tests/test_urcu_defer.c

   1 /*
   2  * test_urcu_defer.c
   3  *
   4  * Userspace RCU library - test program (with automatic reclamation)
   5  *
   6  * Copyright February 2009 - 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 "../config.h"
  25 #include <stdio.h>
  26 #include <pthread.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <sys/types.h>
  30 #include <sys/wait.h>
  31 #include <unistd.h>
  32 #include <stdio.h>
  33 #include <assert.h>
  34 #include <sys/syscall.h>
  35 #include <sched.h>
  36 #include <errno.h>
  37
  38 #include <urcu/arch.h>
  39
  40 /* hardcoded number of CPUs */
  41 #define NR_CPUS 16384
  42
  43 #if defined(_syscall0)
  44 _syscall0(pid_t, gettid)
  45 #elif defined(__NR_gettid)
  46 static inline pid_t gettid(void)
  47 {
  48         return syscall(__NR_gettid);
  49 }
  50 #else
  51 #warning "use pid as tid"
  52 static inline pid_t gettid(void)
  53 {
  54         return getpid();
  55 }
  56 #endif
  57
  58 #ifndef DYNAMIC_LINK_TEST
  59 #define _LGPL_SOURCE
  60 #else
  61 #define debug_yield_read()
  62 #endif
  63 #include <urcu.h>
  64 #include <urcu-defer.h>
  65
  66 struct test_array {
  67         int a;
  68 };
  69
  70 static volatile int test_go, test_stop;
  71
  72 static unsigned long wdelay;
  73
  74 static struct test_array *test_rcu_pointer;
  75
  76 static unsigned long duration;
  77
  78 /* read-side C.S. duration, in loops */
  79 static unsigned long rduration;
  80
  81 static inline void loop_sleep(unsigned long l)
  82 {
  83         while(l-- != 0)
  84                 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 #ifndef HAVE_CPU_SET_T
 102 typedef unsigned long cpu_set_t;
 103 # define CPU_ZERO(cpuset) do { *(cpuset) = 0; } while(0)
 104 # define CPU_SET(cpu, cpuset) do { *(cpuset) |= (1UL << (cpu)); } while(0)
 105 #endif
 106
 107 static void set_affinity(void)
 108 {
 109         cpu_set_t mask;
 110         int cpu;
 111         int ret;
 112
 113         if (!use_affinity)
 114                 return;
 115
 116 #if HAVE_SCHED_SETAFFINITY
 117         ret = pthread_mutex_lock(&affinity_mutex);
 118         if (ret) {
 119                 perror("Error in pthread mutex lock");
 120                 exit(-1);
 121         }
 122         cpu = cpu_affinities[next_aff++];
 123         ret = pthread_mutex_unlock(&affinity_mutex);
 124         if (ret) {
 125                 perror("Error in pthread mutex unlock");
 126                 exit(-1);
 127         }
 128
 129         CPU_ZERO(&mask);
 130         CPU_SET(cpu, &mask);
 131 #if SCHED_SETAFFINITY_ARGS == 2
 132         sched_setaffinity(0, &mask);
 133 #else
 134         sched_setaffinity(0, sizeof(mask), &mask);
 135 #endif
 136 #endif /* HAVE_SCHED_SETAFFINITY */
 137 }
 138
 139 /*
 140  * returns 0 if test should end.
