tests/rcutorture.h

   1 /*
   2  * rcutorture.h: simple user-level performance/stress test of RCU.
   3  *
   4  * Usage:
   5  *      ./rcu <nreaders> rperf [ <cpustride> ]
   6  *              Run a read-side performance test with the specified
   7  *              number of readers spaced by <cpustride>.
   8  *              Thus "./rcu 16 rperf 2" would run 16 readers on even-numbered
   9  *              CPUs from 0 to 30.
  10  *      ./rcu <nupdaters> uperf [ <cpustride> ]
  11  *              Run an update-side performance test with the specified
  12  *              number of updaters and specified CPU spacing.
  13  *      ./rcu <nreaders> perf [ <cpustride> ]
  14  *              Run a combined read/update performance test with the specified
  15  *              number of readers and one updater and specified CPU spacing.
  16  *              The readers run on the low-numbered CPUs and the updater
  17  *              of the highest-numbered CPU.
  18  *
  19  * The above tests produce output as follows:
  20  *
  21  * n_reads: 46008000  n_updates: 146026  nreaders: 2  nupdaters: 1 duration: 1
  22  * ns/read: 43.4707  ns/update: 6848.1
  23  *
  24  * The first line lists the total number of RCU reads and updates executed
  25  * during the test, the number of reader threads, the number of updater
  26  * threads, and the duration of the test in seconds.  The second line
  27  * lists the average duration of each type of operation in nanoseconds,
  28  * or "nan" if the corresponding type of operation was not performed.
  29  *
  30  *      ./rcu <nreaders> stress
  31  *              Run a stress test with the specified number of readers and
  32  *              one updater.  None of the threads are affinitied to any
  33  *              particular CPU.
  34  *
  35  * This test produces output as follows:
  36  *
  37  * n_reads: 114633217  n_updates: 3903415  n_mberror: 0
  38  * rcu_stress_count: 114618391 14826 0 0 0 0 0 0 0 0 0
  39  *
  40  * The first line lists the number of RCU read and update operations
  41  * executed, followed by the number of memory-ordering violations
  42  * (which will be zero in a correct RCU implementation).  The second
  43  * line lists the number of readers observing progressively more stale
  44  * data.  A correct RCU implementation will have all but the first two
  45  * numbers non-zero.
  46  *
  47  * This program is free software; you can redistribute it and/or modify
  48  * it under the terms of the GNU General Public License as published by
  49  * the Free Software Foundation; either version 2 of the License, or
  50  * (at your option) any later version.
  51  *
  52  * This program is distributed in the hope that it will be useful,
  53  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  54  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  55  * GNU General Public License for more details.
  56  *
  57  * You should have received a copy of the GNU General Public License
  58  * along with this program; if not, write to the Free Software
  59  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  60  *
  61  * Copyright (c) 2008 Paul E. McKenney, IBM Corporation.
  62  */
  63
  64 /*
  65  * Test variables.
