tests/benchmark/test_urcu_wfs.c

   1 // SPDX-FileCopyrightText: 2010 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   2 // SPDX-FileCopyrightText: 2010 Paolo Bonzini <pbonzini@redhat.com>
   3 //
   4 // SPDX-License-Identifier: GPL-2.0-or-later
   5
   6  /*
   7  * Userspace RCU library - example RCU-based lock-free stack
   8  */
   9
  10 #include <stdio.h>
  11 #include <pthread.h>
  12 #include <stdlib.h>
  13 #include <stdint.h>
  14 #include <stdbool.h>
  15 #include <string.h>
  16 #include <sys/types.h>
  17 #include <sys/wait.h>
  18 #include <unistd.h>
  19 #include <stdio.h>
  20 #include <errno.h>
  21
  22 #include <urcu/arch.h>
  23 #include <urcu/assert.h>
  24 #include <urcu/tls-compat.h>
  25 #include <urcu/uatomic.h>
  26 #include "thread-id.h"
  27
  28 /* hardcoded number of CPUs */
  29 #define NR_CPUS 16384
  30
  31 #ifndef DYNAMIC_LINK_TEST
  32 #define _LGPL_SOURCE
  33 #endif
  34 #include <urcu/wfstack.h>
  35
  36 /*
  37  * External synchronization used.
  38  */
  39 enum test_sync {
  40         TEST_SYNC_NONE = 0,
  41         TEST_SYNC_MUTEX,
  42 };
  43
  44 static enum test_sync test_sync;
  45
  46 static int test_force_sync;
  47
  48 static volatile int test_go, test_stop_enqueue, test_stop_dequeue;
  49
  50 static unsigned long rduration;
  51
  52 static unsigned long duration;
  53
  54 /* read-side C.S. duration, in loops */
  55 static unsigned long wdelay;
  56
  57 static inline void loop_sleep(unsigned long loops)
  58 {
  59         while (loops-- != 0)
  60                 caa_cpu_relax();
  61 }
  62
  63 static int verbose_mode;
  64
  65 static int test_pop, test_pop_all, test_wait_empty;
  66 static unsigned int test_enqueue_stopped;
  67
  68 #define printf_verbose(fmt, args...)            \
  69         do {                                    \
  70                 if (verbose_mode)               \
  71                         printf(fmt, ## args);   \
  72         } while (0)
  73
  74 static unsigned int cpu_affinities[NR_CPUS];
  75 static unsigned int next_aff = 0;
  76 static int use_affinity = 0;
  77
  78 pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
  79
  80 static void set_affinity(void)
  81 {
  82 #ifdef HAVE_SCHED_SETAFFINITY
  83         cpu_set_t mask;
  84         int cpu, ret;
  85 #endif /* HAVE_SCHED_SETAFFINITY */
  86
  87         if (!use_affinity)
  88                 return;
  89
  90 #ifdef HAVE_SCHED_SETAFFINITY
  91         ret = pthread_mutex_lock(&affinity_mutex);
  92         if (ret) {
  93                 perror("Error in pthread mutex lock");
  94                 exit(-1);
  95         }
  96         cpu = cpu_affinities[next_aff++];
  97         ret = pthread_mutex_unlock(&affinity_mutex);
  98         if (ret) {
  99                 perror("Error in pthread mutex unlock");
 100                 exit(-1);
 101         }
 102
 103         CPU_ZERO(&mask);
 104         CPU_SET(cpu, &mask);
 105         sched_setaffinity(0, sizeof(mask), &mask);
 106 #endif /* HAVE_SCHED_SETAFFINITY */
 107 }
 108
 109 /*
 110  * returns 0 if test should end.
