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 static void set_affinity(void)
 102 {
 103         cpu_set_t mask;
 104         int cpu;
 105
 106         if (!use_affinity)
 107                 return;
 108
 109         cpu = cpu_affinities[next_aff++];
 110         CPU_ZERO(&mask);
 111         CPU_SET(cpu, &mask);
 112         sched_setaffinity(0, sizeof(mask), &mask);
 113 }
 114
 115
 116
 117 /*
 118  * returns 0 if test should end.
 119  */
 120 static int test_duration_write(void)
 121 {
 122         return !test_stop;
 123 }
 124
 125 static int test_duration_read(void)
 126 {
 127         return !test_stop;
 128 }
 129
 130 static unsigned long long __thread nr_writes;
 131 static unsigned long long __thread nr_reads;
 132
 133 static
 134 unsigned long long __attribute__((aligned(CACHE_LINE_SIZE))) *tot_nr_writes;
 135 static
 136 unsigned long long __attribute__((aligned(CACHE_LINE_SIZE))) *tot_nr_reads;
 137
 138 static unsigned int nr_readers;
 139 static unsigned int nr_writers;
 140
 141 pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
 142
 143 void rcu_copy_mutex_lock(void)
 144 {
 145         int ret;
 146         ret = pthread_mutex_lock(&rcu_copy_mutex);
 147         if (ret) {
 148                 perror("Error in pthread mutex lock");
 149                 exit(-1);
 150         }
 151 }
 152
 153 void rcu_copy_mutex_unlock(void)
 154 {
 155         int ret;
 156
 157         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 158         if (ret) {
 159                 perror("Error in pthread mutex unlock");
 160                 exit(-1);
 161         }
 162 }
 163
 164 void *thr_reader(void *data)
 165 {
 166         unsigned long tidx = (unsigned long)data;
 167
 168         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 169                         "reader", pthread_self(), (unsigned long)gettid());
 170
 171         set_affinity();
 172
 173         while (!test_go)
 174         {
 175         }
 176
 177         for (;;) {
 178                 pthread_mutex_lock(&lock);
 179                 assert(test_array.a == 8);
 180                 if (unlikely(rduration))
 181                         loop_sleep(rduration);
 182                 pthread_mutex_unlock(&lock);
 183                 nr_reads++;
 184                 if (unlikely(!test_duration_read()))
 185                         break;
 186         }
 187
 188         tot_nr_reads[tidx] = nr_reads;
 189         printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
 190                         "reader", pthread_self(), (unsigned long)gettid());
 191         return ((void*)1);
 192
 193 }
 194
 195 void *thr_writer(void *data)
 196 {
 197         unsigned long wtidx = (unsigned long)data;
 198
 199         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 200                         "writer", pthread_self(), (unsigned long)gettid());
 201
 202         set_affinity();
 203
 204         while (!test_go)
 205         {
 206         }
 207         smp_mb();
 208
 209         for (;;) {
 210                 pthread_mutex_lock(&lock);
 211                 test_array.a = 0;
 212                 test_array.a = 8;
 213                 pthread_mutex_unlock(&lock);
 214                 nr_writes++;
 215                 if (unlikely(!test_duration_write()))
 216                         break;
 217                 if (unlikely(wdelay))
 218                         loop_sleep(wdelay);
 219         }
 220
 221         printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
 222                         "writer", pthread_self(), (unsigned long)gettid());
 223         tot_nr_writes[wtidx] = nr_writes;
 224         return ((void*)2);
 225 }
 226
 227 void show_usage(int argc, char **argv)
 228 {
 229         printf("Usage : %s nr_readers nr_writers duration (s)", argv[0]);
 230 #ifdef DEBUG_YIELD
 231         printf(" [-r] [-w] (yield reader and/or writer)");
 232 #endif
 233         printf(" [-d delay] (writer period (us))");
 234         printf(" [-c duration] (reader C.S. duration (in loops))");
 235         printf(" [-v] (verbose output)");
 236         printf(" [-a cpu#] [-a cpu#]... (affinity)");
 237         printf("\n");
 238 }
 239
 240 int main(int argc, char **argv)
 241 {
 242         int err;
 243         pthread_t *tid_reader, *tid_writer;
 244         void *tret;
 245         unsigned long long *count_reader, *count_writer;
 246         unsigned long long tot_reads = 0, tot_writes = 0;
 247         int i, a;
 248
 249         if (argc < 4) {
 250                 show_usage(argc, argv);
 251                 return -1;
 252         }
 253         smp_mb();
 254
 255         err = sscanf(argv[1], "%u", &nr_readers);
 256         if (err != 1) {
 257                 show_usage(argc, argv);
 258                 return -1;
 259         }
 260
