mono/metadata/threadpool.c

   1 /*
   2  * threadpool.c: Microsoft threadpool runtime support
   3  *
   4  * Author:
   5  *      Ludovic Henry (ludovic.henry@xamarin.com)
   6  *
   7  * Copyright 2015 Xamarin, Inc (http://www.xamarin.com)
   8  * Licensed under the MIT license. See LICENSE file in the project root for full license information.
   9  */
  10
  11 //
  12 // Copyright (c) Microsoft. All rights reserved.
  13 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
  14 //
  15 // Files:
  16 //  - src/vm/comthreadpool.cpp
  17 //  - src/vm/win32threadpoolcpp
  18 //  - src/vm/threadpoolrequest.cpp
  19 //  - src/vm/hillclimbing.cpp
  20 //
  21 // Ported from C++ to C and adjusted to Mono runtime
  22
  23 #include <stdlib.h>
  24 #define _USE_MATH_DEFINES // needed by MSVC to define math constants
  25 #include <math.h>
  26 #include <config.h>
  27 #include <glib.h>
  28
  29 #include <mono/metadata/class-internals.h>
  30 #include <mono/metadata/exception.h>
  31 #include <mono/metadata/gc-internals.h>
  32 #include <mono/metadata/object.h>
  33 #include <mono/metadata/object-internals.h>
  34 #include <mono/metadata/threadpool.h>
  35 #include <mono/metadata/threadpool-worker.h>
  36 #include <mono/metadata/threadpool-io.h>
  37 #include <mono/metadata/w32event.h>
  38 #include <mono/utils/atomic.h>
  39 #include <mono/utils/mono-compiler.h>
  40 #include <mono/utils/mono-complex.h>
  41 #include <mono/utils/mono-lazy-init.h>
  42 #include <mono/utils/mono-logger.h>
  43 #include <mono/utils/mono-logger-internals.h>
  44 #include <mono/utils/mono-proclib.h>
  45 #include <mono/utils/mono-threads.h>
  46 #include <mono/utils/mono-time.h>
  47 #include <mono/utils/refcount.h>
  48
  49 typedef struct {
  50         MonoDomain *domain;
  51         /* Number of outstanding jobs */
  52         gint32 outstanding_request;
  53         /* Number of currently executing jobs */
  54         gint32 threadpool_jobs;
  55         /* Signalled when threadpool_jobs + outstanding_request is 0 */
  56         /* Protected by threadpool->domains_lock */
  57         MonoCoopCond cleanup_cond;
  58 } ThreadPoolDomain;
  59
  60 typedef union {
  61         struct {
  62                 gint16 starting; /* starting, but not yet in worker_callback */
  63                 gint16 working; /* executing worker_callback */
  64         } _;
  65         gint32 as_gint32;
  66 } ThreadPoolCounter;
  67
  68 typedef struct {
  69         MonoRefCount ref;
  70
  71         GPtrArray *domains; // ThreadPoolDomain* []
  72         MonoCoopMutex domains_lock;
  73
  74         GPtrArray *threads; // MonoInternalThread* []
  75         MonoCoopMutex threads_lock;
  76         MonoCoopCond threads_exit_cond;
  77
  78         ThreadPoolCounter counters;
  79
  80         gint32 limit_io_min;
  81         gint32 limit_io_max;
  82
  83         MonoThreadPoolWorker *worker;
  84 } ThreadPool;
  85
  86 static mono_lazy_init_t status = MONO_LAZY_INIT_STATUS_NOT_INITIALIZED;
  87
  88 static ThreadPool* threadpool;
  89
  90 #define COUNTER_ATOMIC(threadpool,var,block) \
  91         do { \
  92                 ThreadPoolCounter __old; \
  93                 do { \
  94                         g_assert (threadpool); \
  95                         (var) = __old = COUNTER_READ (threadpool); \
  96                         { block; } \
  97                         if (!(counter._.starting >= 0)) \
  98                                 g_error ("%s: counter._.starting = %d, but should be >= 0", __func__, counter._.starting); \
  99                         if (!(counter._.working >= 0)) \
 100                                 g_error ("%s: counter._.working = %d, but should be >= 0", __func__, counter._.working); \
 101                 } while (InterlockedCompareExchange (&threadpool->counters.as_gint32, (var).as_gint32, __old.as_gint32) != __old.as_gint32); \
 102         } while (0)
 103
 104 static inline ThreadPoolCounter
 105 COUNTER_READ (ThreadPool *threadpool)
 106 {
 107         ThreadPoolCounter counter;
 108         counter.as_gint32 = InterlockedRead (&threadpool->counters.as_gint32);
 109         return counter;
 110 }
 111
 112 static inline void
 113 domains_lock (void)
 114 {
 115         mono_coop_mutex_lock (&threadpool->domains_lock);
 116 }
 117
 118 static inline void
 119 domains_unlock (void)
 120 {
 121         mono_coop_mutex_unlock (&threadpool->domains_lock);
 122 }
 123
 124 static void
 125 destroy (gpointer unused)
 126 {
 127         g_ptr_array_free (threadpool->domains, TRUE);
 128         mono_coop_mutex_destroy (&threadpool->domains_lock);
 129
 130         g_ptr_array_free (threadpool->threads, TRUE);
 131         mono_coop_mutex_destroy (&threadpool->threads_lock);
