test_mutex.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 static pthread_mutex_t lock;
  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 /*
  84  * returns 0 if test should end.
  85  */
  86 static int test_duration_write(void)
  87 {
  88         return !test_stop;
  89 }
  90
  91 static int test_duration_read(void)
  92 {
  93         return !test_stop;
  94 }
  95
  96 static unsigned long long __thread nr_writes;
  97 static unsigned long long __thread nr_reads;
  98
  99 static unsigned long long __attribute__((aligned(128))) *tot_nr_writes;
 100 static unsigned long long __attribute__((aligned(128))) *tot_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 *data)
 129 {
 130         unsigned long tidx = (unsigned long)data;
 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_mutex_lock(&lock);
 141                 assert(test_array.a == 8);
 142                 if (unlikely(rduration))
 143                         loop_sleep(rduration);
 144                 pthread_mutex_unlock(&lock);
 145                 nr_reads++;
 146                 if (unlikely(!test_duration_read()))
 147                         break;
 148         }
 149
 150         tot_nr_reads[tidx] = nr_reads;
 151         printf("thread_end %s, thread id : %lx, tid %lu\n",
 152                         "reader", pthread_self(), (unsigned long)gettid());
 153         return ((void*)1);
 154
 155 }
 156
 157 void *thr_writer(void *data)
 158 {
 159         unsigned long wtidx = (unsigned long)data;
 160
 161         printf("thread_begin %s, thread id : %lx, tid %lu\n",
 162                         "writer", pthread_self(), (unsigned long)gettid());
 163
 164         while (!test_go)
 165         {
 166         }
 167         smp_mb();
 168
 169         for (;;) {
 170                 pthread_mutex_lock(&lock);
 171                 test_array.a = 0;
 172                 test_array.a = 8;
 173                 pthread_mutex_unlock(&lock);
 174                 nr_writes++;
 175                 if (unlikely(!test_duration_write()))
 176                         break;
 177                 if (unlikely(wdelay))
 178                         usleep(wdelay);
 179         }
 180
 181         printf("thread_end %s, thread id : %lx, tid %lu\n",
 182                         "writer", pthread_self(), (unsigned long)gettid());
 183         tot_nr_writes[wtidx] = nr_writes;
 184         return ((void*)2);
 185 }
 186
 187 void show_usage(int argc, char **argv)
 188 {
 189         printf("Usage : %s nr_readers nr_writers duration (s)", argv[0]);
 190 #ifdef DEBUG_YIELD
 191         printf(" [-r] [-w] (yield reader and/or writer)");
 192 #endif
 193         printf(" [-d delay] (writer period (us))");
 194         printf(" [-c duration] (reader C.S. duration (in loops))");
 195         printf(" [-a cpu#] [-a cpu#]... (affinity)");
 196         printf("\n");
 197 }
 198
 199 cpu_set_t affinity;
 200
 201 int main(int argc, char **argv)
 202 {
 203         int err;
 204         pthread_t *tid_reader, *tid_writer;
 205         void *tret;
 206         unsigned long long *count_reader, *count_writer;
 207         unsigned long long tot_reads = 0, tot_writes = 0;
 208         int i, a;
 209         int use_affinity = 0;
 210
 211         if (argc < 4) {
 212                 show_usage(argc, argv);
 213                 return -1;
 214         }
 215         smp_mb();
 216
 217         err = sscanf(argv[1], "%u", &nr_readers);
 218         if (err != 1) {
 219                 show_usage(argc, argv);
 220                 return -1;
 221         }
 222
 223         err = sscanf(argv[2], "%u", &nr_writers);
 224         if (err != 1) {
 225                 show_usage(argc, argv);
 226                 return -1;
 227         }
 228
 229         err = sscanf(argv[3], "%lu", &duration);
 230         if (err != 1) {
 231                 show_usage(argc, argv);
 232                 return -1;
 233         }
 234
 235         CPU_ZERO(&affinity);
 236
 237         for (i = 4; i < argc; i++) {
 238                 if (argv[i][0] != '-')
 239                         continue;
 240                 switch (argv[i][1]) {
 241 #ifdef DEBUG_YIELD
 242                 case 'r':
 243                         yield_active |= YIELD_READ;
 244                         break;
 245                 case 'w':
 246                         yield_active |= YIELD_WRITE;
 247                         break;
 248 #endif
 249                 case 'a':
 250                         if (argc < i + 2) {
 251                                 show_usage(argc, argv);
 252                                 return -1;
 253                         }
 254                         a = atoi(argv[++i]);
 255                         CPU_SET(a, &affinity);
 256                         use_affinity = 1;
 257                         printf("Adding CPU %d affinity\n", a);
 258                         break;
 259                 case 'c':
 260                         if (argc < i + 2) {
 261                                 show_usage(argc, argv);
 262                                 return -1;
 263                         }
 264                         rduration = atoi(argv[++i]);
 265                         break;
 266                 case 'd':
 267                         if (argc < i + 2) {
 268                                 show_usage(argc, argv);
 269                                 return -1;
 270                         }
 271                         wdelay = atoi(argv[++i]);
 272                         break;
 273                 }
 274         }
 275
 276         printf("running test for %lu seconds, %u readers, %u writers.\n",
 277                 duration, nr_readers, nr_writers);
 278         printf("Writer delay : %u us.\n", wdelay);
 279         printf("thread %-6s, thread id : %lx, tid %lu\n",
 280                         "main", pthread_self(), (unsigned long)gettid());
 281
 282         if (use_affinity
 283             && sched_setaffinity(0, sizeof(affinity), &affinity) < 0) {
 284                 perror("sched_setaffinity");
 285                 exit(-1);
 286         }
 287
 288         tid_reader = malloc(sizeof(*tid_reader) * nr_readers);
 289         tid_writer = malloc(sizeof(*tid_writer) * nr_writers);
 290         count_reader = malloc(sizeof(*count_reader) * nr_readers);
 291         count_writer = malloc(sizeof(*count_writer) * nr_writers);
 292         tot_nr_reads = malloc(sizeof(*tot_nr_reads) * nr_readers);
 293         tot_nr_writes = malloc(sizeof(*tot_nr_writes) * nr_writers);
 294
 295         for (i = 0; i < nr_readers; i++) {
 296                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 297                                      (void *)(long)i);
 298                 if (err != 0)
 299                         exit(1);
 300         }
 301         for (i = 0; i < nr_writers; i++) {
 302                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 303                                      (void *)(long)i);
 304                 if (err != 0)
 305                         exit(1);
 306         }
 307
 308         smp_mb();
 309
 310         test_go = 1;
 311
 312         sleep(duration);
 313
 314         test_stop = 1;
 315
 316         for (i = 0; i < nr_readers; i++) {
 317                 err = pthread_join(tid_reader[i], &tret);
 318                 if (err != 0)
 319                         exit(1);
 320                 tot_reads += tot_nr_reads[i];
 321         }
 322         for (i = 0; i < nr_writers; i++) {
 323                 err = pthread_join(tid_writer[i], &tret);
 324                 if (err != 0)
 325                         exit(1);
 326                 tot_writes += tot_nr_writes[i];
 327         }
 328
 329         printf("total number of reads : %llu, writes %llu\n", tot_reads,
 330                tot_writes);
 331         free(tid_reader);
 332         free(tid_writer);
 333         free(count_reader);
 334         free(count_writer);
 335         free(tot_nr_reads);
 336         free(tot_nr_writes);
 337         return 0;
 338 }