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]> --- .../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

