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@efficios.com>
   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 "../config.h"
  25 #include <stdio.h>
  26 #include <pthread.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <sys/types.h>
  30 #include <sys/wait.h>
  31 #include <unistd.h>
  32 #include <stdio.h>
  33 #include <assert.h>
  34 #include <errno.h>
  35
  36 #include <urcu/arch.h>
  37 #include <urcu/tls-compat.h>
  38 #include "cpuset.h"
  39 #include "thread-id.h"
  40
  41 /* hardcoded number of CPUs */
  42 #define NR_CPUS 16384
  43
  44 #ifndef DYNAMIC_LINK_TEST
  45 #define _LGPL_SOURCE
  46 #else
  47 #define rcu_debug_yield_read()
  48 #endif
  49 #include <urcu.h>
  50
  51 struct test_array {
  52         int a;
  53 };
  54
  55 static volatile int test_go, test_stop;
  56
  57 static unsigned long wdelay;
  58
  59 static struct test_array *test_rcu_pointer;
  60
  61 static unsigned long duration;
  62
  63 /* read-side C.S. duration, in loops */
  64 static unsigned long rduration;
  65
  66 /* write-side C.S. duration, in loops */
  67 static unsigned long wduration;
  68
  69 static inline void loop_sleep(unsigned long loops)
  70 {
  71         while (loops-- != 0)
  72                 caa_cpu_relax();
  73 }
  74
  75 static int verbose_mode;
  76
  77 #define printf_verbose(fmt, args...)            \
  78         do {                                    \
  79                 if (verbose_mode)               \
  80                         printf(fmt, args);      \
  81         } while (0)
  82
  83 static unsigned int cpu_affinities[NR_CPUS];
  84 static unsigned int next_aff = 0;
  85 static int use_affinity = 0;
  86
  87 pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
  88
  89 static void set_affinity(void)
  90 {
  91 #if HAVE_SCHED_SETAFFINITY
  92         cpu_set_t mask;
  93         int cpu, ret;
  94 #endif /* HAVE_SCHED_SETAFFINITY */
  95
  96         if (!use_affinity)
  97                 return;
  98
  99 #if HAVE_SCHED_SETAFFINITY
 100         ret = pthread_mutex_lock(&affinity_mutex);
 101         if (ret) {
 102                 perror("Error in pthread mutex lock");
 103                 exit(-1);
 104         }
 105         cpu = cpu_affinities[next_aff++];
 106         ret = pthread_mutex_unlock(&affinity_mutex);
 107         if (ret) {
 108                 perror("Error in pthread mutex unlock");
 109                 exit(-1);
 110         }
 111
 112         CPU_ZERO(&mask);
 113         CPU_SET(cpu, &mask);
 114 #if SCHED_SETAFFINITY_ARGS == 2
 115         sched_setaffinity(0, &mask);
 116 #else
 117         sched_setaffinity(0, sizeof(mask), &mask);
 118 #endif
 119 #endif /* HAVE_SCHED_SETAFFINITY */
 120 }
 121
 122 /*
 123  * returns 0 if test should end.
 124  */
 125 static int test_duration_write(void)
 126 {
 127         return !test_stop;
 128 }
 129
 130 static int test_duration_read(void)
 131 {
 132         return !test_stop;
 133 }
 134
 135 static DEFINE_URCU_TLS(unsigned long long, nr_writes);
 136 static DEFINE_URCU_TLS(unsigned long long, nr_reads);
 137
 138 static unsigned int nr_readers;
 139 static unsigned int nr_writers;
 140
 141 pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
 142
 143 void rcu_copy_mutex_lock(void)
 144 {
 145         int ret;
 146         ret = pthread_mutex_lock(&rcu_copy_mutex);
 147         if (ret) {
 148                 perror("Error in pthread mutex lock");
 149                 exit(-1);
 150         }
 151 }
 152
 153 void rcu_copy_mutex_unlock(void)
 154 {
 155         int ret;
 156
 157         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 158         if (ret) {
 159                 perror("Error in pthread mutex unlock");
 160                 exit(-1);
 161         }
 162 }
 163
 164 /*
 165  * malloc/free are reusing memory areas too quickly, which does not let us
 166  * test races appropriately. Use a large circular array for allocations.
