> > > > +       int skip_cnt; /* skipped tests */
> > > >  };
> > > >
> > > >  extern int error_cnt;
> > > > @@ -72,6 +73,7 @@ extern struct test_env env;
> > > >
> > > >  extern void test__force_log();
> > > >  extern bool test__start_subtest(const char *name);
> > > > +extern void test__skip(void);
> > > >
> > > >  #define MAGIC_BYTES 123
> > > >
> > > > --
> > > > 2.23.0.rc1.153.gdeed80330f-goog
> > > >