 141  */
 142 static int test_duration_write(void)
 143 {
 144         return !test_stop;
 145 }
 146
 147 static int test_duration_read(void)
 148 {
 149         return !test_stop;
 150 }
 151
 152 static unsigned long long __thread nr_writes;
 153 static unsigned long long __thread nr_reads;
 154
 155 static
 156 unsigned long long __attribute__((aligned(CACHE_LINE_SIZE))) *tot_nr_writes;
 157
 158 static unsigned int nr_readers;
 159 static unsigned int nr_writers;
 160
 161 pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
 162
 163 void rcu_copy_mutex_lock(void)
 164 {
 165         int ret;
 166         ret = pthread_mutex_lock(&rcu_copy_mutex);
 167         if (ret) {
 168                 perror("Error in pthread mutex lock");
 169                 exit(-1);
 170         }
 171 }
 172
 173 void rcu_copy_mutex_unlock(void)
 174 {
 175         int ret;
 176
 177         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 178         if (ret) {
 179                 perror("Error in pthread mutex unlock");
 180                 exit(-1);
 181         }
 182 }
 183
 184 void *thr_reader(void *_count)
 185 {
 186         unsigned long long *count = _count;
 187         struct test_array *local_ptr;
 188
 189         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 190                         "reader", pthread_self(), (unsigned long)gettid());
 191
 192         set_affinity();
 193
 194         rcu_register_thread();
 195
 196         while (!test_go)
 197         {
 198         }
 199         smp_mb();
 200
 201         for (;;) {
 202                 rcu_read_lock();
 203                 local_ptr = rcu_dereference(test_rcu_pointer);
 204                 debug_yield_read();
 205                 if (local_ptr)
 206                         assert(local_ptr->a == 8);
 207                 if (unlikely(rduration))
 208                         loop_sleep(rduration);
 209                 rcu_read_unlock();
 210                 nr_reads++;
 211                 if (unlikely(!test_duration_read()))
 212                         break;
 213         }
 214
 215         rcu_unregister_thread();
 216
 217         *count = nr_reads;
 218         printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
 219                         "reader", pthread_self(), (unsigned long)gettid());
 220         return ((void*)1);
 221
 222 }
 223
 224 static void test_cb2(void *data)
 225 {
 226 }
 227
 228 static void test_cb1(void *data)
 229 {
 230 }
 231
 232 void *thr_writer(void *data)
 233 {
 234         unsigned long wtidx = (unsigned long)data;
 235         struct test_array *new, *old = NULL;
 236
 237         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 238                         "writer", pthread_self(), (unsigned long)gettid());
 239
 240         set_affinity();
 241
 242         rcu_defer_register_thread();
 243
 244         while (!test_go)
 245         {
 246         }
 247         smp_mb();
 248
 249         for (;;) {
 250                 new = malloc(sizeof(*new));
 251                 new->a = 8;
 252                 old = rcu_xchg_pointer(&test_rcu_pointer, new);
 253                 defer_rcu(free, old);
 254                 defer_rcu(test_cb1, old);
 255                 defer_rcu(test_cb1, (void *)-2L);
 256                 defer_rcu(test_cb1, (void *)-2L);
 257                 defer_rcu(test_cb1, old);
 258                 defer_rcu(test_cb2, (void *)-2L);
 259                 defer_rcu(test_cb2, (void *)-4L);
 260                 defer_rcu(test_cb2, (void *)-2L);
 261                 nr_writes++;
 262                 if (unlikely(!test_duration_write()))
 263                         break;
 264                 if (unlikely(wdelay))
 265                         loop_sleep(wdelay);
 266         }
 267
 268         rcu_defer_unregister_thread();
 269
 270         printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
 271                         "writer", pthread_self(), (unsigned long)gettid());
 272         tot_nr_writes[wtidx] = nr_writes;
 273         return ((void*)2);
 274 }
 275
 276 void show_usage(int argc, char **argv)
 277 {
 278         printf("Usage : %s nr_readers nr_writers duration (s)", argv[0]);
 279 #ifdef DEBUG_YIELD
 280         printf(" [-r] [-w] (yield reader and/or writer)");
 281 #endif
 282         printf(" [-d delay] (writer period (us))");
 283         printf(" [-c duration] (reader C.S. duration (in loops))");
 284         printf(" [-v] (verbose output)");
 285         printf(" [-a cpu#] [-a cpu#]... (affinity)");
 286         printf("\n");
 287 }
 288
 289 int main(int argc, char **argv)
 290 {
 291         int err;
 292         pthread_t *tid_reader, *tid_writer;
 293         void *tret;
 294         unsigned long long *count_reader;
 295         unsigned long long tot_reads = 0, tot_writes = 0;
 296         int i, a;
 297
 298         if (argc < 4) {
