On Sat, Jul 11, 2026 at 08:48:22PM +0800, Leon Hwang wrote: > Verify that there's no any issue to attach tracing_multi link, then attach > fentry link. > > Assisted-by: Codex:gpt-5.6-sol > Signed-off-by: Leon Hwang <[email protected]>
Acked-by: Jiri Olsa <[email protected]> thanks, jirka > --- > .../selftests/bpf/prog_tests/tracing_multi.c | 69 +++++++++++++++++++ > .../progs/tracing_multi_intersect_attach.c | 8 +++ > 2 files changed, 77 insertions(+) > > diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c > b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c > index f02ffc7f41d7..0aa9532a05cf 100644 > --- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c > +++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c > @@ -460,6 +460,73 @@ static void test_intersect(void) > tracing_multi_intersect__destroy(skel); > } > > +static void test_fentry_after_multi(void) > +{ > + static const char * const funcs[] = { > + "bpf_fentry_test1", > + }; > + struct bpf_link *fentry_link = NULL, *multi_link = NULL; > + struct tracing_multi_intersect *skel = NULL; > + LIBBPF_OPTS(bpf_tracing_multi_opts, opts); > + LIBBPF_OPTS(bpf_test_run_opts, topts); > + __u32 *ids = NULL; > + int err; > + > + skel = tracing_multi_intersect__open_and_load(); > + if (!ASSERT_OK_PTR(skel, "tracing_multi_intersect__open_and_load")) > + return; > + > + skel->bss->pid = getpid(); > + > + ids = get_ids(funcs, ARRAY_SIZE(funcs), NULL); > + if (!ASSERT_OK_PTR(ids, "get_ids")) > + goto cleanup; > + > + opts.ids = ids; > + opts.cnt = ARRAY_SIZE(funcs); > + multi_link = bpf_program__attach_tracing_multi(skel->progs.fentry_1, > NULL, &opts); > + if (!ASSERT_OK_PTR(multi_link, "attach_multi")) > + goto cleanup; > + > + fentry_link = bpf_program__attach(skel->progs.fentry); > + if (!ASSERT_OK_PTR(fentry_link, "attach_fentry")) > + goto cleanup; > + > + err = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.fentry_1), > &topts); > + if (!ASSERT_OK(err, "test_run")) > + goto cleanup; > + ASSERT_EQ(skel->bss->test_result_fentry_1, 1, "multi_fentry"); > + ASSERT_EQ(skel->bss->test_result_fentry, 1, "fentry"); > + > + err = bpf_link__destroy(fentry_link); > + fentry_link = NULL; > + if (!ASSERT_OK(err, "destroy_fentry")) > + goto cleanup; > + > + err = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.fentry_1), > &topts); > + if (!ASSERT_OK(err, "test_run_multi")) > + goto cleanup; > + ASSERT_EQ(skel->bss->test_result_fentry_1, 2, "multi_fentry_only"); > + ASSERT_EQ(skel->bss->test_result_fentry, 1, "fentry_detached"); > + > + err = bpf_link__destroy(multi_link); > + multi_link = NULL; > + if (!ASSERT_OK(err, "destroy_multi")) > + goto cleanup; > + > + err = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.fentry_1), > &topts); > + if (!ASSERT_OK(err, "test_run_detached")) > + goto cleanup; > + ASSERT_EQ(skel->bss->test_result_fentry_1, 2, "multi_fentry_detached"); > + ASSERT_EQ(skel->bss->test_result_fentry, 1, "fentry_still_detached"); > + > +cleanup: > + bpf_link__destroy(fentry_link); > + bpf_link__destroy(multi_link); > + free(ids); > + tracing_multi_intersect__destroy(skel); > +} > + > static void test_session(void) > { > LIBBPF_OPTS(bpf_test_run_opts, topts); > @@ -957,4 +1024,6 @@ void test_tracing_multi_test(void) > if (test__start_subtest("attach_api_fails")) > test_attach_api_fails(); > RUN_TESTS(tracing_multi_verifier); > + if (test__start_subtest("fentry_after_multi")) > + test_fentry_after_multi(); > } > diff --git > a/tools/testing/selftests/bpf/progs/tracing_multi_intersect_attach.c > b/tools/testing/selftests/bpf/progs/tracing_multi_intersect_attach.c > index cd5be0bb6ffd..5b0af8f4c62f 100644 > --- a/tools/testing/selftests/bpf/progs/tracing_multi_intersect_attach.c > +++ b/tools/testing/selftests/bpf/progs/tracing_multi_intersect_attach.c > @@ -11,6 +11,14 @@ __u64 test_result_fentry_1 = 0; > __u64 test_result_fentry_2 = 0; > __u64 test_result_fexit_1 = 0; > __u64 test_result_fexit_2 = 0; > +__u64 test_result_fentry = 0; > + > +SEC("fentry/bpf_fentry_test1") > +int BPF_PROG(fentry) > +{ > + tracing_multi_arg_check(ctx, &test_result_fentry, false); > + return 0; > +} > > SEC("fentry.multi") > int BPF_PROG(fentry_1) > -- > 2.55.0 >
