selftests/bpf: Use non-autoloaded programs in few tests

Take advantage of new libbpf feature for declarative non-autoloaded BPF
program SEC() definitions in few test that test single program at a time
out of many available programs within the single BPF object.

Signed-off-by: Andrii Nakryiko <[e-mail]>
Signed-off-by: Alexei Starovoitov <[e-mail]>
Link: https://lore.kernel.org/bpf/[e-mail]

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

···
 void test_helper_restricted(void)
 {
 	int prog_i = 0, prog_cnt;
-	int duration = 0;
 
 	do {
 		struct test_helper_restricted *test;
-		int maybeOK;
+		int err;
 
 		test = test_helper_restricted__open();
 		if (!ASSERT_OK_PTR(test, "open"))
···
 		for (int j = 0; j < prog_cnt; ++j) {
 			struct bpf_program *prog = *test->skeleton->progs[j].prog;
 
-			maybeOK = bpf_program__set_autoload(prog, prog_i == j);
-			ASSERT_OK(maybeOK, "set autoload");
+			bpf_program__set_autoload(prog, true);
 		}
 
-		maybeOK = test_helper_restricted__load(test);
-		CHECK(!maybeOK, test->skeleton->progs[prog_i].name, "helper isn't restricted");
+		err = test_helper_restricted__load(test);
+		ASSERT_ERR(err, "load_should_fail");
 
 		test_helper_restricted__destroy(test);
 	} while (++prog_i < prog_cnt);

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

···
 // SPDX-License-Identifier: GPL-2.0
 #include <test_progs.h>
 
-static void toggle_object_autoload_progs(const struct bpf_object *obj,
-					 const char *name_load)
-{
-	struct bpf_program *prog;
-
-	bpf_object__for_each_program(prog, obj) {
-		const char *name = bpf_program__name(prog);
-
-		if (!strcmp(name_load, name))
-			bpf_program__set_autoload(prog, true);
-		else
-			bpf_program__set_autoload(prog, false);
-	}
-}
-
 void test_reference_tracking(void)
 {
 	const char *file = "test_sk_lookup_kern.o";
···
 		goto cleanup;
 
 	bpf_object__for_each_program(prog, obj_iter) {
+		struct bpf_program *p;
 		const char *name;
 
 		name = bpf_program__name(prog);
···
 		if (!ASSERT_OK_PTR(obj, "obj_open_file"))
 			goto cleanup;
 
-		toggle_object_autoload_progs(obj, name);
+		/* all programs are not loaded by default, so just set
+		 * autoload to true for the single prog under test
+		 */
+		p = bpf_object__find_program_by_name(obj, name);
+		bpf_program__set_autoload(p, true);
+
 		/* Expect verifier failure if test name has 'err' */
 		if (strncmp(name, "err_", sizeof("err_") - 1) == 0) {
 			libbpf_print_fn_t old_print_fn;

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

···
 static void test_strncmp_ret(void)
 {
 	struct strncmp_test *skel;
-	struct bpf_program *prog;
 	int err, got;
 
 	skel = strncmp_test__open();
 	if (!ASSERT_OK_PTR(skel, "strncmp_test open"))
 		return;
-
-	bpf_object__for_each_program(prog, skel->obj)
-		bpf_program__set_autoload(prog, false);
 
 	bpf_program__set_autoload(skel->progs.do_strncmp, true);
 
···
 static void test_strncmp_bad_not_const_str_size(void)
 {
 	struct strncmp_test *skel;
-	struct bpf_program *prog;
 	int err;
 
 	skel = strncmp_test__open();
 	if (!ASSERT_OK_PTR(skel, "strncmp_test open"))
 		return;
 
-	bpf_object__for_each_program(prog, skel->obj)
-		bpf_program__set_autoload(prog, false);
-
-	bpf_program__set_autoload(skel->progs.strncmp_bad_not_const_str_size,
-				  true);
+	bpf_program__set_autoload(skel->progs.strncmp_bad_not_const_str_size, true);
 
 	err = strncmp_test__load(skel);
 	ASSERT_ERR(err, "strncmp_test load bad_not_const_str_size");
···
 static void test_strncmp_bad_writable_target(void)
 {
 	struct strncmp_test *skel;
-	struct bpf_program *prog;
 	int err;
 
 	skel = strncmp_test__open();
 	if (!ASSERT_OK_PTR(skel, "strncmp_test open"))
 		return;
 
-	bpf_object__for_each_program(prog, skel->obj)
-		bpf_program__set_autoload(prog, false);
-
-	bpf_program__set_autoload(skel->progs.strncmp_bad_writable_target,
-				  true);
+	bpf_program__set_autoload(skel->progs.strncmp_bad_writable_target, true);
 
 	err = strncmp_test__load(skel);
 	ASSERT_ERR(err, "strncmp_test load bad_writable_target");
···
 static void test_strncmp_bad_not_null_term_target(void)
 {
 	struct strncmp_test *skel;
-	struct bpf_program *prog;
 	int err;
 
 	skel = strncmp_test__open();
 	if (!ASSERT_OK_PTR(skel, "strncmp_test open"))
 		return;
 