 111  */
 112 static int test_duration_dequeue(void)
 113 {
 114         return !test_stop_dequeue;
 115 }
 116
 117 static int test_duration_enqueue(void)
 118 {
 119         return !test_stop_enqueue;
 120 }
 121
 122 static DEFINE_URCU_TLS(unsigned long long, nr_dequeues);
 123 static DEFINE_URCU_TLS(unsigned long long, nr_enqueues);
 124
 125 static DEFINE_URCU_TLS(unsigned long long, nr_successful_dequeues);
 126 static DEFINE_URCU_TLS(unsigned long long, nr_successful_enqueues);
 127 static DEFINE_URCU_TLS(unsigned long long, nr_empty_dest_enqueues);
 128 static DEFINE_URCU_TLS(unsigned long long, nr_pop_all);
 129 static DEFINE_URCU_TLS(unsigned long long, nr_pop_last);
 130
 131 static unsigned int nr_enqueuers;
 132 static unsigned int nr_dequeuers;
 133
 134 static struct cds_wfs_stack s;
 135
 136 static void *thr_enqueuer(void *_count)
 137 {
 138         unsigned long long *count = _count;
 139         bool was_nonempty;
 140
 141         printf_verbose("thread_begin %s, tid %lu\n",
 142                         "enqueuer", urcu_get_thread_id());
 143
 144         set_affinity();
 145
 146         while (!test_go)
 147         {
 148         }
 149         cmm_smp_mb();
 150
 151         for (;;) {
 152                 struct cds_wfs_node *node = malloc(sizeof(*node));
 153                 if (!node)
 154                         goto fail;
 155                 cds_wfs_node_init(node);
 156                 was_nonempty = cds_wfs_push(&s, node);
 157                 URCU_TLS(nr_successful_enqueues)++;
 158                 if (!was_nonempty)
 159                         URCU_TLS(nr_empty_dest_enqueues)++;
 160
 161                 if (caa_unlikely(wdelay))
 162                         loop_sleep(wdelay);
 163 fail:
 164                 URCU_TLS(nr_enqueues)++;
 165                 if (caa_unlikely(!test_duration_enqueue()))
 166                         break;
 167         }
 168
 169         uatomic_inc(&test_enqueue_stopped);
 170         count[0] = URCU_TLS(nr_enqueues);
 171         count[1] = URCU_TLS(nr_successful_enqueues);
 172         count[2] = URCU_TLS(nr_empty_dest_enqueues);
 173         printf_verbose("enqueuer thread_end, tid %lu, "
 174                         "enqueues %llu successful_enqueues %llu, "
 175                         "empty_dest_enqueues %llu\n",
 176                         urcu_get_thread_id(),
 177                         URCU_TLS(nr_enqueues),
 178                         URCU_TLS(nr_successful_enqueues),
 179                         URCU_TLS(nr_empty_dest_enqueues));
 180         return ((void*)1);
 181
 182 }
 183
 184 static void do_test_pop(enum test_sync sync)
 185 {
 186         struct cds_wfs_node *node;
 187         int state;
 188
 189         if (sync == TEST_SYNC_MUTEX)
 190                 cds_wfs_pop_lock(&s);
 191         node = __cds_wfs_pop_with_state_blocking(&s, &state);
 192         if (sync == TEST_SYNC_MUTEX)
 193                 cds_wfs_pop_unlock(&s);
 194
 195         if (node) {
 196                 if (state & CDS_WFS_STATE_LAST)
 197                         URCU_TLS(nr_pop_last)++;
 198                 free(node);
 199                 URCU_TLS(nr_successful_dequeues)++;
 200         }
 201         URCU_TLS(nr_dequeues)++;
 202 }
 203
 204 static void do_test_pop_all(enum test_sync sync)
 205 {
 206         struct cds_wfs_head *head;
 207         struct cds_wfs_node *node, *n;
 208
 209         if (sync == TEST_SYNC_MUTEX)
 210                 cds_wfs_pop_lock(&s);
 211         head = __cds_wfs_pop_all(&s);
 212         if (sync == TEST_SYNC_MUTEX)
 213                 cds_wfs_pop_unlock(&s);
 214
 215         /* Check if empty */
 216         if (cds_wfs_first(head) == NULL)
 217                 return;
 218
 219         URCU_TLS(nr_pop_all)++;
 220         URCU_TLS(nr_pop_last)++;
 221
 222         cds_wfs_for_each_blocking_safe(head, node, n) {
 223                 free(node);
 224                 URCU_TLS(nr_successful_dequeues)++;
 225                 URCU_TLS(nr_dequeues)++;
 226         }
 227 }
 228
 229 static void *thr_dequeuer(void *_count)
 230 {
 231         unsigned long long *count = _count;
 232         unsigned int counter = 0;
 233
 234         printf_verbose("thread_begin %s, tid %lu\n",
 235                         "dequeuer", urcu_get_thread_id());
 236
 237         set_affinity();
 238
 239         while (!test_go)
 240         {
 241         }
 242         cmm_smp_mb();
