tests/test_urcu_hash.c

   1 /*
   2  * test_urcu_hash.c
   3  *
   4  * Userspace RCU library - test program
   5  *
   6  * Copyright 2009-2012 - Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
   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 "test_urcu_hash.h"
  25
  26 enum test_hash {
  27         TEST_HASH_RW,
  28         TEST_HASH_UNIQUE,
  29 };
  30
  31 struct test_hash_cb {
  32         void (*sigusr1)(int signo);
  33         void (*sigusr2)(int signo);
  34         void *(*thr_reader)(void *_count);
  35         void *(*thr_writer)(void *_count);
  36         int (*populate_hash)(void);
  37 };
  38
  39 static
  40 struct test_hash_cb test_hash_cb[] = {
  41         [TEST_HASH_RW] = {
  42                 test_hash_rw_sigusr1_handler,
  43                 test_hash_rw_sigusr2_handler,
  44                 test_hash_rw_thr_reader,
  45                 test_hash_rw_thr_writer,
  46                 test_hash_rw_populate_hash,
  47         },
  48         [TEST_HASH_UNIQUE] = {
  49                 test_hash_unique_sigusr1_handler,
  50                 test_hash_unique_sigusr2_handler,
  51                 test_hash_unique_thr_reader,
  52                 test_hash_unique_thr_writer,
  53                 test_hash_unique_populate_hash,
  54         },
  55
  56 };
  57
  58 static enum test_hash test_choice = TEST_HASH_RW;
  59
  60 void (*get_sigusr1_cb(void))(int)
  61 {
  62         return test_hash_cb[test_choice].sigusr1;
  63 }
  64
  65 void (*get_sigusr2_cb(void))(int)
  66 {
  67         return test_hash_cb[test_choice].sigusr2;
  68 }
  69
  70 void *(*get_thr_reader_cb(void))(void *)
  71 {
  72         return test_hash_cb[test_choice].thr_reader;
  73 }
  74
  75 void *(*get_thr_writer_cb(void))(void *)
  76 {
  77         return test_hash_cb[test_choice].thr_writer;
  78 }
  79
  80 int (*get_populate_hash_cb(void))(void)
  81 {
  82         return test_hash_cb[test_choice].populate_hash;
  83 }
  84
  85 unsigned int __thread rand_lookup;
  86 unsigned long __thread nr_add;
  87 unsigned long __thread nr_addexist;
  88 unsigned long __thread nr_del;
  89 unsigned long __thread nr_delnoent;
  90 unsigned long __thread lookup_fail;
  91 unsigned long __thread lookup_ok;
  92
  93 struct cds_lfht *test_ht;
  94
  95 volatile int test_go, test_stop;
  96
  97 unsigned long wdelay;
  98
  99 unsigned long duration;
 100
 101 /* read-side C.S. duration, in loops */
 102 unsigned long rduration;
 103
 104 unsigned long init_hash_size = DEFAULT_HASH_SIZE;
 105 unsigned long min_hash_alloc_size = DEFAULT_MIN_ALLOC_SIZE;
 106 unsigned long max_hash_buckets_size = (1UL << 20);
 107 unsigned long init_populate;
 108 int opt_auto_resize;
 109 int add_only, add_unique, add_replace;
 110 const struct cds_lfht_mm_type *memory_backend;
 111
 112 unsigned long init_pool_offset, lookup_pool_offset, write_pool_offset;
 113 unsigned long init_pool_size = DEFAULT_RAND_POOL,
 114         lookup_pool_size = DEFAULT_RAND_POOL,
 115         write_pool_size = DEFAULT_RAND_POOL;
 116 int validate_lookup;
 117
 118 int count_pipe[2];
 119
 120 int verbose_mode;
 121
 122 unsigned int cpu_affinities[NR_CPUS];
 123 unsigned int next_aff = 0;
 124 int use_affinity = 0;
 125
 126 pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
 127
 128 unsigned long long __thread nr_writes;
 129 unsigned long long __thread nr_reads;
 130
 131 unsigned int nr_readers;
 132 unsigned int nr_writers;
 133
 134 static pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
 135
 136 void set_affinity(void)
 137 {
 138         cpu_set_t mask;
 139         int cpu;
 140         int ret;
 141
 142         if (!use_affinity)
 143                 return;
 144
 145 #if HAVE_SCHED_SETAFFINITY
 146         ret = pthread_mutex_lock(&affinity_mutex);
 147         if (ret) {
 148                 perror("Error in pthread mutex lock");
 149                 exit(-1);
 150         }
 151         cpu = cpu_affinities[next_aff++];
 152         ret = pthread_mutex_unlock(&affinity_mutex);
 153         if (ret) {
 154                 perror("Error in pthread mutex unlock");
 155                 exit(-1);
 156         }
 157         CPU_ZERO(&mask);
 158         CPU_SET(cpu, &mask);
