tests/benchmark/test_urcu_assign.c

   1 // SPDX-FileCopyrightText: 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   2 //
   3 // SPDX-License-Identifier: GPL-2.0-or-later
   4
   5 /*
   6  * Userspace RCU library - test program
   7  */
   8
   9 #include <stdio.h>
  10 #include <pthread.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <sys/types.h>
  14 #include <sys/wait.h>
  15 #include <unistd.h>
  16 #include <stdio.h>
  17 #include <errno.h>
  18
  19 #include <urcu/arch.h>
  20 #include <urcu/assert.h>
  21 #include <urcu/tls-compat.h>
  22 #include "thread-id.h"
  23 #include "../common/debug-yield.h"
  24
  25 /* hardcoded number of CPUs */
  26 #define NR_CPUS 16384
  27
  28 #ifndef DYNAMIC_LINK_TEST
  29 #define _LGPL_SOURCE
  30 #endif
  31 #include <urcu.h>
  32
  33 struct test_array {
  34         int a;
  35 };
  36
  37 static unsigned long wdelay;
  38
  39 static struct test_array *test_rcu_pointer;
  40
  41 static unsigned long duration;
  42
  43 /* read-side C.S. duration, in loops */
  44 static unsigned long rduration;
  45
  46 /* write-side C.S. duration, in loops */
  47 static unsigned long wduration;
  48
  49 static inline void loop_sleep(unsigned long loops)
  50 {
  51         while (loops-- != 0)
  52                 caa_cpu_relax();
  53 }
  54
  55 static int verbose_mode;
  56
  57 #define printf_verbose(fmt, args...)            \
  58         do {                                    \
  59                 if (verbose_mode)               \
  60                         printf(fmt, args);      \
  61         } while (0)
  62
  63 static unsigned int cpu_affinities[NR_CPUS];
  64 static unsigned int next_aff = 0;
  65 static int use_affinity = 0;
  66
  67 pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
  68
  69 static void set_affinity(void)
  70 {
  71 #ifdef HAVE_SCHED_SETAFFINITY
  72         cpu_set_t mask;
  73         int cpu, ret;
  74 #endif /* HAVE_SCHED_SETAFFINITY */
  75
  76         if (!use_affinity)
  77                 return;
  78
  79 #ifdef HAVE_SCHED_SETAFFINITY
  80         ret = pthread_mutex_lock(&affinity_mutex);
  81         if (ret) {
  82                 perror("Error in pthread mutex lock");
  83                 exit(-1);
  84         }
  85         cpu = cpu_affinities[next_aff++];
  86         ret = pthread_mutex_unlock(&affinity_mutex);
  87         if (ret) {
  88                 perror("Error in pthread mutex unlock");
  89                 exit(-1);
  90         }
  91
  92         CPU_ZERO(&mask);
  93         CPU_SET(cpu, &mask);
  94         sched_setaffinity(0, sizeof(mask), &mask);
  95 #endif /* HAVE_SCHED_SETAFFINITY */
  96 }
  97
  98 static DEFINE_URCU_TLS(unsigned long long, nr_writes);
  99 static DEFINE_URCU_TLS(unsigned long long, nr_reads);
 100
 101 static unsigned int nr_readers;
 102 static unsigned int nr_writers;
 103
 104 pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
 105
 106 static
 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 static
 118 void rcu_copy_mutex_unlock(void)
 119 {
 120         int ret;
 121
 122         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 123         if (ret) {
 124                 perror("Error in pthread mutex unlock");
 125                 exit(-1);
 126         }
 127 }
 128
 129 /*
 130  * malloc/free are reusing memory areas too quickly, which does not let us
 131  * test races appropriately. Use a large circular array for allocations.
 132  * ARRAY_SIZE is larger than nr_writers, and we keep the mutex across
 133  * both alloc and free, which insures we never run over our tail.
