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 void rcu_copy_mutex_lock(void)
 141 {
 142         int ret;
 143         ret = pthread_mutex_lock(&rcu_copy_mutex);
 144         if (ret) {
 145                 perror("Error in pthread mutex lock");
 146                 exit(-1);
 147         }
 148 }
 149
 150 void rcu_copy_mutex_unlock(void)
 151 {
 152         int ret;
 153
 154         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 155         if (ret) {
 156                 perror("Error in pthread mutex unlock");
 157                 exit(-1);
 158         }
 159 }
 160
 161 /*
 162  * malloc/free are reusing memory areas too quickly, which does not let us
 163  * test races appropriately. Use a large circular array for allocations.
 164  * ARRAY_SIZE is larger than nr_writers, and we keep the mutex across
 165  * both alloc and free, which insures we never run over our tail.
 166  */
 167 #define ARRAY_SIZE (1048576 * nr_writers)
 168 #define ARRAY_POISON 0xDEADBEEF
 169 static int array_index;
 170 static struct test_array *test_array;
 171
 172 static struct test_array *test_array_alloc(void)
 173 {
 174         struct test_array *ret;
 175         int index;
 176
 177         index = array_index % ARRAY_SIZE;
 178         assert(test_array[index].a == ARRAY_POISON ||
 179                 test_array[index].a == 0);
 180         ret = &test_array[index];
 181         array_index++;
 182         if (array_index == ARRAY_SIZE)
 183                 array_index = 0;
 184         return ret;
 185 }
 186
 187 static void test_array_free(struct test_array *ptr)
 188 {
 189         if (!ptr)
 190                 return;
 191         ptr->a = ARRAY_POISON;
 192 }
 193
 194 void *thr_reader(void *_count)
 195 {
 196         unsigned long long *count = _count;
 197         struct test_array *local_ptr;
 198
 199         printf_verbose("thread_begin %s, tid %lu\n",
 200                         "reader", urcu_get_thread_id());
 201
 202         set_affinity();
 203
 204         rcu_register_thread();
 205
 206         while (!test_go)
 207         {
 208         }
 209         cmm_smp_mb();
 210
 211         for (;;) {
 212                 rcu_read_lock();
 213                 local_ptr = rcu_dereference(test_rcu_pointer);
 214                 rcu_debug_yield_read();
 215                 if (local_ptr)
 216                         assert(local_ptr->a == 8);
 217                 if (caa_unlikely(rduration))
 218                         loop_sleep(rduration);
 219                 rcu_read_unlock();
 220                 URCU_TLS(nr_reads)++;
 221                 if (caa_unlikely(!test_duration_read()))
 222                         break;
 223         }
 224
 225         rcu_unregister_thread();
 226
 227         *count = URCU_TLS(nr_reads);
 228         printf_verbose("thread_end %s, tid %lu\n",
 229                         "reader", urcu_get_thread_id());
 230         return ((void*)1);
 231
 232 }
 233
 234 void *thr_writer(void *_count)
 235 {
 236         unsigned long long *count = _count;
 237         struct test_array *new, *old;
 238
 239         printf_verbose("thread_begin %s, tid %lu\n",
 240                         "writer", urcu_get_thread_id());
 241
 242         set_affinity();
 243
 244         while (!test_go)
 245         {
 246         }
 247         cmm_smp_mb();
 248
 249         for (;;) {
 250                 rcu_copy_mutex_lock();
 251                 new = test_array_alloc();
 252                 new->a = 8;
 253                 old = test_rcu_pointer;
 254                 rcu_assign_pointer(test_rcu_pointer, new);
 255                 if (caa_unlikely(wduration))
 256                         loop_sleep(wduration);
 257                 synchronize_rcu();
 258                 if (old)
 259                         old->a = 0;
 260                 test_array_free(old);
 261                 rcu_copy_mutex_unlock();
 262                 URCU_TLS(nr_writes)++;
 263                 if (caa_unlikely(!test_duration_write()))
 264                         break;
 265                 if (caa_unlikely(wdelay))
 266                         loop_sleep(wdelay);
 267         }
 268
 269         printf_verbose("thread_end %s, tid %lu\n",
 270                         "writer", urcu_get_thread_id());
 271         *count = URCU_TLS(nr_writes);
 272         return ((void*)2);
 273 }
 274
 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
 298         if (argc < 4) {
 299                 show_usage(argc, argv);
 300                 return -1;
 301         }
 302
 303         err = sscanf(argv[1], "%u", &nr_readers);
 304         if (err != 1) {
 305                 show_usage(argc, argv);
 306                 return -1;
 307         }
 308
 309         err = sscanf(argv[2], "%u", &nr_writers);
 310         if (err != 1) {
 311                 show_usage(argc, argv);
 312                 return -1;
