selftests/bpf: Add post_connect_cb callback

For getting rid of the second parameter of do_test(), this patch adds a
new callback post_connect_cb in struct network_helper_opts, it will be
invoked after connect_fd_to_addr() in connect_to_fd_opts().

Then define a dctcp dedicated post_connect_cb callback, invoking
bpf_map_lookup_elem() in it, named stg_post_connect_cb() and set it in
test_dctcp().

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>

tools/testing/selftests/bpf/network_helpers.c

@@ -342,10 +342,14 @@ int connect_to_fd_opts(int server_fd, const struct network_helper_opts *opts)
 	    opts->post_socket_cb(fd, &opts->cb_opts))
 		goto error_close;
 
-	if (!opts->noconnect)
+	if (!opts->noconnect) {
 		if (connect_fd_to_addr(fd, &addr, addrlen, opts->must_fail))
 			goto error_close;
 
+		if (opts->post_connect_cb && opts->post_connect_cb(fd, &opts->cb_opts))
+			goto error_close;
+	}
+
 	return fd;
 
 error_close:

tools/testing/selftests/bpf/network_helpers.h

@@ -33,6 +33,7 @@ struct network_helper_opts {
 	int type;
 	int proto;
 	int (*post_socket_cb)(int fd, const struct post_socket_opts *opts);
+	int (*post_connect_cb)(int fd, const struct post_socket_opts *opts);
 	struct post_socket_opts cb_opts;
 };
 

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

@@ -33,13 +33,11 @@ static int settcpca(int fd, const char *tcp_ca)
 	return 0;
 }
 
-static void do_test(const struct network_helper_opts *opts,
-		    const struct bpf_map *sk_stg_map)
+static void do_test(const struct network_helper_opts *opts)
 {
 	struct sockaddr_storage addr;
 	int lfd = -1, fd = -1;
 	socklen_t addrlen;
-	int err;
 
 	if (make_sockaddr(AF_INET6, NULL, 0, &addr, &addrlen))
 		return;
@@ -53,16 +51,6 @@ static void do_test(const struct network_helper_opts *opts,
 	if (!ASSERT_NEQ(fd, -1, "connect_to_fd_opts"))
 		goto done;
 
-	if (sk_stg_map) {
-		int tmp_stg;
-
-		err = bpf_map_lookup_elem(bpf_map__fd(sk_stg_map), &fd,
-					  &tmp_stg);
-		if (!ASSERT_ERR(err, "bpf_map_lookup_elem(sk_stg_map)") ||
-				!ASSERT_EQ(errno, ENOENT, "bpf_map_lookup_elem(sk_stg_map)"))
-			goto done;
-	}
-
 	ASSERT_OK(send_recv_data(lfd, fd, total_bytes), "send_recv_data");
 
 done:
@@ -95,7 +83,7 @@ static void test_cubic(void)
 		return;
 	}
 
-	do_test(&opts, NULL);
+	do_test(&opts);
 
 	ASSERT_EQ(cubic_skel->bss->bpf_cubic_acked_called, 1, "pkts_acked called");
 
@@ -113,11 +101,24 @@ static int stg_post_socket_cb(int fd, const struct post_socket_opts *opts)
 	return bpf_map_update_elem(opts->map_fd, &fd, &expected_stg, BPF_NOEXIST);
 }
 
+static int stg_post_connect_cb(int fd, const struct post_socket_opts *opts)
+{
+	int tmp_stg;
+	int err;
+
+	err = bpf_map_lookup_elem(opts->map_fd, &fd, &tmp_stg);
+	if (!ASSERT_ERR(err, "bpf_map_lookup_elem(sk_stg_map)") ||
+			!ASSERT_EQ(errno, ENOENT, "bpf_map_lookup_elem(sk_stg_map)"))
+		return err;
+	return 0;
+}
+
 static void test_dctcp(void)
 {
 	struct network_helper_opts opts = {
 		.cb_opts.cc = "bpf_dctcp",
 		.post_socket_cb = stg_post_socket_cb,
+		.post_connect_cb = stg_post_connect_cb,
 	};
 	struct bpf_dctcp *dctcp_skel;
 	struct bpf_link *link;
@@ -133,7 +134,7 @@ static void test_dctcp(void)
 	}
 
 	opts.cb_opts.map_fd = bpf_map__fd(dctcp_skel->maps.sk_stg_map);
-	do_test(&opts, dctcp_skel->maps.sk_stg_map);
+	do_test(&opts);
 	ASSERT_EQ(dctcp_skel->bss->stg_result, expected_stg, "stg_result");
 
 	bpf_link__destroy(link);
@@ -328,14 +329,14 @@ static void test_update_ca(void)
 	link = bpf_map__attach_struct_ops(skel->maps.ca_update_1);
 	ASSERT_OK_PTR(link, "attach_struct_ops");
 
-	do_test(&opts, NULL);
+	do_test(&opts);
 	saved_ca1_cnt = skel->bss->ca1_cnt;
 	ASSERT_GT(saved_ca1_cnt, 0, "ca1_ca1_cnt");
 
 	err = bpf_link__update_map(link, skel->maps.ca_update_2);
 	ASSERT_OK(err, "update_map");
 
-	do_test(&opts, NULL);
+	do_test(&opts);
 	ASSERT_EQ(skel->bss->ca1_cnt, saved_ca1_cnt, "ca2_ca1_cnt");
 	ASSERT_GT(skel->bss->ca2_cnt, 0, "ca2_ca2_cnt");
 
@@ -361,14 +362,14 @@ static void test_update_wrong(void)
 	link = bpf_map__attach_struct_ops(skel->maps.ca_update_1);
 	ASSERT_OK_PTR(link, "attach_struct_ops");
 
-	do_test(&opts, NULL);
+	do_test(&opts);
 	saved_ca1_cnt = skel->bss->ca1_cnt;
 	ASSERT_GT(saved_ca1_cnt, 0, "ca1_ca1_cnt");
 
 	err = bpf_link__update_map(link, skel->maps.ca_wrong);
 	ASSERT_ERR(err, "update_map");
 
-	do_test(&opts, NULL);
+	do_test(&opts);
 	ASSERT_GT(skel->bss->ca1_cnt, saved_ca1_cnt, "ca2_ca1_cnt");
 
 	bpf_link__destroy(link);
@@ -395,7 +396,7 @@ static void test_mixed_links(void)
 	link = bpf_map__attach_struct_ops(skel->maps.ca_update_1);
 	ASSERT_OK_PTR(link, "attach_struct_ops");
 
-	do_test(&opts, NULL);
+	do_test(&opts);
 	ASSERT_GT(skel->bss->ca1_cnt, 0, "ca1_ca1_cnt");
 
 	err = bpf_link__update_map(link, skel->maps.ca_no_link);