 134  */
 135 #define ARRAY_SIZE (1048576 * nr_writers)
 136 #define ARRAY_POISON (int) 0xDEADBEEF
 137 static unsigned int array_index;
 138 static struct test_array *test_array;
 139
 140 static struct test_array *test_array_alloc(void)
 141 {
 142         struct test_array *ret;
 143         int index;
 144
 145         index = array_index % ARRAY_SIZE;
 146         urcu_posix_assert(test_array[index].a == ARRAY_POISON ||
 147                 test_array[index].a == 0);
 148         ret = &test_array[index];
 149         array_index++;
 150         if (array_index == ARRAY_SIZE)
 151                 array_index = 0;
 152         return ret;
 153 }
 154
 155 static void test_array_free(struct test_array *ptr)
 156 {
 157         if (!ptr)
 158                 return;
 159         ptr->a = ARRAY_POISON;
 160 }
 161
 162 static
 163 void *thr_reader(void *_count)
 164 {
 165         unsigned long long *count = _count;
 166         struct test_array *local_ptr;
 167
 168         printf_verbose("thread_begin %s, tid %lu\n",
 169                         "reader", urcu_get_thread_id());
 170
 171         set_affinity();
 172
 173         rcu_register_thread();
 174
 175         wait_until_go();
 176
 177         for (;;) {
 178                 rcu_read_lock();
 179                 local_ptr = rcu_dereference(test_rcu_pointer);
 180                 rcu_debug_yield_read();
 181                 if (local_ptr)
 182                         urcu_posix_assert(local_ptr->a == 8);
 183                 if (caa_unlikely(rduration))
 184                         loop_sleep(rduration);
 185                 rcu_read_unlock();
 186                 URCU_TLS(nr_reads)++;
 187                 if (caa_unlikely(!test_duration_read()))
 188                         break;
 189         }
 190
 191         rcu_unregister_thread();
 192
 193         *count = URCU_TLS(nr_reads);
 194         printf_verbose("thread_end %s, tid %lu\n",
 195                         "reader", urcu_get_thread_id());
 196         return ((void*)1);
 197
 198 }
 199
 200 static
 201 void *thr_writer(void *_count)
 202 {
 203         unsigned long long *count = _count;
 204         struct test_array *new, *old;
 205
 206         printf_verbose("thread_begin %s, tid %lu\n",
 207                         "writer", urcu_get_thread_id());
 208
 209         set_affinity();
 210
 211         wait_until_go();
 212
 213         for (;;) {
 214                 rcu_copy_mutex_lock();
 215                 new = test_array_alloc();
 216                 new->a = 8;
 217                 old = test_rcu_pointer;
 218                 rcu_assign_pointer(test_rcu_pointer, new);
 219                 if (caa_unlikely(wduration))
 220                         loop_sleep(wduration);
 221                 synchronize_rcu();
 222                 if (old)
 223                         old->a = 0;
 224                 test_array_free(old);
 225                 rcu_copy_mutex_unlock();
 226                 URCU_TLS(nr_writes)++;
 227                 if (caa_unlikely(!test_duration_write()))
 228                         break;
 229                 if (caa_unlikely(wdelay))
 230                         loop_sleep(wdelay);
 231         }
 232
 233         printf_verbose("thread_end %s, tid %lu\n",
 234                         "writer", urcu_get_thread_id());
 235         *count = URCU_TLS(nr_writes);
 236         return ((void*)2);
 237 }
 238
 239 static
 240 void show_usage(char **argv)
 241 {
 242         printf("Usage : %s nr_readers nr_writers duration (s) <OPTIONS>\n",
 243                 argv[0]);
 244         printf("OPTIONS:\n");
 245         printf("        [-r] [-w] (yield reader and/or writer)\n");
 246         printf("        [-d delay] (writer period (us))\n");
 247         printf("        [-c duration] (reader C.S. duration (in loops))\n");
 248         printf("        [-e duration] (writer C.S. duration (in loops))\n");
 249         printf("        [-v] (verbose output)\n");
 250         printf("        [-a cpu#] [-a cpu#]... (affinity)\n");
 251         printf("\n");
 252 }
 253
 254 int main(int argc, char **argv)
 255 {
 256         int err;
 257         pthread_t *tid_reader, *tid_writer;
 258         void *tret;
 259         unsigned long long *count_reader, *count_writer;
 260         unsigned long long tot_reads = 0, tot_writes = 0;
 261         int i, a;
 262         unsigned int i_thr;
 263
 264         if (argc < 4) {
 265                 show_usage(argv);
 266                 return -1;
 267         }
 268
 269         err = sscanf(argv[1], "%u", &nr_readers);
 270         if (err != 1) {
 271                 show_usage(argv);
 272                 return -1;
 273         }
 274
 275         err = sscanf(argv[2], "%u", &nr_writers);
 276         if (err != 1) {
 277                 show_usage(argv);
 278                 return -1;
