selftests/bpf: Switch to ".bss"/".rodata"/".data" lookups for internal maps

mainline inclusion
from mainline-5.16-rc1
commit 4f2511e1
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5EUVD
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=4f2511e1990985103929ab799fb3ebca81969b77

-------------------------------------------------

Utilize libbpf's feature of allowing to lookup internal maps by their
ELF section names. No need to guess or calculate the exact truncated
prefix taken from the object name.
Signed-off-by: NAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211021014404.2635234-11-andrii@kernel.org
(cherry picked from commit 4f2511e1)
Signed-off-by: NWang Yufen <wangyufen@huawei.com>

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

@@ -164,7 +164,7 @@ void test_core_autosize(void)
 
 	usleep(1);
 
-	bss_map = bpf_object__find_map_by_name(skel->obj, "test_cor.bss");
+	bss_map = bpf_object__find_map_by_name(skel->obj, ".bss");
 	if (!ASSERT_OK_PTR(bss_map, "bss_map_find"))
 		goto cleanup;
 

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

@@ -877,7 +877,7 @@ void test_core_reloc(void)
 			goto cleanup;
 		}
 
-		data_map = bpf_object__find_map_by_name(obj, "test_cor.bss");
+		data_map = bpf_object__find_map_by_name(obj, ".bss");
 		if (CHECK(!data_map, "find_data_map", "data map not found\n"))
 			goto cleanup;
 

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

@@ -103,11 +103,18 @@ static void test_global_data_struct(struct bpf_object *obj, __u32 duration)
 static void test_global_data_rdonly(struct bpf_object *obj, __u32 duration)
 {
 	int err = -ENOMEM, map_fd, zero = 0;
-	struct bpf_map *map;
+	struct bpf_map *map, *map2;
 	__u8 *buff;
 
 	map = bpf_object__find_map_by_name(obj, "test_glo.rodata");
-	if (CHECK_FAIL(!map || !bpf_map__is_internal(map)))
+	if (!ASSERT_OK_PTR(map, "map"))
+		return;
+	if (!ASSERT_TRUE(bpf_map__is_internal(map), "is_internal"))
+		return;
+
+	/* ensure we can lookup internal maps by their ELF names */
+	map2 = bpf_object__find_map_by_name(obj, ".rodata");
+	if (!ASSERT_EQ(map, map2, "same_maps"))
 		return;
 
 	map_fd = bpf_map__fd(map);

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

@@ -16,7 +16,7 @@ void test_global_data_init(void)
 	if (CHECK_FAIL(err))
 		return;
 
-	map = bpf_object__find_map_by_name(obj, "test_glo.rodata");
+	map = bpf_object__find_map_by_name(obj, ".rodata");
 	if (CHECK_FAIL(!map || !bpf_map__is_internal(map)))
 		goto out;
 

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

@@ -92,7 +92,7 @@ void test_kfree_skb(void)
 	if (CHECK(!fexit, "find_prog", "prog eth_type_trans not found\n"))
 		goto close_prog;
 
-	global_data = bpf_object__find_map_by_name(obj2, "kfree_sk.bss");
+	global_data = bpf_object__find_map_by_name(obj2, ".bss");
 	if (CHECK(!global_data, "find global data", "not found\n"))
 		goto close_prog;
 

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

@@ -37,7 +37,7 @@ void test_rdonly_maps(void)
 	if (CHECK(err, "obj_load", "err %d errno %d\n", err, errno))
 		goto cleanup;
 
-	bss_map = bpf_object__find_map_by_name(obj, "test_rdo.bss");
+	bss_map = bpf_object__find_map_by_name(obj, ".bss");
 	if (CHECK(!bss_map, "find_bss_map", "failed\n"))
 		goto cleanup;