 159 #if SCHED_SETAFFINITY_ARGS == 2
 160         sched_setaffinity(0, &mask);
 161 #else
 162         sched_setaffinity(0, sizeof(mask), &mask);
 163 #endif
 164 #endif /* HAVE_SCHED_SETAFFINITY */
 165 }
 166
 167 void rcu_copy_mutex_lock(void)
 168 {
 169         int ret;
 170         ret = pthread_mutex_lock(&rcu_copy_mutex);
 171         if (ret) {
 172                 perror("Error in pthread mutex lock");
 173                 exit(-1);
 174         }
 175 }
 176
 177 void rcu_copy_mutex_unlock(void)
 178 {
 179         int ret;
 180
 181         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 182         if (ret) {
 183                 perror("Error in pthread mutex unlock");
 184                 exit(-1);
 185         }
 186 }
 187
 188 unsigned long test_compare(const void *key1, size_t key1_len,
 189                            const void *key2, size_t key2_len)
 190 {
 191         if (caa_unlikely(key1_len != key2_len))
 192                 return -1;
 193         assert(key1_len == sizeof(unsigned long));
 194         if (key1 == key2)
 195                 return 0;
 196         else
 197                 return 1;
 198 }
 199
 200 void *thr_count(void *arg)
 201 {
 202         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 203                         "counter", pthread_self(), (unsigned long)gettid());
 204
 205         rcu_register_thread();
 206
 207         for (;;) {
 208                 unsigned long count;
 209                 long approx_before, approx_after;
 210                 ssize_t len;
 211                 char buf[1];
 212
 213                 rcu_thread_offline();
 214                 len = read(count_pipe[0], buf, 1);
 215                 rcu_thread_online();
 216                 if (caa_unlikely(!test_duration_read()))
 217                         break;
 218                 if (len != 1)
 219                         continue;
 220                 /* Accounting */
 221                 printf("Counting nodes... ");
 222                 fflush(stdout);
 223                 rcu_read_lock();
 224                 cds_lfht_count_nodes(test_ht, &approx_before, &count,
 225                                 &approx_after);
 226                 rcu_read_unlock();
 227                 printf("done.\n");
 228                 printf("Approximation before node accounting: %ld nodes.\n",
 229                         approx_before);
 230                 printf("Accounting of nodes in the hash table: "
 231                         "%lu nodes.\n",
 232                         count);
 233                 printf("Approximation after node accounting: %ld nodes.\n",
 234                         approx_after);
 235         }
 236         rcu_unregister_thread();
 237         return NULL;
 238 }
 239
 240 void free_node_cb(struct rcu_head *head)
 241 {
 242         struct lfht_test_node *node =
 243                 caa_container_of(head, struct lfht_test_node, head);
 244         free(node);
 245 }
 246
 247 static
 248 void test_delete_all_nodes(struct cds_lfht *ht)
 249 {
 250         struct cds_lfht_iter iter;
 251         struct lfht_test_node *node;
 252         unsigned long count = 0;
 253
 254         cds_lfht_for_each_entry(ht, &iter, node, node) {
 255                 int ret;
 256
 257                 ret = cds_lfht_del(test_ht, cds_lfht_iter_get_node(&iter));
 258                 assert(!ret);
 259                 call_rcu(&node->head, free_node_cb);
 260                 count++;
 261         }
 262         printf("deleted %lu nodes.\n", count);
 263 }
 264
 265 void show_usage(int argc, char **argv)
 266 {
 267         printf("Usage : %s nr_readers nr_writers duration (s)\n", argv[0]);
 268 #ifdef DEBUG_YIELD
 269         printf("        [-r] [-w] (yield reader and/or writer)\n");
 270 #endif
 271         printf("        [-d delay] (writer period (us))\n");
 272         printf("        [-c duration] (reader C.S. duration (in loops))\n");
 273         printf("        [-v] (verbose output)\n");
 274         printf("        [-a cpu#] [-a cpu#]... (affinity)\n");
 275         printf("        [-h size] (initial number of buckets)\n");
 276         printf("        [-m size] (minimum number of allocated buckets)\n");
 277         printf("        [-n size] (maximum number of buckets)\n");
