xref: /openbmc/qemu/tests/migration/stress.c (revision 243af022)
1 /*
2  * Migration stress workload
3  *
4  * Copyright (c) 2016 Red Hat, Inc.
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include <getopt.h>
22 #include <sys/reboot.h>
23 #include <sys/syscall.h>
24 #include <linux/random.h>
25 #include <pthread.h>
26 #include <sys/mount.h>
27 
28 const char *argv0;
29 
30 #define PAGE_SIZE 4096
31 
32 static int gettid(void)
33 {
34     return syscall(SYS_gettid);
35 }
36 
37 static __attribute__((noreturn)) void exit_failure(void)
38 {
39     if (getpid() == 1) {
40         sync();
41         reboot(RB_POWER_OFF);
42         fprintf(stderr, "%s (%05d): ERROR: cannot reboot: %s\n",
43                 argv0, gettid(), strerror(errno));
44         abort();
45     } else {
46         exit(1);
47     }
48 }
49 
50 static __attribute__((noreturn)) void exit_success(void)
51 {
52     if (getpid() == 1) {
53         sync();
54         reboot(RB_POWER_OFF);
55         fprintf(stderr, "%s (%05d): ERROR: cannot reboot: %s\n",
56                 argv0, gettid(), strerror(errno));
57         abort();
58     } else {
59         exit(0);
60     }
61 }
62 
63 static int get_command_arg_str(const char *name,
64                                char **val)
65 {
66     static char line[1024];
67     FILE *fp = fopen("/proc/cmdline", "r");
68     char *start, *end;
69 
70     if (fp == NULL) {
71         fprintf(stderr, "%s (%05d): ERROR: cannot open /proc/cmdline: %s\n",
72                 argv0, gettid(), strerror(errno));
73         return -1;
74     }
75 
76     if (!fgets(line, sizeof line, fp)) {
77         fprintf(stderr, "%s (%05d): ERROR: cannot read /proc/cmdline: %s\n",
78                 argv0, gettid(), strerror(errno));
79         fclose(fp);
80         return -1;
81     }
82     fclose(fp);
83 
84     start = strstr(line, name);
85     if (!start)
86         return 0;
87 
88     start += strlen(name);
89 
90     if (*start != '=') {
91         fprintf(stderr, "%s (%05d): ERROR: no value provided for '%s' in /proc/cmdline\n",
92                 argv0, gettid(), name);
93     }
94     start++;
95 
96     end = strstr(start, " ");
97     if (!end)
98         end = strstr(start, "\n");
99 
100     if (end == start) {
101         fprintf(stderr, "%s (%05d): ERROR: no value provided for '%s' in /proc/cmdline\n",
102                 argv0, gettid(), name);
103         return -1;
104     }
105 
106     if (end)
107         *val = g_strndup(start, end - start);
108     else
109         *val = g_strdup(start);
110     return 1;
111 }
112 
113 
114 static int get_command_arg_ull(const char *name,
115                                unsigned long long *val)
116 {
117     char *valstr;
118     char *end;
119 
120     int ret = get_command_arg_str(name, &valstr);
121     if (ret <= 0)
122         return ret;
123 
124     errno = 0;
125     *val = strtoll(valstr, &end, 10);
126     if (errno || *end) {
127         fprintf(stderr, "%s (%05d): ERROR: cannot parse %s value %s\n",
128                 argv0, gettid(), name, valstr);
129         g_free(valstr);
130         return -1;
131     }
132     g_free(valstr);
133     return 0;
134 }
135 
136 
137 static int random_bytes(char *buf, size_t len)
138 {
139     int fd;
140 
141     fd = open("/dev/urandom", O_RDONLY);
142     if (fd < 0) {
143         fprintf(stderr, "%s (%05d): ERROR: cannot open /dev/urandom: %s\n",
144                 argv0, gettid(), strerror(errno));
145         return -1;
146     }
147 
148     if (read(fd, buf, len) != len) {
149         fprintf(stderr, "%s (%05d): ERROR: cannot read /dev/urandom: %s\n",
150                 argv0, gettid(), strerror(errno));
151         close(fd);
152         return -1;
153     }
154 
155     close(fd);
156 
157     return 0;
158 }
159 
160 
161 static unsigned long long now(void)
162 {
163     struct timeval tv;
164 
165     gettimeofday(&tv, NULL);
166 
167     return (tv.tv_sec * 1000ull) + (tv.tv_usec / 1000ull);
168 }
169 
170 static void stressone(unsigned long long ramsizeMB)
171 {
172     size_t pagesPerMB = 1024 * 1024 / PAGE_SIZE;
173     g_autofree char *ram = g_malloc(ramsizeMB * 1024 * 1024);
174     char *ramptr;
175     size_t i, j, k;
176     g_autofree char *data = g_malloc(PAGE_SIZE);
177     char *dataptr;
178     size_t nMB = 0;
179     unsigned long long before, after;
180 
181     /* We don't care about initial state, but we do want
182      * to fault it all into RAM, otherwise the first iter
183      * of the loop below will be quite slow. We can't use
184      * 0x0 as the byte as gcc optimizes that away into a
