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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 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 volatile int goflag __attribute__((__aligned__(CAA_CACHE_LINE_SIZE)))
  83         = GOFLAG_INIT;
  84
  85 #define RCU_READ_RUN 1000
  86
  87 //MD
  88 #define RCU_READ_NESTABLE
  89
  90 #ifdef RCU_READ_NESTABLE
  91 #define rcu_read_lock_nest() rcu_read_lock()
  92 #define rcu_read_unlock_nest() rcu_read_unlock()
  93 #else /* #ifdef RCU_READ_NESTABLE */
  94 #define rcu_read_lock_nest()
  95 #define rcu_read_unlock_nest()
  96 #endif /* #else #ifdef RCU_READ_NESTABLE */
  97
  98 #ifdef TORTURE_QSBR
  99 #define mark_rcu_quiescent_state        rcu_quiescent_state
 100 #define put_thread_offline              rcu_thread_offline
 101 #define put_thread_online               rcu_thread_online
 102 #endif
 103
 104 #ifndef mark_rcu_quiescent_state
 105 #define mark_rcu_quiescent_state() do ; while (0)
 106 #endif /* #ifdef mark_rcu_quiescent_state */
 107
 108 #ifndef put_thread_offline
 109 #define put_thread_offline()            do ; while (0)
 110 #define put_thread_online()             do ; while (0)
 111 #define put_thread_online_delay()       do ; while (0)
 112 #else /* #ifndef put_thread_offline */
 113 #define put_thread_online_delay()       synchronize_rcu()
 114 #endif /* #else #ifndef put_thread_offline */
 115
 116 /*
 117  * Performance test.
 118  */
 119
 120 void *rcu_read_perf_test(void *arg)
 121 {
 122         struct call_rcu_data *crdp;
 123         int i;
 124         int me = (long)arg;
 125         long long n_reads_local = 0;
 126
 127         rcu_register_thread();
 128         run_on(me);
 129         uatomic_inc(&nthreadsrunning);
 130         put_thread_offline();
 131         while (goflag == GOFLAG_INIT)
 132                 poll(NULL, 0, 1);
 133         put_thread_online();
 134         while (goflag == GOFLAG_RUN) {
 135                 for (i = 0; i < RCU_READ_RUN; i++) {
 136                         rcu_read_lock();
 137                         /* rcu_read_lock_nest(); */
 138                         /* rcu_read_unlock_nest(); */
 139                         rcu_read_unlock();
 140                 }
 141                 n_reads_local += RCU_READ_RUN;
 142                 mark_rcu_quiescent_state();
 143         }
 144         __get_thread_var(n_reads_pt) += n_reads_local;
 145         put_thread_offline();
 146         crdp = get_thread_call_rcu_data();
 147         set_thread_call_rcu_data(NULL);
 148         call_rcu_data_free(crdp);
 149         rcu_unregister_thread();
 150
 151         return (NULL);
 152 }
 153
 154 void *rcu_update_perf_test(void *arg)
 155 {
 156         long long n_updates_local = 0;
 157
 158         if ((random() & 0xf00) == 0) {
 159                 struct call_rcu_data *crdp;
 160
 161                 crdp = create_call_rcu_data(0, -1);
 162                 if (crdp != NULL) {
 163                         fprintf(stderr,
 164                                 "Using per-thread call_rcu() worker.\n");
 165                         set_thread_call_rcu_data(crdp);
 166                 }
 167         }
