tests/test_urcu_lfq.c

   1 /*
   2  * test_urcu_lfq.c
   3  *
   4  * Userspace RCU library - example RCU-based lock-free queue
   5  *
   6  * Copyright February 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  * Copyright February 2010 - Paolo Bonzini <pbonzini@redhat.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  22  */
  23
  24 #define _GNU_SOURCE
  25 #include "../config.h"
  26 #include <stdio.h>
  27 #include <pthread.h>
  28 #include <stdlib.h>
  29 #include <stdint.h>
  30 #include <stdbool.h>
  31 #include <string.h>
  32 #include <sys/types.h>
  33 #include <sys/wait.h>
  34 #include <unistd.h>
  35 #include <stdio.h>
  36 #include <assert.h>
  37 #include <errno.h>
  38
  39 #include <urcu/arch.h>
  40 #include <urcu/tls-compat.h>
  41 #include "cpuset.h"
  42
  43 #ifdef __linux__
  44 #include <syscall.h>
  45 #endif
  46
  47 /* hardcoded number of CPUs */
  48 #define NR_CPUS 16384
  49
  50 #if defined(_syscall0)
  51 _syscall0(pid_t, gettid)
  52 #elif defined(__NR_gettid)
  53 static inline pid_t gettid(void)
  54 {
  55         return syscall(__NR_gettid);
  56 }
  57 #else
  58 #warning "use pid as tid"
  59 static inline pid_t gettid(void)
  60 {
  61         return getpid();
  62 }
  63 #endif
  64
  65 #ifndef DYNAMIC_LINK_TEST
  66 #define _LGPL_SOURCE
  67 #endif
  68 #include <urcu.h>
  69 #include <urcu/cds.h>
  70 #include <urcu-defer.h>
  71
  72 static volatile int test_go, test_stop;
  73
  74 static unsigned long rduration;
  75
  76 static unsigned long duration;
  77
  78 /* read-side C.S. duration, in loops */
  79 static unsigned long wdelay;
  80
  81 static inline void loop_sleep(unsigned long l)
  82 {
  83         while(l-- != 0)
  84                 caa_cpu_relax();
  85 }
  86
  87 static int verbose_mode;
  88
  89 #define printf_verbose(fmt, args...)            \
  90         do {                                    \
  91                 if (verbose_mode)               \
  92                         printf(fmt, args);      \
  93         } while (0)
  94
  95 static unsigned int cpu_affinities[NR_CPUS];
  96 static unsigned int next_aff = 0;
  97 static int use_affinity = 0;
  98
  99 pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
 100
 101 static void set_affinity(void)
 102 {
 103         cpu_set_t mask;
 104         int cpu;
 105         int ret;
 106
 107         if (!use_affinity)
 108                 return;
 109
 110 #if HAVE_SCHED_SETAFFINITY
 111         ret = pthread_mutex_lock(&affinity_mutex);
 112         if (ret) {
 113                 perror("Error in pthread mutex lock");
 114                 exit(-1);
 115         }
 116         cpu = cpu_affinities[next_aff++];
 117         ret = pthread_mutex_unlock(&affinity_mutex);
 118         if (ret) {
 119                 perror("Error in pthread mutex unlock");
 120                 exit(-1);
 121         }
 122
 123         CPU_ZERO(&mask);
 124         CPU_SET(cpu, &mask);
 125 #if SCHED_SETAFFINITY_ARGS == 2
 126         sched_setaffinity(0, &mask);
 127 #else
 128         sched_setaffinity(0, sizeof(mask), &mask);
 129 #endif
 130 #endif /* HAVE_SCHED_SETAFFINITY */
 131 }
 132
 133 /*
 134  * returns 0 if test should end.
