tests/test_urcu_qsbr_gc.c

   1 /*
   2  * test_urcu_gc.c
   3  *
   4  * Userspace RCU library - test program (with baatch reclamation)
   5  *
   6  * Copyright February 2009 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   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 "../config.h"
  25 #include <stdio.h>
  26 #include <pthread.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <sys/types.h>
  30 #include <sys/wait.h>
  31 #include <unistd.h>
  32 #include <stdio.h>
  33 #include <assert.h>
  34 #include <sched.h>
  35 #include <errno.h>
  36
  37 #include <urcu/arch.h>
  38 #include <urcu/tls-compat.h>
  39
  40 #ifdef __linux__
  41 #include <syscall.h>
  42 #endif
  43
  44 /* hardcoded number of CPUs */
  45 #define NR_CPUS 16384
  46
  47 #if defined(_syscall0)
  48 _syscall0(pid_t, gettid)
  49 #elif defined(__NR_gettid)
  50 static inline pid_t gettid(void)
  51 {
  52         return syscall(__NR_gettid);
  53 }
  54 #else
  55 #warning "use pid as tid"
  56 static inline pid_t gettid(void)
  57 {
  58         return getpid();
  59 }
  60 #endif
  61
  62 #define _LGPL_SOURCE
  63 #include <urcu-qsbr.h>
  64
  65 struct test_array {
  66         int a;
  67 };
  68
  69 static volatile int test_go, test_stop;
  70
  71 static unsigned long wdelay;
  72
  73 static struct test_array *test_rcu_pointer;
  74
  75 static unsigned long duration;
  76
  77 /* read-side C.S. duration, in loops */
  78 static unsigned long rduration;
  79 static unsigned int reclaim_batch = 1;
  80
  81 struct reclaim_queue {
  82         void **queue;   /* Beginning of queue */
  83         void **head;    /* Insert position */
  84 };
  85
  86 static struct reclaim_queue *pending_reclaims;
  87
  88
  89 /* write-side C.S. duration, in loops */
  90 static unsigned long wduration;
  91
  92 static inline void loop_sleep(unsigned long l)
  93 {
  94         while(l-- != 0)
  95                 caa_cpu_relax();
  96 }
  97
  98 static int verbose_mode;
  99
 100 #define printf_verbose(fmt, args...)            \
 101         do {                                    \
 102                 if (verbose_mode)               \
 103                         printf(fmt, args);      \
 104         } while (0)
 105
 106 static unsigned int cpu_affinities[NR_CPUS];
 107 static unsigned int next_aff = 0;
 108 static int use_affinity = 0;
 109
 110 pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
 111
 112 #ifndef HAVE_CPU_SET_T
 113 typedef unsigned long cpu_set_t;
 114 # define CPU_ZERO(cpuset) do { *(cpuset) = 0; } while(0)
 115 # define CPU_SET(cpu, cpuset) do { *(cpuset) |= (1UL << (cpu)); } while(0)
 116 #endif
 117
 118 static void set_affinity(void)
 119 {
 120         cpu_set_t mask;
 121         int cpu;
 122         int ret;
 123
 124         if (!use_affinity)
 125                 return;
 126
 127 #if HAVE_SCHED_SETAFFINITY
 128         ret = pthread_mutex_lock(&affinity_mutex);
 129         if (ret) {
 130                 perror("Error in pthread mutex lock");
 131                 exit(-1);
 132         }
 133         cpu = cpu_affinities[next_aff++];
 134         ret = pthread_mutex_unlock(&affinity_mutex);
 135         if (ret) {
 136                 perror("Error in pthread mutex unlock");
 137                 exit(-1);
 138         }
 139
 140         CPU_ZERO(&mask);
 141         CPU_SET(cpu, &mask);
 142 #if SCHED_SETAFFINITY_ARGS == 2
 143         sched_setaffinity(0, &mask);
 144 #else
 145         sched_setaffinity(0, sizeof(mask), &mask);
 146 #endif
 147 #endif /* HAVE_SCHED_SETAFFINITY */
 148 }
 149
 150 /*
 151  * returns 0 if test should end.