 243
 244         urcu_posix_assert(test_pop || test_pop_all);
 245
 246         for (;;) {
 247                 if (test_pop && test_pop_all) {
 248                         if (counter & 1)
 249                                 do_test_pop(test_sync);
 250                         else
 251                                 do_test_pop_all(test_sync);
 252                         counter++;
 253                 } else {
 254                         if (test_pop)
 255                                 do_test_pop(test_sync);
 256                         else
 257                                 do_test_pop_all(test_sync);
 258                 }
 259
 260                 if (caa_unlikely(!test_duration_dequeue()))
 261                         break;
 262                 if (caa_unlikely(rduration))
 263                         loop_sleep(rduration);
 264         }
 265
 266         printf_verbose("dequeuer thread_end, tid %lu, "
 267                         "dequeues %llu, successful_dequeues %llu "
 268                         "pop_all %llu pop_last %llu\n",
 269                         urcu_get_thread_id(),
 270                         URCU_TLS(nr_dequeues), URCU_TLS(nr_successful_dequeues),
 271                         URCU_TLS(nr_pop_all),
 272                         URCU_TLS(nr_pop_last));
 273         count[0] = URCU_TLS(nr_dequeues);
 274         count[1] = URCU_TLS(nr_successful_dequeues);
 275         count[2] = URCU_TLS(nr_pop_all);
 276         count[3] = URCU_TLS(nr_pop_last);
 277         return ((void*)2);
 278 }
 279
 280 static void test_end(unsigned long long *nr_dequeues_l,
 281                 unsigned long long *nr_pop_last_l)
 282 {
 283         struct cds_wfs_node *node;
 284         int state;
 285
 286         do {
 287                 node = cds_wfs_pop_with_state_blocking(&s, &state);
 288                 if (node) {
 289                         if (state & CDS_WFS_STATE_LAST)
 290                                 (*nr_pop_last_l)++;
 291                         free(node);
 292                         (*nr_dequeues_l)++;
 293                 }
 294         } while (node);
 295 }
 296
 297 static void show_usage(char **argv)
 298 {
 299         printf("Usage : %s nr_dequeuers nr_enqueuers duration (s) <OPTIONS>\n",
 300                 argv[0]);
 301         printf("OPTIONS:\n");
 302         printf("        [-d delay] (enqueuer period (in loops))\n");
 303         printf("        [-c duration] (dequeuer period (in loops))\n");
 304         printf("        [-v] (verbose output)\n");
 305         printf("        [-a cpu#] [-a cpu#]... (affinity)\n");
 306         printf("        [-p] (test pop)\n");
 307         printf("        [-P] (test pop_all, enabled by default)\n");
 308         printf("        [-M] (use mutex external synchronization)\n");
 309         printf("                Note: default: no external synchronization used.\n");
 310         printf("        [-f] (force user-provided synchronization)\n");
 311         printf("        [-w] Wait for dequeuer to empty stack\n");
 312         printf("\n");
 313 }
 314
 315 int main(int argc, char **argv)
 316 {
 317         int err;
 318         pthread_t *tid_enqueuer, *tid_dequeuer;
 319         void *tret;
 320         unsigned long long *count_enqueuer, *count_dequeuer;
 321         unsigned long long tot_enqueues = 0, tot_dequeues = 0;
 322         unsigned long long tot_successful_enqueues = 0,
 323                            tot_successful_dequeues = 0,
 324                            tot_empty_dest_enqueues = 0,
 325                            tot_pop_all = 0, tot_pop_last = 0;
 326         unsigned long long end_dequeues = 0;
 327         int i, a, retval = 0;
 328         unsigned int i_thr;
 329
 330         if (argc < 4) {
 331                 show_usage(argv);
 332                 return -1;
 333         }
 334
 335         err = sscanf(argv[1], "%u", &nr_dequeuers);
 336         if (err != 1) {
 337                 show_usage(argv);
 338                 return -1;
 339         }
 340
 341         err = sscanf(argv[2], "%u", &nr_enqueuers);
 342         if (err != 1) {
 343                 show_usage(argv);
 344                 return -1;
 345         }
 346
 347         err = sscanf(argv[3], "%lu", &duration);
 348         if (err != 1) {
 349                 show_usage(argv);
 350                 return -1;
 351         }
 352
 353         for (i = 4; i < argc; i++) {