 167  * ARRAY_SIZE is larger than nr_writers, and we keep the mutex across
 168  * both alloc and free, 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         index = array_index % ARRAY_SIZE;
 181         assert(test_array[index].a == ARRAY_POISON ||
 182                 test_array[index].a == 0);
 183         ret = &test_array[index];
 184         array_index++;
 185         if (array_index == ARRAY_SIZE)
 186                 array_index = 0;
 187         return ret;
 188 }
 189
 190 static void test_array_free(struct test_array *ptr)
 191 {
 192         if (!ptr)
 193                 return;
 194         ptr->a = ARRAY_POISON;
 195 }
 196
 197 void *thr_reader(void *_count)
 198 {
 199         unsigned long long *count = _count;
 200         struct test_array *local_ptr;
 201
 202         printf_verbose("thread_begin %s, tid %lu\n",
 203                         "reader", urcu_get_thread_id());
 204
 205         set_affinity();
 206
 207         rcu_register_thread();
 208
 209         while (!test_go)
 210         {
 211         }
 212         cmm_smp_mb();
 213
 214         for (;;) {
 215                 rcu_read_lock();
 216                 local_ptr = rcu_dereference(test_rcu_pointer);
 217                 rcu_debug_yield_read();
 218                 if (local_ptr)
 219                         assert(local_ptr->a == 8);
 220                 if (caa_unlikely(rduration))
 221                         loop_sleep(rduration);
 222                 rcu_read_unlock();
 223                 URCU_TLS(nr_reads)++;
 224                 if (caa_unlikely(!test_duration_read()))
 225                         break;
 226         }
 227
 228         rcu_unregister_thread();
 229
 230         *count = URCU_TLS(nr_reads);
 231         printf_verbose("thread_end %s, tid %lu\n",
 232                         "reader", urcu_get_thread_id());
 233         return ((void*)1);
 234
 235 }
 236
 237 void *thr_writer(void *_count)
 238 {
 239         unsigned long long *count = _count;
 240         struct test_array *new, *old;
 241
 242         printf_verbose("thread_begin %s, tid %lu\n",
 243                         "writer", urcu_get_thread_id());
 244
 245         set_affinity();
 246
 247         while (!test_go)
 248         {
 249         }
 250         cmm_smp_mb();
 251
 252         for (;;) {
 253                 rcu_copy_mutex_lock();
 254                 new = test_array_alloc();
 255                 new->a = 8;
 256                 old = test_rcu_pointer;
 257                 rcu_assign_pointer(test_rcu_pointer, new);
 258                 if (caa_unlikely(wduration))
 259                         loop_sleep(wduration);
 260                 synchronize_rcu();
 261                 if (old)
 262                         old->a = 0;
 263                 test_array_free(old);
 264                 rcu_copy_mutex_unlock();
 265                 URCU_TLS(nr_writes)++;
 266                 if (caa_unlikely(!test_duration_write()))
 267                         break;
 268                 if (caa_unlikely(wdelay))
 269                         loop_sleep(wdelay);
 270         }
 271
 272         printf_verbose("thread_end %s, tid %lu\n",
 273                         "writer", urcu_get_thread_id());
 274         *count = URCU_TLS(nr_writes);
 275         return ((void*)2);
 276 }
 277
 278 void show_usage(int argc, char **argv)
 279 {
 280         printf("Usage : %s nr_readers nr_writers duration (s) <OPTIONS>\n",
 281                 argv[0]);
 282         printf("OPTIONS:\n");
 283 #ifdef DEBUG_YIELD
 284         printf("        [-r] [-w] (yield reader and/or writer)\n");
 285 #endif
 286         printf("        [-d delay] (writer period (us))\n");
 287         printf("        [-c duration] (reader C.S. duration (in loops))\n");
 288         printf("        [-e duration] (writer C.S. duration (in loops))\n");
 289         printf("        [-v] (verbose output)\n");
 290         printf("        [-a cpu#] [-a cpu#]... (affinity)\n");
 291         printf("\n");
 292 }
 293
 294 int main(int argc, char **argv)
 295 {
 296         int err;
 297         pthread_t *tid_reader, *tid_writer;
 298         void *tret;
 299         unsigned long long *count_reader, *count_writer;
 300         unsigned long long tot_reads = 0, tot_writes = 0;
 301         int i, a;
 302
 303         if (argc < 4) {
 304                 show_usage(argc, argv);
 305                 return -1;
 306         }
 307
 308         err = sscanf(argv[1], "%u", &nr_readers);
 309         if (err != 1) {
 310                 show_usage(argc, argv);
 311                 return -1;
 312         }
 313
 314         err = sscanf(argv[2], "%u", &nr_writers);
 315         if (err != 1) {
 316                 show_usage(argc, argv);
 317                 return -1;
 318         }
 319
 320         err = sscanf(argv[3], "%lu", &duration);