-	bpf_object__for_each_program(prog, skel->obj)
-		bpf_program__set_autoload(prog, false);
-
-	bpf_program__set_autoload(skel->progs.strncmp_bad_not_null_term_target,
-				  true);
+	bpf_program__set_autoload(skel->progs.strncmp_bad_not_null_term_target, true);
 
 	err = strncmp_test__load(skel);
 	ASSERT_ERR(err, "strncmp_test load bad_not_null_term_target");

tools/testing/selftests/bpf/progs/strncmp_test.c

···
 
 char _license[] SEC("license") = "GPL";
 
-SEC("tp/syscalls/sys_enter_nanosleep")
+SEC("?tp/syscalls/sys_enter_nanosleep")
 int do_strncmp(void *ctx)
 {
 	if ((bpf_get_current_pid_tgid() >> 32) != target_pid)
···
 	return 0;
 }
 
-SEC("tp/syscalls/sys_enter_nanosleep")
+SEC("?tp/syscalls/sys_enter_nanosleep")
 int strncmp_bad_not_const_str_size(void *ctx)
 {
 	/* The value of string size is not const, so will fail */
···
 	return 0;
 }
 
-SEC("tp/syscalls/sys_enter_nanosleep")
+SEC("?tp/syscalls/sys_enter_nanosleep")
 int strncmp_bad_writable_target(void *ctx)
 {
 	/* Compared target is not read-only, so will fail */
···
 	return 0;
 }
 
-SEC("tp/syscalls/sys_enter_nanosleep")
+SEC("?tp/syscalls/sys_enter_nanosleep")
 int strncmp_bad_not_null_term_target(void *ctx)
 {
 	/* Compared target is not null-terminated, so will fail */

tools/testing/selftests/bpf/progs/test_helper_restricted.c

···
 	}
 }
 
-SEC("raw_tp/sys_enter")
+SEC("?raw_tp/sys_enter")
 int raw_tp_timer(void *ctx)
 {
 	timer_work();
···
 	return 0;
 }
 
-SEC("tp/syscalls/sys_enter_nanosleep")
+SEC("?tp/syscalls/sys_enter_nanosleep")
 int tp_timer(void *ctx)
 {
 	timer_work();
···
 	return 0;
 }
 
-SEC("kprobe/sys_nanosleep")
+SEC("?kprobe/sys_nanosleep")
 int kprobe_timer(void *ctx)
 {
 	timer_work();
···
 	return 0;
 }
 
-SEC("perf_event")
+SEC("?perf_event")
 int perf_event_timer(void *ctx)
 {
 	timer_work();
···
 	return 0;
 }
 
-SEC("raw_tp/sys_enter")
+SEC("?raw_tp/sys_enter")
 int raw_tp_spin_lock(void *ctx)
 {
 	spin_lock_work();
···
 	return 0;
 }
 
-SEC("tp/syscalls/sys_enter_nanosleep")
+SEC("?tp/syscalls/sys_enter_nanosleep")
 int tp_spin_lock(void *ctx)
 {
 	spin_lock_work();
···
 	return 0;
 }
 
-SEC("kprobe/sys_nanosleep")
+SEC("?kprobe/sys_nanosleep")
 int kprobe_spin_lock(void *ctx)
 {
 	spin_lock_work();
···
 	return 0;
 }
 
-SEC("perf_event")
+SEC("?perf_event")
 int perf_event_spin_lock(void *ctx)
 {
 	spin_lock_work();

tools/testing/selftests/bpf/progs/test_sk_lookup_kern.c

···
 	return result;
 }
 
-SEC("tc")
+SEC("?tc")
 int sk_lookup_success(struct __sk_buff *skb)
 {
 	void *data_end = (void *)(long)skb->data_end;
···
 	return sk ? TC_ACT_OK : TC_ACT_UNSPEC;
 }
 
-SEC("tc")
+SEC("?tc")
 int sk_lookup_success_simple(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
···
 	return 0;
 }
 
-SEC("tc")
+SEC("?tc")
 int err_use_after_free(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
···
 	return family;
 }
 
-SEC("tc")
+SEC("?tc")
 int err_modify_sk_pointer(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
···
 	return 0;
 }
 
-SEC("tc")
+SEC("?tc")
 int err_modify_sk_or_null_pointer(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
···
 	return 0;
 }
 
-SEC("tc")
+SEC("?tc")
 int err_no_release(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
···
 	return 0;
 }
 
-SEC("tc")
+SEC("?tc")
 int err_release_twice(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
···
 	return 0;
 }
 
-SEC("tc")
+SEC("?tc")
 int err_release_unchecked(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
···
 	bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), BPF_F_CURRENT_NETNS, 0);
 }
 
-SEC("tc")
+SEC("?tc")
 int err_no_release_subcall(struct __sk_buff *skb)
 {
 	lookup_no_release(skb);