 135  */
 136 static int test_duration_dequeue(void)
 137 {
 138         return !test_stop;
 139 }
 140
 141 static int test_duration_enqueue(void)
 142 {
 143         return !test_stop;
 144 }
 145
 146 static DEFINE_URCU_TLS(unsigned long long, nr_dequeues);
 147 static DEFINE_URCU_TLS(unsigned long long, nr_enqueues);
 148
 149 static DEFINE_URCU_TLS(unsigned long long, nr_successful_dequeues);
 150 static DEFINE_URCU_TLS(unsigned long long, nr_successful_enqueues);
 151
 152 static unsigned int nr_enqueuers;
 153 static unsigned int nr_dequeuers;
 154
 155 struct test {
 156         struct cds_lfq_node_rcu list;
 157         struct rcu_head rcu;
 158 };
 159
 160 static struct cds_lfq_queue_rcu q;
 161
 162 void *thr_enqueuer(void *_count)
 163 {
 164         unsigned long long *count = _count;
 165
 166         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 167                         "enqueuer", (unsigned long) pthread_self(),
 168                         (unsigned long) gettid());
 169
 170         set_affinity();
 171
 172         rcu_register_thread();
 173
 174         while (!test_go)
 175         {
 176         }
 177         cmm_smp_mb();
 178
 179         for (;;) {
 180                 struct test *node = malloc(sizeof(*node));
 181                 if (!node)
 182                         goto fail;
 183                 cds_lfq_node_init_rcu(&node->list);
 184                 rcu_read_lock();
 185                 cds_lfq_enqueue_rcu(&q, &node->list);
 186                 rcu_read_unlock();
 187                 URCU_TLS(nr_successful_enqueues)++;
 188
 189                 if (caa_unlikely(wdelay))
 190                         loop_sleep(wdelay);
 191 fail:
 192                 URCU_TLS(nr_enqueues)++;
 193                 if (caa_unlikely(!test_duration_enqueue()))
 194                         break;
 195         }
 196
 197         rcu_unregister_thread();
 198
 199         count[0] = URCU_TLS(nr_enqueues);
 200         count[1] = URCU_TLS(nr_successful_enqueues);
 201         printf_verbose("enqueuer thread_end, thread id : %lx, tid %lu, "
 202                        "enqueues %llu successful_enqueues %llu\n",
 203                        (unsigned long) pthread_self(),
 204                         (unsigned long) gettid(),
 205                        URCU_TLS(nr_enqueues), URCU_TLS(nr_successful_enqueues));
 206         return ((void*)1);
 207
 208 }
 209
 210 static
 211 void free_node_cb(struct rcu_head *head)
 212 {
 213         struct test *node =
 214                 caa_container_of(head, struct test, rcu);
 215         free(node);
 216 }
 217
 218 void *thr_dequeuer(void *_count)
 219 {
 220         unsigned long long *count = _count;
 221         int ret;
 222
 223         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 224                         "dequeuer", (unsigned long) pthread_self(),
 225                         (unsigned long) gettid());
 226
 227         set_affinity();
 228
 229         ret = rcu_defer_register_thread();
 230         if (ret) {
 231                 printf("Error in rcu_defer_register_thread\n");
 232                 exit(-1);
 233         }
 234         rcu_register_thread();
 235
 236         while (!test_go)
 237         {
 238         }
 239         cmm_smp_mb();
 240
 241         for (;;) {
 242                 struct cds_lfq_node_rcu *qnode;
 243                 struct test *node;
 244
 245                 rcu_read_lock();
 246                 qnode = cds_lfq_dequeue_rcu(&q);
 247                 node = caa_container_of(qnode, struct test, list);
 248                 rcu_read_unlock();
 249
 250                 if (node) {
 251                         call_rcu(&node->rcu, free_node_cb);
 252                         URCU_TLS(nr_successful_dequeues)++;
 253                 }
 254
 255                 URCU_TLS(nr_dequeues)++;
 256                 if (caa_unlikely(!test_duration_dequeue()))
 257                         break;
