Add test for rcu_assign_pointer()
[urcu.git] / tests / test_urcu_assign.c
1 /*
2 * test_urcu_assign.c
3 *
4 * Userspace RCU library - test program
5 *
6 * Copyright February 2009 - Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21 */
22
23 #define _GNU_SOURCE
24 #include <stdio.h>
25 #include <pthread.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <sys/types.h>
29 #include <sys/wait.h>
30 #include <unistd.h>
31 #include <stdio.h>
32 #include <assert.h>
33 #include <sys/syscall.h>
34 #include <sched.h>
35
36 #include <urcu/arch.h>
37
38 /* hardcoded number of CPUs */
39 #define NR_CPUS 16384
40
41 #if defined(_syscall0)
42 _syscall0(pid_t, gettid)
43 #elif defined(__NR_gettid)
44 static inline pid_t gettid(void)
45 {
46 return syscall(__NR_gettid);
47 }
48 #else
49 #warning "use pid as tid"
50 static inline pid_t gettid(void)
51 {
52 return getpid();
53 }
54 #endif
55
56 #ifndef DYNAMIC_LINK_TEST
57 #define _LGPL_SOURCE
58 #else
59 #define debug_yield_read()
60 #endif
61 #include <urcu.h>
62
63 struct test_array {
64 int a;
65 };
66
67 static volatile int test_go, test_stop;
68
69 static unsigned long wdelay;
70
71 static struct test_array *test_rcu_pointer;
72
73 static unsigned long duration;
74
75 /* read-side C.S. duration, in loops */
76 static unsigned long rduration;
77
78 static inline void loop_sleep(unsigned long l)
79 {
80 while(l-- != 0)
81 cpu_relax();
82 }
83
84 static int verbose_mode;
85
86 #define printf_verbose(fmt, args...) \
87 do { \
88 if (verbose_mode) \
89 printf(fmt, args); \
90 } while (0)
91
92 static unsigned int cpu_affinities[NR_CPUS];
93 static unsigned int next_aff = 0;
94 static int use_affinity = 0;
95
96 pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
97
98 static void set_affinity(void)
99 {
100 cpu_set_t mask;
101 int cpu;
102 int ret;
103
104 if (!use_affinity)
105 return;
106
107 ret = pthread_mutex_lock(&affinity_mutex);
108 if (ret) {
109 perror("Error in pthread mutex lock");
110 exit(-1);
111 }
112 cpu = cpu_affinities[next_aff++];
113 ret = pthread_mutex_unlock(&affinity_mutex);
114 if (ret) {
115 perror("Error in pthread mutex unlock");
116 exit(-1);
117 }
118 CPU_ZERO(&mask);
119 CPU_SET(cpu, &mask);
120 sched_setaffinity(0, sizeof(mask), &mask);
121 }
122
123 /*
124 * returns 0 if test should end.
125 */
126 static int test_duration_write(void)
127 {
128 return !test_stop;
129 }
130
131 static int test_duration_read(void)
132 {
133 return !test_stop;
134 }
135
136 static unsigned long long __thread nr_writes;
137 static unsigned long long __thread nr_reads;
138
139 static unsigned int nr_readers;
140 static unsigned int nr_writers;
141
142 pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
143
144 void rcu_copy_mutex_lock(void)
145 {
146 int ret;
147 ret = pthread_mutex_lock(&rcu_copy_mutex);
148 if (ret) {
149 perror("Error in pthread mutex lock");
150 exit(-1);
151 }
152 }
153
154 void rcu_copy_mutex_unlock(void)
155 {
156 int ret;
157
158 ret = pthread_mutex_unlock(&rcu_copy_mutex);
159 if (ret) {
160 perror("Error in pthread mutex unlock");
161 exit(-1);
162 }
163 }
164
165 /*
166 * malloc/free are reusing memory areas too quickly, which does not let us
167 * test races appropriately. Use a large circular array for allocations.
