Commit d57293db authored by Jiri Olsa's avatar Jiri Olsa Committed by Andrii Nakryiko
Browse files

selftests/bpf: Add link info test for ref_ctr_offset retrieval 



Adding link info test for ref_ctr_offset retrieval for both
uprobe and uretprobe probes.

Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Acked-by: default avatarYafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/bpf/20250509153539.779599-3-jolsa@kernel.org
parent 82315333

tools/testing/selftests/bpf/prog_tests/fill_link_info.c

+16 −2
Original line number Diff line number Diff line
@@ -37,6 +37,7 @@ static noinline void uprobe_func(void) 
static int verify_perf_link_info(int fd, enum bpf_perf_event_type type, long addr,

				 ssize_t offset, ssize_t entry_offset)

{

	ssize_t ref_ctr_offset = entry_offset /* ref_ctr_offset for uprobes */;

	struct bpf_link_info info;

	__u32 len = sizeof(info);

	char buf[PATH_MAX];
@@ -97,6 +98,7 @@ static int verify_perf_link_info(int fd, enum bpf_perf_event_type type, long add 
	case BPF_PERF_EVENT_UPROBE:

	case BPF_PERF_EVENT_URETPROBE:

		ASSERT_EQ(info.perf_event.uprobe.offset, offset, "uprobe_offset");

		ASSERT_EQ(info.perf_event.uprobe.ref_ctr_offset, ref_ctr_offset, "uprobe_ref_ctr_offset");



		ASSERT_EQ(info.perf_event.uprobe.name_len, strlen(UPROBE_FILE) + 1,

				  "name_len");
@@ -241,20 +243,32 @@ static void test_uprobe_fill_link_info(struct test_fill_link_info *skel, 
		.retprobe = type == BPF_PERF_EVENT_URETPROBE,

		.bpf_cookie = PERF_EVENT_COOKIE,

	);

	const char *sema[1] = {

		"uprobe_link_info_sema_1",

	};

	__u64 *ref_ctr_offset;

	struct bpf_link *link;

	int link_fd, err;



	err = elf_resolve_syms_offsets("/proc/self/exe", 1, sema,

				       (unsigned long **) &ref_ctr_offset, STT_OBJECT);

	if (!ASSERT_OK(err, "elf_resolve_syms_offsets_object"))

		return;



	opts.ref_ctr_offset = *ref_ctr_offset;

	link = bpf_program__attach_uprobe_opts(skel->progs.uprobe_run,

					       0, /* self pid */

					       UPROBE_FILE, uprobe_offset,

					       &opts);

	if (!ASSERT_OK_PTR(link, "attach_uprobe"))

		return;

		goto out;



	link_fd = bpf_link__fd(link);

	err = verify_perf_link_info(link_fd, type, 0, uprobe_offset, 0);

	err = verify_perf_link_info(link_fd, type, 0, uprobe_offset, *ref_ctr_offset);

	ASSERT_OK(err, "verify_perf_link_info");

	bpf_link__destroy(link);

out:

	free(ref_ctr_offset);

}



static int verify_kmulti_link_info(int fd, bool retprobe, bool has_cookies)