 168         uatomic_inc(&nthreadsrunning);
 169         while (goflag == GOFLAG_INIT)
 170                 poll(NULL, 0, 1);
 171         while (goflag == GOFLAG_RUN) {
 172                 synchronize_rcu();
 173                 n_updates_local++;
 174         }
 175         __get_thread_var(n_updates_pt) += n_updates_local;
 176         return NULL;
 177 }
 178
 179 void perftestinit(void)
 180 {
 181         init_per_thread(n_reads_pt, 0LL);
 182         init_per_thread(n_updates_pt, 0LL);
 183         uatomic_set(&nthreadsrunning, 0);
 184 }
 185
 186 void perftestrun(int nthreads, int nreaders, int nupdaters)
 187 {
 188         int t;
 189         int duration = 1;
 190
 191         cmm_smp_mb();
 192         while (uatomic_read(&nthreadsrunning) < nthreads)
 193                 poll(NULL, 0, 1);
 194         goflag = GOFLAG_RUN;
 195         cmm_smp_mb();
 196         sleep(duration);
 197         cmm_smp_mb();
 198         goflag = GOFLAG_STOP;
 199         cmm_smp_mb();
 200         wait_all_threads();
 201         for_each_thread(t) {
 202                 n_reads += per_thread(n_reads_pt, t);
 203                 n_updates += per_thread(n_updates_pt, t);
 204         }
 205         printf("n_reads: %lld  n_updates: %ld  nreaders: %d  nupdaters: %d duration: %d\n",
 206                n_reads, n_updates, nreaders, nupdaters, duration);
 207         printf("ns/read: %g  ns/update: %g\n",
 208                ((duration * 1000*1000*1000.*(double)nreaders) /
 209                 (double)n_reads),
 210                ((duration * 1000*1000*1000.*(double)nupdaters) /
 211                 (double)n_updates));
 212         if (get_cpu_call_rcu_data(0)) {
 213                 fprintf(stderr, "Deallocating per-CPU call_rcu threads.\n");
 214                 free_all_cpu_call_rcu_data();
 215         }
 216         exit(0);
 217 }
 218
 219 void perftest(int nreaders, int cpustride)
 220 {
 221         int i;
 222         long arg;
 223
 224         perftestinit();
 225         for (i = 0; i < nreaders; i++) {
 226                 arg = (long)(i * cpustride);
 227                 create_thread(rcu_read_perf_test, (void *)arg);
 228         }
 229         arg = (long)(i * cpustride);
 230         create_thread(rcu_update_perf_test, (void *)arg);
 231         perftestrun(i + 1, nreaders, 1);
 232 }
 233
 234 void rperftest(int nreaders, int cpustride)
 235 {
 236         int i;
 237         long arg;
 238
 239         perftestinit();
 240         init_per_thread(n_reads_pt, 0LL);
 241         for (i = 0; i < nreaders; i++) {
 242                 arg = (long)(i * cpustride);
 243                 create_thread(rcu_read_perf_test, (void *)arg);
 244         }
 245         perftestrun(i, nreaders, 0);
 246 }
 247
 248 void uperftest(int nupdaters, int cpustride)
 249 {
 250         int i;
 251         long arg;
 252
 253         perftestinit();
 254         init_per_thread(n_reads_pt, 0LL);
 255         for (i = 0; i < nupdaters; i++) {
 256                 arg = (long)(i * cpustride);
 257                 create_thread(rcu_update_perf_test, (void *)arg);
 258         }
 259         perftestrun(i, 0, nupdaters);
 260 }
 261
 262 /*
 263  * Stress test.
