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 void rcu_copy_mutex_lock(void)
 136 {
 137         int ret;
 138         ret = pthread_mutex_lock(&rcu_copy_mutex);
 139         if (ret) {
 140                 perror("Error in pthread mutex lock");
 141                 exit(-1);
 142         }
 143 }
 144
 145 void rcu_copy_mutex_unlock(void)
 146 {
 147         int ret;
 148
 149         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 150         if (ret) {
 151                 perror("Error in pthread mutex unlock");
 152                 exit(-1);
 153         }
 154 }
 155
 156 /*
 157  * malloc/free are reusing memory areas too quickly, which does not let us
 158  * test races appropriately. Use a large circular array for allocations.
 159  * ARRAY_SIZE is larger than nr_writers, and we keep the mutex across
 160  * both alloc and free, which insures we never run over our tail.
 161  */
 162 #define ARRAY_SIZE (1048576 * nr_writers)
 163 #define ARRAY_POISON (int) 0xDEADBEEF
 164 static unsigned int array_index;
 165 static struct test_array *test_array;
 166
 167 static struct test_array *test_array_alloc(void)
 168 {
 169         struct test_array *ret;
 170         int index;
 171
 172         index = array_index % ARRAY_SIZE;
 173         assert(test_array[index].a == ARRAY_POISON ||
 174                 test_array[index].a == 0);
 175         ret = &test_array[index];
 176         array_index++;
 177         if (array_index == ARRAY_SIZE)
 178                 array_index = 0;
 179         return ret;
 180 }
 181
 182 static void test_array_free(struct test_array *ptr)
 183 {
 184         if (!ptr)
 185                 return;
 186         ptr->a = ARRAY_POISON;
 187 }
 188
 189 void *thr_reader(void *_count)
 190 {
 191         unsigned long long *count = _count;
 192         struct test_array *local_ptr;
 193
 194         printf_verbose("thread_begin %s, tid %lu\n",
 195                         "reader", urcu_get_thread_id());
 196
 197         set_affinity();
 198
 199         rcu_register_thread();
 200
 201         while (!test_go)
 202         {
 203         }
 204         cmm_smp_mb();
 205
 206         for (;;) {
 207                 rcu_read_lock();
 208                 local_ptr = rcu_dereference(test_rcu_pointer);
 209                 rcu_debug_yield_read();
 210                 if (local_ptr)
 211                         assert(local_ptr->a == 8);
 212                 if (caa_unlikely(rduration))
 213                         loop_sleep(rduration);
 214                 rcu_read_unlock();
 215                 URCU_TLS(nr_reads)++;
 216                 if (caa_unlikely(!test_duration_read()))
 217                         break;
 218         }
 219
 220         rcu_unregister_thread();
 221
 222         *count = URCU_TLS(nr_reads);
 223         printf_verbose("thread_end %s, tid %lu\n",
 224                         "reader", urcu_get_thread_id());
 225         return ((void*)1);
 226
 227 }
 228
 229 void *thr_writer(void *_count)
 230 {
 231         unsigned long long *count = _count;
 232         struct test_array *new, *old;
 233
 234         printf_verbose("thread_begin %s, tid %lu\n",
 235                         "writer", urcu_get_thread_id());
 236
 237         set_affinity();
 238
 239         while (!test_go)
 240         {
 241         }
 242         cmm_smp_mb();
 243
 244         for (;;) {
 245                 rcu_copy_mutex_lock();
 246                 new = test_array_alloc();
 247                 new->a = 8;
 248                 old = test_rcu_pointer;
 249                 rcu_assign_pointer(test_rcu_pointer, new);
 250                 if (caa_unlikely(wduration))
 251                         loop_sleep(wduration);
 252                 synchronize_rcu();
 253                 if (old)
 254                         old->a = 0;
 255                 test_array_free(old);
 256                 rcu_copy_mutex_unlock();
 257                 URCU_TLS(nr_writes)++;
 258                 if (caa_unlikely(!test_duration_write()))
 259                         break;
 260                 if (caa_unlikely(wdelay))
 261                         loop_sleep(wdelay);
 262         }
 263
 264         printf_verbose("thread_end %s, tid %lu\n",
 265                         "writer", urcu_get_thread_id());
 266         *count = URCU_TLS(nr_writes);
 267         return ((void*)2);
 268 }
 269
 270 void show_usage(int argc, char **argv)
 271 {
 272         printf("Usage : %s nr_readers nr_writers duration (s) <OPTIONS>\n",
 273                 argv[0]);
 274         printf("OPTIONS:\n");
 275         printf("        [-r] [-w] (yield reader and/or writer)\n");
 276         printf("        [-d delay] (writer period (us))\n");
 277         printf("        [-c duration] (reader C.S. duration (in loops))\n");
 278         printf("        [-e duration] (writer C.S. duration (in loops))\n");
 279         printf("        [-v] (verbose output)\n");
 280         printf("        [-a cpu#] [-a cpu#]... (affinity)\n");
 281         printf("\n");
 282 }
 283
 284 int main(int argc, char **argv)
 285 {
 286         int err;
 287         pthread_t *tid_reader, *tid_writer;
 288         void *tret;
 289         unsigned long long *count_reader, *count_writer;
 290         unsigned long long tot_reads = 0, tot_writes = 0;
 291         int i, a;
 292         unsigned int i_thr;
 293
 294         if (argc < 4) {
