1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * This times how long it takes to bind to a port when the port already
4  * has multiple sockets in its bhash table.
5  *
6  * In the setup(), we populate the port's bhash table with
7  * MAX_THREADS * MAX_CONNECTIONS number of entries.
8  */
9 
10 #include <unistd.h>
11 #include <stdio.h>
12 #include <netdb.h>
13 #include <pthread.h>
14 #include <string.h>
15 #include <stdbool.h>
16 
17 #define MAX_THREADS 600
18 #define MAX_CONNECTIONS 40
19 
20 static const char *setup_addr_v6 = "::1";
21 static const char *setup_addr_v4 = "127.0.0.1";
22 static const char *setup_addr;
23 static const char *bind_addr;
24 static const char *port;
25 bool use_v6;
26 int ret;
27 
28 static int fd_array[MAX_THREADS][MAX_CONNECTIONS];
29 
30 static int bind_socket(int opt, const char *addr)
31 {
32 	struct addrinfo *res, hint = {};
33 	int sock_fd, reuse = 1, err;
34 	int domain = use_v6 ? AF_INET6 : AF_INET;
35 
36 	sock_fd = socket(domain, SOCK_STREAM, 0);
37 	if (sock_fd < 0) {
38 		perror("socket fd err");
39 		return sock_fd;
40 	}
41 
42 	hint.ai_family = domain;
43 	hint.ai_socktype = SOCK_STREAM;
44 
45 	err = getaddrinfo(addr, port, &hint, &res);
46 	if (err) {
47 		perror("getaddrinfo failed");
48 		goto cleanup;
49 	}
50 
51 	if (opt) {
52 		err = setsockopt(sock_fd, SOL_SOCKET, opt, &reuse, sizeof(reuse));
53 		if (err) {
54 			perror("setsockopt failed");
55 			goto cleanup;
56 		}
57 	}
58 
59 	err = bind(sock_fd, res->ai_addr, res->ai_addrlen);
60 	if (err) {
61 		perror("failed to bind to port");
62 		goto cleanup;
63 	}
64 
65 	return sock_fd;
66 
67 cleanup:
68 	close(sock_fd);
69 	return err;
70 }
71 
72 static void *setup(void *arg)
73 {
74 	int sock_fd, i;
75 	int *array = (int *)arg;
76 
77 	for (i = 0; i < MAX_CONNECTIONS; i++) {
78 		sock_fd = bind_socket(SO_REUSEADDR | SO_REUSEPORT, setup_addr);
79 		if (sock_fd < 0) {
80 			ret = sock_fd;
81 			pthread_exit(&ret);
82 		}
83 		array[i] = sock_fd;
84 	}
85 
86 	return NULL;
87 }
88 
89 int main(int argc, const char *argv[])
90 {
91 	int listener_fd, sock_fd, i, j;
92 	pthread_t tid[MAX_THREADS];
93 	clock_t begin, end;
94 
95 	if (argc != 4) {
96 		printf("Usage: listener <port> <ipv6 | ipv4> <bind-addr>\n");
97 		return -1;
98 	}
99 
100 	port = argv[1];
101 	use_v6 = strcmp(argv[2], "ipv6") == 0;
102 	bind_addr = argv[3];
103 
104 	setup_addr = use_v6 ? setup_addr_v6 : setup_addr_v4;
105 
106 	listener_fd = bind_socket(SO_REUSEADDR | SO_REUSEPORT, setup_addr);
107 	if (listen(listener_fd, 100) < 0) {
108 		perror("listen failed");
109 		return -1;
110 	}
111 
112 	/* Set up threads to populate the bhash table entry for the port */
113 	for (i = 0; i < MAX_THREADS; i++)
114 		pthread_create(&tid[i], NULL, setup, fd_array[i]);
115 
116 	for (i = 0; i < MAX_THREADS; i++)
117 		pthread_join(tid[i], NULL);
118 
119 	if (ret)
120 		goto done;
121 
122 	begin = clock();
123 
124 	/* Bind to the same port on a different address */
125 	sock_fd  = bind_socket(0, bind_addr);
126 	if (sock_fd < 0)
127 		goto done;
128 
129 	end = clock();
130 
131 	printf("time spent = %f\n", (double)(end - begin) / CLOCKS_PER_SEC);
132 
133 	/* clean up */
134 	close(sock_fd);
135 
136 done:
137 	close(listener_fd);
138 	for (i = 0; i < MAX_THREADS; i++) {
139 		for (j = 0; i < MAX_THREADS; i++)
140 			close(fd_array[i][j]);
141 	}
142 
143 	return 0;
144 }
145