 152  */
 153 static int test_duration_write(void)
 154 {
 155         return !test_stop;
 156 }
 157
 158 static int test_duration_read(void)
 159 {
 160         return !test_stop;
 161 }
 162
 163 static DEFINE_URCU_TLS(unsigned long long, nr_writes);
 164 static DEFINE_URCU_TLS(unsigned long long, nr_reads);
 165
 166 static unsigned int nr_readers;
 167 static unsigned int nr_writers;
 168
 169 pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
 170 static
 171 unsigned long long __attribute__((aligned(CAA_CACHE_LINE_SIZE))) *tot_nr_writes;
 172
 173
 174 void rcu_copy_mutex_lock(void)
 175 {
 176         int ret;
 177         ret = pthread_mutex_lock(&rcu_copy_mutex);
 178         if (ret) {
 179                 perror("Error in pthread mutex lock");
 180                 exit(-1);
 181         }
 182 }
 183
 184 void rcu_copy_mutex_unlock(void)
 185 {
 186         int ret;
 187
 188         ret = pthread_mutex_unlock(&rcu_copy_mutex);
 189         if (ret) {
 190                 perror("Error in pthread mutex unlock");
 191                 exit(-1);
 192         }
 193 }
 194
 195 void *thr_reader(void *_count)
 196 {
 197         unsigned long long *count = _count;
 198         struct test_array *local_ptr;
 199
 200         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 201                         "reader", (unsigned long) pthread_self(),
 202                         (unsigned long) gettid());
 203
 204         set_affinity();
 205
 206         rcu_register_thread();
 207
 208         while (!test_go)
 209         {
 210         }
 211         cmm_smp_mb();
 212
 213         for (;;) {
 214                 _rcu_read_lock();
 215                 local_ptr = _rcu_dereference(test_rcu_pointer);
 216                 debug_yield_read();
 217                 if (local_ptr)
 218                         assert(local_ptr->a == 8);
 219                 if (caa_unlikely(rduration))
 220                         loop_sleep(rduration);
 221                 _rcu_read_unlock();
 222                 URCU_TLS(nr_reads)++;
 223                 /* QS each 1024 reads */
 224                 if (caa_unlikely((URCU_TLS(nr_reads) & ((1 << 10) - 1)) == 0))
 225                         _rcu_quiescent_state();
 226                 if (caa_unlikely(!test_duration_read()))
 227                         break;
 228         }
 229
 230         rcu_unregister_thread();
 231
 232         *count = URCU_TLS(nr_reads);
 233         printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
 234                         "reader", (unsigned long) pthread_self(),
 235                         (unsigned long) gettid());
 236         return ((void*)1);
 237
 238 }
 239
 240 static void rcu_gc_clear_queue(unsigned long wtidx)
 241 {
 242         void **p;
 243
 244         /* Wait for Q.S and empty queue */
 245         synchronize_rcu();
 246
 247         for (p = pending_reclaims[wtidx].queue;
 248                         p < pending_reclaims[wtidx].head; p++) {
 249                 /* poison */
 250                 if (*p)
 251                         ((struct test_array *)*p)->a = 0;
 252                 free(*p);
 253         }
 254         pending_reclaims[wtidx].head = pending_reclaims[wtidx].queue;
 255 }
 256
 257 /* Using per-thread queue */
 258 static void rcu_gc_reclaim(unsigned long wtidx, void *old)
 259 {
 260         /* Queue pointer */
 261         *pending_reclaims[wtidx].head = old;
 262         pending_reclaims[wtidx].head++;
 263
 264         if (caa_likely(pending_reclaims[wtidx].head - pending_reclaims[wtidx].queue
 265                         < reclaim_batch))
 266                 return;
 267
 268         rcu_gc_clear_queue(wtidx);
 269 }
 270
 271 void *thr_writer(void *data)
 272 {
 273         unsigned long wtidx = (unsigned long)data;
 274 #ifdef TEST_LOCAL_GC
 275         struct test_array *old = NULL;
 276 #else
 277         struct test_array *new, *old;
 278 #endif
 279
 280         printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
 281                         "writer", (unsigned long) pthread_self(),
 282                         (unsigned long) gettid());
 283
 284         set_affinity();
 285
 286         while (!test_go)
 287         {