 321         if (err != 1) {
 322                 show_usage(argc, argv);
 323                 return -1;
 324         }
 325
 326         for (i = 4; i < argc; i++) {
 327                 if (argv[i][0] != '-')
 328                         continue;
 329                 switch (argv[i][1]) {
 330 #ifdef DEBUG_YIELD
 331                 case 'r':
 332                         rcu_yield_active |= RCU_YIELD_READ;
 333                         break;
 334                 case 'w':
 335                         rcu_yield_active |= RCU_YIELD_WRITE;
 336                         break;
 337 #endif
 338                 case 'a':
 339                         if (argc < i + 2) {
 340                                 show_usage(argc, argv);
 341                                 return -1;
 342                         }
 343                         a = atoi(argv[++i]);
 344                         cpu_affinities[next_aff++] = a;
 345                         use_affinity = 1;
 346                         printf_verbose("Adding CPU %d affinity\n", a);
 347                         break;
 348                 case 'c':
 349                         if (argc < i + 2) {
 350                                 show_usage(argc, argv);
 351                                 return -1;
 352                         }
 353                         rduration = atol(argv[++i]);
 354                         break;
 355                 case 'd':
 356                         if (argc < i + 2) {
 357                                 show_usage(argc, argv);
 358                                 return -1;
 359                         }
 360                         wdelay = atol(argv[++i]);
 361                         break;
 362                 case 'e':
 363                         if (argc < i + 2) {
 364                                 show_usage(argc, argv);
 365                                 return -1;
 366                         }
 367                         wduration = atol(argv[++i]);
 368                         break;
 369                 case 'v':
 370                         verbose_mode = 1;
 371                         break;
 372                 }
 373         }
 374
 375         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 376                 duration, nr_readers, nr_writers);
 377         printf_verbose("Writer delay : %lu loops.\n", wdelay);
 378         printf_verbose("Reader duration : %lu loops.\n", rduration);
 379         printf_verbose("thread %-6s, tid %lu\n",
 380                         "main", urcu_get_thread_id());
 381
 382         test_array = calloc(1, sizeof(*test_array) * ARRAY_SIZE);
 383         tid_reader = malloc(sizeof(*tid_reader) * nr_readers);
 384         tid_writer = malloc(sizeof(*tid_writer) * nr_writers);
 385         count_reader = malloc(sizeof(*count_reader) * nr_readers);
 386         count_writer = malloc(sizeof(*count_writer) * nr_writers);
 387
 388         next_aff = 0;
 389
 390         for (i = 0; i < nr_readers; i++) {
 391                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 392                                      &count_reader[i]);
 393                 if (err != 0)
 394                         exit(1);
 395         }
 396         for (i = 0; i < nr_writers; i++) {
 397                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 398                                      &count_writer[i]);
 399                 if (err != 0)
 400                         exit(1);
 401         }
 402
 403         cmm_smp_mb();
 404
 405         test_go = 1;
 406
 407         sleep(duration);
 408
 409         test_stop = 1;
 410
 411         for (i = 0; i < nr_readers; i++) {
 412                 err = pthread_join(tid_reader[i], &tret);
 413                 if (err != 0)
 414                         exit(1);
 415                 tot_reads += count_reader[i];
 416         }
 417         for (i = 0; i < nr_writers; i++) {
 418                 err = pthread_join(tid_writer[i], &tret);
 419                 if (err != 0)
 420                         exit(1);
 421                 tot_writes += count_writer[i];
 422         }
 423
 424         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 425                tot_writes);
 426         printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu wdur %6lu "
 427                 "nr_writers %3u "
 428                 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
 429                 argv[0], duration, nr_readers, rduration, wduration,
 430                 nr_writers, wdelay, tot_reads, tot_writes,
 431                 tot_reads + tot_writes);
 432         test_array_free(test_rcu_pointer);
 433         free(test_array);
 434         free(tid_reader);
 435         free(tid_writer);
 436         free(count_reader);
 437         free(count_writer);
 438         return 0;
 439 }