185      * calloc instead :-) */
186     memset(ram, 0xfe, ramsizeMB * 1024 * 1024);
187 
188     if (random_bytes(data, PAGE_SIZE) < 0) {
189         return;
190     }
191 
192     before = now();
193 
194     while (1) {
195 
196         ramptr = ram;
197         for (i = 0; i < ramsizeMB; i++, nMB++) {
198             for (j = 0; j < pagesPerMB; j++) {
199                 dataptr = data;
200                 for (k = 0; k < PAGE_SIZE; k += sizeof(long long)) {
201                     ramptr += sizeof(long long);
202                     dataptr += sizeof(long long);
203                     *(unsigned long long *)ramptr ^= *(unsigned long long *)dataptr;
204                 }
205             }
206 
207             if (nMB == 1024) {
208                 after = now();
209                 fprintf(stderr, "%s (%05d): INFO: %06llums copied 1 GB in %05llums\n",
210                         argv0, gettid(), after, after - before);
211                 before = now();
212                 nMB = 0;
213             }
214         }
215     }
216 }
217 
218 
219 static void *stressthread(void *arg)
220 {
221     unsigned long long ramsizeMB = *(unsigned long long *)arg;
222 
223     stressone(ramsizeMB);
224 
225     return NULL;
226 }
227 
228 static void stress(unsigned long long ramsizeGB, int ncpus)
229 {
230     size_t i;
231     unsigned long long ramsizeMB = ramsizeGB * 1024 / ncpus;
232     ncpus--;
233 
234     for (i = 0; i < ncpus; i++) {
235         pthread_t thr;
236         pthread_create(&thr, NULL,
237                        stressthread,   &ramsizeMB);
238     }
239 
240     stressone(ramsizeMB);
241 }
242 
243 
244 static int mount_misc(const char *fstype, const char *dir)
245 {
246     if (mkdir(dir, 0755) < 0 && errno != EEXIST) {
247         fprintf(stderr, "%s (%05d): ERROR: cannot create %s: %s\n",
248                 argv0, gettid(), dir, strerror(errno));
249         return -1;
250     }
251 
252     if (mount("none", dir, fstype, 0, NULL) < 0) {
253         fprintf(stderr, "%s (%05d): ERROR: cannot mount %s: %s\n",
254                 argv0, gettid(), dir, strerror(errno));
255         return -1;
256     }
257 
258     return 0;
259 }
260 
261 static int mount_all(void)
262 {
263     if (mount_misc("proc", "/proc") < 0 ||
264         mount_misc("sysfs", "/sys") < 0 ||
265         mount_misc("tmpfs", "/dev") < 0)
266         return -1;
267 
268     mknod("/dev/urandom", 0777 | S_IFCHR, makedev(1, 9));
269     mknod("/dev/random", 0777 | S_IFCHR, makedev(1, 8));
270 
271     return 0;
272 }
273 
274 int main(int argc, char **argv)
275 {
276     unsigned long long ramsizeGB = 1;
277     char *end;
278     int ch;
279     int opt_ind = 0;
280     const char *sopt = "hr:c:";
281     struct option lopt[] = {
282         { "help", no_argument, NULL, 'h' },
283         { "ramsize", required_argument, NULL, 'r' },
284         { "cpus", required_argument, NULL, 'c' },
285         { NULL, 0, NULL, 0 }
286     };
287     int ret;
288     int ncpus = 0;
289 
290     argv0 = argv[0];
291 
292     while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
293         switch (ch) {
294         case 'r':
295             errno = 0;
296             ramsizeGB = strtoll(optarg, &end, 10);
297             if (errno != 0 || *end) {
298                 fprintf(stderr, "%s (%05d): ERROR: Cannot parse RAM size %s\n",
299                         argv0, gettid(), optarg);
300                 exit_failure();
301             }
302             break;
303 
304         case 'c':
305             errno = 0;
306             ncpus = strtoll(optarg, &end, 10);
307             if (errno != 0 || *end) {
308                 fprintf(stderr, "%s (%05d): ERROR: Cannot parse CPU count %s\n",
309                         argv0, gettid(), optarg);
310                 exit_failure();
311             }
312             break;
313 
314         case '?':
315         case 'h':
316             fprintf(stderr, "%s: [--help][--ramsize GB][--cpus N]\n", argv0);
317             exit_failure();
318         }
319     }
320 
321     if (getpid() == 1) {
322         if (mount_all() < 0)
323             exit_failure();
324 
325         ret = get_command_arg_ull("ramsize", &ramsizeGB);
326         if (ret < 0)
327             exit_failure();
328     }
329 
330     if (ncpus == 0)
331         ncpus = sysconf(_SC_NPROCESSORS_ONLN);
332 
333     fprintf(stdout, "%s (%05d): INFO: RAM %llu GiB across %d CPUs\n",
334             argv0, gettid(), ramsizeGB, ncpus);
335 
336     stress(ramsizeGB, ncpus);
337 
338     exit_failure();
339 }
340