 313         }
 314
 315         err = sscanf(argv[3], "%lu", &duration);
 316         if (err != 1) {
 317                 show_usage(argc, argv);
 318                 return -1;
 319         }
 320
 321         for (i = 4; i < argc; i++) {
 322                 if (argv[i][0] != '-')
 323                         continue;
 324                 switch (argv[i][1]) {
 325                 case 'r':
 326                         rcu_debug_yield_enable(RCU_YIELD_READ);
 327                         break;
 328                 case 'w':
 329                         rcu_debug_yield_enable(RCU_YIELD_WRITE);
 330                         break;
 331                 case 'a':
 332                         if (argc < i + 2) {
 333                                 show_usage(argc, argv);
 334                                 return -1;
 335                         }
 336                         a = atoi(argv[++i]);
 337                         cpu_affinities[next_aff++] = a;
 338                         use_affinity = 1;
 339                         printf_verbose("Adding CPU %d affinity\n", a);
 340                         break;
 341                 case 'c':
 342                         if (argc < i + 2) {
 343                                 show_usage(argc, argv);
 344                                 return -1;
 345                         }
 346                         rduration = atol(argv[++i]);
 347                         break;
 348                 case 'd':
 349                         if (argc < i + 2) {
 350                                 show_usage(argc, argv);
 351                                 return -1;
 352                         }
 353                         wdelay = atol(argv[++i]);
 354                         break;
 355                 case 'e':
 356                         if (argc < i + 2) {
 357                                 show_usage(argc, argv);
 358                                 return -1;
 359                         }
 360                         wduration = atol(argv[++i]);
 361                         break;
 362                 case 'v':
 363                         verbose_mode = 1;
 364                         break;
 365                 }
 366         }
 367
 368         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 369                 duration, nr_readers, nr_writers);
 370         printf_verbose("Writer delay : %lu loops.\n", wdelay);
 371         printf_verbose("Reader duration : %lu loops.\n", rduration);
 372         printf_verbose("thread %-6s, tid %lu\n",
 373                         "main", urcu_get_thread_id());
 374
 375         test_array = calloc(1, sizeof(*test_array) * ARRAY_SIZE);
 376         tid_reader = calloc(nr_readers, sizeof(*tid_reader));
 377         tid_writer = calloc(nr_writers, sizeof(*tid_writer));
 378         count_reader = calloc(nr_readers, sizeof(*count_reader));
 379         count_writer = calloc(nr_writers, sizeof(*count_writer));
 380
 381         next_aff = 0;
 382
 383         for (i = 0; i < nr_readers; i++) {
 384                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 385                                      &count_reader[i]);
 386                 if (err != 0)
 387                         exit(1);
 388         }
 389         for (i = 0; i < nr_writers; i++) {
 390                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 391                                      &count_writer[i]);
 392                 if (err != 0)
 393                         exit(1);
 394         }
 395
 396         cmm_smp_mb();
 397
 398         test_go = 1;
 399
 400         sleep(duration);
 401
 402         test_stop = 1;
 403
 404         for (i = 0; i < nr_readers; i++) {
 405                 err = pthread_join(tid_reader[i], &tret);
 406                 if (err != 0)
 407                         exit(1);
 408                 tot_reads += count_reader[i];
 409         }
 410         for (i = 0; i < nr_writers; i++) {
 411                 err = pthread_join(tid_writer[i], &tret);
 412                 if (err != 0)
 413                         exit(1);
 414                 tot_writes += count_writer[i];
 415         }
 416
 417         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 418                tot_writes);
 419         printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu wdur %6lu "
 420                 "nr_writers %3u "
 421                 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
 422                 argv[0], duration, nr_readers, rduration, wduration,
 423                 nr_writers, wdelay, tot_reads, tot_writes,
 424                 tot_reads + tot_writes);
 425         test_array_free(test_rcu_pointer);
 426         free(test_array);
 427         free(tid_reader);
 428         free(tid_writer);
 429         free(count_reader);
 430         free(count_writer);
 431         return 0;
 432 }