 354                 if (argv[i][0] != '-')
 355                         continue;
 356                 switch (argv[i][1]) {
 357                 case 'a':
 358                         if (argc < i + 2) {
 359                                 show_usage(argv);
 360                                 return -1;
 361                         }
 362                         a = atoi(argv[++i]);
 363                         cpu_affinities[next_aff++] = a;
 364                         use_affinity = 1;
 365                         printf_verbose("Adding CPU %d affinity\n", a);
 366                         break;
 367                 case 'c':
 368                         if (argc < i + 2) {
 369                                 show_usage(argv);
 370                                 return -1;
 371                         }
 372                         rduration = atol(argv[++i]);
 373                         break;
 374                 case 'd':
 375                         if (argc < i + 2) {
 376                                 show_usage(argv);
 377                                 return -1;
 378                         }
 379                         wdelay = atol(argv[++i]);
 380                         break;
 381                 case 'v':
 382                         verbose_mode = 1;
 383                         break;
 384                 case 'p':
 385                         test_pop = 1;
 386                         break;
 387                 case 'P':
 388                         test_pop_all = 1;
 389                         break;
 390                 case 'M':
 391                         test_sync = TEST_SYNC_MUTEX;
 392                         break;
 393                 case 'w':
 394                         test_wait_empty = 1;
 395                         break;
 396                 case 'f':
 397                         test_force_sync = 1;
 398                         break;
 399                 }
 400         }
 401
 402         /* activate pop_all test by default */
 403         if (!test_pop && !test_pop_all)
 404                 test_pop_all = 1;
 405
 406         if (test_sync == TEST_SYNC_NONE && nr_dequeuers > 1 && test_pop) {
 407                 if (test_force_sync) {
 408                         fprintf(stderr, "[WARNING] Using pop concurrently "
 409                                 "with other pop or pop_all without external "
 410                                 "synchronization. Expect run-time failure.\n");
 411                 } else {
 412                         printf("Enforcing mutex synchronization\n");
 413                         test_sync = TEST_SYNC_MUTEX;
 414                 }
 415         }
 416
 417         printf_verbose("running test for %lu seconds, %u enqueuers, "
 418                        "%u dequeuers.\n",
 419                        duration, nr_enqueuers, nr_dequeuers);
 420         if (test_pop)
 421                 printf_verbose("pop test activated.\n");
 422         if (test_pop_all)
 423                 printf_verbose("pop_all test activated.\n");
 424         if (test_sync == TEST_SYNC_MUTEX)
 425                 printf_verbose("External sync: mutex.\n");
 426         else
 427                 printf_verbose("External sync: none.\n");
 428         if (test_wait_empty)
 429                 printf_verbose("Wait for dequeuers to empty stack.\n");
 430         printf_verbose("Writer delay : %lu loops.\n", rduration);
 431         printf_verbose("Reader duration : %lu loops.\n", wdelay);
 432         printf_verbose("thread %-6s, tid %lu\n",
 433                         "main", urcu_get_thread_id());
 434
 435         tid_enqueuer = calloc(nr_enqueuers, sizeof(*tid_enqueuer));
 436         tid_dequeuer = calloc(nr_dequeuers, sizeof(*tid_dequeuer));
 437         count_enqueuer = calloc(nr_enqueuers, 3 * sizeof(*count_enqueuer));
 438         count_dequeuer = calloc(nr_dequeuers, 4 * sizeof(*count_dequeuer));
 439         cds_wfs_init(&s);
 440
 441         next_aff = 0;
 442
 443         for (i_thr = 0; i_thr < nr_enqueuers; i_thr++) {
 444                 err = pthread_create(&tid_enqueuer[i], NULL, thr_enqueuer,
 445                                      &count_enqueuer[3 * i_thr]);
 446                 if (err != 0)
 447                         exit(1);
 448         }
 449         for (i_thr = 0; i_thr < nr_dequeuers; i_thr++) {
 450                 err = pthread_create(&tid_dequeuer[i_thr], NULL, thr_dequeuer,
