test-rcu-list.c (10654B)
1 /* 2 * rcuq_test.c 3 * 4 * usage: rcuq_test <readers> <duration> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program 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 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 19 * 20 * Copyright (c) 2013 Mike D. Day, IBM Corporation. 21 */ 22 23 #include "qemu/osdep.h" 24 #include "qemu/atomic.h" 25 #include "qemu/rcu.h" 26 #include "qemu/thread.h" 27 #include "qemu/rcu_queue.h" 28 29 /* 30 * Test variables. 31 */ 32 33 static QemuMutex counts_mutex; 34 static long long n_reads = 0LL; 35 static long long n_updates = 0LL; 36 static int64_t n_reclaims; 37 static int64_t n_nodes_removed; 38 static long long n_nodes = 0LL; 39 static int g_test_in_charge = 0; 40 41 static int nthreadsrunning; 42 43 #define GOFLAG_INIT 0 44 #define GOFLAG_RUN 1 45 #define GOFLAG_STOP 2 46 47 static int goflag = GOFLAG_INIT; 48 49 #define RCU_READ_RUN 1000 50 #define RCU_UPDATE_RUN 10 51 #define NR_THREADS 100 52 #define RCU_Q_LEN 100 53 54 static QemuThread threads[NR_THREADS]; 55 static struct rcu_reader_data *data[NR_THREADS]; 56 static int n_threads; 57 58 static int select_random_el(int max) 59 { 60 return (rand() % max); 61 } 62 63 64 static void create_thread(void *(*func)(void *)) 65 { 66 if (n_threads >= NR_THREADS) { 67 fprintf(stderr, "Thread limit of %d exceeded!\n", NR_THREADS); 68 exit(-1); 69 } 70 qemu_thread_create(&threads[n_threads], "test", func, &data[n_threads], 71 QEMU_THREAD_JOINABLE); 72 n_threads++; 73 } 74 75 static void wait_all_threads(void) 76 { 77 int i; 78 79 for (i = 0; i < n_threads; i++) { 80 qemu_thread_join(&threads[i]); 81 } 82 n_threads = 0; 83 } 84 85 #ifndef TEST_LIST_TYPE 86 #define TEST_LIST_TYPE 1 87 #endif 88 89 struct list_element { 90 #if TEST_LIST_TYPE == 1 91 QLIST_ENTRY(list_element) entry; 92 #elif TEST_LIST_TYPE == 2 93 QSIMPLEQ_ENTRY(list_element) entry; 94 #elif TEST_LIST_TYPE == 3 95 QTAILQ_ENTRY(list_element) entry; 96 #elif TEST_LIST_TYPE == 4 97 QSLIST_ENTRY(list_element) entry; 98 #else 99 #error Invalid TEST_LIST_TYPE 100 #endif 101 struct rcu_head rcu; 102 }; 103 104 static void reclaim_list_el(struct rcu_head *prcu) 105 { 106 struct list_element *el = container_of(prcu, struct list_element, rcu); 107 g_free(el); 108 /* Accessed only from call_rcu thread. */ 109 qatomic_set_i64(&n_reclaims, n_reclaims + 1); 110 } 111 112 #if TEST_LIST_TYPE == 1 113 static QLIST_HEAD(, list_element) Q_list_head; 114 115 #define TEST_NAME "qlist" 116 #define TEST_LIST_REMOVE_RCU QLIST_REMOVE_RCU 117 #define TEST_LIST_INSERT_AFTER_RCU QLIST_INSERT_AFTER_RCU 118 #define TEST_LIST_INSERT_HEAD_RCU QLIST_INSERT_HEAD_RCU 119 #define TEST_LIST_FOREACH_RCU QLIST_FOREACH_RCU 120 #define TEST_LIST_FOREACH_SAFE_RCU QLIST_FOREACH_SAFE_RCU 121 122 #elif TEST_LIST_TYPE == 2 123 static QSIMPLEQ_HEAD(, list_element) Q_list_head = 124 QSIMPLEQ_HEAD_INITIALIZER(Q_list_head); 125 126 #define TEST_NAME "qsimpleq" 127 #define TEST_LIST_REMOVE_RCU(el, f) \ 128 QSIMPLEQ_REMOVE_RCU(&Q_list_head, el, list_element, f) 129 130 #define TEST_LIST_INSERT_AFTER_RCU(list_el, el, f) \ 131 QSIMPLEQ_INSERT_AFTER_RCU(&Q_list_head, list_el, el, f) 132 133 #define TEST_LIST_INSERT_HEAD_RCU QSIMPLEQ_INSERT_HEAD_RCU 134 #define TEST_LIST_FOREACH_RCU QSIMPLEQ_FOREACH_RCU 135 #define TEST_LIST_FOREACH_SAFE_RCU