tests/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 /* Make this big enough to include the POWER5+ L3 cacheline size of 256B */
  39 #define CACHE_LINE_SIZE 4096
  40
  41 /* hardcoded number of CPUs */
  42 #define NR_CPUS 16384
  43
  44 #if defined(_syscall0)
  45 _syscall0(pid_t, gettid)
  46 #elif defined(__NR_gettid)
  47 static inline pid_t gettid(void)
  48 {
  49         return syscall(__NR_gettid);
  50 }
  51 #else
  52 #warning "use pid as tid"
  53 static inline pid_t gettid(void)
  54 {
  55         return getpid();
  56 }
  57 #endif
  58
  59 #ifndef DYNAMIC_LINK_TEST
  60 #define _LGPL_SOURCE
  61 #else
  62 #define debug_yield_read()
  63 #endif
  64 #include "../urcu.h"
  65
  66 struct test_array {
  67         int a;
  68 };
  69
  70 static pthread_mutex_t lock;
  71
  72 static volatile int test_go, test_stop;
  73
  74 static unsigned long wdelay;
  75
  76 static volatile struct test_array test_array = { 8 };
  77
  78 static unsigned long duration;
  79
  80 /* read-side C.S. duration, in loops */
  81 static unsigned long rduration;
  82
  83 static inline void loop_sleep(unsigned long l)
  84 {
  85         while(l-- != 0)
  86                 cpu_relax();
  87 }
  88
  89 static int verbose_mode;
  90
  91 #define printf_verbose(fmt, args...)            \
  92         do {                                    \
  93                 if (verbose_mode)               \
  94                         printf(fmt, args);      \
  95         } while (0)
  96
  97 static unsigned int cpu_affinities[NR_CPUS];
  98 static unsigned int next_aff = 0;
  99 static int use_affinity = 0;
 100
 101 pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
 102
 103 static void set_affinity(void)
 104 {
 105         cpu_set_t mask;
 106         int cpu;
 107         int ret;
 108
 109         if (!use_affinity)
 110                 return;
 111
 112         ret = pthread_mutex_lock(&affinity_mutex);
 113         if (ret) {
 114                 perror("Error in pthread mutex lock");
 115                 exit(-1);
 116         }
 117         cpu = cpu_affinities[next_aff++];
 118         ret = pthread_mutex_unlock(&affinity_mutex);
 119         if (ret) {
 120                 perror("Error in pthread mutex unlock");
 121                 exit(-1);
 122         }
 123         CPU_ZERO(&mask);
 124         CPU_SET(cpu, &mask);
 125         sched_setaffinity(0, sizeof(mask), &mask);
 126 }
 127
 128 /*
 129  * returns 0 if test should end.
 130  */
 131 static int test_duration_write(void)
 132 {
 133         return !test_stop;
 134 }
 135
 136 static int test_duration_read(void)
 137 {
 138         return !test_stop;
 139 }
 140
 141 static unsigned long long __thread nr_writes;
 142 static unsigned long long __thread nr_reads;
 143
 144 static
 145 unsigned long long __attribute__((aligned(CACHE_LINE_SIZE))) *tot_nr_writes;
 146 static
 147 unsigned long long __attribute__((aligned(CACHE_LINE_SIZE))) *tot_nr_reads;
 148
 149 static unsigned int nr_readers;
 150 static unsigned int nr_writers;
 151
 152 pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
 153
 154 void rcu_copy_mutex_lock(void)
 155 {
 156         int ret;
 157         ret = pthread_mutex_lock(&rcu_copy_mutex);
 158         if (ret) {
 159                 perror("Error in pthread mutex lock");
 160                 exit(-1);
 161         }
 162 }
 163
 164 void rcu_copy_mutex_unlock(void)
 165 {
 166         int ret;
 167
 168         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 169         if (ret) {
 170                 perror("Error in pthread mutex unlock");
 171                 exit(-1);
 172         }
 173 }
 174
 175 void *thr_reader(void *data)
 176 {
 177         unsigned long tidx = (unsigned long)data;
 178
 179         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 180                         "reader", pthread_self(), (unsigned long)gettid());
 181
 182         set_affinity();
 183
 184         while (!test_go)
 185         {
 186         }
 187
 188         for (;;) {
 189                 pthread_mutex_lock(&lock);
 190                 assert(test_array.a == 8);
 191                 if (unlikely(rduration))
 192                         loop_sleep(rduration);
 193                 pthread_mutex_unlock(&lock);
 194                 nr_reads++;
 195                 if (unlikely(!test_duration_read()))
 196                         break;
 197         }
 198
 199         tot_nr_reads[tidx] = nr_reads;
 200         printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
 201                         "reader", pthread_self(), (unsigned long)gettid());
 202         return ((void*)1);
 203
 204 }
 205
 206 void *thr_writer(void *data)
 207 {
 208         unsigned long wtidx = (unsigned long)data;
 209
 210         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 211                         "writer", pthread_self(), (unsigned long)gettid());
 212
 213         set_affinity();
 214
 215         while (!test_go)
 216         {
 217         }
 218         smp_mb();
 219
 220         for (;;) {
 221                 pthread_mutex_lock(&lock);
 222                 test_array.a = 0;
 223                 test_array.a = 8;
 224                 pthread_mutex_unlock(&lock);
 225                 nr_writes++;
 226                 if (unlikely(!test_duration_write()))
 227                         break;
 228                 if (unlikely(wdelay))
 229                         loop_sleep(wdelay);
 230         }
 231
 232         printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
 233                         "writer", pthread_self(), (unsigned long)gettid());
 234         tot_nr_writes[wtidx] = nr_writes;
 235         return ((void*)2);
 236 }
 237
 238 void show_usage(int argc, char **argv)
 239 {
 240         printf("Usage : %s nr_readers nr_writers duration (s)", argv[0]);
