Re: [PATCH bpf-next] selftests/bpf: Add missing bpf_iter_vma_offset__destroy call

Andrii Nakryiko
2022-10-05T22:59:04Z

On Tue, Oct 4, 2022 at 5:16 AM Jiri Olsa <olsajiri@gmail.com> wrote:
>
> On Tue, Oct 04, 2022 at 08:38:23AM +0200, Jiri Olsa wrote:
> > On Mon, Oct 03, 2022 at 05:12:44PM -0700, Martin KaFai Lau wrote:
> > > On 10/2/22 8:11 AM, Jiri Olsa wrote:
> > > > Adding missing bpf_iter_vma_offset__destroy call to
> > > > test_task_vma_offset_common function and related goto jumps.
> > > >
> > > > Fixes: b3e1331eb925 ("selftests/bpf: Test parameterized task BPF iterators.")
> > > > Cc: Kui-Feng Lee <kuifeng@fb.com>
> > > > Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> > > > ---
> > > > tools/testing/selftests/bpf/prog_tests/bpf_iter.c | 8 +++++---
> > > > 1 file changed, 5 insertions(+), 3 deletions(-)
> > > >
> > > > diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
> > > > index 3369c5ec3a17..462fe92e0736 100644
> > > > --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
> > > > +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
> > > > @@ -1515,11 +1515,11 @@ static void test_task_vma_offset_common(struct bpf_iter_attach_opts *opts, bool
> > > > link = bpf_program__attach_iter(skel->progs.get_vma_offset, opts);
> > >
> > > Thanks for the fix.
> > >
> > > A nit. Instead of adding a new goto label. How about doing
> > >
> > > skel->links.get_vma_offset = bpf_program_attach_iter(...)
> > >
> > > and bpf_iter_vma_offset__destroy(skel) will take care of the link destroy.
> > > The earlier test_task_vma_common() is doing that also.
> >
> > right, I forgot destroy would do that.. it'll be simpler change
>
> ugh actually no ;-) it's outside (of skeleton) link,
> so it won't get closed in bpf_iter_vma_offset__destroy

Martin's point was that if you assign it to skel->links.get_vma_offset
it will be closed by skeleton's destroy method. So let's do that?

>
> the earlier test_task_vma_common does not create such link
>
> jirka
>
> >
> > thanks,
> > jirka
> >
> > >
> > > Kui-Feng, please also take a look.
> > >
> > > > if (!ASSERT_OK_PTR(link, "attach_iter"))
> > > > - return;
> > > > + goto exit_skel;
> > > > iter_fd = bpf_iter_create(bpf_link__fd(link));
> > > > if (!ASSERT_GT(iter_fd, 0, "create_iter"))
> > > > - goto exit;
> > > > + goto exit_link;
> > > > while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
> > > > ;
> > > > @@ -1534,8 +1534,10 @@ static void test_task_vma_offset_common(struct bpf_iter_attach_opts *opts, bool
> > > > close(iter_fd);
> > > > -exit:
> > > > +exit_link:
> > > > bpf_link__destroy(link);
> > > > +exit_skel:
> > > > + bpf_iter_vma_offset__destroy(skel);
> > > > }
> > > > static void test_task_vma_offset(void)
> > >