QSIMPLEQ_FOREACH_SAFE_RCU 136 137 #elif TEST_LIST_TYPE == 3 138 static QTAILQ_HEAD(, list_element) Q_list_head; 139 140 #define TEST_NAME "qtailq" 141 #define TEST_LIST_REMOVE_RCU(el, f) QTAILQ_REMOVE_RCU(&Q_list_head, el, f) 142 143 #define TEST_LIST_INSERT_AFTER_RCU(list_el, el, f) \ 144 QTAILQ_INSERT_AFTER_RCU(&Q_list_head, list_el, el, f) 145 146 #define TEST_LIST_INSERT_HEAD_RCU QTAILQ_INSERT_HEAD_RCU 147 #define TEST_LIST_FOREACH_RCU QTAILQ_FOREACH_RCU 148 #define TEST_LIST_FOREACH_SAFE_RCU QTAILQ_FOREACH_SAFE_RCU 149 150 #elif TEST_LIST_TYPE == 4 151 static QSLIST_HEAD(, list_element) Q_list_head; 152 153 #define TEST_NAME "qslist" 154 #define TEST_LIST_REMOVE_RCU(el, f) \ 155 QSLIST_REMOVE_RCU(&Q_list_head, el, list_element, f) 156 157 #define TEST_LIST_INSERT_AFTER_RCU(list_el, el, f) \ 158 QSLIST_INSERT_AFTER_RCU(&Q_list_head, list_el, el, f) 159 160 #define TEST_LIST_INSERT_HEAD_RCU QSLIST_INSERT_HEAD_RCU 161 #define TEST_LIST_FOREACH_RCU QSLIST_FOREACH_RCU 162 #define TEST_LIST_FOREACH_SAFE_RCU QSLIST_FOREACH_SAFE_RCU 163 #else 164 #error Invalid TEST_LIST_TYPE 165 #endif 166 167 static void *rcu_q_reader(void *arg) 168 { 169 long long n_reads_local = 0; 170 struct list_element *el; 171 172 rcu_register_thread(); 173 174 *(struct rcu_reader_data **)arg = get_ptr_rcu_reader(); 175 qatomic_inc(&nthreadsrunning); 176 while (qatomic_read(&goflag) == GOFLAG_INIT) { 177 g_usleep(1000); 178 } 179 180 while (qatomic_read(&goflag) == GOFLAG_RUN) { 181 rcu_read_lock(); 182 TEST_LIST_FOREACH_RCU(el, &Q_list_head, entry) { 183 n_reads_local++; 184 if (qatomic_read(&goflag) == GOFLAG_STOP) { 185 break; 186 } 187 } 188 rcu_read_unlock(); 189 190 g_usleep(100); 191 } 192 qemu_mutex_lock(&counts_mutex); 193 n_reads += n_reads_local; 194 qemu_mutex_unlock(&counts_mutex); 195 196 rcu_unregister_thread(); 197 return NULL; 198 } 199 200 201 static void *rcu_q_updater(void *arg) 202 { 203 int j, target_el; 204 long long n_nodes_local = 0; 205 long long n_updates_local = 0; 206 long long n_removed_local = 0; 207 struct list_element *el, *prev_el; 208 209 *(struct rcu_reader_data **)arg = get_ptr_rcu_reader(); 210 qatomic_inc(&nthreadsrunning); 211 while (qatomic_read(&goflag) == GOFLAG_INIT) { 212 g_usleep(1000); 213 } 214 215 while (qatomic_read(&goflag) == GOFLAG_RUN) { 216 target_el = select_random_el(RCU_Q_LEN); 217 j = 0; 218 /* FOREACH_RCU could work here but let's use both macros */ 219 TEST_LIST_FOREACH_SAFE_RCU(prev_el, &Q_list_head, entry, el) { 220 j++; 221 if (target_el == j) { 222 TEST_LIST_REMOVE_RCU(prev_el, entry); 223 /* may be more than one updater in the future */ 224 call_rcu1(&prev_el->rcu, reclaim_list_el); 225 n_removed_local++; 226 break; 227 } 228 } 229 if (qatomic_read(&goflag) == GOFLAG_STOP) { 230 break; 231 } 232 target_el = select_random_el(RCU_Q_LEN); 233 j = 0; 234 TEST_LIST_FOREACH_RCU(el, &Q_list_head, entry) { 235 j++; 236 if (target_el == j) { 237 struct list_element *new_el = g_new(struct list_element, 1); 238 n_nodes_local++; 239 TEST_LIST_INSERT_AFTER_RCU(el, new_el, entry); 240 break; 241 } 242 } 243 244 n_updates_local += 2; 245 synchronize_rcu(); 246 } 247 synchronize_rcu(); 248 qemu_mutex_lock(&counts_mutex); 249 n_nodes += n_nodes_local; 250 n_updates += n_updates_local; 251 qatomic_set_i64(&n_nodes_removed, n_nodes_removed + n_removed_local); 252 qemu_mutex_unlock(&counts_mutex); 253 return NULL; 254 } 255 256 static void rcu_qtest_init(void) 257 { 258 struct list_element *new_el; 259 int i; 260 nthreadsrunning = 0; 261 srand(time(0)); 262 for (i = 0; i < RCU_Q_LEN; i++) { 263 new_el = g_new(struct list_element, 1); 264 TEST_LIST_INSERT_HEAD_RCU(&Q_list_head, new_el, entry); 265 } 266 qemu_mutex_lock(&counts_mutex); 267 n_nodes += RCU_Q_LEN; 268 qemu_mutex_unlock(&counts_mutex); 269 } 270 271 static void rcu_qtest_run(int duration, int nreaders) 272 { 273 int nthreads = nreaders + 1; 274 while (qatomic_read(&nthreadsrunning) < nthreads) { 275 g_usleep(1000); 276 } 277 278 qatomic_set(&goflag, GOFLAG_RUN); 279 sleep(duration); 280 qatomic_set(&goflag, GOFLAG_STOP); 281 wait_all_threads(); 282 } 283 284 285 static void rcu_qtest(const char *test, int duration, int nreaders) 286 { 287 int i; 288 long long n_removed_local = 0; 289 290 struct list_element *el, *prev_el; 291 292 rcu_qtest_init(); 293 for (i = 0; i < nreaders; i++) { 294 create_thread(rcu_q_reader); 295 } 296 create_thread(rcu_q_updater); 297 rcu_qtest_run(duration, nreaders); 298 299 TEST_LIST_FOREACH_SAFE_RCU(prev_el, &Q_list_head, entry, el) { 300 TEST_LIST_REMOVE_RCU(prev_el, entry); 301 call_rcu1(&prev_el->rcu, reclaim_list_el); 302 n_removed_local++; 303 } 304 qemu_mutex_lock(&counts_mutex); 305 qatomic_set_i64(&n_nodes_removed, n_nodes_removed + n_removed_local); 306 qemu_mutex_unlock(&counts_mutex); 307 synchronize_rcu(); 308 while (qatomic_read_i64(&n_nodes_removed) > 309 qatomic_read_i64(&n_reclaims)) { 310 g_usleep(100); 311 synchronize_rcu(); 312 } 313 if (g_test_in_charge) { 314 g_assert_cmpint(qatomic_read_i64(&n_nodes_removed), ==, 315 qatomic_read_i64(&n_reclaims)); 316 } else { 317 printf("%s: %d readers; 1 updater; nodes read: " \ 318 "%lld, nodes removed: %"PRIi64"; nodes reclaimed: %"PRIi64"\n", 319 test, nthreadsrunning - 1, n_reads, 320 qatomic_read_i64(&n_nodes_removed), 321 qatomic_read_i64(&n_reclaims)); 322 exit(0); 323 } 324 } 325 326 static void usage(int argc, char *argv[]) 327 { 328 fprintf(stderr, "Usage: %s duration nreaders\n", argv[0]); 329 exit(-1); 330 } 331 332 static int gtest_seconds; 333 334 static void gtest_rcuq_one(void) 335 { 336 rcu_qtest("rcuqtest", gtest_seconds / 4, 1); 337 } 338 339 static void gtest_rcuq_few(void) 340 { 341 rcu_qtest("rcuqtest", gtest_seconds / 4, 5); 342 } 343 344 static void gtest_rcuq_many(void) 345 { 346 rcu_qtest("rcuqtest", gtest_seconds / 2, 20); 347 } 348 349 350 int main(int argc, char *argv[]) 351 { 352 int duration = 0, readers = 0; 353 354 qemu_mutex_init(&counts_mutex); 355 if (argc >= 2) { 356 if (argv[1][0] == '-') { 357 g_test_init(&argc, &argv, NULL); 358 if (g_test_quick()) { 359 gtest_seconds = 4; 360 } else { 361 gtest_seconds = 20; 362 } 363 g_test_add_func("/rcu/"TEST_NAME"/single-threaded", gtest_rcuq_one); 364 g_test_add_func("/rcu/"TEST_NAME"/short-few", gtest_rcuq_few); 365 g_test_add_func("/rcu/"TEST_NAME"/long-many", gtest_rcuq_many); 366 g_test_in_charge = 1; 367 return g_test_run(); 368 } 369 duration = strtoul(argv[1], NULL, 0); 370 } 371 if (argc >= 3) { 372 readers = strtoul(argv[2], NULL, 0); 373 } 374 if (duration && readers) { 375 rcu_qtest(argv[0], duration, readers); 376 return 0; 377 } 378 379 usage(argc, argv); 380 return -1; 381 }