On Thu, Nov 9, 2023 at 5:29 PM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> The fill_link_info test keeps skeleton open and just creates
> various links. We are wrongly calling bpf_link__detach after
> each test to close them, we need to call bpf_link__destroy.
>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
I've just realized that we can use a local link for this particular scenario :)
Feel free to add:
Acked-by: Yafang Shao <laoar.shao@xxxxxxxxx>
> ---
> .../selftests/bpf/prog_tests/fill_link_info.c | 44 ++++++++++---------
> 1 file changed, 23 insertions(+), 21 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/fill_link_info.c b/tools/testing/selftests/bpf/prog_tests/fill_link_info.c
> index 97142a4db374..9294cb8d7743 100644
> --- a/tools/testing/selftests/bpf/prog_tests/fill_link_info.c
> +++ b/tools/testing/selftests/bpf/prog_tests/fill_link_info.c
> @@ -140,14 +140,14 @@ static void test_kprobe_fill_link_info(struct test_fill_link_info *skel,
> .retprobe = type == BPF_PERF_EVENT_KRETPROBE,
> );
> ssize_t entry_offset = 0;
> + struct bpf_link *link;
> int link_fd, err;
>
> - skel->links.kprobe_run = bpf_program__attach_kprobe_opts(skel->progs.kprobe_run,
> - KPROBE_FUNC, &opts);
> - if (!ASSERT_OK_PTR(skel->links.kprobe_run, "attach_kprobe"))
> + link = bpf_program__attach_kprobe_opts(skel->progs.kprobe_run, KPROBE_FUNC, &opts);
> + if (!ASSERT_OK_PTR(link, "attach_kprobe"))
> return;
>
> - link_fd = bpf_link__fd(skel->links.kprobe_run);
> + link_fd = bpf_link__fd(link);
> if (!invalid) {
> /* See also arch_adjust_kprobe_addr(). */
> if (skel->kconfig->CONFIG_X86_KERNEL_IBT)
> @@ -157,39 +157,41 @@ static void test_kprobe_fill_link_info(struct test_fill_link_info *skel,
> } else {
> kprobe_fill_invalid_user_buffer(link_fd);
> }
> - bpf_link__detach(skel->links.kprobe_run);
> + bpf_link__destroy(link);
> }
>
> static void test_tp_fill_link_info(struct test_fill_link_info *skel)
> {
> + struct bpf_link *link;
> int link_fd, err;
>
> - skel->links.tp_run = bpf_program__attach_tracepoint(skel->progs.tp_run, TP_CAT, TP_NAME);
> - if (!ASSERT_OK_PTR(skel->links.tp_run, "attach_tp"))
> + link = bpf_program__attach_tracepoint(skel->progs.tp_run, TP_CAT, TP_NAME);
> + if (!ASSERT_OK_PTR(link, "attach_tp"))
> return;
>
> - link_fd = bpf_link__fd(skel->links.tp_run);
> + link_fd = bpf_link__fd(link);
> err = verify_perf_link_info(link_fd, BPF_PERF_EVENT_TRACEPOINT, 0, 0, 0);
> ASSERT_OK(err, "verify_perf_link_info");
> - bpf_link__detach(skel->links.tp_run);
> + bpf_link__destroy(link);
> }
>
> static void test_uprobe_fill_link_info(struct test_fill_link_info *skel,
> enum bpf_perf_event_type type)
> {
> + struct bpf_link *link;
> int link_fd, err;
>
> - skel->links.uprobe_run = bpf_program__attach_uprobe(skel->progs.uprobe_run,
> - type == BPF_PERF_EVENT_URETPROBE,
> - 0, /* self pid */
> - UPROBE_FILE, uprobe_offset);
> - if (!ASSERT_OK_PTR(skel->links.uprobe_run, "attach_uprobe"))
> + link = bpf_program__attach_uprobe(skel->progs.uprobe_run,
> + type == BPF_PERF_EVENT_URETPROBE,
> + 0, /* self pid */
> + UPROBE_FILE, uprobe_offset);
> + if (!ASSERT_OK_PTR(link, "attach_uprobe"))
> return;
>
> - link_fd = bpf_link__fd(skel->links.uprobe_run);
> + link_fd = bpf_link__fd(link);
> err = verify_perf_link_info(link_fd, type, 0, uprobe_offset, 0);
> ASSERT_OK(err, "verify_perf_link_info");
> - bpf_link__detach(skel->links.uprobe_run);
> + bpf_link__destroy(link);
> }
>
> static int verify_kmulti_link_info(int fd, bool retprobe)
> @@ -278,24 +280,24 @@ static void test_kprobe_multi_fill_link_info(struct test_fill_link_info *skel,
> bool retprobe, bool invalid)
> {
> LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
> + struct bpf_link *link;
> int link_fd, err;
>
> opts.syms = kmulti_syms;
> opts.cnt = KMULTI_CNT;
> opts.retprobe = retprobe;
> - skel->links.kmulti_run = bpf_program__attach_kprobe_multi_opts(skel->progs.kmulti_run,
> - NULL, &opts);
> - if (!ASSERT_OK_PTR(skel->links.kmulti_run, "attach_kprobe_multi"))
> + link = bpf_program__attach_kprobe_multi_opts(skel->progs.kmulti_run, NULL, &opts);
> + if (!ASSERT_OK_PTR(link, "attach_kprobe_multi"))
> return;
>
> - link_fd = bpf_link__fd(skel->links.kmulti_run);
> + link_fd = bpf_link__fd(link);
> if (!invalid) {
> err = verify_kmulti_link_info(link_fd, retprobe);
> ASSERT_OK(err, "verify_kmulti_link_info");
> } else {
> verify_kmulti_invalid_user_buffer(link_fd);
> }
> - bpf_link__detach(skel->links.kmulti_run);
> + bpf_link__destroy(link);
> }
>
> void test_fill_link_info(void)
> --
> 2.41.0
>
--
Regards
Yafang