  66  */
  67
  68 #include <stdlib.h>
  69
  70 DEFINE_PER_THREAD(long long, n_reads_pt);
  71 DEFINE_PER_THREAD(long long, n_updates_pt);
  72
  73 long long n_reads = 0LL;
  74 long n_updates = 0L;
  75 int nthreadsrunning;
  76 char argsbuf[64];
  77
  78 #define GOFLAG_INIT 0
  79 #define GOFLAG_RUN  1
  80 #define GOFLAG_STOP 2
  81
  82 int goflag __attribute__((__aligned__(CAA_CACHE_LINE_SIZE))) = GOFLAG_INIT;
  83
  84 #define RCU_READ_RUN 1000
  85
  86 //MD
  87 #define RCU_READ_NESTABLE
  88
  89 #ifdef RCU_READ_NESTABLE
  90 #define rcu_read_lock_nest() rcu_read_lock()
  91 #define rcu_read_unlock_nest() rcu_read_unlock()
  92 #else /* #ifdef RCU_READ_NESTABLE */
  93 #define rcu_read_lock_nest()
  94 #define rcu_read_unlock_nest()
  95 #endif /* #else #ifdef RCU_READ_NESTABLE */
  96
  97 #ifdef TORTURE_QSBR
  98 #define mark_rcu_quiescent_state        rcu_quiescent_state
  99 #define put_thread_offline              rcu_thread_offline
 100 #define put_thread_online               rcu_thread_online
 101 #endif
 102
 103 #ifndef mark_rcu_quiescent_state
 104 #define mark_rcu_quiescent_state() do ; while (0)
 105 #endif /* #ifdef mark_rcu_quiescent_state */
 106
 107 #ifndef put_thread_offline
 108 #define put_thread_offline()            do ; while (0)
 109 #define put_thread_online()             do ; while (0)
 110 #define put_thread_online_delay()       do ; while (0)
 111 #else /* #ifndef put_thread_offline */
 112 #define put_thread_online_delay()       synchronize_rcu()
 113 #endif /* #else #ifndef put_thread_offline */
 114
 115 /*
 116  * Performance test.
 117  */
 118
 119 void *rcu_read_perf_test(void *arg)
 120 {
 121         struct call_rcu_data *crdp;
 122         int i;
 123         int me = (long)arg;
 124         long long n_reads_local = 0;
 125
 126         rcu_register_thread();
 127         run_on(me);
 128         uatomic_inc(&nthreadsrunning);
 129         while (goflag == GOFLAG_INIT)
 130                 poll(NULL, 0, 1);
 131         mark_rcu_quiescent_state();
 132         while (goflag == GOFLAG_RUN) {
 133                 for (i = 0; i < RCU_READ_RUN; i++) {
 134                         rcu_read_lock();
 135                         /* rcu_read_lock_nest(); */
 136                         /* rcu_read_unlock_nest(); */
 137                         rcu_read_unlock();
 138                 }
 139                 n_reads_local += RCU_READ_RUN;
 140                 mark_rcu_quiescent_state();
 141         }
 142         __get_thread_var(n_reads_pt) += n_reads_local;
 143         put_thread_offline();
 144         crdp = get_thread_call_rcu_data();
 145         set_thread_call_rcu_data(NULL);
 146         call_rcu_data_free(crdp);
 147         rcu_unregister_thread();
 148
 149         return (NULL);
 150 }
 151
 152 void *rcu_update_perf_test(void *arg)
 153 {
 154         long long n_updates_local = 0;
 155
 156         if ((random() & 0xf00) == 0) {
 157                 struct call_rcu_data *crdp;
 158
 159                 crdp = create_call_rcu_data(0);
 160                 if (crdp != NULL) {
 161                         fprintf(stderr,
 162                                 "Using per-thread call_rcu() worker.\n");
 163                         set_thread_call_rcu_data(crdp);
 164                 }
 165         }
 166         uatomic_inc(&nthreadsrunning);
 167         while (goflag == GOFLAG_INIT)
 168                 poll(NULL, 0, 1);
 169         while (goflag == GOFLAG_RUN) {
 170                 synchronize_rcu();
 171                 n_updates_local++;
 172         }
 173         __get_thread_var(n_updates_pt) += n_updates_local;
 174         return NULL;
 175 }
 176
 177 void perftestinit(void)
 178 {
 179         init_per_thread(n_reads_pt, 0LL);
 180         init_per_thread(n_updates_pt, 0LL);
 181         uatomic_set(&nthreadsrunning, 0);
