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 <stdio.h>
  25 #include <pthread.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <sys/types.h>
  29 #include <sys/wait.h>
  30 #include <unistd.h>
  31 #include <stdio.h>
  32 #include <assert.h>
  33 #include <sys/syscall.h>
  34 #include <sched.h>
  35 #include <errno.h>
  36
  37 #include <urcu/arch.h>
  38
  39 /* hardcoded number of CPUs */
  40 #define NR_CPUS 16384
  41
  42 #if defined(_syscall0)
  43 _syscall0(pid_t, gettid)
  44 #elif defined(__NR_gettid)
  45 static inline pid_t gettid(void)
  46 {
  47         return syscall(__NR_gettid);
  48 }
  49 #else
  50 #warning "use pid as tid"
  51 static inline pid_t gettid(void)
  52 {
  53         return getpid();
  54 }
  55 #endif
  56
  57 #ifndef DYNAMIC_LINK_TEST
  58 #define _LGPL_SOURCE
  59 #else
  60 #define debug_yield_read()
  61 #endif
  62 #include <urcu.h>
  63 #include <urcu-defer.h>
  64
  65 struct test_array {
  66         int a;
  67 };
  68
  69 static volatile int test_go, test_stop;
  70
  71 static unsigned long wdelay;
  72
  73 static struct test_array *test_rcu_pointer;
  74
  75 static unsigned long duration;
  76
  77 /* read-side C.S. duration, in loops */
  78 static unsigned long rduration;
  79
  80 static inline void loop_sleep(unsigned long l)
  81 {
  82         while(l-- != 0)
  83                 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 static void set_affinity(void)
 101 {
 102         cpu_set_t mask;
 103         int cpu;
 104         int ret;
 105
 106         if (!use_affinity)
 107                 return;
 108
 109         ret = pthread_mutex_lock(&affinity_mutex);
 110         if (ret) {
 111                 perror("Error in pthread mutex lock");
 112                 exit(-1);
 113         }
 114         cpu = cpu_affinities[next_aff++];
 115         ret = pthread_mutex_unlock(&affinity_mutex);
 116         if (ret) {
 117                 perror("Error in pthread mutex unlock");
 118                 exit(-1);
 119         }
 120         CPU_ZERO(&mask);
 121         CPU_SET(cpu, &mask);
 122         sched_setaffinity(0, sizeof(mask), &mask);
 123 }
 124
 125 /*
 126  * returns 0 if test should end.
 127  */
 128 static int test_duration_write(void)
 129 {
 130         return !test_stop;
 131 }
 132
 133 static int test_duration_read(void)
 134 {
 135         return !test_stop;
 136 }
 137
 138 static unsigned long long __thread nr_writes;
 139 static unsigned long long __thread nr_reads;
 140
 141 static
 142 unsigned long long __attribute__((aligned(CACHE_LINE_SIZE))) *tot_nr_writes;
 143
 144 static unsigned int nr_readers;
 145 static unsigned int nr_writers;
 146
 147 pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
 148
 149 void rcu_copy_mutex_lock(void)
 150 {
 151         int ret;
 152         ret = pthread_mutex_lock(&rcu_copy_mutex);
 153         if (ret) {
 154                 perror("Error in pthread mutex lock");
 155                 exit(-1);
 156         }
 157 }
 158
 159 void rcu_copy_mutex_unlock(void)
 160 {
 161         int ret;
 162
 163         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 164         if (ret) {
 165                 perror("Error in pthread mutex unlock");
 166                 exit(-1);
 167         }
 168 }
 169
 170 void *thr_reader(void *_count)
 171 {
 172         unsigned long long *count = _count;
 173         struct test_array *local_ptr;
 174
 175         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 176                         "reader", pthread_self(), (unsigned long)gettid());
 177
 178         set_affinity();
 179
 180         rcu_register_thread();
 181
 182         while (!test_go)
 183         {
 184         }
 185         smp_mb();
 186
 187         for (;;) {
 188                 rcu_read_lock();
 189                 local_ptr = rcu_dereference(test_rcu_pointer);
 190                 debug_yield_read();
 191                 if (local_ptr)
 192                         assert(local_ptr->a == 8);
 193                 if (unlikely(rduration))
 194                         loop_sleep(rduration);
 195                 rcu_read_unlock();
 196                 nr_reads++;
 197                 if (unlikely(!test_duration_read()))
 198                         break;
 199         }
 200
 201         rcu_unregister_thread();
 202
 203         *count = nr_reads;
 204         printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
 205                         "reader", pthread_self(), (unsigned long)gettid());
 206         return ((void*)1);
 207
 208 }
 209
 210 static void test_cb2(void *data)
 211 {
 212 }
 213
 214 static void test_cb1(void *data)
 215 {
 216 }
 217
 218 void *thr_writer(void *data)
 219 {
 220         unsigned long wtidx = (unsigned long)data;
 221         struct test_array *new, *old = NULL;
 222
 223         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 224                         "writer", pthread_self(), (unsigned long)gettid());
 225
 226         set_affinity();
 227
 228         rcu_defer_register_thread();
 229
 230         while (!test_go)
 231         {
 232         }
 233         smp_mb();
 234
 235         for (;;) {
 236                 new = malloc(sizeof(*new));
 237                 new->a = 8;
 238                 old = rcu_xchg_pointer(&test_rcu_pointer, new);
 239                 defer_rcu(free, old);
 240                 defer_rcu(test_cb1, old);
 241                 defer_rcu(test_cb1, (void *)-2L);
 242                 defer_rcu(test_cb1, (void *)-2L);
 243                 defer_rcu(test_cb1, old);
 244                 defer_rcu(test_cb2, (void *)-2L);
 245                 defer_rcu(test_cb2, (void *)-4L);
 246                 defer_rcu(test_cb2, (void *)-2L);
 247                 nr_writes++;
 248                 if (unlikely(!test_duration_write()))
 249                         break;
 250                 if (unlikely(wdelay))
 251                         loop_sleep(wdelay);
 252         }
 253
