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 #include <urcu/tls-compat.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
  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 loops)
  81 {
  82         while (loops-- != 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 DEFINE_URCU_TLS(unsigned long long, nr_dequeues);
 152 static DEFINE_URCU_TLS(unsigned long long, nr_enqueues);
 153
 154 static DEFINE_URCU_TLS(unsigned long long, nr_successful_dequeues);
 155 static DEFINE_URCU_TLS(unsigned long long, nr_successful_enqueues);
 156
 157 static unsigned int nr_enqueuers;
 158 static unsigned int nr_dequeuers;
 159
 160 struct test {
 161         struct cds_lfq_node_rcu list;
 162         struct rcu_head rcu;
 163 };
 164
 165 static struct cds_lfq_queue_rcu q;
 166
 167 void *thr_enqueuer(void *_count)
 168 {
 169         unsigned long long *count = _count;
 170
 171         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 172                         "enqueuer", pthread_self(), (unsigned long)gettid());
 173
 174         set_affinity();
 175
 176         rcu_register_thread();
 177
 178         while (!test_go)
 179         {
 180         }
 181         cmm_smp_mb();
 182
 183         for (;;) {
 184                 struct test *node = malloc(sizeof(*node));
 185                 if (!node)
 186                         goto fail;
 187                 cds_lfq_node_init_rcu(&node->list);
 188                 rcu_read_lock();
 189                 cds_lfq_enqueue_rcu(&q, &node->list);
 190                 rcu_read_unlock();
 191                 URCU_TLS(nr_successful_enqueues)++;
 192
 193                 if (caa_unlikely(wdelay))
 194                         loop_sleep(wdelay);
 195 fail:
 196                 URCU_TLS(nr_enqueues)++;
 197                 if (caa_unlikely(!test_duration_enqueue()))
 198                         break;
 199         }
 200
 201         rcu_unregister_thread();
 202
 203         count[0] = URCU_TLS(nr_enqueues);
 204         count[1] = URCU_TLS(nr_successful_enqueues);
 205         printf_verbose("enqueuer thread_end, thread id : %lx, tid %lu, "
 206                        "enqueues %llu successful_enqueues %llu\n",
 207                        pthread_self(), (unsigned long)gettid(),
 208                        URCU_TLS(nr_enqueues), URCU_TLS(nr_successful_enqueues));
 209         return ((void*)1);
 210
 211 }
 212
 213 static
 214 void free_node_cb(struct rcu_head *head)
 215 {
 216         struct test *node =
 217                 caa_container_of(head, struct test, rcu);
 218         free(node);
 219 }
 220
 221 void *thr_dequeuer(void *_count)
 222 {
 223         unsigned long long *count = _count;
 224
 225         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 226                         "dequeuer", pthread_self(), (unsigned long)gettid());
 227
 228         set_affinity();
 229
 230         rcu_register_thread();
 231
 232         while (!test_go)
 233         {
 234         }
 235         cmm_smp_mb();
 236
 237         for (;;) {
 238                 struct cds_lfq_node_rcu *qnode;
 239
 240                 rcu_read_lock();
 241                 qnode = cds_lfq_dequeue_rcu(&q);
 242                 rcu_read_unlock();
 243
 244                 if (qnode) {
 245                         struct test *node;
 246
 247                         node = caa_container_of(qnode, struct test, list);
 248                         call_rcu(&node->rcu, free_node_cb);
 249                         URCU_TLS(nr_successful_dequeues)++;
 250                 }
 251
 252                 URCU_TLS(nr_dequeues)++;
 253                 if (caa_unlikely(!test_duration_dequeue()))
 254                         break;
 255                 if (caa_unlikely(rduration))
 256                         loop_sleep(rduration);
 257         }
 258
 259         rcu_unregister_thread();
 260         printf_verbose("dequeuer thread_end, thread id : %lx, tid %lu, "
