tools/tests/affinity/pool.c

   1 #include <AvailabilityMacros.h>
   2 #include <mach/thread_policy.h>
   3 #include <mach/mach.h>
   4 #include <mach/mach_error.h>
   5 #include <mach/mach_time.h>
   6 #include <pthread.h>
   7 #include <sys/queue.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <string.h>
  11 #include <unistd.h>
  12 #include <err.h>
  13
  14 /*
  15  * Pool is another multithreaded test/benchmarking program to evaluate
  16  * affinity set placement in Leopard.
  17  *
  18  * The basic picture is:
  19  *
  20  *                  -> producer --                 -> consumer --
  21  *       free     /                \    work     /                \
  22  *    -> queue --      ...          --> queue --                   --
  23  *   |            \                /             \                /  |
  24  *   |              -> producer --                 -> consumer --    |
  25  *    ---------------------------------------------------------------
  26  *
  27  *       <---------- "stage" ---------> <---------- "stage" --------->
  28  *
  29  * There are a series of work stages. Each stage has an input and an output
  30  * queue and multiple threads. The first stage is the producer and subsequent
  31  * stages are consumers. By defuaut there are 2 stages. There are N producer
  32  * and M consumer threads. The are B buffers per producer threads circulating
  33  * through the system.
  34  *
  35  * When affinity is enabled, each producer thread is tagged with an affinity tag
  36  * 1 .. N - so each runs on a different L2 cache. When a buffer is queued to
  37  * the work queue it is tagged with this affinity. When a consumer dequeues a
  38  * work item, it sets its affinity to this tag. Hence consumer threads migrate
  39  * to the same affinity set where the data was produced.
  40  *
  41  * Buffer management uses pthread mutex/condition variables. A thread blocks
  42  * when no buffer is available on a queue and it is signaled when a buffer
  43  * is placed on an empty queue. Queues are tailq'a a la <sys/queue.h>.
  44  * The queue management is centralized in a single routine: what queues to
  45  * use as input and output and what function to call for processing is
  46  * data-driven.
  47  */
  48
  49 pthread_mutex_t funnel;
  50 pthread_cond_t  barrier;
  51
  52 uint64_t        timer;
  53 int             threads;
  54 int             threads_ready = 0;
  55
  56 int             iterations = 10000;
  57 boolean_t       affinity = FALSE;
  58 boolean_t       halting = FALSE;
  59 int             verbosity = 1;
  60
  61 typedef struct work {
  62         TAILQ_ENTRY(work)       link;
  63         int                     *data;
  64         int                     isize;
  65         int                     tag;
  66         int                     number;
  67 } work_t;
  68
  69 /*
  70  * A work queue, complete with pthread objects for its management
  71  */
  72 typedef struct work_queue {
  73         pthread_mutex_t         mtx;
  74         pthread_cond_t          cnd;
  75         TAILQ_HEAD(, work)      queue;
  76         unsigned int            waiters;
  77 } work_queue_t;
  78
  79 /* Worker functions take a integer array and size */
  80 typedef void (worker_fn_t)(int *, int);
  81
  82 /* This struct controls the function of a stage */
  83 #define WORKERS_MAX 10
  84 typedef struct {
  85         int                     stagenum;
  86         char                    *name;
  87         worker_fn_t             *fn;
  88         work_queue_t            *input;
  89         work_queue_t            *output;
  90         work_queue_t            bufq;
  91         int                     work_todo;
  92 } stage_info_t;
  93
  94 /* This defines a worker thread */
  95 typedef struct worker_info {
  96         int                     setnum;
  97         stage_info_t            *stage;
  98         pthread_t               thread;
  99 } worker_info_t;
 100
 101 #define DBG(x...) do {                          \
 102         if (verbosity > 1) {                    \
 103                 pthread_mutex_lock(&funnel);    \
 104                 printf(x);                      \
 105                 pthread_mutex_unlock(&funnel);  \
 106         }                                       \
 107 } while (0)
 108
 109 #define mutter(x...) do {                       \
 110         if (verbosity > 0) {                    \
 111                 printf(x);                      \
 112         }                                       \
 113 } while (0)
 114
 115 #define s_if_plural(x)  (((x) > 1) ? "s" : "")