 132         mono_coop_cond_destroy (&threadpool->threads_exit_cond);
 133
 134         /* We cannot free the threadpool, because there is a race
 135          * on shutdown where a managed thread may request a new
 136          * threadpool thread, but we already destroyed the
 137          * threadpool. So to avoid a use-after-free, we simply do
 138          * not free the threadpool, as we won't be able to access
 139          * the threadpool anyway because the ref count will be 0 */
 140         // g_free (threadpool);
 141 }
 142
 143 static void
 144 initialize (void)
 145 {
 146         g_assert (!threadpool);
 147         threadpool = g_new0 (ThreadPool, 1);
 148         g_assert (threadpool);
 149
 150         g_assert (sizeof (ThreadPoolCounter) == sizeof (gint32));
 151
 152         mono_refcount_init (threadpool, destroy);
 153
 154         threadpool->domains = g_ptr_array_new ();
 155         mono_coop_mutex_init (&threadpool->domains_lock);
 156
 157         threadpool->threads = g_ptr_array_new ();
 158         mono_coop_mutex_init (&threadpool->threads_lock);
 159         mono_coop_cond_init (&threadpool->threads_exit_cond);
 160
 161         threadpool->limit_io_min = mono_cpu_count ();
 162         threadpool->limit_io_max = CLAMP (threadpool->limit_io_min * 100, MIN (threadpool->limit_io_min, 200), MAX (threadpool->limit_io_min, 200));
 163
 164         mono_threadpool_worker_init (&threadpool->worker);
 165 }
 166
 167 static void
 168 cleanup (void)
 169 {
 170         guint i;
 171         MonoInternalThread *current;
 172
 173         /* we make the assumption along the code that we are
 174          * cleaning up only if the runtime is shutting down */
 175         g_assert (mono_runtime_is_shutting_down ());
 176
 177         current = mono_thread_internal_current ();
 178
 179         mono_coop_mutex_lock (&threadpool->threads_lock);
 180
 181         /* stop all threadpool->threads */
 182         for (i = 0; i < threadpool->threads->len; ++i) {
 183                 MonoInternalThread *thread = (MonoInternalThread*) g_ptr_array_index (threadpool->threads, i);
 184                 if (thread != current)
 185                         mono_thread_internal_abort (thread);
 186         }
 187
 188         mono_coop_mutex_unlock (&threadpool->threads_lock);
 189
 190 #if 0
 191         /* give a chance to the other threads to exit */
 192         mono_thread_info_yield ();
 193
 194         mono_coop_mutex_lock (&threadpool->threads_lock);
 195
 196         for (;;) {
 197                 if (threadpool->threads->len == 0)
 198                         break;
 199
 200                 if (threadpool->threads->len == 1 && g_ptr_array_index (threadpool->threads, 0) == current) {
 201                         /* We are waiting on ourselves */
 202                         break;
 203                 }
 204
 205                 mono_coop_cond_wait (&threadpool->threads_exit_cond, &threadpool->threads_lock);
 206         }
 207
 208         mono_coop_mutex_unlock (&threadpool->threads_lock);
 209 #endif
 210
 211         mono_threadpool_worker_cleanup (threadpool->worker);
 212
 213         mono_refcount_dec (threadpool);
 214 }
 215
 216 gboolean
 217 mono_threadpool_enqueue_work_item (MonoDomain *domain, MonoObject *work_item, MonoError *error)
 218 {
 219         static MonoClass *threadpool_class = NULL;
 220         static MonoMethod *unsafe_queue_custom_work_item_method = NULL;
 221         MonoDomain *current_domain;
 222         MonoBoolean f;
 223         gpointer args [2];
 224
 225         mono_error_init (error);
 226         g_assert (work_item);
 227
 228         if (!threadpool_class)
 229                 threadpool_class = mono_class_load_from_name (mono_defaults.corlib, "System.Threading", "ThreadPool");
 230
 231         if (!unsafe_queue_custom_work_item_method)
 232                 unsafe_queue_custom_work_item_method = mono_class_get_method_from_name (threadpool_class, "UnsafeQueueCustomWorkItem", 2);
 233         g_assert (unsafe_queue_custom_work_item_method);
 234
 235         f = FALSE;
 236
 237         args [0] = (gpointer) work_item;
 238         args [1] = (gpointer) &f;
 239
 240         current_domain = mono_domain_get ();
 241         if (current_domain == domain) {
 242                 mono_runtime_invoke_checked (unsafe_queue_custom_work_item_method, NULL, args, error);
 243                 return_val_if_nok (error, FALSE);
 244         } else {
 245                 mono_thread_push_appdomain_ref (domain);
 246                 if (mono_domain_set (domain, FALSE)) {
 247                         mono_runtime_invoke_checked (unsafe_queue_custom_work_item_method, NULL, args, error);
 248                         if (!is_ok (error)) {
 249                                 mono_thread_pop_appdomain_ref ();
