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 "thread-id.h"
  37 #include "../common/debug-yield.h"
  38
  39 /* hardcoded number of CPUs */
  40 #define NR_CPUS 16384
  41
  42 #ifndef DYNAMIC_LINK_TEST
  43 #define _LGPL_SOURCE
  44 #endif
  45 #include <urcu.h>
  46
  47 struct test_array {
  48         int a;
  49 };
  50
  51 static volatile int test_go, test_stop;
  52
  53 static unsigned long wdelay;
  54
  55 static struct test_array *test_rcu_pointer;
  56
  57 static unsigned long duration;
  58
  59 /* read-side C.S. duration, in loops */
  60 static unsigned long rduration;
  61
  62 /* write-side C.S. duration, in loops */
  63 static unsigned long wduration;
  64
  65 static inline void loop_sleep(unsigned long loops)
  66 {
  67         while (loops-- != 0)
  68                 caa_cpu_relax();
  69 }
  70
  71 static int verbose_mode;
  72
  73 #define printf_verbose(fmt, args...)            \
  74         do {                                    \
  75                 if (verbose_mode)               \
  76                         printf(fmt, args);      \
  77         } while (0)
  78
  79 static unsigned int cpu_affinities[NR_CPUS];
  80 static unsigned int next_aff = 0;
  81 static int use_affinity = 0;
  82
  83 pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
  84
  85 static void set_affinity(void)
  86 {
  87 #if HAVE_SCHED_SETAFFINITY
  88         cpu_set_t mask;
  89         int cpu, ret;
  90 #endif /* HAVE_SCHED_SETAFFINITY */
  91
  92         if (!use_affinity)
  93                 return;
  94
  95 #if HAVE_SCHED_SETAFFINITY
  96         ret = pthread_mutex_lock(&affinity_mutex);
  97         if (ret) {
  98                 perror("Error in pthread mutex lock");
  99                 exit(-1);
 100         }
 101         cpu = cpu_affinities[next_aff++];
 102         ret = pthread_mutex_unlock(&affinity_mutex);
 103         if (ret) {
 104                 perror("Error in pthread mutex unlock");
 105                 exit(-1);
 106         }
 107
 108         CPU_ZERO(&mask);
 109         CPU_SET(cpu, &mask);
 110         sched_setaffinity(0, sizeof(mask), &mask);
 111 #endif /* HAVE_SCHED_SETAFFINITY */
 112 }
 113
 114 /*
 115  * returns 0 if test should end.
 116  */
 117 static int test_duration_write(void)
 118 {
 119         return !test_stop;
 120 }
 121
 122 static int test_duration_read(void)
 123 {
 124         return !test_stop;
 125 }
 126
 127 static DEFINE_URCU_TLS(unsigned long long, nr_writes);
 128 static DEFINE_URCU_TLS(unsigned long long, nr_reads);
 129
 130 static unsigned int nr_readers;
 131 static unsigned int nr_writers;
 132
 133 pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
 134
 135 static
 136 void rcu_copy_mutex_lock(void)
 137 {
 138         int ret;
 139         ret = pthread_mutex_lock(&rcu_copy_mutex);
 140         if (ret) {
 141                 perror("Error in pthread mutex lock");
 142                 exit(-1);
 143         }
 144 }
 145
 146 static
 147 void rcu_copy_mutex_unlock(void)
 148 {
 149         int ret;
 150
 151         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 152         if (ret) {
 153                 perror("Error in pthread mutex unlock");
 154                 exit(-1);
 155         }
 156 }
 157
 158 /*
 159  * malloc/free are reusing memory areas too quickly, which does not let us
 160  * test races appropriately. Use a large circular array for allocations.
 161  * ARRAY_SIZE is larger than nr_writers, and we keep the mutex across
 162  * both alloc and free, which insures we never run over our tail.
