On Tue, 2022-04-12 at 20:17 -0700, Andrii Nakryiko wrote:
> On Tue, Apr 12, 2022 at 9:56 AM Kui-Feng Lee <kuifeng@xxxxxx> wrote:
> >
> > Make sure BPF cookies are correct for fentry/fexit/fmod_ret.
> >
> > Signed-off-by: Kui-Feng Lee <kuifeng@xxxxxx>
> > ---
> > .../selftests/bpf/prog_tests/bpf_cookie.c | 52
> > +++++++++++++++++++
> > .../selftests/bpf/progs/test_bpf_cookie.c | 24 +++++++++
> > 2 files changed, 76 insertions(+)
> >
> > diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> > b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> > index 923a6139b2d8..7f05056c66d4 100644
> > --- a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> > +++ b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> > @@ -410,6 +410,56 @@ static void pe_subtest(struct test_bpf_cookie
> > *skel)
> > bpf_link__destroy(link);
> > }
> >
> > +static void tracing_subtest(struct test_bpf_cookie *skel)
> > +{
> > + __u64 cookie;
> > + int prog_fd;
> > + int fentry_fd = -1, fexit_fd = -1, fmod_ret_fd = -1;
> > +
>
> unnecessary empty line
Got it!
>
> > + LIBBPF_OPTS(bpf_test_run_opts, opts, .repeat = 1);
>
> .repeat = 1 is not necessary, I think, .repeat = 0 is equivalent to
> that
I will test it.
>
> > + LIBBPF_OPTS(bpf_link_create_opts, link_opts);
> > +
> > + skel->bss->fentry_res = 0;
> > + skel->bss->fexit_res = 0;
> > +
> > + cookie = 0x100000;
>
> nit: make this value bigger to make sure higher 32 bits of u64 are
> preserved properly. Maybe 0x1000000010000000 (and similarly with 2
> and
> 3)
Ok!
>
> > + prog_fd = bpf_program__fd(skel->progs.fentry_test1);
> > + link_opts.tracing.bpf_cookie = cookie;
> > + fentry_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_FENTRY,
> > &link_opts);
> > +
>
> ASSERT_GE?
sure!
>
> > + cookie = 0x200000;
> > + prog_fd = bpf_program__fd(skel->progs.fexit_test1);
> > + link_opts.tracing.bpf_cookie = cookie;
> > + fexit_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_FEXIT,
> > &link_opts);
> > + if (!ASSERT_GE(fexit_fd, 0, "fexit.open"))
> > + goto cleanup;
> > +
>
> [...]
