selftests/bpf: test_progs/sockopt_sk: Convert to use BPF skeleton

mainline inclusion
from mainline-5.13-rc1
commit cad99cce
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=cad99cce133dd5377f22da1e75d7eb5c4b886d75

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

Switch the test to use BPF skeleton to save some boilerplate and
make it easy to access bpf program bss segment.

The latter will be used to pass PAGE_SIZE from userspace since there
is no convenient way for bpf program to get it from inside of the
kernel.
Signed-off-by: NYauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: NAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210408061310.95877-2-yauheni.kaliuta@redhat.com
(cherry picked from commit cad99cce)
Signed-off-by: NWang Yufen <wangyufen@huawei.com>

Conflicts:
	tools/testing/selftests/bpf/prog_tests/sockopt_sk.c
Signed-off-by: NWang Yufen <wangyufen@huawei.com>

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

@@ -2,6 +2,8 @@
 #include <test_progs.h>
 #include "cgroup_helpers.h"
 
+#include "sockopt_sk.skel.h"
+
 #define SOL_CUSTOM			0xdeadbeef
 
 static int getsetsockopt(void)
@@ -163,60 +165,28 @@ static int getsetsockopt(void)
 	return -1;
 }
 
-static int prog_attach(struct bpf_object *obj, int cgroup_fd, const char *title)
-{
-	enum bpf_attach_type attach_type;
-	enum bpf_prog_type prog_type;
-	struct bpf_program *prog;
-	int err;
-
-	err = libbpf_prog_type_by_name(title, &prog_type, &attach_type);
-	if (err) {
-		log_err("Failed to deduct types for %s BPF program", title);
-		return -1;
-	}
-
-	prog = bpf_object__find_program_by_title(obj, title);
-	if (!prog) {
-		log_err("Failed to find %s BPF program", title);
-		return -1;
-	}
-
-	err = bpf_prog_attach(bpf_program__fd(prog), cgroup_fd,
-			      attach_type, 0);
-	if (err) {
-		log_err("Failed to attach %s BPF program", title);
-		return -1;
-	}
-
-	return 0;
-}
-
 static void run_test(int cgroup_fd)
 {
-	struct bpf_prog_load_attr attr = {
-		.file = "./sockopt_sk.o",
-	};
-	struct bpf_object *obj;
-	int ignored;
-	int err;
-
-	err = bpf_prog_load_xattr(&attr, &obj, &ignored);
-	if (CHECK_FAIL(err))
-		return;
+	struct sockopt_sk *skel;
+
+	skel = sockopt_sk__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "skel_load"))
+		goto cleanup;
 
-	err = prog_attach(obj, cgroup_fd, "cgroup/getsockopt");
-	if (CHECK_FAIL(err))
-		goto close_bpf_object;
+	skel->links._setsockopt =
+		bpf_program__attach_cgroup(skel->progs._setsockopt, cgroup_fd);
+	if (!ASSERT_OK_PTR(skel->links._setsockopt, "setsockopt_link"))
+		goto cleanup;
 
-	err = prog_attach(obj, cgroup_fd, "cgroup/setsockopt");
-	if (CHECK_FAIL(err))
-		goto close_bpf_object;
+	skel->links._getsockopt =
+		bpf_program__attach_cgroup(skel->progs._getsockopt, cgroup_fd);
+	if (!ASSERT_OK_PTR(skel->links._getsockopt, "getsockopt_link"))
+		goto cleanup;
 
-	CHECK_FAIL(getsetsockopt());
+	ASSERT_OK(getsetsockopt(), "getsetsockopt");
 
-close_bpf_object:
-	bpf_object__close(obj);
+cleanup:
+	sockopt_sk__destroy(skel);
 }
 
 void test_sockopt_sk(void)