 163  */
 164 #define ARRAY_SIZE (1048576 * nr_writers)
 165 #define ARRAY_POISON (int) 0xDEADBEEF
 166 static unsigned int array_index;
 167 static struct test_array *test_array;
 168
 169 static struct test_array *test_array_alloc(void)
 170 {
 171         struct test_array *ret;
 172         int index;
 173
 174         index = array_index % ARRAY_SIZE;
 175         assert(test_array[index].a == ARRAY_POISON ||
 176                 test_array[index].a == 0);
 177         ret = &test_array[index];
 178         array_index++;
 179         if (array_index == ARRAY_SIZE)
 180                 array_index = 0;
 181         return ret;
 182 }
 183
 184 static void test_array_free(struct test_array *ptr)
 185 {
 186         if (!ptr)
 187                 return;
 188         ptr->a = ARRAY_POISON;
 189 }
 190
 191 static
 192 void *thr_reader(void *_count)
 193 {
 194         unsigned long long *count = _count;
 195         struct test_array *local_ptr;
 196
 197         printf_verbose("thread_begin %s, tid %lu\n",
 198                         "reader", urcu_get_thread_id());
 199
 200         set_affinity();
 201
 202         rcu_register_thread();
 203
 204         while (!test_go)
 205         {
 206         }
 207         cmm_smp_mb();
 208
 209         for (;;) {
 210                 rcu_read_lock();
 211                 local_ptr = rcu_dereference(test_rcu_pointer);
 212                 rcu_debug_yield_read();
 213                 if (local_ptr)
 214                         assert(local_ptr->a == 8);
 215                 if (caa_unlikely(rduration))
 216                         loop_sleep(rduration);
 217                 rcu_read_unlock();
 218                 URCU_TLS(nr_reads)++;
 219                 if (caa_unlikely(!test_duration_read()))
 220                         break;
 221         }
 222
 223         rcu_unregister_thread();
 224
 225         *count = URCU_TLS(nr_reads);
 226         printf_verbose("thread_end %s, tid %lu\n",
 227                         "reader", urcu_get_thread_id());
 228         return ((void*)1);
 229
 230 }
 231
 232 static
 233 void *thr_writer(void *_count)
 234 {
 235         unsigned long long *count = _count;
 236         struct test_array *new, *old;
 237
 238         printf_verbose("thread_begin %s, tid %lu\n",
 239                         "writer", urcu_get_thread_id());
 240
 241         set_affinity();
 242
 243         while (!test_go)
 244         {
 245         }
 246         cmm_smp_mb();
 247
 248         for (;;) {
 249                 rcu_copy_mutex_lock();
 250                 new = test_array_alloc();
 251                 new->a = 8;
 252                 old = test_rcu_pointer;
 253                 rcu_assign_pointer(test_rcu_pointer, new);
 254                 if (caa_unlikely(wduration))
 255                         loop_sleep(wduration);
 256                 synchronize_rcu();
 257                 if (old)
 258                         old->a = 0;
 259                 test_array_free(old);
 260                 rcu_copy_mutex_unlock();
 261                 URCU_TLS(nr_writes)++;
 262                 if (caa_unlikely(!test_duration_write()))
 263                         break;
 264                 if (caa_unlikely(wdelay))
 265                         loop_sleep(wdelay);
 266         }
 267
 268         printf_verbose("thread_end %s, tid %lu\n",
 269                         "writer", urcu_get_thread_id());
 270         *count = URCU_TLS(nr_writes);
 271         return ((void*)2);
 272 }
 273
 274 static
 275 void show_usage(int argc, char **argv)
 276 {
 277         printf("Usage : %s nr_readers nr_writers duration (s) <OPTIONS>\n",
 278                 argv[0]);
 279         printf("OPTIONS:\n");
 280         printf("        [-r] [-w] (yield reader and/or writer)\n");
 281         printf("        [-d delay] (writer period (us))\n");
 282         printf("        [-c duration] (reader C.S. duration (in loops))\n");
 283         printf("        [-e duration] (writer C.S. duration (in loops))\n");
 284         printf("        [-v] (verbose output)\n");
 285         printf("        [-a cpu#] [-a cpu#]... (affinity)\n");
 286         printf("\n");
 287 }
 288
 289 int main(int argc, char **argv)
 290 {
 291         int err;
 292         pthread_t *tid_reader, *tid_writer;
 293         void *tret;
 294         unsigned long long *count_reader, *count_writer;
 295         unsigned long long tot_reads = 0, tot_writes = 0;
 296         int i, a;
 297         unsigned int i_thr;
 298
 299         if (argc < 4) {
 300                 show_usage(argc, argv);
 301                 return -1;
 302         }
 303
 304         err = sscanf(argv[1], "%u", &nr_readers);
 305         if (err != 1) {
 306                 show_usage(argc, argv);
 307                 return -1;
 308         }
 309
 310         err = sscanf(argv[2], "%u", &nr_writers);
 311         if (err != 1) {
