test_rwlock.c

   1 /*
   2  * test_urcu.c
   3  *
   4  * Userspace RCU library - test program
   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
  36 #include "arch.h"
  37
  38 #if defined(_syscall0)
  39 _syscall0(pid_t, gettid)
  40 #elif defined(__NR_gettid)
  41 static inline pid_t gettid(void)
  42 {
  43         return syscall(__NR_gettid);
  44 }
  45 #else
  46 #warning "use pid as tid"
  47 static inline pid_t gettid(void)
  48 {
  49         return getpid();
  50 }
  51 #endif
  52
  53 #ifndef DYNAMIC_LINK_TEST
  54 #define _LGPL_SOURCE
  55 #else
  56 #define debug_yield_read()
  57 #endif
  58 #include "urcu.h"
  59
  60 struct test_array {
  61         int a;
  62 };
  63
  64 pthread_rwlock_t lock = PTHREAD_RWLOCK_INITIALIZER;
  65
  66 static volatile int test_go, test_stop;
  67
  68 static int wdelay;
  69
  70 static volatile struct test_array test_array = { 8 };
  71
  72 static unsigned long duration;
  73
  74 /* read-side C.S. duration, in loops */
  75 static unsigned long rduration;
  76
  77 static inline void loop_sleep(unsigned long l)
  78 {
  79         while(l-- != 0)
  80                 cpu_relax();
  81 }
  82
  83 static int verbose_mode;
  84
  85 #define printf_verbose(fmt, args...)            \
  86         do {                                    \
  87                 if (verbose_mode)               \
  88                         printf(fmt, args);      \
  89         } while (0)
  90
  91 /*
  92  * returns 0 if test should end.
  93  */
  94 static int test_duration_write(void)
  95 {
  96         return !test_stop;
  97 }
  98
  99 static int test_duration_read(void)
 100 {
 101         return !test_stop;
 102 }
 103
 104 static unsigned long long __thread nr_writes;
 105 static unsigned long long __thread nr_reads;
 106
 107 static unsigned int nr_readers;
 108 static unsigned int nr_writers;
 109
 110 pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
 111
 112 void rcu_copy_mutex_lock(void)
 113 {
 114         int ret;
 115         ret = pthread_mutex_lock(&rcu_copy_mutex);
 116         if (ret) {
 117                 perror("Error in pthread mutex lock");
 118                 exit(-1);
 119         }
 120 }
 121
 122 void rcu_copy_mutex_unlock(void)
 123 {
 124         int ret;
 125
 126         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 127         if (ret) {
 128                 perror("Error in pthread mutex unlock");
 129                 exit(-1);
 130         }
 131 }
 132
 133 void *thr_reader(void *_count)
 134 {
 135         unsigned long long *count = _count;
 136
 137         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 138                         "reader", pthread_self(), (unsigned long)gettid());
 139
 140         while (!test_go)
 141         {
 142         }
 143
 144         for (;;) {
 145                 pthread_rwlock_rdlock(&lock);
 146                 assert(test_array.a == 8);
 147                 if (unlikely(rduration))
 148                         loop_sleep(rduration);
 149                 pthread_rwlock_unlock(&lock);
 150                 nr_reads++;
 151                 if (unlikely(!test_duration_read()))
 152                         break;
 153         }
 154
 155         *count = nr_reads;
 156         printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
 157                         "reader", pthread_self(), (unsigned long)gettid());
 158         return ((void*)1);
 159
 160 }
 161
 162 void *thr_writer(void *_count)
 163 {
 164         unsigned long long *count = _count;
 165
 166         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 167                         "writer", pthread_self(), (unsigned long)gettid());
 168
 169         while (!test_go)
 170         {
 171         }
 172         smp_mb();
 173
 174         for (;;) {
 175                 pthread_rwlock_wrlock(&lock);
 176                 test_array.a = 0;
 177                 test_array.a = 8;
 178                 pthread_rwlock_unlock(&lock);
 179                 nr_writes++;
 180                 if (unlikely(!test_duration_write()))
 181                         break;
 182                 if (unlikely(wdelay))
 183                         usleep(wdelay);
 184         }
 185
 186         printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
 187                         "writer", pthread_self(), (unsigned long)gettid());
 188         *count = nr_writes;
 189         return ((void*)2);
 190 }
 191
 192 void show_usage(int argc, char **argv)
 193 {
 194         printf("Usage : %s nr_readers nr_writers duration (s)", argv[0]);
 195 #ifdef DEBUG_YIELD
 196         printf(" [-r] [-w] (yield reader and/or writer)");
 197 #endif
 198         printf(" [-d delay] (writer period (us))");
 199         printf(" [-c duration] (reader C.S. duration (in loops))");
 200         printf(" [-v] (verbose output)");
 201         printf(" [-a cpu#] [-a cpu#]... (affinity)");
 202         printf("\n");
 203 }
 204
 205 cpu_set_t affinity;
 206
 207 int main(int argc, char **argv)
 208 {
 209         int err;
 210         pthread_t *tid_reader, *tid_writer;
 211         void *tret;
 212         unsigned long long *count_reader, *count_writer;
 213         unsigned long long tot_reads = 0, tot_writes = 0;
