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 <sched.h>
  38 #include <errno.h>
  39
  40 #include <urcu/arch.h>
  41
  42 #ifdef __linux__
  43 #include <syscall.h>
  44 #endif
  45
  46 /* hardcoded number of CPUs */
  47 #define NR_CPUS 16384
  48
  49 #if defined(_syscall0)
  50 _syscall0(pid_t, gettid)
  51 #elif defined(__NR_gettid)
  52 static inline pid_t gettid(void)
  53 {
  54         return syscall(__NR_gettid);
  55 }
  56 #else
  57 #warning "use pid as tid"
  58 static inline pid_t gettid(void)
  59 {
  60         return getpid();
  61 }
  62 #endif
  63
  64 #ifndef DYNAMIC_LINK_TEST
  65 #define _LGPL_SOURCE
  66 #endif
  67 #include <urcu.h>
  68 #include <urcu/cds.h>
  69 #include <urcu-defer.h>
  70
  71 static volatile int test_go, test_stop;
  72
  73 static unsigned long rduration;
  74
  75 static unsigned long duration;
  76
  77 /* read-side C.S. duration, in loops */
  78 static unsigned long wdelay;
  79
  80 static inline void loop_sleep(unsigned long l)
  81 {
  82         while(l-- != 0)
  83                 caa_cpu_relax();
  84 }
  85
  86 static int verbose_mode;
  87
  88 #define printf_verbose(fmt, args...)            \
  89         do {                                    \
  90                 if (verbose_mode)               \
  91                         printf(fmt, args);      \
  92         } while (0)
  93
  94 static unsigned int cpu_affinities[NR_CPUS];
  95 static unsigned int next_aff = 0;
  96 static int use_affinity = 0;
  97
  98 pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
  99
 100 #ifndef HAVE_CPU_SET_T
 101 typedef unsigned long cpu_set_t;
 102 # define CPU_ZERO(cpuset) do { *(cpuset) = 0; } while(0)
 103 # define CPU_SET(cpu, cpuset) do { *(cpuset) |= (1UL << (cpu)); } while(0)
 104 #endif
 105
 106 static void set_affinity(void)
 107 {
 108         cpu_set_t mask;
 109         int cpu;
 110         int ret;
 111
 112         if (!use_affinity)
 113                 return;
 114
 115 #if HAVE_SCHED_SETAFFINITY
 116         ret = pthread_mutex_lock(&affinity_mutex);
 117         if (ret) {
 118                 perror("Error in pthread mutex lock");
 119                 exit(-1);
 120         }
 121         cpu = cpu_affinities[next_aff++];
 122         ret = pthread_mutex_unlock(&affinity_mutex);
 123         if (ret) {
 124                 perror("Error in pthread mutex unlock");
 125                 exit(-1);
 126         }
 127
 128         CPU_ZERO(&mask);
 129         CPU_SET(cpu, &mask);
 130 #if SCHED_SETAFFINITY_ARGS == 2
 131         sched_setaffinity(0, &mask);
 132 #else
 133         sched_setaffinity(0, sizeof(mask), &mask);
 134 #endif
 135 #endif /* HAVE_SCHED_SETAFFINITY */
 136 }
 137
 138 /*
 139  * returns 0 if test should end.
 140  */
 141 static int test_duration_dequeue(void)
 142 {
 143         return !test_stop;
 144 }
 145
 146 static int test_duration_enqueue(void)
 147 {
 148         return !test_stop;
 149 }
 150
 151 static unsigned long long __thread nr_dequeues;
 152 static unsigned long long __thread nr_enqueues;
 153
 154 static unsigned long long __thread nr_successful_dequeues;
 155 static unsigned long long __thread nr_successful_enqueues;
 156
 157 static unsigned int nr_enqueuers;
 158 static unsigned int nr_dequeuers;
 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", pthread_self(), (unsigned long)gettid());
 168
 169         set_affinity();
 170
 171         rcu_register_thread();
 172
 173         while (!test_go)
 174         {
 175         }
 176         cmm_smp_mb();
 177
 178         for (;;) {
 179                 struct cds_lfq_node_rcu *node = malloc(sizeof(*node));
 180                 if (!node)
 181                         goto fail;
 182                 cds_lfq_node_init_rcu(node);
 183                 cds_lfq_enqueue_rcu(&q, node);
 184                 nr_successful_enqueues++;
 185
 186                 if (unlikely(wdelay))
 187                         loop_sleep(wdelay);
 188 fail:
 189                 nr_enqueues++;
 190                 if (unlikely(!test_duration_enqueue()))
 191                         break;
 192         }
 193
 194         rcu_unregister_thread();
 195
 196         count[0] = nr_enqueues;
 197         count[1] = nr_successful_enqueues;
 198         printf_verbose("enqueuer thread_end, thread id : %lx, tid %lu, "
 199                        "enqueues %llu successful_enqueues %llu\n",
 200                        pthread_self(), (unsigned long)gettid(), nr_enqueues,
 201                        nr_successful_enqueues);
 202         return ((void*)1);
