selftests/bpf: Add stacktrace ips test for fentry/fexit

Adding test that attaches fentry/fexitand verifies the
ORC stacktrace matches expected functions.

The test is only for ORC unwinder to keep it simple.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260126211837.472802-6-jolsa@kernel.org

diff --git a/tools/testing/selftests/bpf/prog_tests/stacktrace_ips.c b/tools/testing/selftests/bpf/prog_tests/stacktrace_ips.c
index 8528305361092ac4db595ad424d5cefd5fe224d9..da42b00e3d1fddac2bd195f11f52f322bcd5fffe 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/stacktrace_ips.c
+++ b/tools/testing/selftests/bpf/prog_tests/stacktrace_ips.c
@@ -183,6 +183,53 @@ cleanup:
        stacktrace_ips__destroy(skel);
 }
 
+static void test_stacktrace_ips_trampoline(bool retprobe)
+{
+       LIBBPF_OPTS(bpf_test_run_opts, topts);
+       struct stacktrace_ips *skel;
+
+       skel = stacktrace_ips__open_and_load();
+       if (!ASSERT_OK_PTR(skel, "stacktrace_ips__open_and_load"))
+               return;
+
+       if (!skel->kconfig->CONFIG_UNWINDER_ORC) {
+               test__skip();
+               goto cleanup;
+       }
+
+       if (retprobe) {
+               skel->links.fexit_test = bpf_program__attach_trace(skel->progs.fexit_test);
+               if (!ASSERT_OK_PTR(skel->links.fexit_test, "bpf_program__attach_trace"))
+                       goto cleanup;
+       } else {
+               skel->links.fentry_test = bpf_program__attach_trace(skel->progs.fentry_test);
+               if (!ASSERT_OK_PTR(skel->links.fentry_test, "bpf_program__attach_trace"))
+                       goto cleanup;
+       }
+
+       trigger_module_test_read(1);
+
+       load_kallsyms();
+
+       if (retprobe) {
+               check_stacktrace_ips(bpf_map__fd(skel->maps.stackmap), skel->bss->stack_key, 4,
+                                    ksym_get_addr("bpf_testmod_stacktrace_test_3"),
+                                    ksym_get_addr("bpf_testmod_stacktrace_test_2"),
+                                    ksym_get_addr("bpf_testmod_stacktrace_test_1"),
+                                    ksym_get_addr("bpf_testmod_test_read"));
+       } else {
+               check_stacktrace_ips(bpf_map__fd(skel->maps.stackmap), skel->bss->stack_key, 5,
+                                    ksym_get_addr("bpf_testmod_stacktrace_test"),
+                                    ksym_get_addr("bpf_testmod_stacktrace_test_3"),
+                                    ksym_get_addr("bpf_testmod_stacktrace_test_2"),
+                                    ksym_get_addr("bpf_testmod_stacktrace_test_1"),
+                                    ksym_get_addr("bpf_testmod_test_read"));
+       }
+
+cleanup:
+       stacktrace_ips__destroy(skel);
+}
+
 static void __test_stacktrace_ips(void)
 {
        if (test__start_subtest("kprobe_multi"))
@@ -195,6 +242,10 @@ static void __test_stacktrace_ips(void)
                test_stacktrace_ips_kprobe(false);
        if (test__start_subtest("kretprobe"))
                test_stacktrace_ips_kprobe(true);
+       if (test__start_subtest("fentry"))
+               test_stacktrace_ips_trampoline(false);
+       if (test__start_subtest("fexit"))
+               test_stacktrace_ips_trampoline(true);
 }
 #else
 static void __test_stacktrace_ips(void)

diff --git a/tools/testing/selftests/bpf/progs/stacktrace_ips.c b/tools/testing/selftests/bpf/progs/stacktrace_ips.c
index cae077a4061b100880314c4c5e19a93394da84c2..6830f29786130ae4e43c11c7f5fe44be3266cf4e 100644 (file)
--- a/tools/testing/selftests/bpf/progs/stacktrace_ips.c
+++ b/tools/testing/selftests/bpf/progs/stacktrace_ips.c
@@ -53,4 +53,24 @@ int rawtp_test(void *ctx)
        return 0;
 }
 
+SEC("fentry/bpf_testmod_stacktrace_test")
+int fentry_test(struct pt_regs *ctx)
+{
+       /*
+        * Skip 2 bpf_program/trampoline stack entries:
+        * - bpf_prog_bd1f7a949f55fb03_fentry_test
+        * - bpf_trampoline_182536277701
+        */
+       stack_key = bpf_get_stackid(ctx, &stackmap, 2);
+       return 0;
+}
+
+SEC("fexit/bpf_testmod_stacktrace_test")
+int fexit_test(struct pt_regs *ctx)
+{
+       /* Skip 2 bpf_program/trampoline stack entries, check fentry_test. */
+       stack_key = bpf_get_stackid(ctx, &stackmap, 2);
+       return 0;
+}
+
 char _license[] SEC("license") = "GPL";