 295                 show_usage(argc, argv);
 296                 return -1;
 297         }
 298
 299         err = sscanf(argv[1], "%u", &nr_readers);
 300         if (err != 1) {
 301                 show_usage(argc, argv);
 302                 return -1;
 303         }
 304
 305         err = sscanf(argv[2], "%u", &nr_writers);
 306         if (err != 1) {
 307                 show_usage(argc, argv);
 308                 return -1;
 309         }
 310
 311         err = sscanf(argv[3], "%lu", &duration);
 312         if (err != 1) {
 313                 show_usage(argc, argv);
 314                 return -1;
 315         }
 316
 317         for (i = 4; i < argc; i++) {
 318                 if (argv[i][0] != '-')
 319                         continue;
 320                 switch (argv[i][1]) {
 321                 case 'r':
 322                         rcu_debug_yield_enable(RCU_YIELD_READ);
 323                         break;
 324                 case 'w':
 325                         rcu_debug_yield_enable(RCU_YIELD_WRITE);
 326                         break;
 327                 case 'a':
 328                         if (argc < i + 2) {
 329                                 show_usage(argc, argv);
 330                                 return -1;
 331                         }
 332                         a = atoi(argv[++i]);
 333                         cpu_affinities[next_aff++] = a;
 334                         use_affinity = 1;
 335                         printf_verbose("Adding CPU %d affinity\n", a);
 336                         break;
 337                 case 'c':
 338                         if (argc < i + 2) {
 339                                 show_usage(argc, argv);
 340                                 return -1;
 341                         }
 342                         rduration = atol(argv[++i]);
 343                         break;
 344                 case 'd':
 345                         if (argc < i + 2) {
 346                                 show_usage(argc, argv);
 347                                 return -1;
 348                         }
 349                         wdelay = atol(argv[++i]);
 350                         break;
 351                 case 'e':
 352                         if (argc < i + 2) {
 353                                 show_usage(argc, argv);
 354                                 return -1;
 355                         }
 356                         wduration = atol(argv[++i]);
 357                         break;
 358                 case 'v':
 359                         verbose_mode = 1;
 360                         break;
 361                 }
 362         }
 363
 364         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 365                 duration, nr_readers, nr_writers);
 366         printf_verbose("Writer delay : %lu loops.\n", wdelay);
 367         printf_verbose("Reader duration : %lu loops.\n", rduration);
 368         printf_verbose("thread %-6s, tid %lu\n",
 369                         "main", urcu_get_thread_id());
 370
 371         test_array = calloc(1, sizeof(*test_array) * ARRAY_SIZE);
 372         tid_reader = calloc(nr_readers, sizeof(*tid_reader));
 373         tid_writer = calloc(nr_writers, sizeof(*tid_writer));
 374         count_reader = calloc(nr_readers, sizeof(*count_reader));
 375         count_writer = calloc(nr_writers, sizeof(*count_writer));
 376
 377         next_aff = 0;
 378
 379         for (i_thr = 0; i_thr < nr_readers; i_thr++) {
 380                 err = pthread_create(&tid_reader[i_thr], NULL, thr_reader,
 381                                      &count_reader[i_thr]);
 382                 if (err != 0)
 383                         exit(1);
 384         }
 385         for (i_thr = 0; i_thr < nr_writers; i_thr++) {
 386                 err = pthread_create(&tid_writer[i_thr], NULL, thr_writer,
 387                                      &count_writer[i_thr]);
 388                 if (err != 0)
 389                         exit(1);
 390         }
 391
 392         cmm_smp_mb();
 393
 394         test_go = 1;
 395
 396         sleep(duration);
 397
 398         test_stop = 1;
 399
 400         for (i_thr = 0; i_thr < nr_readers; i_thr++) {
 401                 err = pthread_join(tid_reader[i_thr], &tret);
 402                 if (err != 0)
 403                         exit(1);
 404                 tot_reads += count_reader[i_thr];
 405         }
 406         for (i_thr = 0; i_thr < nr_writers; i_thr++) {
 407                 err = pthread_join(tid_writer[i_thr], &tret);
 408                 if (err != 0)
 409                         exit(1);
 410                 tot_writes += count_writer[i_thr];
 411         }
 412
 413         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 414                tot_writes);
 415         printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu wdur %6lu "
 416                 "nr_writers %3u "
 417                 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
 418                 argv[0], duration, nr_readers, rduration, wduration,
 419                 nr_writers, wdelay, tot_reads, tot_writes,
 420                 tot_reads + tot_writes);
 421
 422         test_array_free(test_rcu_pointer);
 423         free(test_array);
 424         free(tid_reader);
 425         free(tid_writer);
 426         free(count_reader);
 427         free(count_writer);
 428
 429         return 0;
 430 }