168 * ARRAY_SIZE is larger than nr_writers, which insures we never run over our tail.
169 */
170 #define ARRAY_SIZE (1048576 * nr_writers)
171 #define ARRAY_POISON 0xDEADBEEF
172 static int array_index;
173 static struct test_array *test_array;
174
175 static struct test_array *test_array_alloc(void)
176 {
177 struct test_array *ret;
178 int index;
179
180 rcu_copy_mutex_lock();
181 index = array_index % ARRAY_SIZE;
182 assert(test_array[index].a == ARRAY_POISON ||
183 test_array[index].a == 0);
184 ret = &test_array[index];
185 array_index++;
186 if (array_index == ARRAY_SIZE)
187 array_index = 0;
188 rcu_copy_mutex_unlock();
189 return ret;
190 }
191
192 static void test_array_free(struct test_array *ptr)
193 {
194 if (!ptr)
195 return;
196 rcu_copy_mutex_lock();
197 ptr->a = ARRAY_POISON;
198 rcu_copy_mutex_unlock();
199 }
200
201 void *thr_reader(void *_count)
202 {
203 unsigned long long *count = _count;
204 struct test_array *local_ptr;
205
206 printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
207 "reader", pthread_self(), (unsigned long)gettid());
208
209 set_affinity();
210
211 rcu_register_thread();
212
213 while (!test_go)
214 {
215 }
216 smp_mb();
217
218 for (;;) {
219 rcu_read_lock();
220 local_ptr = rcu_dereference(test_rcu_pointer);
221 debug_yield_read();
222 if (local_ptr)
223 assert(local_ptr->a == 8);
224 if (unlikely(rduration))
225 loop_sleep(rduration);
226 rcu_read_unlock();
227 nr_reads++;
228 if (unlikely(!test_duration_read()))
229 break;
230 }
231
232 rcu_unregister_thread();
233
234 *count = nr_reads;
235 printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
236 "reader", pthread_self(), (unsigned long)gettid());
237 return ((void*)1);
238
239 }
240
241 void *thr_writer(void *_count)
242 {
243 unsigned long long *count = _count;
244 struct test_array *new, *old;
245
246 printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
247 "writer", pthread_self(), (unsigned long)gettid());
248
249 set_affinity();
250
251 while (!test_go)
252 {
253 }
254 smp_mb();
255
256 for (;;) {
257 new = test_array_alloc();
258 new->a = 8;
259 rcu_copy_mutex_lock();
260 old = test_rcu_pointer;
261 rcu_assign_pointer(test_rcu_pointer, new);
262 rcu_copy_mutex_unlock();
263 synchronize_rcu();
264 if (old)
265 old->a = 0;
266 test_array_free(old);
267 nr_writes++;
268 if (unlikely(!test_duration_write()))
269 break;
270 if (unlikely(wdelay))
271 loop_sleep(wdelay);
272 }
273
274 printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
275 "writer", pthread_self(), (unsigned long)gettid());
276 *count = nr_writes;
277 return ((void*)2);
278 }
279
280 void show_usage(int argc, char **argv)
281 {
282 printf("Usage : %s nr_readers nr_writers duration (s)", argv[0]);
283 #ifdef DEBUG_YIELD
284 printf(" [-r] [-w] (yield reader and/or writer)");
285 #endif
286 printf(" [-d delay] (writer period (us))");
287 printf(" [-c duration] (reader C.S. duration (in loops))");
288 printf(" [-v] (verbose output)");
289 printf(" [-a cpu#] [-a cpu#]... (affinity)");
290 printf("\n");
291 }
292
293 int main(int argc, char **argv)
294 {
295 int err;
296 pthread_t *tid_reader, *tid_writer;
297 void *tret;
298 unsigned long long *count_reader, *count_writer;
299 unsigned long long tot_reads = 0, tot_writes = 0;
