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