 261                        "dequeues %llu, successful_dequeues %llu\n",
 262                        pthread_self(), (unsigned long)gettid(),
 263                        URCU_TLS(nr_dequeues), URCU_TLS(nr_successful_dequeues));
 264         count[0] = URCU_TLS(nr_dequeues);
 265         count[1] = URCU_TLS(nr_successful_dequeues);
 266         return ((void*)2);
 267 }
 268
 269 void test_end(struct cds_lfq_queue_rcu *q, unsigned long long *nr_dequeues)
 270 {
 271         struct cds_lfq_node_rcu *snode;
 272
 273         do {
 274                 snode = cds_lfq_dequeue_rcu(q);
 275                 if (snode) {
 276                         struct test *node;
 277
 278                         node = caa_container_of(snode, struct test, list);
 279                         free(node);     /* no more concurrent access */
 280                         (*nr_dequeues)++;
 281                 }
 282         } while (snode);
 283 }
 284
 285 void show_usage(int argc, char **argv)
 286 {
 287         printf("Usage : %s nr_dequeuers nr_enqueuers duration (s)", argv[0]);
 288         printf(" [-d delay] (enqueuer period (in loops))");
 289         printf(" [-c duration] (dequeuer period (in loops))");
 290         printf(" [-v] (verbose output)");
 291         printf(" [-a cpu#] [-a cpu#]... (affinity)");
 292         printf("\n");
 293 }
 294
 295 int main(int argc, char **argv)
 296 {
 297         int err;
 298         pthread_t *tid_enqueuer, *tid_dequeuer;
 299         void *tret;
 300         unsigned long long *count_enqueuer, *count_dequeuer;
 301         unsigned long long tot_enqueues = 0, tot_dequeues = 0;
 302         unsigned long long tot_successful_enqueues = 0,
 303                            tot_successful_dequeues = 0;
 304         unsigned long long end_dequeues = 0;
 305         int i, a;
 306
 307         if (argc < 4) {
 308                 show_usage(argc, argv);
 309                 return -1;
 310         }
 311
 312         err = sscanf(argv[1], "%u", &nr_dequeuers);
 313         if (err != 1) {
 314                 show_usage(argc, argv);
 315                 return -1;
 316         }
 317
 318         err = sscanf(argv[2], "%u", &nr_enqueuers);
 319         if (err != 1) {
 320                 show_usage(argc, argv);
 321                 return -1;
 322         }
 323
 324         err = sscanf(argv[3], "%lu", &duration);
 325         if (err != 1) {
 326                 show_usage(argc, argv);
 327                 return -1;
 328         }
 329
 330         for (i = 4; i < argc; i++) {
 331                 if (argv[i][0] != '-')
 332                         continue;
 333                 switch (argv[i][1]) {
 334                 case 'a':
 335                         if (argc < i + 2) {
 336                                 show_usage(argc, argv);
 337                                 return -1;
 338                         }
 339                         a = atoi(argv[++i]);
 340                         cpu_affinities[next_aff++] = a;
 341                         use_affinity = 1;
 342                         printf_verbose("Adding CPU %d affinity\n", a);
 343                         break;
 344                 case 'c':
 345                         if (argc < i + 2) {
 346                                 show_usage(argc, argv);
 347                                 return -1;
 348                         }
 349                         rduration = atol(argv[++i]);
 350                         break;
 351                 case 'd':
 352                         if (argc < i + 2) {
 353                                 show_usage(argc, argv);
 354                                 return -1;
 355                         }
 356                         wdelay = 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 enqueuers, "
 365                        "%u dequeuers.\n",
 366                        duration, nr_enqueuers, nr_dequeuers);
 367         printf_verbose("Writer delay : %lu loops.\n", rduration);
 368         printf_verbose("Reader duration : %lu loops.\n", wdelay);