 116
 117 static void
 118 usage()
 119 {
 120         fprintf(stderr,
 121                 "usage: pool [-a]    Turn affinity on (off)\n"
 122                 "            [-b B]  Number of buffers per producer (2)\n"
 123                 "            [-i I]  Number of buffers to produce (10000)\n"
 124                 "            [-s S]  Number of stages (2)\n"
 125                 "            [-p P]  Number of pages per buffer (256=1MB)]\n"
 126                 "            [-w]    Consumer writes data\n"
 127                 "            [-v V]  Verbosity level 0..2 (1)\n"
 128                 "            [N [M]] Number of producer and consumers (2)\n"
 129         );
 130         exit(1);
 131 }
 132
 133 /* Trivial producer: write to each byte */
 134 void
 135 writer_fn(int *data, int isize)
 136 {
 137         int     i;
 138
 139         for (i = 0; i < isize; i++) {
 140                 data[i] = i;
 141         }
 142 }
 143
 144 /* Trivial consumer: read each byte */
 145 void
 146 reader_fn(int *data, int isize)
 147 {
 148         int     i;
 149         int     datum;
 150
 151         for (i = 0; i < isize; i++) {
 152                 datum = data[i];
 153         }
 154 }
 155
 156 /* Consumer reading and writing the buffer */
 157 void
 158 reader_writer_fn(int *data, int isize)
 159 {
 160         int     i;
 161
 162         for (i = 0; i < isize; i++) {
 163                 data[i] += 1;
 164         }
 165 }
 166
 167 void
 168 affinity_set(int tag)
 169 {
 170         kern_return_t                   ret;
 171         thread_affinity_policy_data_t   policy;
 172         if (affinity) {
 173                 policy.affinity_tag = tag;
 174                 ret = thread_policy_set(
 175                                 mach_thread_self(), THREAD_AFFINITY_POLICY,
 176                                 (thread_policy_t) &policy,
 177                                 THREAD_AFFINITY_POLICY_COUNT);
 178                 if (ret != KERN_SUCCESS)
 179                         printf("thread_policy_set(THREAD_AFFINITY_POLICY) returned %d\n", ret);
 180         }
 181 }
 182
 183 /*
 184  * This is the central function for every thread.
 185  * For each invocation, its role is ets by (a pointer to) a stage_info_t.
 186  */
 187 void *
 188 manager_fn(void *arg)
 189 {
 190         worker_info_t   *wp = (worker_info_t *) arg;
 191         stage_info_t    *sp = wp->stage;
 192         boolean_t       is_producer = (sp->stagenum == 0);
 193         long            iteration = 0;
 194         int             current_tag = 0;
 195
 196         kern_return_t                   ret;
 197         thread_extended_policy_data_t   epolicy;
 198         epolicy.timeshare = FALSE;
 199         ret = thread_policy_set(
 200                         mach_thread_self(), THREAD_EXTENDED_POLICY,
 201                         (thread_policy_t) &epolicy,
 202                         THREAD_EXTENDED_POLICY_COUNT);
 203         if (ret != KERN_SUCCESS)
 204                 printf("thread_policy_set(THREAD_EXTENDED_POLICY) returned %d\n", ret);
 205
 206         /*
 207          * If we're using affinity sets and we're a producer
 208          * set our tag to by our thread set number.
 209          */
 210         if (affinity && is_producer) {
 211                 affinity_set(wp->setnum);
 212                 current_tag = wp->setnum;
 213         }
 214
 215         DBG("Starting %s %d, stage: %d\n", sp->name, wp->setnum, sp->stagenum);
 216
 217         /*
 218          * Start barrier.
 219          * The tets thread to get here releases everyone and starts the timer.
 220          */
 221         pthread_mutex_lock(&funnel);
 222         threads_ready++;
 223         if (threads_ready == threads) {
 224                 pthread_mutex_unlock(&funnel);
 225                 if (halting) {
 226                         printf("  all threads ready for process %d, "
 227                                 "hit any key to start", getpid());
 228                         fflush(stdout);
 229                         (void) getchar();
 230                 }
 231                 pthread_cond_broadcast(&barrier);
 232                 timer = mach_absolute_time();
 233         } else {
 234                 pthread_cond_wait(&barrier, &funnel);
 235                 pthread_mutex_unlock(&funnel);
 236         }
 237
 238         do {
 239                 work_t          *workp;
 240
 241                 /*
 242                  * Get a buffer from the input queue.
 243                  * Block if none.
 244                  * Quit if all work done.