 312                 show_usage(argc, argv);
 313                 return -1;
 314         }
 315
 316         err = sscanf(argv[3], "%lu", &duration);
 317         if (err != 1) {
 318                 show_usage(argc, argv);
 319                 return -1;
 320         }
 321
 322         for (i = 4; i < argc; i++) {
 323                 if (argv[i][0] != '-')
 324                         continue;
 325                 switch (argv[i][1]) {
 326                 case 'r':
 327                         rcu_debug_yield_enable(RCU_YIELD_READ);
 328                         break;
 329                 case 'w':
 330                         rcu_debug_yield_enable(RCU_YIELD_WRITE);
 331                         break;
 332                 case 'a':
 333                         if (argc < i + 2) {
 334                                 show_usage(argc, argv);
 335                                 return -1;
 336                         }
 337                         a = atoi(argv[++i]);
 338                         cpu_affinities[next_aff++] = a;
 339                         use_affinity = 1;
 340                         printf_verbose("Adding CPU %d affinity\n", a);
 341                         break;
 342                 case 'c':
 343                         if (argc < i + 2) {
 344                                 show_usage(argc, argv);
 345                                 return -1;
 346                         }
 347                         rduration = atol(argv[++i]);
 348                         break;
 349                 case 'd':
 350                         if (argc < i + 2) {
 351                                 show_usage(argc, argv);
 352                                 return -1;
 353                         }
 354                         wdelay = atol(argv[++i]);
 355                         break;
 356                 case 'e':
 357                         if (argc < i + 2) {
 358                                 show_usage(argc, argv);
 359                                 return -1;
 360                         }
 361                         wduration = atol(argv[++i]);
 362                         break;
 363                 case 'v':
 364                         verbose_mode = 1;
 365                         break;
 366                 }
 367         }
 368
 369         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 370                 duration, nr_readers, nr_writers);
 371         printf_verbose("Writer delay : %lu loops.\n", wdelay);
 372         printf_verbose("Reader duration : %lu loops.\n", rduration);
 373         printf_verbose("thread %-6s, tid %lu\n",
 374                         "main", urcu_get_thread_id());
 375
 376         test_array = calloc(1, sizeof(*test_array) * ARRAY_SIZE);
 377         tid_reader = calloc(nr_readers, sizeof(*tid_reader));
 378         tid_writer = calloc(nr_writers, sizeof(*tid_writer));
 379         count_reader = calloc(nr_readers, sizeof(*count_reader));
 380         count_writer = calloc(nr_writers, sizeof(*count_writer));
 381
 382         next_aff = 0;
 383
 384         for (i_thr = 0; i_thr < nr_readers; i_thr++) {
 385                 err = pthread_create(&tid_reader[i_thr], NULL, thr_reader,
 386                                      &count_reader[i_thr]);
 387                 if (err != 0)
 388                         exit(1);
 389         }
 390         for (i_thr = 0; i_thr < nr_writers; i_thr++) {
 391                 err = pthread_create(&tid_writer[i_thr], NULL, thr_writer,
 392                                      &count_writer[i_thr]);
 393                 if (err != 0)
 394                         exit(1);
 395         }
 396
 397         cmm_smp_mb();
 398
 399         test_go = 1;
 400
 401         sleep(duration);
 402
 403         test_stop = 1;
 404
 405         for (i_thr = 0; i_thr < nr_readers; i_thr++) {
 406                 err = pthread_join(tid_reader[i_thr], &tret);
 407                 if (err != 0)
 408                         exit(1);
 409                 tot_reads += count_reader[i_thr];
 410         }
 411         for (i_thr = 0; i_thr < nr_writers; i_thr++) {
 412                 err = pthread_join(tid_writer[i_thr], &tret);
 413                 if (err != 0)
 414                         exit(1);
 415                 tot_writes += count_writer[i_thr];
 416         }
 417
 418         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 419                tot_writes);
 420         printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu wdur %6lu "
 421                 "nr_writers %3u "
 422                 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
 423                 argv[0], duration, nr_readers, rduration, wduration,
 424                 nr_writers, wdelay, tot_reads, tot_writes,
 425                 tot_reads + tot_writes);
 426
 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
 434         return 0;
 435 }