300 int i, a;
301
302 if (argc < 4) {
303 show_usage(argc, argv);
304 return -1;
305 }
306
307 err = sscanf(argv[1], "%u", &nr_readers);
308 if (err != 1) {
309 show_usage(argc, argv);
310 return -1;
311 }
312
313 err = sscanf(argv[2], "%u", &nr_writers);
314 if (err != 1) {
315 show_usage(argc, argv);
316 return -1;
317 }
318
319 err = sscanf(argv[3], "%lu", &duration);
320 if (err != 1) {
321 show_usage(argc, argv);
322 return -1;
323 }
324
325 for (i = 4; i < argc; i++) {
326 if (argv[i][0] != '-')
327 continue;
328 switch (argv[i][1]) {
329 #ifdef DEBUG_YIELD
330 case 'r':
331 yield_active |= YIELD_READ;
332 break;
333 case 'w':
334 yield_active |= YIELD_WRITE;
335 break;
336 #endif
337 case 'a':
338 if (argc < i + 2) {
339 show_usage(argc, argv);
340 return -1;
341 }
342 a = atoi(argv[++i]);
343 cpu_affinities[next_aff++] = a;
344 use_affinity = 1;
345 printf_verbose("Adding CPU %d affinity\n", a);
346 break;
347 case 'c':
348 if (argc < i + 2) {
349 show_usage(argc, argv);
350 return -1;
351 }
352 rduration = atol(argv[++i]);
353 break;
354 case 'd':
355 if (argc < i + 2) {
356 show_usage(argc, argv);
357 return -1;
358 }
359 wdelay = atol(argv[++i]);
360 break;
361 case 'v':
362 verbose_mode = 1;
363 break;
364 }
365 }
366
367 printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
368 duration, nr_readers, nr_writers);
369 printf_verbose("Writer delay : %lu loops.\n", wdelay);
370 printf_verbose("Reader duration : %lu loops.\n", rduration);
371 printf_verbose("thread %-6s, thread id : %lx, tid %lu\n",
372 "main", pthread_self(), (unsigned long)gettid());
373
374 test_array = malloc(sizeof(*test_array) * ARRAY_SIZE);
375 tid_reader = malloc(sizeof(*tid_reader) * nr_readers);
376 tid_writer = malloc(sizeof(*tid_writer) * nr_writers);
377 count_reader = malloc(sizeof(*count_reader) * nr_readers);
378 count_writer = malloc(sizeof(*count_writer) * nr_writers);
379
380 next_aff = 0;
381
382 for (i = 0; i < nr_readers; i++) {
383 err = pthread_create(&tid_reader[i], NULL, thr_reader,
384 &count_reader[i]);
385 if (err != 0)
386 exit(1);
387 }
388 for (i = 0; i < nr_writers; i++) {
389 err = pthread_create(&tid_writer[i], NULL, thr_writer,
390 &count_writer[i]);
391 if (err != 0)
392 exit(1);
393 }
394
395 smp_mb();
396
397 test_go = 1;
398
399 sleep(duration);
400
401 test_stop = 1;
402
403 for (i = 0; i < nr_readers; i++) {
404 err = pthread_join(tid_reader[i], &tret);
405 if (err != 0)
406 exit(1);
407 tot_reads += count_reader[i];
408 }
409 for (i = 0; i < nr_writers; i++) {
410 err = pthread_join(tid_writer[i], &tret);
411 if (err != 0)
412 exit(1);
413 tot_writes += count_writer[i];
414 }
415
416 printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
417 tot_writes);
418 printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu "
419 "nr_writers %3u "
420 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
421 argv[0], duration, nr_readers, rduration,
422 nr_writers, wdelay, tot_reads, tot_writes,
423 tot_reads + tot_writes);
424 test_array_free(test_rcu_pointer);
425 free(test_array);
426 free(tid_reader);
427 free(tid_writer);
428 free(count_reader);
429 free(count_writer);
430 return 0;
431 }
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