 279         }
 280
 281         err = sscanf(argv[3], "%lu", &duration);
 282         if (err != 1) {
 283                 show_usage(argv);
 284                 return -1;
 285         }
 286
 287         for (i = 4; i < argc; i++) {
 288                 if (argv[i][0] != '-')
 289                         continue;
 290                 switch (argv[i][1]) {
 291                 case 'r':
 292                         rcu_debug_yield_enable(RCU_YIELD_READ);
 293                         break;
 294                 case 'w':
 295                         rcu_debug_yield_enable(RCU_YIELD_WRITE);
 296                         break;
 297                 case 'a':
 298                         if (argc < i + 2) {
 299                                 show_usage(argv);
 300                                 return -1;
 301                         }
 302                         a = atoi(argv[++i]);
 303                         cpu_affinities[next_aff++] = a;
 304                         use_affinity = 1;
 305                         printf_verbose("Adding CPU %d affinity\n", a);
 306                         break;
 307                 case 'c':
 308                         if (argc < i + 2) {
 309                                 show_usage(argv);
 310                                 return -1;
 311                         }
 312                         rduration = atol(argv[++i]);
 313                         break;
 314                 case 'd':
 315                         if (argc < i + 2) {
 316                                 show_usage(argv);
 317                                 return -1;
 318                         }
 319                         wdelay = atol(argv[++i]);
 320                         break;
 321                 case 'e':
 322                         if (argc < i + 2) {
 323                                 show_usage(argv);
 324                                 return -1;
 325                         }
 326                         wduration = atol(argv[++i]);
 327                         break;
 328                 case 'v':
 329                         verbose_mode = 1;
 330                         break;
 331                 }
 332         }
 333
 334         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 335                 duration, nr_readers, nr_writers);
 336         printf_verbose("Writer delay : %lu loops.\n", wdelay);
 337         printf_verbose("Reader duration : %lu loops.\n", rduration);
 338         printf_verbose("thread %-6s, tid %lu\n",
 339                         "main", urcu_get_thread_id());
 340
 341         test_array = calloc(1, sizeof(*test_array) * ARRAY_SIZE);
 342         tid_reader = calloc(nr_readers, sizeof(*tid_reader));
 343         tid_writer = calloc(nr_writers, sizeof(*tid_writer));
 344         count_reader = calloc(nr_readers, sizeof(*count_reader));
 345         count_writer = calloc(nr_writers, sizeof(*count_writer));
 346
 347         next_aff = 0;
 348
 349         for (i_thr = 0; i_thr < nr_readers; i_thr++) {
 350                 err = pthread_create(&tid_reader[i_thr], NULL, thr_reader,
 351                                      &count_reader[i_thr]);
 352                 if (err != 0)
 353                         exit(1);
 354         }
 355         for (i_thr = 0; i_thr < nr_writers; i_thr++) {
 356                 err = pthread_create(&tid_writer[i_thr], NULL, thr_writer,
 357                                      &count_writer[i_thr]);
 358                 if (err != 0)
 359                         exit(1);
 360         }
 361
 362         test_for(duration);
 363
 364         for (i_thr = 0; i_thr < nr_readers; i_thr++) {
 365                 err = pthread_join(tid_reader[i_thr], &tret);
 366                 if (err != 0)
 367                         exit(1);
 368                 tot_reads += count_reader[i_thr];
 369         }
 370         for (i_thr = 0; i_thr < nr_writers; i_thr++) {
 371                 err = pthread_join(tid_writer[i_thr], &tret);
 372                 if (err != 0)
 373                         exit(1);
 374                 tot_writes += count_writer[i_thr];
 375         }
 376
 377         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 378                tot_writes);
 379         printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu wdur %6lu "
 380                 "nr_writers %3u "
 381                 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
 382                 argv[0], duration, nr_readers, rduration, wduration,
 383                 nr_writers, wdelay, tot_reads, tot_writes,
 384                 tot_reads + tot_writes);
 385
 386         test_array_free(test_rcu_pointer);
 387         free(test_array);
 388         free(tid_reader);
 389         free(tid_writer);
 390         free(count_reader);
 391         free(count_writer);
 392
 393         return 0;
 394 }