 182 }
 183
 184 void perftestrun(int nthreads, int nreaders, int nupdaters)
 185 {
 186         int t;
 187         int duration = 1;
 188
 189         cmm_smp_mb();
 190         while (uatomic_read(&nthreadsrunning) < nthreads)
 191                 poll(NULL, 0, 1);
 192         goflag = GOFLAG_RUN;
 193         cmm_smp_mb();
 194         sleep(duration);
 195         cmm_smp_mb();
 196         goflag = GOFLAG_STOP;
 197         cmm_smp_mb();
 198         wait_all_threads();
 199         for_each_thread(t) {
 200                 n_reads += per_thread(n_reads_pt, t);
 201                 n_updates += per_thread(n_updates_pt, t);
 202         }
 203         printf("n_reads: %lld  n_updates: %ld  nreaders: %d  nupdaters: %d duration: %d\n",
 204                n_reads, n_updates, nreaders, nupdaters, duration);
 205         printf("ns/read: %g  ns/update: %g\n",
 206                ((duration * 1000*1000*1000.*(double)nreaders) /
 207                 (double)n_reads),
 208                ((duration * 1000*1000*1000.*(double)nupdaters) /
 209                 (double)n_updates));
 210         if (get_cpu_call_rcu_data(0)) {
 211                 fprintf(stderr, "Deallocating per-CPU call_rcu threads.\n");
 212                 free_all_cpu_call_rcu_data();
 213         }
 214         exit(0);
 215 }
 216
 217 void perftest(int nreaders, int cpustride)
 218 {
 219         int i;
 220         long arg;
 221
 222         perftestinit();
 223         for (i = 0; i < nreaders; i++) {
 224                 arg = (long)(i * cpustride);
 225                 create_thread(rcu_read_perf_test, (void *)arg);
 226         }
 227         arg = (long)(i * cpustride);
 228         create_thread(rcu_update_perf_test, (void *)arg);
 229         perftestrun(i + 1, nreaders, 1);
 230 }
 231
 232 void rperftest(int nreaders, int cpustride)
 233 {
 234         int i;
 235         long arg;
 236
 237         perftestinit();
 238         init_per_thread(n_reads_pt, 0LL);
 239         for (i = 0; i < nreaders; i++) {
 240                 arg = (long)(i * cpustride);
 241                 create_thread(rcu_read_perf_test, (void *)arg);
 242         }
 243         perftestrun(i, nreaders, 0);
 244 }
 245
 246 void uperftest(int nupdaters, int cpustride)
 247 {
 248         int i;
 249         long arg;
 250
 251         perftestinit();
 252         init_per_thread(n_reads_pt, 0LL);
 253         for (i = 0; i < nupdaters; i++) {
 254                 arg = (long)(i * cpustride);
 255                 create_thread(rcu_update_perf_test, (void *)arg);
 256         }
 257         perftestrun(i, 0, nupdaters);
 258 }
 259
 260 /*
 261  * Stress test.
 262  */
 263
 264 #define RCU_STRESS_PIPE_LEN 10
 265
 266 struct rcu_stress {
 267         int pipe_count;
 268         int mbtest;
 269 };
 270
 271 struct rcu_stress rcu_stress_array[RCU_STRESS_PIPE_LEN] = { { 0 } };
 272 struct rcu_stress *rcu_stress_current;
 273 int rcu_stress_idx = 0;
 274
 275 int n_mberror = 0;
 276 DEFINE_PER_THREAD(long long [RCU_STRESS_PIPE_LEN + 1], rcu_stress_count);
 277
 278 int garbage = 0;
 279
 280 void *rcu_read_stress_test(void *arg)
 281 {
 282         int i;
 283         int itercnt = 0;
 284         struct rcu_stress *p;
 285         int pc;
 286
 287         rcu_register_thread();
 288         while (goflag == GOFLAG_INIT)
 289                 poll(NULL, 0, 1);
 290         mark_rcu_quiescent_state();
 291         while (goflag == GOFLAG_RUN) {
 292                 rcu_read_lock();
 293                 p = rcu_dereference(rcu_stress_current);
 294                 if (p->mbtest == 0)
 295                         n_mberror++;
 296                 rcu_read_lock_nest();
 297                 for (i = 0; i < 100; i++)
 298                         garbage++;
 299                 rcu_read_unlock_nest();