 264  */
 265
 266 #define RCU_STRESS_PIPE_LEN 10
 267
 268 struct rcu_stress {
 269         int pipe_count;
 270         int mbtest;
 271 };
 272
 273 struct rcu_stress rcu_stress_array[RCU_STRESS_PIPE_LEN] = { { 0 } };
 274 struct rcu_stress *rcu_stress_current;
 275 int rcu_stress_idx = 0;
 276
 277 int n_mberror = 0;
 278 DEFINE_PER_THREAD(long long [RCU_STRESS_PIPE_LEN + 1], rcu_stress_count);
 279
 280 int garbage = 0;
 281
 282 void *rcu_read_stress_test(void *arg)
 283 {
 284         int i;
 285         int itercnt = 0;
 286         struct rcu_stress *p;
 287         int pc;
 288
 289         rcu_register_thread();
 290         put_thread_offline();
 291         while (goflag == GOFLAG_INIT)
 292                 poll(NULL, 0, 1);
 293         put_thread_online();
 294         while (goflag == GOFLAG_RUN) {
 295                 rcu_read_lock();
 296                 p = rcu_dereference(rcu_stress_current);
 297                 if (p->mbtest == 0)
 298                         n_mberror++;
 299                 rcu_read_lock_nest();
 300                 for (i = 0; i < 100; i++)
 301                         garbage++;
 302                 rcu_read_unlock_nest();
 303                 pc = p->pipe_count;
 304                 rcu_read_unlock();
 305                 if ((pc > RCU_STRESS_PIPE_LEN) || (pc < 0))
 306                         pc = RCU_STRESS_PIPE_LEN;
 307                 __get_thread_var(rcu_stress_count)[pc]++;
 308                 __get_thread_var(n_reads_pt)++;
 309                 mark_rcu_quiescent_state();
 310                 if ((++itercnt % 0x1000) == 0) {
 311                         put_thread_offline();
 312                         put_thread_online_delay();
 313                         put_thread_online();
 314                 }
 315         }
 316         put_thread_offline();
 317         rcu_unregister_thread();
 318
 319         return (NULL);
 320 }
 321
 322 static pthread_mutex_t call_rcu_test_mutex = PTHREAD_MUTEX_INITIALIZER;
 323 static pthread_cond_t call_rcu_test_cond = PTHREAD_COND_INITIALIZER;
 324
 325 void rcu_update_stress_test_rcu(struct rcu_head *head)
 326 {
 327         if (pthread_mutex_lock(&call_rcu_test_mutex) != 0) {
 328                 perror("pthread_mutex_lock");
 329                 exit(-1);
 330         }
 331         if (pthread_cond_signal(&call_rcu_test_cond) != 0) {
 332                 perror("pthread_cond_signal");
 333                 exit(-1);
 334         }
 335         if (pthread_mutex_unlock(&call_rcu_test_mutex) != 0) {
 336                 perror("pthread_mutex_unlock");
 337                 exit(-1);
 338         }
 339 }
 340
 341 void *rcu_update_stress_test(void *arg)
 342 {
 343         int i;
 344         struct rcu_stress *p;
 345         struct rcu_head rh;
 346
 347         while (goflag == GOFLAG_INIT)
 348                 poll(NULL, 0, 1);
 349         while (goflag == GOFLAG_RUN) {
 350                 i = rcu_stress_idx + 1;
 351                 if (i >= RCU_STRESS_PIPE_LEN)
 352                         i = 0;
 353                 p = &rcu_stress_array[i];
 354                 p->mbtest = 0;
 355                 cmm_smp_mb();
 356                 p->pipe_count = 0;
 357                 p->mbtest = 1;
 358                 rcu_assign_pointer(rcu_stress_current, p);
 359                 rcu_stress_idx = i;
 360                 for (i = 0; i < RCU_STRESS_PIPE_LEN; i++)
 361                         if (i != rcu_stress_idx)
 362                                 rcu_stress_array[i].pipe_count++;
 363                 if (n_updates & 0x1)
 364                         synchronize_rcu();
 365                 else {
 366                         if (pthread_mutex_lock(&call_rcu_test_mutex) != 0) {
 367                                 perror("pthread_mutex_lock");
 368                                 exit(-1);
 369                         }
 370                         call_rcu(&rh, rcu_update_stress_test_rcu);
 371                         if (pthread_cond_wait(&call_rcu_test_cond,
 372                                               &call_rcu_test_mutex) != 0) {
 373                                 perror("pthread_cond_wait");
 374                                 exit(-1);
 375                         }
 376                         if (pthread_mutex_unlock(&call_rcu_test_mutex) != 0) {
 377                                 perror("pthread_mutex_unlock");
 378                                 exit(-1);
