tests/benchmark/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 #include <stdio.h>
  24 #include <pthread.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <sys/types.h>
  28 #include <sys/wait.h>
  29 #include <unistd.h>
  30 #include <stdio.h>
  31 #include <assert.h>
  32 #include <errno.h>
  33
  34 #include <urcu/arch.h>
  35 #include <urcu/tls-compat.h>
  36 #include "cpuset.h"
  37 #include "thread-id.h"
  38 #include "../common/debug-yield.h"
  39
  40 /* hardcoded number of CPUs */
  41 #define NR_CPUS 16384
  42
  43 #ifndef DYNAMIC_LINK_TEST
  44 #define _LGPL_SOURCE
  45 #endif
  46 #include <urcu.h>
  47
  48 struct test_array {
  49         int a;
  50 };
  51
  52 static volatile int test_go, test_stop;
  53
  54 static unsigned long wdelay;
  55
  56 static struct test_array *test_rcu_pointer;
  57
  58 static unsigned long duration;
  59
  60 /* read-side C.S. duration, in loops */
  61 static unsigned long rduration;
  62
  63 /* write-side C.S. duration, in loops */
  64 static unsigned long wduration;
  65
  66 static inline void loop_sleep(unsigned long loops)
  67 {
  68         while (loops-- != 0)
  69                 caa_cpu_relax();
  70 }
  71
  72 static int verbose_mode;
  73
  74 #define printf_verbose(fmt, args...)            \
  75         do {                                    \
  76                 if (verbose_mode)               \
  77                         printf(fmt, args);      \
  78         } while (0)
  79
  80 static unsigned int cpu_affinities[NR_CPUS];
  81 static unsigned int next_aff = 0;
  82 static int use_affinity = 0;
  83
  84 pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
  85
  86 static void set_affinity(void)
  87 {
  88 #if HAVE_SCHED_SETAFFINITY
  89         cpu_set_t mask;
  90         int cpu, ret;
  91 #endif /* HAVE_SCHED_SETAFFINITY */
  92
  93         if (!use_affinity)
  94                 return;
  95
  96 #if HAVE_SCHED_SETAFFINITY
  97         ret = pthread_mutex_lock(&affinity_mutex);
  98         if (ret) {
  99                 perror("Error in pthread mutex lock");
 100                 exit(-1);
 101         }
 102         cpu = cpu_affinities[next_aff++];
 103         ret = pthread_mutex_unlock(&affinity_mutex);
 104         if (ret) {
 105                 perror("Error in pthread mutex unlock");
 106                 exit(-1);
 107         }
 108
 109         CPU_ZERO(&mask);
 110         CPU_SET(cpu, &mask);
 111 #if SCHED_SETAFFINITY_ARGS == 2
 112         sched_setaffinity(0, &mask);
 113 #else
 114         sched_setaffinity(0, sizeof(mask), &mask);
 115 #endif
 116 #endif /* HAVE_SCHED_SETAFFINITY */
 117 }
 118
 119 /*
 120  * returns 0 if test should end.
 121  */
 122 static int test_duration_write(void)
 123 {
 124         return !test_stop;
 125 }
 126
 127 static int test_duration_read(void)
 128 {
 129         return !test_stop;
 130 }
 131
 132 static DEFINE_URCU_TLS(unsigned long long, nr_writes);
 133 static DEFINE_URCU_TLS(unsigned long long, nr_reads);
 134
 135 static unsigned int nr_readers;
 136 static unsigned int nr_writers;
 137
 138 pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
 139
 140 static
 141 void rcu_copy_mutex_lock(void)
 142 {
 143         int ret;
 144         ret = pthread_mutex_lock(&rcu_copy_mutex);
 145         if (ret) {
 146                 perror("Error in pthread mutex lock");
 147                 exit(-1);
 148         }
 149 }
 150
 151 static
 152 void rcu_copy_mutex_unlock(void)
 153 {
 154         int ret;
 155
 156         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 157         if (ret) {
 158                 perror("Error in pthread mutex unlock");
 159                 exit(-1);
 160         }
 161 }
 162
 163 /*
 164  * malloc/free are reusing memory areas too quickly, which does not let us
 165  * test races appropriately. Use a large circular array for allocations.
 166  * ARRAY_SIZE is larger than nr_writers, and we keep the mutex across
 167  * both alloc and free, which insures we never run over our tail.