 300                 pc = p->pipe_count;
 301                 rcu_read_unlock();
 302                 if ((pc > RCU_STRESS_PIPE_LEN) || (pc < 0))
 303                         pc = RCU_STRESS_PIPE_LEN;
 304                 __get_thread_var(rcu_stress_count)[pc]++;
 305                 __get_thread_var(n_reads_pt)++;
 306                 mark_rcu_quiescent_state();
 307                 if ((++itercnt % 0x1000) == 0) {
 308                         put_thread_offline();
 309                         put_thread_online_delay();
 310                         put_thread_online();
 311                 }
 312         }
 313         put_thread_offline();
 314         rcu_unregister_thread();
 315
 316         return (NULL);
 317 }
 318
 319 static pthread_mutex_t call_rcu_test_mutex = PTHREAD_MUTEX_INITIALIZER;
 320 static pthread_cond_t call_rcu_test_cond = PTHREAD_COND_INITIALIZER;
 321
 322 void rcu_update_stress_test_rcu(struct rcu_head *head)
 323 {
 324         if (pthread_mutex_lock(&call_rcu_test_mutex) != 0) {
 325                 perror("pthread_mutex_lock");
 326                 exit(-1);
 327         }
 328         if (pthread_cond_signal(&call_rcu_test_cond) != 0) {
 329                 perror("pthread_cond_signal");
 330                 exit(-1);
 331         }
 332         if (pthread_mutex_unlock(&call_rcu_test_mutex) != 0) {
 333                 perror("pthread_mutex_unlock");
 334                 exit(-1);
 335         }
 336 }
 337
 338 void *rcu_update_stress_test(void *arg)
 339 {
 340         int i;
 341         struct rcu_stress *p;
 342         struct rcu_head rh;
 343
 344         while (goflag == GOFLAG_INIT)
 345                 poll(NULL, 0, 1);
 346         while (goflag == GOFLAG_RUN) {
 347                 i = rcu_stress_idx + 1;
 348                 if (i >= RCU_STRESS_PIPE_LEN)
 349                         i = 0;
 350                 p = &rcu_stress_array[i];
 351                 p->mbtest = 0;
 352                 cmm_smp_mb();
 353                 p->pipe_count = 0;
 354                 p->mbtest = 1;
 355                 rcu_assign_pointer(rcu_stress_current, p);
 356                 rcu_stress_idx = i;
 357                 for (i = 0; i < RCU_STRESS_PIPE_LEN; i++)
 358                         if (i != rcu_stress_idx)
 359                                 rcu_stress_array[i].pipe_count++;
 360                 if (n_updates & 0x1)
 361                         synchronize_rcu();
 362                 else {
 363                         if (pthread_mutex_lock(&call_rcu_test_mutex) != 0) {
 364                                 perror("pthread_mutex_lock");
 365                                 exit(-1);
 366                         }
 367                         call_rcu(&rh, rcu_update_stress_test_rcu);
 368                         if (pthread_cond_wait(&call_rcu_test_cond,
 369                                               &call_rcu_test_mutex) != 0) {
 370                                 perror("pthread_cond_wait");
 371                                 exit(-1);
 372                         }
 373                         if (pthread_mutex_unlock(&call_rcu_test_mutex) != 0) {
 374                                 perror("pthread_mutex_unlock");
 375                                 exit(-1);
 376                         }
 377                 }
 378                 n_updates++;
 379         }
 380         return NULL;
 381 }
 382
 383 void *rcu_fake_update_stress_test(void *arg)
 384 {
 385         if ((random() & 0xf00) == 0) {
 386                 struct call_rcu_data *crdp;
 387
 388                 crdp = create_call_rcu_data(0);
 389                 if (crdp != NULL) {
 390                         fprintf(stderr,
 391                                 "Using per-thread call_rcu() worker.\n");
 392                         set_thread_call_rcu_data(crdp);