 241 #ifdef DEBUG_YIELD
 242         printf(" [-r] [-w] (yield reader and/or writer)");
 243 #endif
 244         printf(" [-d delay] (writer period (us))");
 245         printf(" [-c duration] (reader C.S. duration (in loops))");
 246         printf(" [-v] (verbose output)");
 247         printf(" [-a cpu#] [-a cpu#]... (affinity)");
 248         printf("\n");
 249 }
 250
 251 int main(int argc, char **argv)
 252 {
 253         int err;
 254         pthread_t *tid_reader, *tid_writer;
 255         void *tret;
 256         unsigned long long *count_reader, *count_writer;
 257         unsigned long long tot_reads = 0, tot_writes = 0;
 258         int i, a;
 259
 260         if (argc < 4) {
 261                 show_usage(argc, argv);
 262                 return -1;
 263         }
 264         smp_mb();
 265
 266         err = sscanf(argv[1], "%u", &nr_readers);
 267         if (err != 1) {
 268                 show_usage(argc, argv);
 269                 return -1;
 270         }
 271
 272         err = sscanf(argv[2], "%u", &nr_writers);
 273         if (err != 1) {
 274                 show_usage(argc, argv);
 275                 return -1;
 276         }
 277
 278         err = sscanf(argv[3], "%lu", &duration);
 279         if (err != 1) {
 280                 show_usage(argc, argv);
 281                 return -1;
 282         }
 283
 284         for (i = 4; i < argc; i++) {
 285                 if (argv[i][0] != '-')
 286                         continue;
 287                 switch (argv[i][1]) {
 288 #ifdef DEBUG_YIELD
 289                 case 'r':
 290                         yield_active |= YIELD_READ;
 291                         break;
 292                 case 'w':
 293                         yield_active |= YIELD_WRITE;
 294                         break;
 295 #endif
 296                 case 'a':
 297                         if (argc < i + 2) {
 298                                 show_usage(argc, argv);
 299                                 return -1;
 300                         }
 301                         a = atoi(argv[++i]);
 302                         cpu_affinities[next_aff++] = a;
 303                         use_affinity = 1;
 304                         printf_verbose("Adding CPU %d affinity\n", a);
 305                         break;
 306                 case 'c':
 307                         if (argc < i + 2) {
 308                                 show_usage(argc, argv);
 309                                 return -1;
 310                         }
 311                         rduration = atol(argv[++i]);
 312                         break;
 313                 case 'd':
 314                         if (argc < i + 2) {
 315                                 show_usage(argc, argv);
 316                                 return -1;
 317                         }
 318                         wdelay = atol(argv[++i]);
 319                         break;
 320                 case 'v':
 321                         verbose_mode = 1;
 322                         break;
 323                 }
 324         }
 325
 326         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 327                 duration, nr_readers, nr_writers);
 328         printf_verbose("Writer delay : %lu loops.\n", wdelay);
 329         printf_verbose("Reader duration : %lu loops.\n", rduration);
 330         printf_verbose("thread %-6s, thread id : %lx, tid %lu\n",
 331                         "main", pthread_self(), (unsigned long)gettid());
 332
 333         tid_reader = malloc(sizeof(*tid_reader) * nr_readers);
 334         tid_writer = malloc(sizeof(*tid_writer) * nr_writers);
 335         count_reader = malloc(sizeof(*count_reader) * nr_readers);
 336         count_writer = malloc(sizeof(*count_writer) * nr_writers);
 337         tot_nr_reads = malloc(sizeof(*tot_nr_reads) * nr_readers);
 338         tot_nr_writes = malloc(sizeof(*tot_nr_writes) * nr_writers);
 339
 340         next_aff = 0;
 341
 342         for (i = 0; i < nr_readers; i++) {
 343                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 344                                      (void *)(long)i);
 345                 if (err != 0)
 346                         exit(1);
 347         }
 348         for (i = 0; i < nr_writers; i++) {
 349                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 350                                      (void *)(long)i);
 351                 if (err != 0)
 352                         exit(1);
 353         }
 354
 355         smp_mb();
 356
 357         test_go = 1;
 358
 359         sleep(duration);
 360
 361         test_stop = 1;
 362
 363         for (i = 0; i < nr_readers; i++) {
 364                 err = pthread_join(tid_reader[i], &tret);
 365                 if (err != 0)
 366                         exit(1);
 367                 tot_reads += tot_nr_reads[i];
 368         }
 369         for (i = 0; i < nr_writers; i++) {
 370                 err = pthread_join(tid_writer[i], &tret);
 371                 if (err != 0)
 372                         exit(1);
 373                 tot_writes += tot_nr_writes[i];
 374         }
 375
 376         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 377                tot_writes);
 378         printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu "
 379                 "nr_writers %3u "
 380                 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
 381                 argv[0], duration, nr_readers, rduration,
 382                 nr_writers, wdelay, tot_reads, tot_writes,
 383                 tot_reads + tot_writes);
 384
 385         free(tid_reader);
 386         free(tid_writer);
 387         free(count_reader);
 388         free(count_writer);
 389         free(tot_nr_reads);
 390         free(tot_nr_writes);
 391         return 0;
 392 }