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 #include <stdio.h>
  24 #include <pthread.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <sys/types.h>
  28 #include <sys/wait.h>
  29 #include <unistd.h>
  30 #include <stdio.h>
  31 #include <assert.h>
  32 #include <sys/syscall.h>
  33
  34 #include "arch.h"
  35
  36 #if defined(_syscall0)
  37 _syscall0(pid_t, gettid)
  38 #elif defined(__NR_gettid)
  39 static inline pid_t gettid(void)
  40 {
  41         return syscall(__NR_gettid);
  42 }
  43 #else
  44 #warning "use pid as tid"
  45 static inline pid_t gettid(void)
  46 {
  47         return getpid();
  48 }
  49 #endif
  50
  51 #ifndef DYNAMIC_LINK_TEST
  52 #define _LGPL_SOURCE
  53 #else
  54 #define debug_yield_read()
  55 #endif
  56 #include "urcu.h"
  57
  58 struct test_array {
  59         int a;
  60 };
  61
  62 pthread_rwlock_t lock = PTHREAD_RWLOCK_INITIALIZER;
  63
  64 static volatile int test_go;
  65
  66 static int wdelay;
  67
  68 static struct test_array test_array = { 8 };
  69
  70 static unsigned long duration;
  71 static time_t start_time;
  72 static unsigned long __thread duration_interval;
  73 #define DURATION_TEST_DELAY_WRITE 4
  74 #define DURATION_TEST_DELAY_READ 100
  75
  76 /*
  77  * returns 0 if test should end.
  78  */
  79 static int test_duration_write(void)
  80 {
  81         if (duration_interval++ >= DURATION_TEST_DELAY_WRITE) {
  82                 duration_interval = 0;
  83                 if (time(NULL) - start_time >= duration)
  84                         return 0;
  85         }
  86         return 1;
  87 }
  88
  89 static int test_duration_read(void)
  90 {
  91         if (duration_interval++ >= DURATION_TEST_DELAY_READ) {
  92                 duration_interval = 0;
  93                 if (time(NULL) - start_time >= duration)
  94                         return 0;
  95         }
  96         return 1;
  97 }
  98
  99 static unsigned long long __thread nr_writes;
 100 static unsigned long long __thread nr_reads;
 101
 102 static unsigned int nr_readers;
 103 static unsigned int nr_writers;
 104
 105 pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
 106
 107 void rcu_copy_mutex_lock(void)
 108 {
 109         int ret;
 110         ret = pthread_mutex_lock(&rcu_copy_mutex);
 111         if (ret) {
 112                 perror("Error in pthread mutex lock");
 113                 exit(-1);
 114         }
 115 }
 116
 117 void rcu_copy_mutex_unlock(void)
 118 {
 119         int ret;
 120
 121         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 122         if (ret) {
 123                 perror("Error in pthread mutex unlock");
 124                 exit(-1);
 125         }
 126 }
 127
 128 void *thr_reader(void *_count)
 129 {
 130         unsigned long long *count = _count;
 131
 132         printf("thread_begin %s, thread id : %lx, tid %lu\n",
 133                         "reader", pthread_self(), (unsigned long)gettid());
 134
 135         while (!test_go)
 136         {
 137         }
 138
 139         for (;;) {
 140                 pthread_rwlock_rdlock(&lock);
 141                 assert(test_array.a == 8);
 142                 pthread_rwlock_unlock(&lock);
 143                 nr_reads++;
 144                 if (!test_duration_read())
 145                         break;
 146         }
 147
 148         *count = nr_reads;
 149         printf("thread_end %s, thread id : %lx, tid %lu\n",
 150                         "reader", pthread_self(), (unsigned long)gettid());
 151         return ((void*)1);
 152
 153 }
 154
 155 void *thr_writer(void *_count)
 156 {
 157         unsigned long long *count = _count;
 158
 159         printf("thread_begin %s, thread id : %lx, tid %lu\n",
 160                         "writer", pthread_self(), (unsigned long)gettid());
 161
 162         while (!test_go)
 163         {
 164         }
 165         smp_mb();
 166
 167         for (;;) {
 168                 pthread_rwlock_wrlock(&lock);
 169                 test_array.a = 8;
 170                 pthread_rwlock_unlock(&lock);
 171                 nr_writes++;
 172                 if (!test_duration_write())
 173                         break;
 174                 if (wdelay)
 175                         usleep(wdelay);
 176         }
 177
 178         printf("thread_end %s, thread id : %lx, tid %lu\n",