 258                 if (caa_unlikely(rduration))
 259                         loop_sleep(rduration);
 260         }
 261
 262         rcu_unregister_thread();
 263         rcu_defer_unregister_thread();
 264         printf_verbose("dequeuer thread_end, thread id : %lx, tid %lu, "
 265                        "dequeues %llu, successful_dequeues %llu\n",
 266                        (unsigned long) pthread_self(),
 267                         (unsigned long) gettid(),
 268                        URCU_TLS(nr_dequeues), URCU_TLS(nr_successful_dequeues));
 269         count[0] = URCU_TLS(nr_dequeues);
 270         count[1] = URCU_TLS(nr_successful_dequeues);
 271         return ((void*)2);
 272 }
 273
 274 void test_end(struct cds_lfq_queue_rcu *q, unsigned long long *nr_dequeues)
 275 {
 276         struct cds_lfq_node_rcu *snode;
 277
 278         do {
 279                 snode = cds_lfq_dequeue_rcu(q);
 280                 if (snode) {
 281                         struct test *node;
 282
 283                         node = caa_container_of(snode, struct test, list);
 284                         free(node);     /* no more concurrent access */
 285                         (*nr_dequeues)++;
 286                 }
 287         } while (snode);
 288 }
 289
 290 void show_usage(int argc, char **argv)
 291 {
 292         printf("Usage : %s nr_dequeuers nr_enqueuers duration (s)", argv[0]);
 293         printf(" [-d delay] (enqueuer period (in loops))");
 294         printf(" [-c duration] (dequeuer period (in loops))");
 295         printf(" [-v] (verbose output)");
 296         printf(" [-a cpu#] [-a cpu#]... (affinity)");
 297         printf("\n");
 298 }
 299
 300 int main(int argc, char **argv)
 301 {
 302         int err;
 303         pthread_t *tid_enqueuer, *tid_dequeuer;
 304         void *tret;
 305         unsigned long long *count_enqueuer, *count_dequeuer;
 306         unsigned long long tot_enqueues = 0, tot_dequeues = 0;
 307         unsigned long long tot_successful_enqueues = 0,
 308                            tot_successful_dequeues = 0;
 309         unsigned long long end_dequeues = 0;
 310         int i, a;
 311
 312         if (argc < 4) {
 313                 show_usage(argc, argv);
 314                 return -1;
 315         }
 316
 317         err = sscanf(argv[1], "%u", &nr_dequeuers);
 318         if (err != 1) {
 319                 show_usage(argc, argv);
 320                 return -1;
 321         }
 322
 323         err = sscanf(argv[2], "%u", &nr_enqueuers);
 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                 case 'a':
 340                         if (argc < i + 2) {
 341                                 show_usage(argc, argv);
 342                                 return -1;
 343                         }
 344                         a = atoi(argv[++i]);
 345                         cpu_affinities[next_aff++] = a;
 346                         use_affinity = 1;
 347                         printf_verbose("Adding CPU %d affinity\n", a);
 348                         break;
 349                 case 'c':
 350                         if (argc < i + 2) {
 351                                 show_usage(argc, argv);
 352                                 return -1;
 353                         }
 354                         rduration = atol(argv[++i]);
 355                         break;
 356                 case 'd':
 357                         if (argc < i + 2) {
 358                                 show_usage(argc, argv);
 359                                 return -1;
 360                         }
 361                         wdelay = 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 enqueuers, "
 370                        "%u dequeuers.\n",
 371                        duration, nr_enqueuers, nr_dequeuers);
 372         printf_verbose("Writer delay : %lu loops.\n", rduration);
 373         printf_verbose("Reader duration : %lu loops.\n", wdelay);