 203
 204 }
 205
 206 void *thr_dequeuer(void *_count)
 207 {
 208         unsigned long long *count = _count;
 209         int ret;
 210
 211         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 212                         "dequeuer", pthread_self(), (unsigned long)gettid());
 213
 214         set_affinity();
 215
 216         ret = rcu_defer_register_thread();
 217         if (ret) {
 218                 printf("Error in rcu_defer_register_thread\n");
 219                 exit(-1);
 220         }
 221         rcu_register_thread();
 222
 223         while (!test_go)
 224         {
 225         }
 226         cmm_smp_mb();
 227
 228         for (;;) {
 229                 struct cds_lfq_node_rcu *node;
 230
 231                 node = cds_lfq_dequeue_rcu(&q);
 232                 if (node) {
 233                         defer_rcu(free, node);
 234                         nr_successful_dequeues++;
 235                 }
 236
 237                 nr_dequeues++;
 238                 if (unlikely(!test_duration_dequeue()))
 239                         break;
 240                 if (unlikely(rduration))
 241                         loop_sleep(rduration);
 242         }
 243
 244         rcu_unregister_thread();
 245         rcu_defer_unregister_thread();
 246         printf_verbose("dequeuer thread_end, thread id : %lx, tid %lu, "
 247                        "dequeues %llu, successful_dequeues %llu\n",
 248                        pthread_self(), (unsigned long)gettid(), nr_dequeues,
 249                        nr_successful_dequeues);
 250         count[0] = nr_dequeues;
 251         count[1] = nr_successful_dequeues;
 252         return ((void*)2);
 253 }
 254
 255 void test_end(struct cds_lfq_queue_rcu *q, unsigned long long *nr_dequeues)
 256 {
 257         struct cds_lfq_node_rcu *node;
 258
 259         do {
 260                 node = cds_lfq_dequeue_rcu(q);
 261                 if (node) {
 262                         free(node);     /* no more concurrent access */
 263                         (*nr_dequeues)++;
 264                 }
 265         } while (node);
 266 }
 267
 268 void show_usage(int argc, char **argv)
 269 {
 270         printf("Usage : %s nr_dequeuers nr_enqueuers duration (s)", argv[0]);
 271         printf(" [-d delay] (enqueuer period (in loops))");
 272         printf(" [-c duration] (dequeuer period (in loops))");
 273         printf(" [-v] (verbose output)");
 274         printf(" [-a cpu#] [-a cpu#]... (affinity)");
 275         printf("\n");
 276 }
 277
 278 int main(int argc, char **argv)
 279 {
 280         int err;
 281         pthread_t *tid_enqueuer, *tid_dequeuer;
 282         void *tret;
 283         unsigned long long *count_enqueuer, *count_dequeuer;
 284         unsigned long long tot_enqueues = 0, tot_dequeues = 0;
 285         unsigned long long tot_successful_enqueues = 0,
 286                            tot_successful_dequeues = 0;
 287         unsigned long long end_dequeues = 0;
 288         int i, a;
 289
 290         if (argc < 4) {
 291                 show_usage(argc, argv);
 292                 return -1;
 293         }
 294
 295         err = sscanf(argv[1], "%u", &nr_dequeuers);
 296         if (err != 1) {
 297                 show_usage(argc, argv);
 298                 return -1;
 299         }
 300
 301         err = sscanf(argv[2], "%u", &nr_enqueuers);
 302         if (err != 1) {
 303                 show_usage(argc, argv);
 304                 return -1;
 305         }
 306
 307         err = sscanf(argv[3], "%lu", &duration);
 308         if (err != 1) {
 309                 show_usage(argc, argv);
 310                 return -1;
 311         }
 312
 313         for (i = 4; i < argc; i++) {
 314                 if (argv[i][0] != '-')
 315                         continue;
 316                 switch (argv[i][1]) {
 317                 case 'a':
 318                         if (argc < i + 2) {
 319                                 show_usage(argc, argv);
 320                                 return -1;
 321                         }
 322                         a = atoi(argv[++i]);
 323                         cpu_affinities[next_aff++] = a;
 324                         use_affinity = 1;
 325                         printf_verbose("Adding CPU %d affinity\n", a);
 326                         break;
 327                 case 'c':
 328                         if (argc < i + 2) {
 329                                 show_usage(argc, argv);
 330                                 return -1;
 331                         }
