1 /*
2 * TUXLOAD.C
3 *
4 * (c)Copyright 2012 Antonio Huete Jimenez <tuxillo@quantumachine.net>,
5 * this code is hereby placed in the public domain.
6 *
7 * As a safety the directory 'tmpfiles/' must exist. This program will
8 * create 500 x 8MB files in tmpfiles/*, memory map the files MAP_SHARED,
9 * R+W, make random modifications, and msync() in a loop.
10 *
11 * The purpose is to stress the VM system.
12 *
13 */
14 #include <stdio.h>
15 #include <unistd.h>
16 #include <fcntl.h>
17 #include <stdlib.h>
18 #include <sys/mman.h>
19 #include <sys/stat.h>
20 #include <err.h>
21 #include <errno.h>
22
23 static void randomfill(int fd);
24 static int mmap01(void *);
25 static int mmap02(void *);
26 static int build_files(void);
27
28 int opt_verbose;
29 int opt_testno;
30 int opt_nofiles;
31 int opt_mbfile;
32 int opt_count;
33 int fliparg;
34
35 int *fd;
36 struct stat *st;
37 char **pp;
38
39 static const struct test {
40 char testdesc[128];
41 int (*testfn)(void *);
42 } testlist[] = {
43 { "mmap01 - Massive mmap / msync (flushing all pages)", mmap01 },
44 { "mmap02 - Massive mmap / msync (flushing only specified pages)", mmap02 },
45 { "", NULL }
46 };
47
48 static int
mmap01(void * arg)49 mmap01(void *arg)
50 {
51 int i;
52 int *bug = arg;
53 long jump;
54 size_t size, len;
55
56 if ((build_files()) != 0)
57 err(1, "Failed to create the files");
58
59 if (opt_verbose)
60 printf("\n");
61
62 for (i = 0; i < opt_nofiles; i++) {
63
64 if (opt_verbose) {
65 fflush(stdout);
66 fprintf(stdout, "\rDoing mmap() + msync() [%d/%d] ", i+1, opt_nofiles);
67 }
68 size = st[i].st_size;
69 pp[i] = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd[i], 0);
70 if (pp[i] == MAP_FAILED)
71 err(1, "mmap");
72
73 for (jump = 0; jump < size; jump += 65535) {
74 pp[i][jump] = jump + i;
75 }
76
77 if (fliparg)
78 len = MS_SYNC;
79 else
80 len = 0;
81
82 if ((msync(pp[i], len, MS_SYNC)) == -1) {
83 printf("fd %d %p\n", fd[i], pp[i]);
84 err(1, "msync");
85
86 }
87 }
88 printf("\n");
89
90 return 0;
91 }
92
93 static int
mmap02(void * arg)94 mmap02(void *arg)
95 {
96 fliparg = 1;
97 mmap01(&fliparg);
98
99 return 0;
100 }
101
102 static void
usage(void)103 usage(void)
104 {
105 int i;
106 const struct test *tp;
107
108 printf("tuxload: [-v] [-c count] [-m megs_per_file] [-n no_of_files] [-t test_to_run] \n"
109 "Available tests: \n");
110
111 for (tp = testlist; tp->testfn != NULL; tp++)
112 printf("\t%s\n", tp->testdesc);
113 exit(1);
114 }
115
116 int
main(int argc,char * argv[])117 main(int argc, char *argv[])
118 {
119 int forever;
120 char c;
121
122 opt_verbose = opt_testno = 0;
123 opt_nofiles = 500;
124 opt_mbfile = 8;
125 opt_count = 1;
126 fliparg = 0;
127 forever = 0;
128
129 while ((c = getopt(argc, argv, "n:t:m:c:v")) != -1) {
130 switch(c) {
131 case 'v':
132 opt_verbose++;
133 break;
134 case 'n':
135 opt_nofiles = (int)strtol(optarg, NULL, 0);
136 break;
137 case 't':
138 opt_testno = (int)strtol(optarg, NULL, 0);
139 opt_testno--;
140 break;
141 case 'm':
142 opt_mbfile = (int)strtol(optarg, NULL, 0);
143 break;
144 case 'c':
145 opt_count = (int)strtol(optarg, NULL, 0);
146 if (opt_count == 0)
147 forever++;
148 break;
149 default:
150 usage();
151 ;
152 }
153 }
154 argc -= optind;
155 argv += optind;
156
157 if (argc != 0)
158 usage();
159
160 st = malloc(opt_nofiles * sizeof(*st));
161 fd = malloc(opt_nofiles * sizeof(*fd));
162 pp = malloc(opt_nofiles * sizeof(*pp));
163
164 while (opt_count-- || forever)
165 testlist[opt_testno].testfn(0);
166
167 return 0;
168 }
169
170 static int
build_files(void)171 build_files(void)
172 {
173 char name[128];
174 int i;
175 int error;
176
177 for (i = 0, error = 0; i < opt_nofiles; i++) {
178 snprintf(name, 128, "tmpfiles/file%d", i);
179 if ((fd[i] = open(name, O_RDWR)) < 1) {
180 if ((fd[i] = open(name, O_RDWR | O_CREAT, 0644)) < 1) {
181 error = errno;
182 break;
183 }
184 randomfill(fd[i]);
185 }
186 if ((fstat(fd[i], &st[i])) == -1) {
187 error = errno;
188 break;
189 }
190 if (opt_verbose) {
191 fprintf(stdout, "\rFile creation, random data filled [%d/%d] ", i+1, opt_nofiles);
192 fflush(stdout);
193 }
194 }
195
196 return error;
197 }
198
199 static void
randomfill(int fd)200 randomfill(int fd)
201 {
202 char buf[32768];
203 long tot;
204 int i;
205
206 srandomdev();
207 tot = opt_mbfile * 1024L;
208 for (i = 0; i < 32768; ++i)
209 buf[i] = random();
210 for (i = 0; i < tot; i += 32) /* 8MB by default */
211 write(fd, buf, 32768);
212 fsync(fd);
213 lseek(fd, 0L, 0);
214 }
215