 254         rcu_defer_unregister_thread();
 255
 256         printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
 257                         "writer", pthread_self(), (unsigned long)gettid());
 258         tot_nr_writes[wtidx] = nr_writes;
 259         return ((void*)2);
 260 }
 261
 262 void show_usage(int argc, char **argv)
 263 {
 264         printf("Usage : %s nr_readers nr_writers duration (s)", argv[0]);
 265 #ifdef DEBUG_YIELD
 266         printf(" [-r] [-w] (yield reader and/or writer)");
 267 #endif
 268         printf(" [-d delay] (writer period (us))");
 269         printf(" [-c duration] (reader C.S. duration (in loops))");
 270         printf(" [-v] (verbose output)");
 271         printf(" [-a cpu#] [-a cpu#]... (affinity)");
 272         printf("\n");
 273 }
 274
 275 int main(int argc, char **argv)
 276 {
 277         int err;
 278         pthread_t *tid_reader, *tid_writer;
 279         void *tret;
 280         unsigned long long *count_reader;
 281         unsigned long long tot_reads = 0, tot_writes = 0;
 282         int i, a;
 283
 284         if (argc < 4) {
 285                 show_usage(argc, argv);
 286                 return -1;
 287         }
 288
 289         err = sscanf(argv[1], "%u", &nr_readers);
 290         if (err != 1) {
 291                 show_usage(argc, argv);
 292                 return -1;
 293         }
 294
 295         err = sscanf(argv[2], "%u", &nr_writers);
 296         if (err != 1) {
 297                 show_usage(argc, argv);
 298                 return -1;
 299         }
 300
 301         err = sscanf(argv[3], "%lu", &duration);
 302         if (err != 1) {
 303                 show_usage(argc, argv);
 304                 return -1;
 305         }
 306
 307         for (i = 4; i < argc; i++) {
 308                 if (argv[i][0] != '-')
 309                         continue;
 310                 switch (argv[i][1]) {
 311 #ifdef DEBUG_YIELD
 312                 case 'r':
 313                         yield_active |= YIELD_READ;
 314                         break;
 315                 case 'w':
 316                         yield_active |= YIELD_WRITE;
 317                         break;
 318 #endif
 319                 case 'a':
 320                         if (argc < i + 2) {
 321                                 show_usage(argc, argv);
 322                                 return -1;
 323                         }
 324                         a = atoi(argv[++i]);
 325                         cpu_affinities[next_aff++] = a;
 326                         use_affinity = 1;
 327                         printf_verbose("Adding CPU %d affinity\n", a);
 328                         break;
 329                 case 'c':
 330                         if (argc < i + 2) {
 331                                 show_usage(argc, argv);
 332                                 return -1;
 333                         }
 334                         rduration = atol(argv[++i]);
 335                         break;
 336                 case 'd':
 337                         if (argc < i + 2) {
 338                                 show_usage(argc, argv);
 339                                 return -1;
 340                         }
 341                         wdelay = atol(argv[++i]);
 342                         break;
 343                 case 'v':
 344                         verbose_mode = 1;
 345                         break;
 346                 }
 347         }
 348
 349         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 350                 duration, nr_readers, nr_writers);
 351         printf_verbose("Writer delay : %lu loops.\n", wdelay);
 352         printf_verbose("Reader duration : %lu loops.\n", rduration);
 353         printf_verbose("thread %-6s, thread id : %lx, tid %lu\n",
 354                         "main", pthread_self(), (unsigned long)gettid());
 355
 356         tid_reader = malloc(sizeof(*tid_reader) * nr_readers);
 357         tid_writer = malloc(sizeof(*tid_writer) * nr_writers);
 358         count_reader = malloc(sizeof(*count_reader) * nr_readers);
 359         tot_nr_writes = malloc(sizeof(*tot_nr_writes) * nr_writers);
 360
 361         next_aff = 0;
 362
 363         for (i = 0; i < nr_readers; i++) {
 364                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 365                                      &count_reader[i]);
 366                 if (err != 0)
 367                         exit(1);
 368         }
 369         for (i = 0; i < nr_writers; i++) {
 370                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 371                                      (void *)(long)i);
 372                 if (err != 0)
 373                         exit(1);
 374         }
 375
 376         smp_mb();
 377
 378         test_go = 1;
 379
 380         sleep(duration);
 381
 382         test_stop = 1;
 383
 384         for (i = 0; i < nr_readers; i++) {
 385                 err = pthread_join(tid_reader[i], &tret);
 386                 if (err != 0)
 387                         exit(1);
 388                 tot_reads += count_reader[i];
 389         }
 390         for (i = 0; i < nr_writers; i++) {
 391                 err = pthread_join(tid_writer[i], &tret);
 392                 if (err != 0)
 393                         exit(1);
 394                 tot_writes += tot_nr_writes[i];
 395         }
 396
 397         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 398                tot_writes);
 399         printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu "
 400                 "nr_writers %3u "
 401                 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
 402                 argv[0], duration, nr_readers, rduration,
 403                 nr_writers, wdelay, tot_reads, tot_writes,
 404                 tot_reads + tot_writes);
 405         free(tid_reader);
 406         free(tid_writer);
 407         free(count_reader);
 408         free(tot_nr_writes);
 409
 410         return 0;
 411 }