 261         err = sscanf(argv[2], "%u", &nr_writers);
 262         if (err != 1) {
 263                 show_usage(argc, argv);
 264                 return -1;
 265         }
 266
 267         err = sscanf(argv[3], "%lu", &duration);
 268         if (err != 1) {
 269                 show_usage(argc, argv);
 270                 return -1;
 271         }
 272
 273         for (i = 4; i < argc; i++) {
 274                 if (argv[i][0] != '-')
 275                         continue;
 276                 switch (argv[i][1]) {
 277 #ifdef DEBUG_YIELD
 278                 case 'r':
 279                         yield_active |= YIELD_READ;
 280                         break;
 281                 case 'w':
 282                         yield_active |= YIELD_WRITE;
 283                         break;
 284 #endif
 285                 case 'a':
 286                         if (argc < i + 2) {
 287                                 show_usage(argc, argv);
 288                                 return -1;
 289                         }
 290                         a = atoi(argv[++i]);
 291                         cpu_affinities[next_aff++] = a;
 292                         use_affinity = 1;
 293                         printf_verbose("Adding CPU %d affinity\n", a);
 294                         break;
 295                 case 'c':
 296                         if (argc < i + 2) {
 297                                 show_usage(argc, argv);
 298                                 return -1;
 299                         }
 300                         rduration = atol(argv[++i]);
 301                         break;
 302                 case 'd':
 303                         if (argc < i + 2) {
 304                                 show_usage(argc, argv);
 305                                 return -1;
 306                         }
 307                         wdelay = atol(argv[++i]);
 308                         break;
 309                 case 'v':
 310                         verbose_mode = 1;
 311                         break;
 312                 }
 313         }
 314
 315         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 316                 duration, nr_readers, nr_writers);
 317         printf_verbose("Writer delay : %lu loops.\n", wdelay);
 318         printf_verbose("Reader duration : %lu loops.\n", rduration);
 319         printf_verbose("thread %-6s, thread id : %lx, tid %lu\n",
 320                         "main", pthread_self(), (unsigned long)gettid());
 321
 322         tid_reader = malloc(sizeof(*tid_reader) * nr_readers);
 323         tid_writer = malloc(sizeof(*tid_writer) * nr_writers);
 324         count_reader = malloc(sizeof(*count_reader) * nr_readers);
 325         count_writer = malloc(sizeof(*count_writer) * nr_writers);
 326         tot_nr_reads = malloc(sizeof(*tot_nr_reads) * nr_readers);
 327         tot_nr_writes = malloc(sizeof(*tot_nr_writes) * nr_writers);
 328
 329         next_aff = 0;
 330
 331         for (i = 0; i < nr_readers; i++) {
 332                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 333                                      (void *)(long)i);
 334                 if (err != 0)
 335                         exit(1);
 336         }
 337         for (i = 0; i < nr_writers; i++) {
 338                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 339                                      (void *)(long)i);
 340                 if (err != 0)
 341                         exit(1);
 342         }
 343
 344         smp_mb();
 345
 346         test_go = 1;
 347
 348         sleep(duration);
 349
 350         test_stop = 1;
 351
 352         for (i = 0; i < nr_readers; i++) {
 353                 err = pthread_join(tid_reader[i], &tret);
 354                 if (err != 0)
 355                         exit(1);
 356                 tot_reads += tot_nr_reads[i];
 357         }
 358         for (i = 0; i < nr_writers; i++) {
 359                 err = pthread_join(tid_writer[i], &tret);
 360                 if (err != 0)
 361                         exit(1);
 362                 tot_writes += tot_nr_writes[i];
 363         }
 364
 365         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 366                tot_writes);
 367         printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu "
 368                 "nr_writers %3u "
 369                 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
 370                 argv[0], duration, nr_readers, rduration,
 371                 nr_writers, wdelay, tot_reads, tot_writes,
 372                 tot_reads + tot_writes);
 373
 374         free(tid_reader);
 375         free(tid_writer);
 376         free(count_reader);
 377         free(count_writer);
 378         free(tot_nr_reads);
 379         free(tot_nr_writes);
 380         return 0;
 381 }