 369         printf_verbose("thread %-6s, thread id : %lx, tid %lu\n",
 370                         "main", pthread_self(), (unsigned long)gettid());
 371
 372         tid_enqueuer = malloc(sizeof(*tid_enqueuer) * nr_enqueuers);
 373         tid_dequeuer = malloc(sizeof(*tid_dequeuer) * nr_dequeuers);
 374         count_enqueuer = malloc(2 * sizeof(*count_enqueuer) * nr_enqueuers);
 375         count_dequeuer = malloc(2 * sizeof(*count_dequeuer) * nr_dequeuers);
 376         cds_lfq_init_rcu(&q, call_rcu);
 377         err = create_all_cpu_call_rcu_data(0);
 378         if (err) {
 379                 printf("Per-CPU call_rcu() worker threads unavailable. Using default global worker thread.\n");
 380         }
 381
 382         next_aff = 0;
 383
 384         for (i = 0; i < nr_enqueuers; i++) {
 385                 err = pthread_create(&tid_enqueuer[i], NULL, thr_enqueuer,
 386                                      &count_enqueuer[2 * i]);
 387                 if (err != 0)
 388                         exit(1);
 389         }
 390         for (i = 0; i < nr_dequeuers; i++) {
 391                 err = pthread_create(&tid_dequeuer[i], NULL, thr_dequeuer,
 392                                      &count_dequeuer[2 * i]);
 393                 if (err != 0)
 394                         exit(1);
 395         }
 396
 397         cmm_smp_mb();
 398
 399         test_go = 1;
 400
 401         for (i = 0; i < duration; i++) {
 402                 sleep(1);
 403                 if (verbose_mode)
 404                         write (1, ".", 1);
 405         }
 406
 407         test_stop = 1;
 408
 409         for (i = 0; i < nr_enqueuers; i++) {
 410                 err = pthread_join(tid_enqueuer[i], &tret);
 411                 if (err != 0)
 412                         exit(1);
 413                 tot_enqueues += count_enqueuer[2 * i];
 414                 tot_successful_enqueues += count_enqueuer[2 * i + 1];
 415         }
 416         for (i = 0; i < nr_dequeuers; i++) {
 417                 err = pthread_join(tid_dequeuer[i], &tret);
 418                 if (err != 0)
 419                         exit(1);
 420                 tot_dequeues += count_dequeuer[2 * i];
 421                 tot_successful_dequeues += count_dequeuer[2 * i + 1];
 422         }
 423
 424         test_end(&q, &end_dequeues);
 425         err = cds_lfq_destroy_rcu(&q);
 426         assert(!err);
 427
 428         printf_verbose("total number of enqueues : %llu, dequeues %llu\n",
 429                        tot_enqueues, tot_dequeues);
 430         printf_verbose("total number of successful enqueues : %llu, "
 431                        "successful dequeues %llu\n",
 432                        tot_successful_enqueues, tot_successful_dequeues);
 433         printf("SUMMARY %-25s testdur %4lu nr_enqueuers %3u wdelay %6lu "
 434                 "nr_dequeuers %3u "
 435                 "rdur %6lu nr_enqueues %12llu nr_dequeues %12llu "
 436                 "successful enqueues %12llu successful dequeues %12llu "
 437                 "end_dequeues %llu nr_ops %12llu\n",
 438                 argv[0], duration, nr_enqueuers, wdelay,
 439                 nr_dequeuers, rduration, tot_enqueues, tot_dequeues,
 440                 tot_successful_enqueues,
 441                 tot_successful_dequeues, end_dequeues,
 442                 tot_enqueues + tot_dequeues);
 443         if (tot_successful_enqueues != tot_successful_dequeues + end_dequeues)
 444                 printf("WARNING! Discrepancy between nr succ. enqueues %llu vs "
 445                        "succ. dequeues + end dequeues %llu.\n",
 446                        tot_successful_enqueues,
 447                        tot_successful_dequeues + end_dequeues);
 448
 449         free_all_cpu_call_rcu_data();
 450         free(count_enqueuer);
 451         free(count_dequeuer);
 452         free(tid_enqueuer);
 453         free(tid_dequeuer);
 454         return 0;
 455 }