 288         }
 289         cmm_smp_mb();
 290
 291         for (;;) {
 292 #ifndef TEST_LOCAL_GC
 293                 new = malloc(sizeof(*new));
 294                 new->a = 8;
 295                 old = _rcu_xchg_pointer(&test_rcu_pointer, new);
 296 #endif
 297                 if (caa_unlikely(wduration))
 298                         loop_sleep(wduration);
 299                 rcu_gc_reclaim(wtidx, old);
 300                 URCU_TLS(nr_writes)++;
 301                 if (caa_unlikely(!test_duration_write()))
 302                         break;
 303                 if (caa_unlikely(wdelay))
 304                         loop_sleep(wdelay);
 305         }
 306
 307         printf_verbose("thread_end %s, thread id : %lx, tid %lu\n",
 308                         "writer", (unsigned long) pthread_self(),
 309                         (unsigned long) gettid());
 310         tot_nr_writes[wtidx] = URCU_TLS(nr_writes);
 311         return ((void*)2);
 312 }
 313
 314 void show_usage(int argc, char **argv)
 315 {
 316         printf("Usage : %s nr_readers nr_writers duration (s)", argv[0]);
 317 #ifdef DEBUG_YIELD
 318         printf(" [-r] [-w] (yield reader and/or writer)");
 319 #endif
 320         printf(" [-b batch] (batch reclaim)");
 321         printf(" [-d delay] (writer period (us))");
 322         printf(" [-c duration] (reader C.S. duration (in loops))");
 323         printf(" [-e duration] (writer C.S. duration (in loops))");
 324         printf(" [-v] (verbose output)");
 325         printf(" [-a cpu#] [-a cpu#]... (affinity)");
 326         printf("\n");
 327 }
 328
 329 int main(int argc, char **argv)
 330 {
 331         int err;
 332         pthread_t *tid_reader, *tid_writer;
 333         void *tret;
 334         unsigned long long *count_reader;
 335         unsigned long long tot_reads = 0, tot_writes = 0;
 336         int i, a;
 337
 338         if (argc < 4) {
 339                 show_usage(argc, argv);
 340                 return -1;
 341         }
 342
 343         err = sscanf(argv[1], "%u", &nr_readers);
 344         if (err != 1) {
 345                 show_usage(argc, argv);
 346                 return -1;
 347         }
 348
 349         err = sscanf(argv[2], "%u", &nr_writers);
 350         if (err != 1) {
 351                 show_usage(argc, argv);
 352                 return -1;
 353         }
 354
 355         err = sscanf(argv[3], "%lu", &duration);
 356         if (err != 1) {
 357                 show_usage(argc, argv);
 358                 return -1;
 359         }
 360
 361         for (i = 4; i < argc; i++) {
 362                 if (argv[i][0] != '-')
 363                         continue;
 364                 switch (argv[i][1]) {
 365 #ifdef DEBUG_YIELD
 366                 case 'r':
 367                         yield_active |= YIELD_READ;
 368                         break;
 369                 case 'w':
 370                         yield_active |= YIELD_WRITE;
 371                         break;
 372 #endif
 373                 case 'a':
 374                         if (argc < i + 2) {
 375                                 show_usage(argc, argv);
 376                                 return -1;
 377                         }
 378                         a = atoi(argv[++i]);
 379                         cpu_affinities[next_aff++] = a;
 380                         use_affinity = 1;
 381                         printf_verbose("Adding CPU %d affinity\n", a);
 382                         break;
 383                 case 'b':
 384                         if (argc < i + 2) {
 385                                 show_usage(argc, argv);
 386                                 return -1;
 387                         }
 388                         reclaim_batch = atol(argv[++i]);
 389                         break;
 390                 case 'c':
 391                         if (argc < i + 2) {
 392                                 show_usage(argc, argv);
 393                                 return -1;
 394                         }
 395                         rduration = atol(argv[++i]);
 396                         break;
 397                 case 'd':
 398                         if (argc < i + 2) {