 245                  */
 246                 pthread_mutex_lock(&sp->input->mtx);
 247                 while (1) {
 248                         if (sp->work_todo == 0) {
 249                                 pthread_mutex_unlock(&sp->input->mtx);
 250                                 goto out;
 251                         }
 252                         workp = TAILQ_FIRST(&(sp->input->queue));
 253                         if (workp != NULL)
 254                                 break;
 255                         DBG("    %s[%d,%d] todo %d waiting for buffer\n",
 256                                 sp->name, wp->setnum, sp->stagenum, sp->work_todo);
 257                         sp->input->waiters++;
 258                         pthread_cond_wait(&sp->input->cnd, &sp->input->mtx);
 259                         sp->input->waiters--;
 260                 }
 261                 TAILQ_REMOVE(&(sp->input->queue), workp, link);
 262                 iteration = sp->work_todo--;
 263                 pthread_mutex_unlock(&sp->input->mtx);
 264
 265                 if (is_producer) {
 266                         workp->number = iteration;
 267                         workp->tag = wp->setnum;
 268                 } else {
 269                         if (affinity && current_tag != workp->tag) {
 270                                 affinity_set(workp->tag);
 271                                 current_tag = workp->tag;
 272                         }
 273                 }
 274
 275                 DBG("  %s[%d,%d] todo %d work %p data %p\n",
 276                         sp->name, wp->setnum, sp->stagenum, iteration, workp, workp->data);
 277
 278                 /* Do our stuff with the buffer */
 279                 (void) sp->fn(workp->data, workp->isize);
 280
 281                 /*
 282                  * Place the buffer on the input queue of the next stage.
 283                  * Signal waiters if required.
 284                  */
 285                 pthread_mutex_lock(&sp->output->mtx);
 286                 TAILQ_INSERT_TAIL(&(sp->output->queue), workp, link);
 287                 if (sp->output->waiters) {
 288                         DBG("    %s[%d,%d] todo %d signaling work\n",
 289                                 sp->name, wp->setnum, sp->stagenum, iteration);
 290                         pthread_cond_signal(&sp->output->cnd);
 291                 }
 292                 pthread_mutex_unlock(&sp->output->mtx);
 293
 294         } while (1);
 295
 296 out:
 297         pthread_cond_broadcast(&sp->output->cnd);
 298
 299         DBG("Ending %s[%d,%d]\n", sp->name, wp->setnum, sp->stagenum);
 300
 301         return (void *) iteration;
 302 }
 303
 304 void (*producer_fnp)(int *data, int isize) = &writer_fn;
 305 void (*consumer_fnp)(int *data, int isize) = &reader_fn;
 306
 307 int
 308 main(int argc, char *argv[])
 309 {
 310         int                     i;
 311         int                     j;
 312         int                     k;
 313         int                     pages = 256; /* 1MB */
 314         int                     buffers = 2;
 315         int                     producers = 2;
 316         int                     consumers = 2;
 317         int                     stages = 2;
 318         int                     *status;
 319         stage_info_t            *stage_info;
 320         stage_info_t            *sp;
 321         worker_info_t           *worker_info;
 322         worker_info_t           *wp;
 323         kern_return_t           ret;
 324         int                     c;
 325
 326         /* Do switch parsing: */
 327         while ((c = getopt (argc, argv, "ab:i:p:s:twv:")) != -1) {
 328                 switch (c) {
 329                 case 'a':
 330                         affinity = !affinity;
 331                         break;
 332                 case 'b':
 333                         buffers = atoi(optarg);
 334                         break;
 335                 case 'i':
 336                         iterations = atoi(optarg);
 337                         break;
 338                 case 'p':
 339                         pages = atoi(optarg);
 340                         break;
 341                 case 's':
 342                         stages = atoi(optarg);
 343                         if (stages >= WORKERS_MAX)
 344                                 usage();
 345                         break;
 346                 case 't':
 347                         halting = TRUE;
 348                         break;
 349                 case 'w':
 350                         consumer_fnp = &reader_writer_fn;
 351                         break;
 352                 case 'v':
 353                         verbosity = atoi(optarg);
 354                         break;
 355                 case 'h':
 356                 case '?':
 357                 default:
 358                         usage();
 359                 }
 360         }
 361         argc -= optind; argv += optind;
 362         if (argc > 0)
 363                 producers = atoi(*argv);
 364         argc--; argv++;
 365         if (argc > 0)
 366                 consumers = atoi(*argv);
 367
 368         pthread_mutex_init(&funnel, NULL);
 369         pthread_cond_init(&barrier, NULL);
 370
 371         /*
 372          * Fire up the worker threads.
