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