selftests/bpf: Propagate errors during setup for reuseport tests

Prepare for switching reuseport tests to test_progs framework, where we
don't have the luxury to terminate the process on failure.

Modify setup helpers to signal failure via the return value with the help
of a macro similar to the one currently in use by the tests.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191212102259.418536-8-jakub@cloudflare.com

tools/testing/selftests/bpf/test_select_reuseport.c

@@ -32,7 +32,7 @@
 static int result_map, tmp_index_ovr_map, linum_map, data_check_map;
 static enum result expected_results[NR_RESULTS];
 static int sk_fds[REUSEPORT_ARRAY_SIZE];
-static int reuseport_array, outer_map;
+static int reuseport_array = -1, outer_map = -1;
 static int select_by_skb_data_prog;
 static int saved_tcp_syncookie;
 static struct bpf_object *obj;
@@ -55,7 +55,16 @@ static union sa46 {
 	}								\
 })
 
-static void create_maps(void)
+#define RET_ERR(condition, tag, format...) ({				\
+	int __ret = !!(condition);					\
+	if (__ret) {							\
+		printf("%s(%d):FAIL:%s ", __func__, __LINE__, tag);	\
+		printf(format);						\
+		return -1;						\
+	}								\
+})
+
+static int create_maps(void)
 {
 	struct bpf_create_map_attr attr = {};
 
@@ -67,7 +76,7 @@ static void create_maps(void)
 	attr.max_entries = REUSEPORT_ARRAY_SIZE;
 
 	reuseport_array = bpf_create_map_xattr(&attr);
-	CHECK(reuseport_array == -1, "creating reuseport_array",
+	RET_ERR(reuseport_array == -1, "creating reuseport_array",
 		"reuseport_array:%d errno:%d\n", reuseport_array, errno);
 
 	/* Creating outer_map */
@@ -78,57 +87,61 @@ static void create_maps(void)
 	attr.max_entries = 1;
 	attr.inner_map_fd = reuseport_array;
 	outer_map = bpf_create_map_xattr(&attr);
-	CHECK(outer_map == -1, "creating outer_map",
+	RET_ERR(outer_map == -1, "creating outer_map",
 		"outer_map:%d errno:%d\n", outer_map, errno);
+
+	return 0;
 }
 
-static void prepare_bpf_obj(void)
+static int prepare_bpf_obj(void)
 {
 	struct bpf_program *prog;
 	struct bpf_map *map;
 	int err;
 
 	obj = bpf_object__open("test_select_reuseport_kern.o");
-	CHECK(IS_ERR_OR_NULL(obj), "open test_select_reuseport_kern.o",
+	RET_ERR(IS_ERR_OR_NULL(obj), "open test_select_reuseport_kern.o",
 		"obj:%p PTR_ERR(obj):%ld\n", obj, PTR_ERR(obj));
 
 	map = bpf_object__find_map_by_name(obj, "outer_map");
-	CHECK(!map, "find outer_map", "!map\n");
+	RET_ERR(!map, "find outer_map", "!map\n");
 	err = bpf_map__reuse_fd(map, outer_map);
-	CHECK(err, "reuse outer_map", "err:%d\n", err);
+	RET_ERR(err, "reuse outer_map", "err:%d\n", err);
 
 	err = bpf_object__load(obj);
-	CHECK(err, "load bpf_object", "err:%d\n", err);
+	RET_ERR(err, "load bpf_object", "err:%d\n", err);
 
 	prog = bpf_program__next(NULL, obj);
-	CHECK(!prog, "get first bpf_program", "!prog\n");
+	RET_ERR(!prog, "get first bpf_program", "!prog\n");
 	select_by_skb_data_prog = bpf_program__fd(prog);
-	CHECK(select_by_skb_data_prog == -1, "get prog fd",
+	RET_ERR(select_by_skb_data_prog == -1, "get prog fd",
 		"select_by_skb_data_prog:%d\n", select_by_skb_data_prog);
 
 	map = bpf_object__find_map_by_name(obj, "result_map");
-	CHECK(!map, "find result_map", "!map\n");
+	RET_ERR(!map, "find result_map", "!map\n");
 	result_map = bpf_map__fd(map);
-	CHECK(result_map == -1, "get result_map fd",
+	RET_ERR(result_map == -1, "get result_map fd",
 		"result_map:%d\n", result_map);
 
 	map = bpf_object__find_map_by_name(obj, "tmp_index_ovr_map");
-	CHECK(!map, "find tmp_index_ovr_map", "!map\n");
+	RET_ERR(!map, "find tmp_index_ovr_map\n", "!map");
 	tmp_index_ovr_map = bpf_map__fd(map);
-	CHECK(tmp_index_ovr_map == -1, "get tmp_index_ovr_map fd",
+	RET_ERR(tmp_index_ovr_map == -1, "get tmp_index_ovr_map fd",
 		"tmp_index_ovr_map:%d\n", tmp_index_ovr_map);
 
 	map = bpf_object__find_map_by_name(obj, "linum_map");
-	CHECK(!map, "find linum_map", "!map\n");
+	RET_ERR(!map, "find linum_map", "!map\n");
 	linum_map = bpf_map__fd(map);
-	CHECK(linum_map == -1, "get linum_map fd",
+	RET_ERR(linum_map == -1, "get linum_map fd",
 		"linum_map:%d\n", linum_map);
 