 299                 show_usage(argc, argv);
 300                 return -1;
 301         }
 302
 303         err = sscanf(argv[1], "%u", &nr_readers);
 304         if (err != 1) {
 305                 show_usage(argc, argv);
 306                 return -1;
 307         }
 308
 309         err = sscanf(argv[2], "%u", &nr_writers);
 310         if (err != 1) {
 311                 show_usage(argc, argv);
 312                 return -1;
 313         }
 314
 315         err = sscanf(argv[3], "%lu", &duration);
 316         if (err != 1) {
 317                 show_usage(argc, argv);
 318                 return -1;
 319         }
 320
 321         for (i = 4; i < argc; i++) {
 322                 if (argv[i][0] != '-')
 323                         continue;
 324                 switch (argv[i][1]) {
 325 #ifdef DEBUG_YIELD
 326                 case 'r':
 327                         yield_active |= YIELD_READ;
 328                         break;
 329                 case 'w':
 330                         yield_active |= YIELD_WRITE;
 331                         break;
 332 #endif
 333                 case 'a':
 334                         if (argc < i + 2) {
 335                                 show_usage(argc, argv);
 336                                 return -1;
 337                         }
 338                         a = atoi(argv[++i]);
 339                         cpu_affinities[next_aff++] = a;
 340                         use_affinity = 1;
 341                         printf_verbose("Adding CPU %d affinity\n", a);
 342                         break;
 343                 case 'c':
 344                         if (argc < i + 2) {
 345                                 show_usage(argc, argv);
 346                                 return -1;
 347                         }
 348                         rduration = atol(argv[++i]);
 349                         break;
 350                 case 'd':
 351                         if (argc < i + 2) {
 352                                 show_usage(argc, argv);
 353                                 return -1;
 354                         }
 355                         wdelay = atol(argv[++i]);
 356                         break;
 357                 case 'v':
 358                         verbose_mode = 1;
 359                         break;
 360                 }
 361         }
 362
 363         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 364                 duration, nr_readers, nr_writers);
 365         printf_verbose("Writer delay : %lu loops.\n", wdelay);
 366         printf_verbose("Reader duration : %lu loops.\n", rduration);
 367         printf_verbose("thread %-6s, thread id : %lx, tid %lu\n",
 368                         "main", pthread_self(), (unsigned long)gettid());
 369
 370         tid_reader = malloc(sizeof(*tid_reader) * nr_readers);
 371         tid_writer = malloc(sizeof(*tid_writer) * nr_writers);
 372         count_reader = malloc(sizeof(*count_reader) * nr_readers);
 373         tot_nr_writes = malloc(sizeof(*tot_nr_writes) * nr_writers);
 374
 375         next_aff = 0;
 376
 377         for (i = 0; i < nr_readers; i++) {
 378                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 379                                      &count_reader[i]);
 380                 if (err != 0)
 381                         exit(1);
 382         }
 383         for (i = 0; i < nr_writers; i++) {
 384                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 385                                      (void *)(long)i);
 386                 if (err != 0)
 387                         exit(1);
 388         }
 389
 390         smp_mb();
 391
 392         test_go = 1;
 393
 394         sleep(duration);
 395
 396         test_stop = 1;
 397
 398         for (i = 0; i < nr_readers; i++) {
 399                 err = pthread_join(tid_reader[i], &tret);
 400                 if (err != 0)
 401                         exit(1);
 402                 tot_reads += count_reader[i];
 403         }
 404         for (i = 0; i < nr_writers; i++) {
 405                 err = pthread_join(tid_writer[i], &tret);
 406                 if (err != 0)
 407                         exit(1);
 408                 tot_writes += tot_nr_writes[i];
 409         }
 410
 411         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 412                tot_writes);
 413         printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu "
 414                 "nr_writers %3u "
 415                 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
 416                 argv[0], duration, nr_readers, rduration,
 417                 nr_writers, wdelay, tot_reads, tot_writes,
 418                 tot_reads + tot_writes);
 419         free(tid_reader);
 420         free(tid_writer);
 421         free(count_reader);
 422         free(tot_nr_writes);
 423
 424         return 0;
 425 }