 278 printf("        [not -u nor -s] Add entries (supports redundant keys).\n");
 279         printf("        [-u] Uniquify add (no redundant keys).\n");
 280         printf("        [-s] Replace (swap) entries.\n");
 281         printf("        [-i] Add only (no removal).\n");
 282         printf("        [-k nr_nodes] Number of nodes to insert initially.\n");
 283         printf("        [-A] Automatically resize hash table.\n");
 284         printf("        [-B order|chunk|mmap] Specify the memory backend.\n");
 285         printf("        [-R offset] Lookup pool offset.\n");
 286         printf("        [-S offset] Write pool offset.\n");
 287         printf("        [-T offset] Init pool offset.\n");
 288         printf("        [-M size] Lookup pool size.\n");
 289         printf("        [-N size] Write pool size.\n");
 290         printf("        [-O size] Init pool size.\n");
 291         printf("        [-V] Validate lookups of init values (use with filled init pool, same lookup range, with different write range).\n");
 292         printf("        [-U] Uniqueness test.\n");
 293         printf("\n\n");
 294 }
 295
 296 int main(int argc, char **argv)
 297 {
 298         int err;
 299         pthread_t *tid_reader, *tid_writer;
 300         pthread_t tid_count;
 301         void *tret;
 302         unsigned long long *count_reader;
 303         struct wr_count *count_writer;
 304         unsigned long long tot_reads = 0, tot_writes = 0,
 305                 tot_add = 0, tot_add_exist = 0, tot_remove = 0;
 306         unsigned long count;
 307         long approx_before, approx_after;
 308         int i, a, ret;
 309         struct sigaction act;
 310         unsigned int remain;
 311
 312         if (argc < 4) {
 313                 show_usage(argc, argv);
 314                 return -1;
 315         }
 316
 317         err = sscanf(argv[1], "%u", &nr_readers);
 318         if (err != 1) {
 319                 show_usage(argc, argv);
 320                 return -1;
 321         }
 322
 323         err = sscanf(argv[2], "%u", &nr_writers);
 324         if (err != 1) {
 325                 show_usage(argc, argv);
 326                 return -1;
 327         }
 328
 329         err = sscanf(argv[3], "%lu", &duration);
 330         if (err != 1) {
 331                 show_usage(argc, argv);
 332                 return -1;
 333         }
 334
 335         for (i = 4; i < argc; i++) {
 336                 if (argv[i][0] != '-')
 337                         continue;
 338                 switch (argv[i][1]) {
 339 #ifdef DEBUG_YIELD
 340                 case 'r':
 341                         yield_active |= YIELD_READ;
 342                         break;
 343                 case 'w':
 344                         yield_active |= YIELD_WRITE;
 345                         break;
 346 #endif
 347                 case 'a':
 348                         if (argc < i + 2) {
 349                                 show_usage(argc, argv);
 350                                 return -1;
 351                         }
 352                         a = atoi(argv[++i]);
 353                         cpu_affinities[next_aff++] = a;
 354                         use_affinity = 1;
 355                         printf_verbose("Adding CPU %d affinity\n", a);
 356                         break;
 357                 case 'c':
 358                         if (argc < i + 2) {
 359                                 show_usage(argc, argv);
 360                                 return -1;
 361                         }
 362                         rduration = atol(argv[++i]);
 363                         break;
 364                 case 'd':
 365                         if (argc < i + 2) {
 366                                 show_usage(argc, argv);
 367                                 return -1;
 368                         }
 369                         wdelay = atol(argv[++i]);
 370                         break;
 371                 case 'v':
 372                         verbose_mode = 1;
 373                         break;
 374                 case 'h':
 375                         if (argc < i + 2) {
 376                                 show_usage(argc, argv);