 	map = bpf_object__find_map_by_name(obj, "data_check_map");
-	CHECK(!map, "find data_check_map", "!map\n");
+	RET_ERR(!map, "find data_check_map", "!map\n");
 	data_check_map = bpf_map__fd(map);
-	CHECK(data_check_map == -1, "get data_check_map fd",
+	RET_ERR(data_check_map == -1, "get data_check_map fd",
 		"data_check_map:%d\n", data_check_map);
+
+	return 0;
 }
 
 static void sa46_init_loopback(union sa46 *sa, sa_family_t family)
@@ -157,31 +170,34 @@ static int read_int_sysctl(const char *sysctl)
 	int fd, ret;
 
 	fd = open(sysctl, 0);
-	CHECK(fd == -1, "open(sysctl)", "sysctl:%s fd:%d errno:%d\n",
-	      sysctl, fd, errno);
+	RET_ERR(fd == -1, "open(sysctl)",
+		"sysctl:%s fd:%d errno:%d\n", sysctl, fd, errno);
 
 	ret = read(fd, buf, sizeof(buf));
-	CHECK(ret <= 0, "read(sysctl)", "sysctl:%s ret:%d errno:%d\n",
-	      sysctl, ret, errno);
-	close(fd);
+	RET_ERR(ret <= 0, "read(sysctl)",
+		"sysctl:%s ret:%d errno:%d\n", sysctl, ret, errno);
 
+	close(fd);
 	return atoi(buf);
 }
 
-static void write_int_sysctl(const char *sysctl, int v)
+static int write_int_sysctl(const char *sysctl, int v)
 {
 	int fd, ret, size;
 	char buf[16];
 
 	fd = open(sysctl, O_RDWR);
-	CHECK(fd == -1, "open(sysctl)", "sysctl:%s fd:%d errno:%d\n",
-	      sysctl, fd, errno);
+	RET_ERR(fd == -1, "open(sysctl)",
+		"sysctl:%s fd:%d errno:%d\n", sysctl, fd, errno);
 
 	size = snprintf(buf, sizeof(buf), "%d", v);
 	ret = write(fd, buf, size);
-	CHECK(ret != size, "write(sysctl)",
-	      "sysctl:%s ret:%d size:%d errno:%d\n", sysctl, ret, size, errno);
+	RET_ERR(ret != size, "write(sysctl)",
+		"sysctl:%s ret:%d size:%d errno:%d\n",
+		sysctl, ret, size, errno);
+
 	close(fd);
+	return 0;
 }
 
 static void restore_sysctls(void)
@@ -190,22 +206,25 @@ static void restore_sysctls(void)
 	write_int_sysctl(TCP_SYNCOOKIE_SYSCTL, saved_tcp_syncookie);
 }
 
-static void enable_fastopen(void)
+static int enable_fastopen(void)
 {
 	int fo;
 
 	fo = read_int_sysctl(TCP_FO_SYSCTL);
-	write_int_sysctl(TCP_FO_SYSCTL, fo | 7);
+	if (fo < 0)
+		return -1;
+
+	return write_int_sysctl(TCP_FO_SYSCTL, fo | 7);
 }
 
-static void enable_syncookie(void)
+static int enable_syncookie(void)
 {
-	write_int_sysctl(TCP_SYNCOOKIE_SYSCTL, 2);
+	return write_int_sysctl(TCP_SYNCOOKIE_SYSCTL, 2);
 }
 
-static void disable_syncookie(void)
+static int disable_syncookie(void)
 {
-	write_int_sysctl(TCP_SYNCOOKIE_SYSCTL, 0);
+	return write_int_sysctl(TCP_SYNCOOKIE_SYSCTL, 0);
 }
 
 static __u32 get_linum(void)
@@ -683,8 +702,11 @@ static void cleanup_per_test(bool no_inner_map)
 
 static void cleanup(void)
 {
+	if (outer_map != -1)
 		close(outer_map);
+	if (reuseport_array != -1)
 		close(reuseport_array);
+	if (obj)
 		bpf_object__close(obj);
 }
 
@@ -765,16 +787,28 @@ static void test_all(void)
 
 int main(int argc, const char **argv)
 {
-	create_maps();
-	prepare_bpf_obj();
+	int ret = EXIT_FAILURE;
+
+	if (create_maps())
+		goto out;
+	if (prepare_bpf_obj())
+		goto out;
+
 	saved_tcp_fo = read_int_sysctl(TCP_FO_SYSCTL);
 	saved_tcp_syncookie = read_int_sysctl(TCP_SYNCOOKIE_SYSCTL);
-	enable_fastopen();
-	disable_syncookie();
+	if (saved_tcp_syncookie < 0 || saved_tcp_syncookie < 0)
+		goto out;
 	atexit(restore_sysctls);
 
+	if (enable_fastopen())
+		goto out;
+	if (disable_syncookie())
+		goto out;
+
 	test_all();
 
+	ret = EXIT_SUCCESS;
+out:
 	cleanup();
-	return 0;
+	return ret;
 }