 399                                 show_usage(argc, argv);
 400                                 return -1;
 401                         }
 402                         wdelay = atol(argv[++i]);
 403                         break;
 404                 case 'e':
 405                         if (argc < i + 2) {
 406                                 show_usage(argc, argv);
 407                                 return -1;
 408                         }
 409                         wduration = atol(argv[++i]);
 410                         break;
 411                 case 'v':
 412                         verbose_mode = 1;
 413                         break;
 414                 }
 415         }
 416
 417         printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
 418                 duration, nr_readers, nr_writers);
 419         printf_verbose("Writer delay : %lu loops.\n", wdelay);
 420         printf_verbose("Reader duration : %lu loops.\n", rduration);
 421         printf_verbose("thread %-6s, thread id : %lx, tid %lu\n",
 422                         "main", (unsigned long) pthread_self(),
 423                         (unsigned long) gettid());
 424
 425         tid_reader = malloc(sizeof(*tid_reader) * nr_readers);
 426         tid_writer = malloc(sizeof(*tid_writer) * nr_writers);
 427         count_reader = malloc(sizeof(*count_reader) * nr_readers);
 428         tot_nr_writes = malloc(sizeof(*tot_nr_writes) * nr_writers);
 429         pending_reclaims = malloc(sizeof(*pending_reclaims) * nr_writers);
 430         if (reclaim_batch * sizeof(*pending_reclaims[i].queue)
 431                         < CAA_CACHE_LINE_SIZE)
 432                 for (i = 0; i < nr_writers; i++)
 433                         pending_reclaims[i].queue = calloc(1, CAA_CACHE_LINE_SIZE);
 434         else
 435                 for (i = 0; i < nr_writers; i++)
 436                         pending_reclaims[i].queue = calloc(reclaim_batch,
 437                                         sizeof(*pending_reclaims[i].queue));
 438         for (i = 0; i < nr_writers; i++)
 439                 pending_reclaims[i].head = pending_reclaims[i].queue;
 440
 441         next_aff = 0;
 442
 443         for (i = 0; i < nr_readers; i++) {
 444                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 445                                      &count_reader[i]);
 446                 if (err != 0)
 447                         exit(1);
 448         }
 449         for (i = 0; i < nr_writers; i++) {
 450                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 451                                      (void *)(long)i);
 452                 if (err != 0)
 453                         exit(1);
 454         }
 455
 456         cmm_smp_mb();
 457
 458         test_go = 1;
 459
 460         sleep(duration);
 461
 462         test_stop = 1;
 463
 464         for (i = 0; i < nr_readers; i++) {
 465                 err = pthread_join(tid_reader[i], &tret);
 466                 if (err != 0)
 467                         exit(1);
 468                 tot_reads += count_reader[i];
 469         }
 470         for (i = 0; i < nr_writers; i++) {
 471                 err = pthread_join(tid_writer[i], &tret);
 472                 if (err != 0)
 473                         exit(1);
 474                 tot_writes += tot_nr_writes[i];
 475                 rcu_gc_clear_queue(i);
 476         }
 477
 478         printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
 479                tot_writes);
 480         printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu wdur %6lu "
 481                 "nr_writers %3u "
 482                 "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu "
 483                 "batch %u\n",
 484                 argv[0], duration, nr_readers, rduration, wduration,
 485                 nr_writers, wdelay, tot_reads, tot_writes,
 486                 tot_reads + tot_writes, reclaim_batch);
 487         free(tid_reader);
 488         free(tid_writer);
 489         free(count_reader);
 490         free(tot_nr_writes);
 491         for (i = 0; i < nr_writers; i++)
 492                 free(pending_reclaims[i].queue);
 493         free(pending_reclaims);
 494
 495         return 0;
 496 }