 374         printf_verbose("thread %-6s, thread id : %lx, tid %lu\n",
 375                         "main", (unsigned long) pthread_self(),
 376                         (unsigned long) gettid());
 377
 378         tid_enqueuer = calloc(nr_enqueuers, sizeof(*tid_enqueuer));
 379         tid_dequeuer = calloc(nr_dequeuers, sizeof(*tid_dequeuer));
 380         count_enqueuer = calloc(nr_enqueuers, 2 * sizeof(*count_enqueuer));
 381         count_dequeuer = calloc(nr_dequeuers, 2 * sizeof(*count_dequeuer));
 382         cds_lfq_init_rcu(&q, call_rcu);
 383         err = create_all_cpu_call_rcu_data(0);
 384         if (err) {
 385                 printf("Per-CPU call_rcu() worker threads unavailable. Using default global worker thread.\n");
 386         }
 387
 388         next_aff = 0;
 389
 390         for (i = 0; i < nr_enqueuers; i++) {
 391                 err = pthread_create(&tid_enqueuer[i], NULL, thr_enqueuer,
 392                                      &count_enqueuer[2 * i]);
 393                 if (err != 0)
 394                         exit(1);
 395         }
 396         for (i = 0; i < nr_dequeuers; i++) {
 397                 err = pthread_create(&tid_dequeuer[i], NULL, thr_dequeuer,
 398                                      &count_dequeuer[2 * i]);
 399                 if (err != 0)
 400                         exit(1);
 401         }
 402
 403         cmm_smp_mb();
 404
 405         test_go = 1;
 406
 407         for (i = 0; i < duration; i++) {
 408                 sleep(1);
 409                 if (verbose_mode)
 410                         write (1, ".", 1);
 411         }
 412
 413         test_stop = 1;
 414
 415         for (i = 0; i < nr_enqueuers; i++) {
 416                 err = pthread_join(tid_enqueuer[i], &tret);
 417                 if (err != 0)
 418                         exit(1);
 419                 tot_enqueues += count_enqueuer[2 * i];
 420                 tot_successful_enqueues += count_enqueuer[2 * i + 1];
 421         }
 422         for (i = 0; i < nr_dequeuers; i++) {
 423                 err = pthread_join(tid_dequeuer[i], &tret);
 424                 if (err != 0)
 425                         exit(1);
 426                 tot_dequeues += count_dequeuer[2 * i];
 427                 tot_successful_dequeues += count_dequeuer[2 * i + 1];
 428         }
 429
 430         test_end(&q, &end_dequeues);
 431         err = cds_lfq_destroy_rcu(&q);
 432         assert(!err);
 433
 434         printf_verbose("total number of enqueues : %llu, dequeues %llu\n",
 435                        tot_enqueues, tot_dequeues);
 436         printf_verbose("total number of successful enqueues : %llu, "
 437                        "successful dequeues %llu\n",
 438                        tot_successful_enqueues, tot_successful_dequeues);
 439         printf("SUMMARY %-25s testdur %4lu nr_enqueuers %3u wdelay %6lu "
 440                 "nr_dequeuers %3u "
 441                 "rdur %6lu nr_enqueues %12llu nr_dequeues %12llu "
 442                 "successful enqueues %12llu successful dequeues %12llu "
 443                 "end_dequeues %llu nr_ops %12llu\n",
 444                 argv[0], duration, nr_enqueuers, wdelay,
 445                 nr_dequeuers, rduration, tot_enqueues, tot_dequeues,
 446                 tot_successful_enqueues,
 447                 tot_successful_dequeues, end_dequeues,
 448                 tot_enqueues + tot_dequeues);
 449         if (tot_successful_enqueues != tot_successful_dequeues + end_dequeues)
 450                 printf("WARNING! Discrepancy between nr succ. enqueues %llu vs "
 451                        "succ. dequeues + end dequeues %llu.\n",
 452                        tot_successful_enqueues,
 453                        tot_successful_dequeues + end_dequeues);
 454
 455         free_all_cpu_call_rcu_data();
 456         free(count_enqueuer);
 457         free(count_dequeuer);
 458         free(tid_enqueuer);
 459         free(tid_dequeuer);
 460         return 0;
 461 }