 393                 }
 394         }
 395         while (goflag == GOFLAG_INIT)
 396                 poll(NULL, 0, 1);
 397         while (goflag == GOFLAG_RUN) {
 398                 synchronize_rcu();
 399                 poll(NULL, 0, 1);
 400         }
 401         return NULL;
 402 }
 403
 404 void stresstest(int nreaders)
 405 {
 406         int i;
 407         int t;
 408         long long *p;
 409         long long sum;
 410
 411         init_per_thread(n_reads_pt, 0LL);
 412         for_each_thread(t) {
 413                 p = &per_thread(rcu_stress_count,t)[0];
 414                 for (i = 0; i <= RCU_STRESS_PIPE_LEN; i++)
 415                         p[i] = 0LL;
 416         }
 417         rcu_stress_current = &rcu_stress_array[0];
 418         rcu_stress_current->pipe_count = 0;
 419         rcu_stress_current->mbtest = 1;
 420         for (i = 0; i < nreaders; i++)
 421                 create_thread(rcu_read_stress_test, NULL);
 422         create_thread(rcu_update_stress_test, NULL);
 423         for (i = 0; i < 5; i++)
 424                 create_thread(rcu_fake_update_stress_test, NULL);
 425         cmm_smp_mb();
 426         goflag = GOFLAG_RUN;
 427         cmm_smp_mb();
 428         sleep(10);
 429         cmm_smp_mb();
 430         goflag = GOFLAG_STOP;
 431         cmm_smp_mb();
 432         wait_all_threads();
 433         for_each_thread(t)
 434                 n_reads += per_thread(n_reads_pt, t);
 435         printf("n_reads: %lld  n_updates: %ld  n_mberror: %d\n",
 436                n_reads, n_updates, n_mberror);
 437         printf("rcu_stress_count:");
 438         for (i = 0; i <= RCU_STRESS_PIPE_LEN; i++) {
 439                 sum = 0LL;
 440                 for_each_thread(t) {
 441                         sum += per_thread(rcu_stress_count, t)[i];
 442                 }
 443                 printf(" %lld", sum);
 444         }
 445         printf("\n");
 446         if (get_cpu_call_rcu_data(0)) {
 447                 fprintf(stderr, "Deallocating per-CPU call_rcu threads.\n");
 448                 free_all_cpu_call_rcu_data();
 449         }
 450         exit(0);
 451 }
 452
 453 /*
 454  * Mainprogram.
 455  */
 456
 457 void usage(int argc, char *argv[])
 458 {
 459         fprintf(stderr, "Usage: %s [nreaders [ perf | stress ] ]\n", argv[0]);
 460         exit(-1);
 461 }
 462
 463 int main(int argc, char *argv[])
 464 {
 465         int nreaders = 1;
 466         int cpustride = 1;
 467
 468         smp_init();
 469         //rcu_init();
 470         srandom(time(NULL));
 471         if (random() & 0x100) {
 472                 fprintf(stderr, "Allocating per-CPU call_rcu threads.\n");
 473                 if (create_all_cpu_call_rcu_data(0))
 474                         perror("create_all_cpu_call_rcu_data");
 475         }
 476
 477 #ifdef DEBUG_YIELD
 478         yield_active |= YIELD_READ;
 479         yield_active |= YIELD_WRITE;
 480 #endif
 481
 482         if (argc > 1) {
 483                 nreaders = strtoul(argv[1], NULL, 0);
 484                 if (argc == 2)
 485                         perftest(nreaders, cpustride);
 486                 if (argc > 3)
 487                         cpustride = strtoul(argv[3], NULL, 0);
 488                 if (strcmp(argv[2], "perf") == 0)
 489                         perftest(nreaders, cpustride);
 490                 else if (strcmp(argv[2], "rperf") == 0)
 491                         rperftest(nreaders, cpustride);
 492                 else if (strcmp(argv[2], "uperf") == 0)
 493                         uperftest(nreaders, cpustride);
 494                 else if (strcmp(argv[2], "stress") == 0)
 495                         stresstest(nreaders);
 496                 usage(argc, argv);
 497         }
 498         perftest(nreaders, cpustride);
 499         return 0;
 500 }