 377                                 return -1;
 378                         }
 379                         init_hash_size = atol(argv[++i]);
 380                         break;
 381                 case 'm':
 382                         if (argc < i + 2) {
 383                                 show_usage(argc, argv);
 384                                 return -1;
 385                         }
 386                         min_hash_alloc_size = atol(argv[++i]);
 387                         break;
 388                 case 'n':
 389                         if (argc < i + 2) {
 390                                 show_usage(argc, argv);
 391                                 return -1;
 392                         }
 393                         max_hash_buckets_size = atol(argv[++i]);
 394                         break;
 395                 case 'u':
 396                         if (add_replace) {
 397                                 printf("Please specify at most one of -s or -u.\n");
 398                                 exit(-1);
 399                         }
 400                         add_unique = 1;
 401                         break;
 402                 case 's':
 403                         if (add_unique) {
 404                                 printf("Please specify at most one of -s or -u.\n");
 405                                 exit(-1);
 406                         }
 407                         add_replace = 1;
 408                         break;
 409                 case 'i':
 410                         add_only = 1;
 411                         break;
 412                 case 'k':
 413                         init_populate = atol(argv[++i]);
 414                         break;
 415                 case 'A':
 416                         opt_auto_resize = 1;
 417                         break;
 418                 case 'B':
 419                         if (argc < i + 2) {
 420                                 show_usage(argc, argv);
 421                                 return -1;
 422                         }
 423                         i++;
 424                         if (!strcmp("order", argv[i]))
 425                                 memory_backend = &cds_lfht_mm_order;
 426                         else if (!strcmp("chunk", argv[i]))
 427                                 memory_backend = &cds_lfht_mm_chunk;
 428                         else if (!strcmp("mmap", argv[i]))
 429                                 memory_backend = &cds_lfht_mm_mmap;
 430                         else {
 431                                 printf("Please specify memory backend with order|chunk|mmap.\n");
 432                                 exit(-1);
 433                         }
 434                         break;
 435                 case 'R':
 436                         lookup_pool_offset = atol(argv[++i]);
 437                         break;
 438                 case 'S':
 439                         write_pool_offset = atol(argv[++i]);
 440                         break;
 441                 case 'T':
 442                         init_pool_offset = atol(argv[++i]);
 443                         break;
 444                 case 'M':
 445                         lookup_pool_size = atol(argv[++i]);
 446                         break;
 447                 case 'N':
 448                         write_pool_size = atol(argv[++i]);
 449                         break;
 450                 case 'O':
 451                         init_pool_size = atol(argv[++i]);
 452                         break;
 453                 case 'V':
 454                         validate_lookup = 1;
 455                         break;
 456                 case 'U':
 457                         test_choice = TEST_HASH_UNIQUE;
 458                         break;
 459                 }
 460         }
 461
 462         /* Check if hash size is power of 2 */
 463         if (init_hash_size && init_hash_size & (init_hash_size - 1)) {
 464                 printf("Error: Initial number of buckets (%lu) is not a power of 2.\n",
 465                         init_hash_size);
 466                 return -1;
 467         }
 468
 469         if (min_hash_alloc_size && min_hash_alloc_size & (min_hash_alloc_size - 1)) {