 379                         }
 380                 }
 381                 n_updates++;
 382         }
 383         return NULL;
 384 }
 385
 386 void *rcu_fake_update_stress_test(void *arg)
 387 {
 388         if ((random() & 0xf00) == 0) {
 389                 struct call_rcu_data *crdp;
 390
 391                 crdp = create_call_rcu_data(0, -1);
 392                 if (crdp != NULL) {
 393                         fprintf(stderr,
 394                                 "Using per-thread call_rcu() worker.\n");
 395                         set_thread_call_rcu_data(crdp);
 396                 }
 397         }
 398         while (goflag == GOFLAG_INIT)
 399                 poll(NULL, 0, 1);
 400         while (goflag == GOFLAG_RUN) {
 401                 synchronize_rcu();
 402                 poll(NULL, 0, 1);
 403         }
 404         return NULL;
 405 }
 406
 407 void stresstest(int nreaders)
 408 {
 409         int i;
 410         int t;
 411         long long *p;
 412         long long sum;
 413
 414         init_per_thread(n_reads_pt, 0LL);
 415         for_each_thread(t) {
 416                 p = &per_thread(rcu_stress_count,t)[0];
 417                 for (i = 0; i <= RCU_STRESS_PIPE_LEN; i++)
 418                         p[i] = 0LL;
 419         }
 420         rcu_stress_current = &rcu_stress_array[0];
 421         rcu_stress_current->pipe_count = 0;
 422         rcu_stress_current->mbtest = 1;
 423         for (i = 0; i < nreaders; i++)
 424                 create_thread(rcu_read_stress_test, NULL);
 425         create_thread(rcu_update_stress_test, NULL);
 426         for (i = 0; i < 5; i++)
 427                 create_thread(rcu_fake_update_stress_test, NULL);
 428         cmm_smp_mb();
 429         goflag = GOFLAG_RUN;
 430         cmm_smp_mb();
 431         sleep(10);
 432         cmm_smp_mb();
 433         goflag = GOFLAG_STOP;
 434         cmm_smp_mb();
 435         wait_all_threads();
 436         for_each_thread(t)
 437                 n_reads += per_thread(n_reads_pt, t);
 438         printf("n_reads: %lld  n_updates: %ld  n_mberror: %d\n",
 439                n_reads, n_updates, n_mberror);
 440         printf("rcu_stress_count:");
 441         for (i = 0; i <= RCU_STRESS_PIPE_LEN; i++) {
 442                 sum = 0LL;
 443                 for_each_thread(t) {
 444                         sum += per_thread(rcu_stress_count, t)[i];
 445                 }
 446                 printf(" %lld", sum);
 447         }
 448         printf("\n");
 449         if (get_cpu_call_rcu_data(0)) {
 450                 fprintf(stderr, "Deallocating per-CPU call_rcu threads.\n");
 451                 free_all_cpu_call_rcu_data();
 452         }
 453         exit(0);
 454 }
 455
 456 /*
 457  * Mainprogram.
 458  */
 459
 460 void usage(int argc, char *argv[])
 461 {
 462         fprintf(stderr, "Usage: %s [nreaders [ perf | stress ] ]\n", argv[0]);
 463         exit(-1);
 464 }
 465
 466 int main(int argc, char *argv[])
 467 {
 468         int nreaders = 1;
 469         int cpustride = 1;
 470
 471         smp_init();
 472         //rcu_init();
 473         srandom(time(NULL));
 474         if (random() & 0x100) {
 475                 fprintf(stderr, "Allocating per-CPU call_rcu threads.\n");
 476                 if (create_all_cpu_call_rcu_data(0))
 477                         perror("create_all_cpu_call_rcu_data");
 478         }
 479
 480 #ifdef DEBUG_YIELD
 481         yield_active |= YIELD_READ;
 482         yield_active |= YIELD_WRITE;
 483 #endif
 484
 485         if (argc > 1) {
 486                 nreaders = strtoul(argv[1], NULL, 0);
 487                 if (argc == 2)
 488                         perftest(nreaders, cpustride);
 489                 if (argc > 3)
 490                         cpustride = strtoul(argv[3], NULL, 0);
 491                 if (strcmp(argv[2], "perf") == 0)
 492                         perftest(nreaders, cpustride);
 493                 else if (strcmp(argv[2], "rperf") == 0)
 494                         rperftest(nreaders, cpustride);
 495                 else if (strcmp(argv[2], "uperf") == 0)
 496                         uperftest(nreaders, cpustride);
 497                 else if (strcmp(argv[2], "stress") == 0)
 498                         stresstest(nreaders);
 499                 usage(argc, argv);
 500         }
 501         perftest(nreaders, cpustride);
 502         return 0;
 503 }