Merge branch 'libbpf: error reporting changes for v1.0'

Andrii Nakryiko says:

====================

Implement error reporting changes discussed in "Libbpf: the road to v1.0"
([0]) document.

Libbpf gets a new API, libbpf_set_strict_mode() which accepts a set of flags
that turn on a set of libbpf 1.0 changes, that might be potentially breaking.
It's possible to opt-in into all current and future 1.0 features by specifying
LIBBPF_STRICT_ALL flag.

When some of the 1.0 "features" are requested, libbpf APIs might behave
differently. In this patch set a first set of changes are implemented, all
related to the way libbpf returns errors. See individual patches for details.

Patch #1 adds a no-op libbpf_set_strict_mode() functionality to enable
updating selftests.

Patch #2 gets rid of all the bad code patterns that will break in libbpf 1.0
(exact -1 comparison for low-level APIs, direct IS_ERR() macro usage to check
pointer-returning APIs for error, etc). These changes make selftest work in
both legacy and 1.0 libbpf modes. Selftests also opt-in into 100% libbpf 1.0
mode to automatically gain all the subsequent changes, which will come in
follow up patches.

Patch #3 streamlines error reporting for low-level APIs wrapping bpf() syscall.

Patch #4 streamlines errors for all the rest APIs.

Patch #5 ensures that BPF skeletons propagate errors properly as well, as
currently on error some APIs will return NULL with no way of checking exact
error code.

  [0] https://docs.google.com/document/d/1UyjTZuPFWiPFyKk1tV5an11_iaRuec6U-ZESZ54nNTY

v1->v2:
  - move libbpf_set_strict_mode() implementation to patch #1, where it belongs
    (Alexei);
  - add acks, slight rewording of commit messages.
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 4 insertions, 4 deletions

diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
index ab77596b64e3..1352ec104149 100644
--- a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
+++ b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
@@ -88,11 +88,11 @@ static void test_sockmap_create_update_free(enum bpf_map_type map_type)
 	int s, map, err;
 
 	s = connected_socket_v4();
-	if (CHECK_FAIL(s == -1))
+	if (CHECK_FAIL(s < 0))
 		return;
 
 	map = bpf_create_map(map_type, sizeof(int), sizeof(int), 1, 0);
-	if (CHECK_FAIL(map == -1)) {
+	if (CHECK_FAIL(map < 0)) {
 		perror("bpf_create_map");
 		goto out;
 	}
@@ -245,7 +245,7 @@ static void test_sockmap_copy(enum bpf_map_type map_type)
 	opts.link_info = &linfo;
 	opts.link_info_len = sizeof(linfo);
 	link = bpf_program__attach_iter(skel->progs.copy, &opts);
-	if (CHECK(IS_ERR(link), "attach_iter", "attach_iter failed\n"))
+	if (!ASSERT_OK_PTR(link, "attach_iter"))
 		goto out;
 
 	iter_fd = bpf_iter_create(bpf_link__fd(link));
@@ -304,7 +304,7 @@ static void test_sockmap_skb_verdict_attach(enum bpf_attach_type first,
 	}
 
 	err = bpf_prog_attach(verdict, map, second, 0);
-	assert(err == -1 && errno == EBUSY);
+	ASSERT_EQ(err, -EBUSY, "prog_attach_fail");
 
 	err = bpf_prog_detach2(verdict, map, first);
 	if (CHECK_FAIL(err)) {