 214         int i, a;
 215         int use_affinity = 0;
 216
 217         if (argc < 4) {
 218                 show_usage(argc, argv);
 219                 return -1;
 220         }
 221         smp_mb();
 222
 223         err = sscanf(argv[1], "%u", &nr_readers);
 224         if (err != 1) {
 225                 show_usage(argc, argv);
 226                 return -1;
 227         }
 228
 229         err = sscanf(argv[2], "%u", &nr_writers);
 230         if (err != 1) {
 231                 show_usage(argc, argv);
 232                 return -1;
 233         }
 234
 235         err = sscanf(argv[3], "%lu", &duration);
 236         if (err != 1) {
 237                 show_usage(argc, argv);
 238                 return -1;
 239         }
 240
 241         CPU_ZERO(&affinity);
 242
 243         for (i = 4; i < argc; i++) {
 244                 if (argv[i][0] != '-')
 245                         continue;
 246                 switch (argv[i][1]) {
 247 #ifdef DEBUG_YIELD
 248                 case 'r':
 249                         yield_active |= YIELD_READ;
 250                         break;
 251                 case 'w':
 252                         yield_active |= YIELD_WRITE;
 253                         break;
 254 #endif
 255                 case 'a':
 256                         if (argc < i + 2) {
 257                                 show_usage(argc, argv);
 258                                 return -1;
 259                         }
 260                         a = atoi(argv[++i]);
 261                         CPU_SET(a, &affinity);
 262                         use_affinity = 1;
 263                         printf_verbose("Adding CPU %d affinity\n", a);
 264                         break;
 265                 case 'c':
 266                         if (argc < i + 2) {
 267                                 show_usage(argc, argv);
 268                                 return -1;
 269                         }
 270                         rduration = atoi(argv[++i]);
 271                         break;
 272                 case 'd':
 273                         if (argc < i + 2) {
 274                                 show_usage(argc, argv);
 275                                 return -1;
 276                         }
 277                         wdelay = atoi(argv[++i]);
 278                         break;
 279                 case 'v':
 280                         verbose_mode = 1;
 281                         break;
 282                 }
 283         }
 284
 285         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 286                 duration, nr_readers, nr_writers);
 287         printf_verbose("Writer delay : %u us.\n", wdelay);
 288         printf_verbose("Reader duration : %lu loops.\n", rduration);
 289         printf_verbose("thread %-6s, thread id : %lx, tid %lu\n",
 290                         "main", pthread_self(), (unsigned long)gettid());
 291         if (use_affinity
 292             && sched_setaffinity(0, sizeof(affinity), &affinity) < 0) {
 293                 perror("sched_setaffinity");
 294                 exit(-1);
 295         }
 296
 297         tid_reader = malloc(sizeof(*tid_reader) * nr_readers);
 298         tid_writer = malloc(sizeof(*tid_writer) * nr_writers);
 299         count_reader = malloc(sizeof(*count_reader) * nr_readers);
 300         count_writer = malloc(sizeof(*count_writer) * nr_writers);
 301
 302         for (i = 0; i < nr_readers; i++) {
 303                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 304                                      &count_reader[i]);
 305                 if (err != 0)
 306                         exit(1);
 307         }
 308         for (i = 0; i < nr_writers; i++) {
 309                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 310                                      &count_writer[i]);
 311                 if (err != 0)
 312                         exit(1);
 313         }
 314
 315         smp_mb();
 316
 317         test_go = 1;
 318
 319         sleep(duration);
 320
 321         test_stop = 1;
 322
 323         for (i = 0; i < nr_readers; i++) {
 324                 err = pthread_join(tid_reader[i], &tret);
 325                 if (err != 0)
 326                         exit(1);
 327                 tot_reads += count_reader[i];
 328         }
 329         for (i = 0; i < nr_writers; i++) {
 330                 err = pthread_join(tid_writer[i], &tret);
 331                 if (err != 0)
 332                         exit(1);
 333                 tot_writes += count_writer[i];
 334         }
 335
 336         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 337                tot_writes);
 338         printf("SUMMARY %-15s testdur %4lu nr_readers %3u rdur %6lu "
 339                 "nr_writers %3u "
 340                 "wdelay %4u nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
 341                 argv[0], duration, nr_readers, rduration,
 342                 nr_writers, wdelay, tot_reads, tot_writes,
 343                 tot_reads + tot_writes);
 344
 345         free(tid_reader);
 346         free(tid_writer);
 347         free(count_reader);
 348         free(count_writer);
 349         return 0;
 350 }