 470                 printf("Error: Minimum number of allocated buckets (%lu) is not a power of 2.\n",
 471                         min_hash_alloc_size);
 472                 return -1;
 473         }
 474
 475         if (max_hash_buckets_size && max_hash_buckets_size & (max_hash_buckets_size - 1)) {
 476                 printf("Error: Maximum number of buckets (%lu) is not a power of 2.\n",
 477                         max_hash_buckets_size);
 478                 return -1;
 479         }
 480
 481         memset(&act, 0, sizeof(act));
 482         ret = sigemptyset(&act.sa_mask);
 483         if (ret == -1) {
 484                 perror("sigemptyset");
 485                 return -1;
 486         }
 487         act.sa_handler = get_sigusr1_cb();
 488         act.sa_flags = SA_RESTART;
 489         ret = sigaction(SIGUSR1, &act, NULL);
 490         if (ret == -1) {
 491                 perror("sigaction");
 492                 return -1;
 493         }
 494
 495         ret = pipe(count_pipe);
 496         if (ret == -1) {
 497                 perror("pipe");
 498                 return -1;
 499         }
 500
 501         /* spawn counter thread */
 502         err = pthread_create(&tid_count, NULL, thr_count,
 503                              NULL);
 504         if (err != 0)
 505                 exit(1);
 506
 507         act.sa_handler = get_sigusr2_cb();
 508         act.sa_flags = SA_RESTART;
 509         ret = sigaction(SIGUSR2, &act, NULL);
 510         if (ret == -1) {
 511                 perror("sigaction");
 512                 return -1;
 513         }
 514
 515         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 516                 duration, nr_readers, nr_writers);
 517         printf_verbose("Writer delay : %lu loops.\n", wdelay);
 518         printf_verbose("Reader duration : %lu loops.\n", rduration);
 519         printf_verbose("Mode:%s%s.\n",
 520                 add_only ? " add only" : " add/remove",
 521                 add_unique ? " uniquify" : ( add_replace ? " replace" : " insert"));
 522         printf_verbose("Initial number of buckets: %lu buckets.\n", init_hash_size);
 523         printf_verbose("Minimum number of allocated buckets: %lu buckets.\n", min_hash_alloc_size);
 524         printf_verbose("Maximum number of buckets: %lu buckets.\n", max_hash_buckets_size);
 525         printf_verbose("Init pool size offset %lu size %lu.\n",
 526                 init_pool_offset, init_pool_size);
 527         printf_verbose("Lookup pool size offset %lu size %lu.\n",
 528                 lookup_pool_offset, lookup_pool_size);
 529         printf_verbose("Update pool size offset %lu size %lu.\n",
 530                 write_pool_offset, write_pool_size);
 531         printf_verbose("thread %-6s, thread id : %lx, tid %lu\n",
 532                         "main", pthread_self(), (unsigned long)gettid());
 533
 534         tid_reader = malloc(sizeof(*tid_reader) * nr_readers);
 535         tid_writer = malloc(sizeof(*tid_writer) * nr_writers);
 536         count_reader = malloc(sizeof(*count_reader) * nr_readers);
 537         count_writer = malloc(sizeof(*count_writer) * nr_writers);
 538
 539         err = create_all_cpu_call_rcu_data(0);
 540         if (err) {
 541                 printf("Per-CPU call_rcu() worker threads unavailable. Using default global worker thread.\n");
 542         }
 543
 544         if (memory_backend) {
 545                 test_ht = _cds_lfht_new(init_hash_size, min_hash_alloc_size,
 546                                 max_hash_buckets_size,
 547                                 (opt_auto_resize ? CDS_LFHT_AUTO_RESIZE : 0) |
 548                                 CDS_LFHT_ACCOUNTING, memory_backend,
 549                                 &rcu_flavor, NULL);
 550         } else {
 551                 test_ht = cds_lfht_new(init_hash_size, min_hash_alloc_size,
 552                                 max_hash_buckets_size,
 553                                 (opt_auto_resize ? CDS_LFHT_AUTO_RESIZE : 0) |
 554                                 CDS_LFHT_ACCOUNTING, NULL);
 555         }
 556
 557         /*
 558          * Hash Population needs to be seen as a RCU reader
 559          * thread from the point of view of resize.