 332                         rduration = atol(argv[++i]);
 333                         break;
 334                 case 'd':
 335                         if (argc < i + 2) {
 336                                 show_usage(argc, argv);
 337                                 return -1;
 338                         }
 339                         wdelay = atol(argv[++i]);
 340                         break;
 341                 case 'v':
 342                         verbose_mode = 1;
 343                         break;
 344                 }
 345         }
 346
 347         printf_verbose("running test for %lu seconds, %u enqueuers, "
 348                        "%u dequeuers.\n",
 349                        duration, nr_enqueuers, nr_dequeuers);
 350         printf_verbose("Writer delay : %lu loops.\n", rduration);
 351         printf_verbose("Reader duration : %lu loops.\n", wdelay);
 352         printf_verbose("thread %-6s, thread id : %lx, tid %lu\n",
 353                         "main", pthread_self(), (unsigned long)gettid());
 354
 355         tid_enqueuer = malloc(sizeof(*tid_enqueuer) * nr_enqueuers);
 356         tid_dequeuer = malloc(sizeof(*tid_dequeuer) * nr_dequeuers);
 357         count_enqueuer = malloc(2 * sizeof(*count_enqueuer) * nr_enqueuers);
 358         count_dequeuer = malloc(2 * sizeof(*count_dequeuer) * nr_dequeuers);
 359         cds_lfq_init_rcu(&q);
 360
 361         next_aff = 0;
 362
 363         for (i = 0; i < nr_enqueuers; i++) {
 364                 err = pthread_create(&tid_enqueuer[i], NULL, thr_enqueuer,
 365                                      &count_enqueuer[2 * i]);
 366                 if (err != 0)
 367                         exit(1);
 368         }
 369         for (i = 0; i < nr_dequeuers; i++) {
 370                 err = pthread_create(&tid_dequeuer[i], NULL, thr_dequeuer,
 371                                      &count_dequeuer[2 * i]);
 372                 if (err != 0)
 373                         exit(1);
 374         }
 375
 376         cmm_smp_mb();
 377
 378         test_go = 1;
 379
 380         for (i = 0; i < duration; i++) {
 381                 sleep(1);
 382                 if (verbose_mode)
 383                         write (1, ".", 1);
 384         }
 385
 386         test_stop = 1;
 387
 388         for (i = 0; i < nr_enqueuers; i++) {
 389                 err = pthread_join(tid_enqueuer[i], &tret);
 390                 if (err != 0)
 391                         exit(1);
 392                 tot_enqueues += count_enqueuer[2 * i];
 393                 tot_successful_enqueues += count_enqueuer[2 * i + 1];
 394         }
 395         for (i = 0; i < nr_dequeuers; i++) {
 396                 err = pthread_join(tid_dequeuer[i], &tret);
 397                 if (err != 0)
 398                         exit(1);
 399                 tot_dequeues += count_dequeuer[2 * i];
 400                 tot_successful_dequeues += count_dequeuer[2 * i + 1];
 401         }
 402
 403         test_end(&q, &end_dequeues);
 404         err = cds_lfq_destroy_rcu(&q);
 405         assert(!err);
 406
 407         printf_verbose("total number of enqueues : %llu, dequeues %llu\n",
 408                        tot_enqueues, tot_dequeues);
 409         printf_verbose("total number of successful enqueues : %llu, "
 410                        "successful dequeues %llu\n",
 411                        tot_successful_enqueues, tot_successful_dequeues);
 412         printf("SUMMARY %-25s testdur %4lu nr_enqueuers %3u wdelay %6lu "
 413                 "nr_dequeuers %3u "
 414                 "rdur %6lu nr_enqueues %12llu nr_dequeues %12llu "
 415                 "successful enqueues %12llu successful dequeues %12llu "
 416                 "end_dequeues %llu nr_ops %12llu\n",
 417                 argv[0], duration, nr_enqueuers, wdelay,
 418                 nr_dequeuers, rduration, tot_enqueues, tot_dequeues,
 419                 tot_successful_enqueues,
 420                 tot_successful_dequeues, end_dequeues,
 421                 tot_enqueues + tot_dequeues);
 422         if (tot_successful_enqueues != tot_successful_dequeues + end_dequeues)
 423                 printf("WARNING! Discrepancy between nr succ. enqueues %llu vs "
 424                        "succ. dequeues + end dequeues %llu.\n",
 425                        tot_successful_enqueues,
 426                        tot_successful_dequeues + end_dequeues);
 427
 428         free(count_enqueuer);
 429         free(count_dequeuer);
 430         free(tid_enqueuer);
 431         free(tid_dequeuer);
 432         return 0;
 433 }