 179                         "writer", pthread_self(), (unsigned long)gettid());
 180         *count = nr_writes;
 181         return ((void*)2);
 182 }
 183
 184 void show_usage(int argc, char **argv)
 185 {
 186         printf("Usage : %s nr_readers nr_writers duration (s)", argv[0]);
 187 #ifdef DEBUG_YIELD
 188         printf(" [-r] [-w] (yield reader and/or writer)");
 189 #endif
 190         printf(" [-d delay] (writer period (us))");
 191         printf("\n");
 192 }
 193
 194 int main(int argc, char **argv)
 195 {
 196         int err;
 197         pthread_t *tid_reader, *tid_writer;
 198         void *tret;
 199         unsigned long long *count_reader, *count_writer;
 200         unsigned long long tot_reads = 0, tot_writes = 0;
 201         int i;
 202
 203         if (argc < 4) {
 204                 show_usage(argc, argv);
 205                 return -1;
 206         }
 207         smp_mb();
 208
 209         err = sscanf(argv[1], "%u", &nr_readers);
 210         if (err != 1) {
 211                 show_usage(argc, argv);
 212                 return -1;
 213         }
 214
 215         err = sscanf(argv[2], "%u", &nr_writers);
 216         if (err != 1) {
 217                 show_usage(argc, argv);
 218                 return -1;
 219         }
 220
 221         err = sscanf(argv[3], "%lu", &duration);
 222         if (err != 1) {
 223                 show_usage(argc, argv);
 224                 return -1;
 225         }
 226
 227         for (i = 4; i < argc; i++) {
 228                 if (argv[i][0] != '-')
 229                         continue;
 230                 switch (argv[i][1]) {
 231 #ifdef DEBUG_YIELD
 232                 case 'r':
 233                         yield_active |= YIELD_READ;
 234                         break;
 235                 case 'w':
 236                         yield_active |= YIELD_WRITE;
 237                         break;
 238 #endif
 239                 case 'd':
 240                         if (argc < i + 2) {
 241                                 show_usage(argc, argv);
 242                                 return -1;
 243                         }
 244                         wdelay = atoi(argv[++i]);
 245                         break;
 246                 }
 247         }
 248
 249         printf("running test for %lu seconds, %u readers, %u writers.\n",
 250                 duration, nr_readers, nr_writers);
 251         printf("Writer delay : %u us.\n", wdelay);
 252         printf("thread %-6s, thread id : %lx, tid %lu\n",
 253                         "main", pthread_self(), (unsigned long)gettid());
 254
 255         tid_reader = malloc(sizeof(*tid_reader) * nr_readers);
 256         tid_writer = malloc(sizeof(*tid_writer) * nr_writers);
 257         count_reader = malloc(sizeof(*count_reader) * nr_readers);
 258         count_writer = malloc(sizeof(*count_writer) * nr_writers);
 259
 260         for (i = 0; i < nr_readers; i++) {
 261                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 262                                      &count_reader[i]);
 263                 if (err != 0)
 264                         exit(1);
 265         }
 266         for (i = 0; i < nr_writers; i++) {
 267                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 268                                      &count_writer[i]);
 269                 if (err != 0)
 270                         exit(1);
 271         }
 272
 273         start_time = time(NULL);
 274         test_go = 1;
 275         smp_mb();
 276
 277         for (i = 0; i < nr_readers; i++) {
 278                 err = pthread_join(tid_reader[i], &tret);
 279                 if (err != 0)
 280                         exit(1);
 281                 tot_reads += count_reader[i];
 282         }
 283         for (i = 0; i < nr_writers; i++) {
 284                 err = pthread_join(tid_writer[i], &tret);
 285                 if (err != 0)
 286                         exit(1);
 287                 tot_writes += count_writer[i];
 288         }
 289
 290         printf("total number of reads : %llu, writes %llu\n", tot_reads,
 291                tot_writes);
 292         free(tid_reader);
 293         free(tid_writer);
 294         free(count_reader);
 295         free(count_writer);
 296         return 0;
 297 }