 560          */
 561         rcu_register_thread();
 562         ret = (get_populate_hash_cb())();
 563         assert(!ret);
 564
 565         rcu_thread_offline();
 566
 567         next_aff = 0;
 568
 569         for (i = 0; i < nr_readers; i++) {
 570                 err = pthread_create(&tid_reader[i],
 571                                      NULL, get_thr_reader_cb(),
 572                                      &count_reader[i]);
 573                 if (err != 0)
 574                         exit(1);
 575         }
 576         for (i = 0; i < nr_writers; i++) {
 577                 err = pthread_create(&tid_writer[i],
 578                                      NULL, get_thr_writer_cb(),
 579                                      &count_writer[i]);
 580                 if (err != 0)
 581                         exit(1);
 582         }
 583
 584         cmm_smp_mb();
 585
 586         test_go = 1;
 587
 588         remain = duration;
 589         do {
 590                 remain = sleep(remain);
 591         } while (remain > 0);
 592
 593         test_stop = 1;
 594
 595         for (i = 0; i < nr_readers; i++) {
 596                 err = pthread_join(tid_reader[i], &tret);
 597                 if (err != 0)
 598                         exit(1);
 599                 tot_reads += count_reader[i];
 600         }
 601         for (i = 0; i < nr_writers; i++) {
 602                 err = pthread_join(tid_writer[i], &tret);
 603                 if (err != 0)
 604                         exit(1);
 605                 tot_writes += count_writer[i].update_ops;
 606                 tot_add += count_writer[i].add;
 607                 tot_add_exist += count_writer[i].add_exist;
 608                 tot_remove += count_writer[i].remove;
 609         }
 610
 611         /* teardown counter thread */
 612         act.sa_handler = SIG_IGN;
 613         act.sa_flags = SA_RESTART;
 614         ret = sigaction(SIGUSR2, &act, NULL);
 615         if (ret == -1) {
 616                 perror("sigaction");
 617                 return -1;
 618         }
 619         {
 620                 char msg[1] = { 0x42 };
 621                 ssize_t ret;
 622
 623                 do {
 624                         ret = write(count_pipe[1], msg, 1);     /* wakeup thread */
 625                 } while (ret == -1L && errno == EINTR);
 626         }
 627         err = pthread_join(tid_count, &tret);
 628         if (err != 0)
 629                 exit(1);
 630
 631         fflush(stdout);
 632         rcu_thread_online();
 633         rcu_read_lock();
 634         printf("Counting nodes... ");
 635         cds_lfht_count_nodes(test_ht, &approx_before, &count, &approx_after);
 636         printf("done.\n");
 637         test_delete_all_nodes(test_ht);
 638         rcu_read_unlock();
 639         rcu_thread_offline();
 640         if (count) {
 641                 printf("Approximation before node accounting: %ld nodes.\n",
 642                         approx_before);
 643                 printf("Nodes deleted from hash table before destroy: "
 644                         "%lu nodes.\n",
 645                         count);
 646                 printf("Approximation after node accounting: %ld nodes.\n",
 647                         approx_after);
 648         }
 649         ret = cds_lfht_destroy(test_ht, NULL);
 650         if (ret)
 651                 printf_verbose("final delete aborted\n");
 652         else
 653                 printf_verbose("final delete success\n");
 654         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 655                tot_writes);
 656         printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu "
 657                 "nr_writers %3u "
 658                 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu "
 659                 "nr_add %12llu nr_add_fail %12llu nr_remove %12llu nr_leaked %12lld\n",
 660                 argv[0], duration, nr_readers, rduration,
 661                 nr_writers, wdelay, tot_reads, tot_writes,
 662                 tot_reads + tot_writes, tot_add, tot_add_exist, tot_remove,
 663                 (long long) tot_add + init_populate - tot_remove - count);
 664         rcu_unregister_thread();
 665         free_all_cpu_call_rcu_data();
 666         free(tid_reader);
 667         free(tid_writer);
 668         free(count_reader);
 669         free(count_writer);
 670         return 0;
 671 }