 373          */
 374         threads = consumers * (stages - 1) + producers;
 375         mutter("Launching %d producer%s with %d stage%s of %d consumer%s\n"
 376                 "  with %saffinity, consumer reads%s data\n",
 377                 producers, s_if_plural(producers),
 378                 stages - 1, s_if_plural(stages - 1),
 379                 consumers, s_if_plural(consumers),
 380                 affinity? "": "no ",
 381                 (consumer_fnp == &reader_writer_fn)? " and writes" : "");
 382         if (pages < 256)
 383                 mutter("  %dkB bytes per buffer, ", pages * 4);
 384         else
 385                 mutter("  %dMB bytes per buffer, ", pages / 256);
 386         mutter("%d buffer%s per producer ",
 387                 buffers, s_if_plural(buffers));
 388         if (buffers * pages < 256)
 389                 mutter("(total %dkB)\n", buffers * pages * 4);
 390         else
 391                 mutter("(total %dMB)\n", buffers * pages / 256);
 392         mutter("  processing %d buffer%s...\n",
 393                 iterations, s_if_plural(iterations));
 394
 395         stage_info = (stage_info_t *) malloc(stages * sizeof(stage_info_t));
 396         worker_info = (worker_info_t *) malloc(threads * sizeof(worker_info_t));
 397
 398         /* Set up the queue for the workers of this thread set: */
 399         for (i = 0; i < stages; i++) {
 400                 sp = &stage_info[i];
 401                 sp->stagenum = i;
 402                 pthread_mutex_init(&sp->bufq.mtx, NULL);
 403                 pthread_cond_init(&sp->bufq.cnd, NULL);
 404                 TAILQ_INIT(&sp->bufq.queue);
 405                 sp->bufq.waiters = 0;
 406                 if (i == 0) {
 407                         sp->fn = producer_fnp;
 408                         sp->name = "producer";
 409                 } else {
 410                         sp->fn = consumer_fnp;
 411                         sp->name = "consumer";
 412                 }
 413                 sp->input = &sp->bufq;
 414                 sp->output = &stage_info[(i + 1) % stages].bufq;
 415                 stage_info[i].work_todo = iterations;
 416         }
 417
 418         /* Create the producers */
 419         for (i = 0; i < producers; i++) {
 420                 work_t  *work_array;
 421                 int     *data;
 422                 int     isize;
 423
 424                 isize = pages * 4096 / sizeof(int);
 425                 data = (int *) malloc(buffers * pages * 4096);
 426
 427                 /* Set up the empty work buffers */
 428                 work_array = (work_t *)  malloc(buffers * sizeof(work_t));
 429                 for (j = 0; j < buffers; j++) {
 430                         work_array[j].data = data + (isize * j);
 431                         work_array[j].isize = isize;
 432                         work_array[j].tag = 0;
 433                         TAILQ_INSERT_TAIL(&stage_info[0].bufq.queue, &work_array[j], link);
 434                         DBG("  empty work item %p for data %p\n",
 435                                 &work_array[j], work_array[j].data);
 436                 }
 437                 wp = &worker_info[i];
 438                 wp->setnum = i + 1;
 439                 wp->stage = &stage_info[0];
 440                 if (ret = pthread_create(&wp->thread,
 441                                          NULL,
 442                                          &manager_fn,
 443                                          (void *) wp))
 444                         err(1, "pthread_create %d,%d", 0, i);
 445         }
 446
 447         /* Create consumers */
 448         for (i = 1; i < stages; i++) {
 449                 for (j = 0; j < consumers; j++) {
 450                         wp = &worker_info[producers + (consumers*(i-1)) + j];
 451                         wp->setnum = j + 1;
 452                         wp->stage = &stage_info[i];
 453                         if (ret = pthread_create(&wp->thread,
 454                                                 NULL,
 455                                                 &manager_fn,
 456                                                 (void *) wp))
 457                                 err(1, "pthread_create %d,%d", i, j);
 458                 }
 459         }
 460
 461         /*
 462          * We sit back anf wait for the slaves to finish.
 463          */
 464         for (k = 0; k < threads; k++) {
 465                 int     i;
 466                 int     j;
 467
 468                 wp = &worker_info[k];
 469                 if (k < producers) {
 470                         i = 0;
 471                         j = k;
 472                 } else {
 473                         i = (k - producers) / consumers;
 474                         j = (k - producers) % consumers;
 475                 }
 476                 if(ret = pthread_join(wp->thread, (void **)&status))
 477                     err(1, "pthread_join %d,%d", i, j);
 478                 DBG("Thread %d,%d status %d\n", i, j, status);
 479         }
 480
 481         /*
 482          * See how long the work took.
 483          */
 484         timer = mach_absolute_time() - timer;
 485         timer = timer / 1000000ULL;
 486         printf("%d.%03d seconds elapsed.\n",
 487                 (int) (timer/1000ULL), (int) (timer % 1000ULL));
 488
 489         return 0;
 490 }