 168  */
 169 #define ARRAY_SIZE (1048576 * nr_writers)
 170 #define ARRAY_POISON (int) 0xDEADBEEF
 171 static unsigned int array_index;
 172 static struct test_array *test_array;
 173
 174 static struct test_array *test_array_alloc(void)
 175 {
 176         struct test_array *ret;
 177         int index;
 178
 179         index = array_index % ARRAY_SIZE;
 180         assert(test_array[index].a == ARRAY_POISON ||
 181                 test_array[index].a == 0);
 182         ret = &test_array[index];
 183         array_index++;
 184         if (array_index == ARRAY_SIZE)
 185                 array_index = 0;
 186         return ret;
 187 }
 188
 189 static void test_array_free(struct test_array *ptr)
 190 {
 191         if (!ptr)
 192                 return;
 193         ptr->a = ARRAY_POISON;
 194 }
 195
 196 static
 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 static
 238 void *thr_writer(void *_count)
 239 {
 240         unsigned long long *count = _count;
 241         struct test_array *new, *old;
 242
 243         printf_verbose("thread_begin %s, tid %lu\n",
 244                         "writer", urcu_get_thread_id());
 245
 246         set_affinity();
 247
 248         while (!test_go)
 249         {
 250         }
 251         cmm_smp_mb();
 252
 253         for (;;) {
 254                 rcu_copy_mutex_lock();
 255                 new = test_array_alloc();
 256                 new->a = 8;
 257                 old = test_rcu_pointer;
 258                 rcu_assign_pointer(test_rcu_pointer, new);
 259                 if (caa_unlikely(wduration))
 260                         loop_sleep(wduration);
 261                 synchronize_rcu();
 262                 if (old)
 263                         old->a = 0;
 264                 test_array_free(old);
 265                 rcu_copy_mutex_unlock();
 266                 URCU_TLS(nr_writes)++;
 267                 if (caa_unlikely(!test_duration_write()))
 268                         break;
 269                 if (caa_unlikely(wdelay))
 270                         loop_sleep(wdelay);
 271         }
 272
 273         printf_verbose("thread_end %s, tid %lu\n",
 274                         "writer", urcu_get_thread_id());
 275         *count = URCU_TLS(nr_writes);
 276         return ((void*)2);
 277 }
 278
 279 static
 280 void show_usage(int argc, char **argv)
 281 {
 282         printf("Usage : %s nr_readers nr_writers duration (s) <OPTIONS>\n",
 283                 argv[0]);
 284         printf("OPTIONS:\n");
 285         printf("        [-r] [-w] (yield reader and/or writer)\n");
 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         unsigned int i_thr;
 303
 304         if (argc < 4) {
 305                 show_usage(argc, argv);
 306                 return -1;
 307         }
 308
 309         err = sscanf(argv[1], "%u", &nr_readers);
 310         if (err != 1) {
 311                 show_usage(argc, argv);
 312                 return -1;
 313         }
 314
 315         err = sscanf(argv[2], "%u", &nr_writers);
 316         if (err != 1) {
 317                 show_usage(argc, argv);
 318                 return -1;
 319         }
 320
 321         err = sscanf(argv[3], "%lu", &duration);
 322         if (err != 1) {
 323                 show_usage(argc, argv);
 324                 return -1;
 325         }
 326
 327         for (i = 4; i < argc; i++) {
 328                 if (argv[i][0] != '-')
 329                         continue;
 330                 switch (argv[i][1]) {
 331                 case 'r':
 332                         rcu_debug_yield_enable(RCU_YIELD_READ);
 333                         break;
 334                 case 'w':
 335                         rcu_debug_yield_enable(RCU_YIELD_WRITE);
 336                         break;
 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 'e':
 362                         if (argc < i + 2) {
 363                                 show_usage(argc, argv);
 364                                 return -1;
 365                         }
 366                         wduration = atol(argv[++i]);
 367                         break;
 368                 case 'v':
 369                         verbose_mode = 1;
 370                         break;
 371                 }
 372         }
 373
 374         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 375                 duration, nr_readers, nr_writers);
 376         printf_verbose("Writer delay : %lu loops.\n", wdelay);
 377         printf_verbose("Reader duration : %lu loops.\n", rduration);
 378         printf_verbose("thread %-6s, tid %lu\n",
 379                         "main", urcu_get_thread_id());
 380
 381         test_array = calloc(1, sizeof(*test_array) * ARRAY_SIZE);
 382         tid_reader = calloc(nr_readers, sizeof(*tid_reader));
 383         tid_writer = calloc(nr_writers, sizeof(*tid_writer));
 384         count_reader = calloc(nr_readers, sizeof(*count_reader));
 385         count_writer = calloc(nr_writers, sizeof(*count_writer));
 386
 387         next_aff = 0;
 388
 389         for (i_thr = 0; i_thr < nr_readers; i_thr++) {
 390                 err = pthread_create(&tid_reader[i_thr], NULL, thr_reader,
 391                                      &count_reader[i_thr]);
 392                 if (err != 0)
 393                         exit(1);
 394         }
 395         for (i_thr = 0; i_thr < nr_writers; i_thr++) {
 396                 err = pthread_create(&tid_writer[i_thr], NULL, thr_writer,
 397                                      &count_writer[i_thr]);
 398                 if (err != 0)
 399                         exit(1);
 400         }
 401
 402         cmm_smp_mb();
 403
 404         test_go = 1;
 405
 406         sleep(duration);
 407
 408         test_stop = 1;
 409
 410         for (i_thr = 0; i_thr < nr_readers; i_thr++) {
 411                 err = pthread_join(tid_reader[i_thr], &tret);
 412                 if (err != 0)
 413                         exit(1);
 414                 tot_reads += count_reader[i_thr];
 415         }
 416         for (i_thr = 0; i_thr < nr_writers; i_thr++) {
 417                 err = pthread_join(tid_writer[i_thr], &tret);
 418                 if (err != 0)
 419                         exit(1);
 420                 tot_writes += count_writer[i_thr];
 421         }
 422
 423         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 424                tot_writes);
 425         printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu wdur %6lu "
 426                 "nr_writers %3u "
 427                 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
 428                 argv[0], duration, nr_readers, rduration, wduration,
 429                 nr_writers, wdelay, tot_reads, tot_writes,
 430                 tot_reads + tot_writes);
 431
 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
 439         return 0;
 440 }