 451                                      &count_dequeuer[4 * i_thr]);
 452                 if (err != 0)
 453                         exit(1);
 454         }
 455
 456         cmm_smp_mb();
 457
 458         test_go = 1;
 459
 460         for (i_thr = 0; i_thr < duration; i_thr++) {
 461                 sleep(1);
 462                 if (verbose_mode) {
 463                         fwrite(".", sizeof(char), 1, stdout);
 464                         fflush(stdout);
 465                 }
 466         }
 467
 468         test_stop_enqueue = 1;
 469
 470         if (test_wait_empty) {
 471                 while (nr_enqueuers != uatomic_read(&test_enqueue_stopped)) {
 472                         sleep(1);
 473                 }
 474                 while (!cds_wfs_empty(&s)) {
 475                         sleep(1);
 476                 }
 477         }
 478
 479         test_stop_dequeue = 1;
 480
 481         for (i_thr = 0; i_thr < nr_enqueuers; i_thr++) {
 482                 err = pthread_join(tid_enqueuer[i_thr], &tret);
 483                 if (err != 0)
 484                         exit(1);
 485                 tot_enqueues += count_enqueuer[3 * i_thr];
 486                 tot_successful_enqueues += count_enqueuer[3 * i_thr + 1];
 487                 tot_empty_dest_enqueues += count_enqueuer[3 * i_thr + 2];
 488         }
 489         for (i_thr = 0; i_thr < nr_dequeuers; i_thr++) {
 490                 err = pthread_join(tid_dequeuer[i_thr], &tret);
 491                 if (err != 0)
 492                         exit(1);
 493                 tot_dequeues += count_dequeuer[4 * i_thr];
 494                 tot_successful_dequeues += count_dequeuer[4 * i_thr + 1];
 495                 tot_pop_all += count_dequeuer[4 * i_thr + 2];
 496                 tot_pop_last += count_dequeuer[4 * i_thr + 3];
 497         }
 498
 499         test_end(&end_dequeues, &tot_pop_last);
 500
 501         printf_verbose("total number of enqueues : %llu, dequeues %llu\n",
 502                        tot_enqueues, tot_dequeues);
 503         printf_verbose("total number of successful enqueues : %llu, "
 504                        "enqueues to empty dest : %llu, "
 505                        "successful dequeues %llu, "
 506                        "pop_all : %llu, pop_last : %llu\n",
 507                        tot_successful_enqueues,
 508                        tot_empty_dest_enqueues,
 509                        tot_successful_dequeues,
 510                        tot_pop_all, tot_pop_last);
 511         printf("SUMMARY %-25s testdur %4lu nr_enqueuers %3u wdelay %6lu "
 512                 "nr_dequeuers %3u "
 513                 "rdur %6lu nr_enqueues %12llu nr_dequeues %12llu "
 514                 "successful enqueues %12llu enqueues to empty dest %12llu "
 515                 "successful dequeues %12llu pop_all %12llu "
 516                 "pop_last %llu end_dequeues %llu nr_ops %12llu\n",
 517                 argv[0], duration, nr_enqueuers, wdelay,
 518                 nr_dequeuers, rduration, tot_enqueues, tot_dequeues,
 519                 tot_successful_enqueues,
 520                 tot_empty_dest_enqueues,
 521                 tot_successful_dequeues, tot_pop_all, tot_pop_last,
 522                 end_dequeues,
 523                 tot_enqueues + tot_dequeues);
 524         if (tot_successful_enqueues != tot_successful_dequeues + end_dequeues) {
 525                 printf("WARNING! Discrepancy between nr succ. enqueues %llu vs "
 526                        "succ. dequeues + end dequeues %llu.\n",
 527                        tot_successful_enqueues,
 528                        tot_successful_dequeues + end_dequeues);
 529                 retval = 1;
 530         }
 531         /*
 532          * The enqueuer should see exactly as many empty queues than the
 533          * number of non-empty stacks dequeued.
 534          */
 535         if (tot_empty_dest_enqueues != tot_pop_last) {
 536                 printf("WARNING! Discrepancy between empty enqueue (%llu) and "
 537                         "number of pop last (%llu)\n",
 538                         tot_empty_dest_enqueues,
 539                         tot_pop_last);
 540                 retval = 1;
 541         }
 542
 543         cds_wfs_destroy(&s);
 544         free(count_enqueuer);
 545         free(count_dequeuer);
 546         free(tid_enqueuer);
 547         free(tid_dequeuer);
 548
 549         return retval;
 550 }