1 /*	$NetBSD: bench_cascade.c,v 1.5 2020/05/25 20:47:34 christos Exp $	*/
2 
3 /*
4  * Copyright 2007-2012 Niels Provos and Nick Mathewson
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 4. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  *
28  */
29 
30 #include "event2/event-config.h"
31 
32 #include <sys/types.h>
33 #include <sys/stat.h>
34 #ifdef EVENT__HAVE_SYS_TIME_H
35 #include <sys/time.h>
36 #endif
37 #ifdef _WIN32
38 #define WIN32_LEAN_AND_MEAN
39 #include <windows.h>
40 #else
41 #include <sys/socket.h>
42 #include <sys/resource.h>
43 #endif
44 #include <signal.h>
45 #include <fcntl.h>
46 #include <stdlib.h>
47 #include <stdio.h>
48 #include <string.h>
49 #ifdef EVENT__HAVE_UNISTD_H
50 #include <unistd.h>
51 #endif
52 #include <errno.h>
53 #include <getopt.h>
54 #include <event.h>
55 #include <evutil.h>
56 
57 /*
58  * This benchmark tests how quickly we can propagate a write down a chain
59  * of socket pairs.  We start by writing to the first socket pair and all
60  * events will fire subsequently until the last socket pair has been reached
61  * and the benchmark terminates.
62  */
63 
64 static int fired;
65 static evutil_socket_t *pipes;
66 static struct event *events;
67 
68 static void
read_cb(evutil_socket_t fd,short which,void * arg)69 read_cb(evutil_socket_t fd, short which, void *arg)
70 {
71 	char ch;
72 	evutil_socket_t sock = (evutil_socket_t)(ev_intptr_t)arg;
73 
74 	(void) recv(fd, &ch, sizeof(ch), 0);
75 	if (sock >= 0) {
76 		if (send(sock, "e", 1, 0) < 0)
77 			perror("send");
78 	}
79 	fired++;
80 }
81 
82 static struct timeval *
run_once(int num_pipes)83 run_once(int num_pipes)
84 {
85 	int i;
86 	evutil_socket_t *cp;
87 	static struct timeval ts, te, tv_timeout;
88 
89 	events = (struct event *)calloc(num_pipes, sizeof(struct event));
90 	pipes = (evutil_socket_t *)calloc(num_pipes * 2, sizeof(evutil_socket_t));
91 
92 	if (events == NULL || pipes == NULL) {
93 		perror("malloc");
94 		exit(1);
95 	}
96 
97 	for (cp = pipes, i = 0; i < num_pipes; i++, cp += 2) {
98 		if (evutil_socketpair(AF_UNIX, SOCK_STREAM, 0, cp) == -1) {
99 			perror("socketpair");
100 			exit(1);
101 		}
102 	}
103 
104 	/* measurements includes event setup */
105 	evutil_gettimeofday(&ts, NULL);
106 
107 	/* provide a default timeout for events */
108 	evutil_timerclear(&tv_timeout);
109 	tv_timeout.tv_sec = 60;
110 
111 	for (cp = pipes, i = 0; i < num_pipes; i++, cp += 2) {
112 		evutil_socket_t fd = i < num_pipes - 1 ? cp[3] : -1;
113 		event_set(&events[i], cp[0], EV_READ, read_cb,
114 		    (void *)(ev_intptr_t)fd);
115 		event_add(&events[i], &tv_timeout);
116 	}
117 
118 	fired = 0;
119 
120 	/* kick everything off with a single write */
121 	if (send(pipes[1], "e", 1, 0) < 0)
122 		perror("send");
123 
124 	event_dispatch();
125 
126 	evutil_gettimeofday(&te, NULL);
127 	evutil_timersub(&te, &ts, &te);
128 
129 	for (cp = pipes, i = 0; i < num_pipes; i++, cp += 2) {
130 		event_del(&events[i]);
131 		evutil_closesocket(cp[0]);
132 		evutil_closesocket(cp[1]);
133 	}
134 
135 	free(pipes);
136 	free(events);
137 
138 	return (&te);
139 }
140 
141 int
main(int argc,char ** argv)142 main(int argc, char **argv)
143 {
144 #ifdef HAVE_SETRLIMIT
145 	struct rlimit rl;
146 #endif
147 	int i, c;
148 	struct timeval *tv;
149 
150 	int num_pipes = 100;
151 #ifdef _WIN32
152 	WSADATA WSAData;
153 	WSAStartup(0x101, &WSAData);
154 #endif
155 
156 	while ((c = getopt(argc, argv, "n:")) != -1) {
157 		switch (c) {
158 		case 'n':
159 			num_pipes = atoi(optarg);
160 			break;
161 		default:
162 			fprintf(stderr, "Illegal argument \"%c\"\n", c);
163 			exit(1);
164 		}
165 	}
166 
167 #ifdef HAVE_SETRLIMIT
168 	rl.rlim_cur = rl.rlim_max = num_pipes * 2 + 50;
169 	if (setrlimit(RLIMIT_NOFILE, &rl) == -1) {
170 		perror("setrlimit");
171 		exit(1);
172 	}
173 #endif
174 
175 	event_init();
176 
177 	for (i = 0; i < 25; i++) {
178 		tv = run_once(num_pipes);
179 		if (tv == NULL)
180 			exit(1);
181 		fprintf(stdout, "%ld\n",
182 			tv->tv_sec * 1000000L + tv->tv_usec);
183 	}
184 
185 #ifdef _WIN32
186 	WSACleanup();
187 #endif
188 
189 	exit(0);
190 }
191