 250                                 return FALSE;
 251                         }
 252                         mono_domain_set (current_domain, TRUE);
 253                 }
 254                 mono_thread_pop_appdomain_ref ();
 255         }
 256         return TRUE;
 257 }
 258
 259 /* LOCKING: domains_lock must be held */
 260 static void
 261 tpdomain_add (ThreadPoolDomain *tpdomain)
 262 {
 263         guint i, len;
 264
 265         g_assert (tpdomain);
 266
 267         len = threadpool->domains->len;
 268         for (i = 0; i < len; ++i) {
 269                 if (g_ptr_array_index (threadpool->domains, i) == tpdomain)
 270                         break;
 271         }
 272
 273         if (i == len)
 274                 g_ptr_array_add (threadpool->domains, tpdomain);
 275 }
 276
 277 /* LOCKING: domains_lock must be held. */
 278 static gboolean
 279 tpdomain_remove (ThreadPoolDomain *tpdomain)
 280 {
 281         g_assert (tpdomain);
 282         return g_ptr_array_remove (threadpool->domains, tpdomain);
 283 }
 284
 285 /* LOCKING: domains_lock must be held */
 286 static ThreadPoolDomain *
 287 tpdomain_get (MonoDomain *domain, gboolean create)
 288 {
 289         guint i;
 290         ThreadPoolDomain *tpdomain;
 291
 292         g_assert (domain);
 293
 294         for (i = 0; i < threadpool->domains->len; ++i) {
 295                 ThreadPoolDomain *tpdomain;
 296
 297                 tpdomain = (ThreadPoolDomain *)g_ptr_array_index (threadpool->domains, i);
 298                 if (tpdomain->domain == domain)
 299                         return tpdomain;
 300         }
 301
 302         if (!create)
 303                 return NULL;
 304
 305         tpdomain = g_new0 (ThreadPoolDomain, 1);
 306         tpdomain->domain = domain;
 307         mono_coop_cond_init (&tpdomain->cleanup_cond);
 308
 309         tpdomain_add (tpdomain);
 310
 311         return tpdomain;
 312 }
 313
 314 static void
 315 tpdomain_free (ThreadPoolDomain *tpdomain)
 316 {
 317         g_free (tpdomain);
 318 }
 319
 320 /* LOCKING: domains_lock must be held */
 321 static ThreadPoolDomain *
 322 tpdomain_get_next (ThreadPoolDomain *current)
 323 {
 324         ThreadPoolDomain *tpdomain = NULL;
 325         guint len;
 326
 327         len = threadpool->domains->len;
 328         if (len > 0) {
 329                 guint i, current_idx = -1;
 330                 if (current) {
 331                         for (i = 0; i < len; ++i) {
 332                                 if (current == g_ptr_array_index (threadpool->domains, i)) {
 333                                         current_idx = i;
 334                                         break;
 335                                 }
 336                         }
 337                         g_assert (current_idx != (guint)-1);
 338                 }
 339                 for (i = current_idx + 1; i < len + current_idx + 1; ++i) {
 340                         ThreadPoolDomain *tmp = (ThreadPoolDomain *)g_ptr_array_index (threadpool->domains, i % len);
 341                         if (tmp->outstanding_request > 0) {
 342                                 tpdomain = tmp;
 343                                 break;
 344                         }
 345                 }
 346         }
 347
 348         return tpdomain;
 349 }
 350
 351 static MonoObject*
 352 try_invoke_perform_wait_callback (MonoObject** exc, MonoError *error)
 353 {
 354         HANDLE_FUNCTION_ENTER ();
 355         mono_error_init (error);
 356         MonoObject *res = mono_runtime_try_invoke (mono_defaults.threadpool_perform_wait_callback_method, NULL, NULL, exc, error);
 357         HANDLE_FUNCTION_RETURN_VAL (res);
 358 }
 359
 360 static void
 361 worker_callback (gpointer unused)
 362 {
 363         MonoError error;
 364         ThreadPoolDomain *tpdomain, *previous_tpdomain;
 365         ThreadPoolCounter counter;
 366         MonoInternalThread *thread;
 367
 368         thread = mono_thread_internal_current ();
 369
 370         COUNTER_ATOMIC (threadpool, counter, {
 371                 if (!(counter._.working < 32767 /* G_MAXINT16 */))
 372                         g_error ("%s: counter._.working = %d, but should be < 32767", __func__, counter._.working);
 373
 374                 counter._.starting --;
 375                 counter._.working ++;
 376         });
 377
 378         if (mono_runtime_is_shutting_down ()) {
 379                 COUNTER_ATOMIC (threadpool, counter, {
 380                         counter._.working --;
 381                 });
 382
 383                 mono_refcount_dec (threadpool);
 384                 return;
 385         }
 386
 387         mono_coop_mutex_lock (&threadpool->threads_lock);
 388         g_ptr_array_add (threadpool->threads, thread);
 389         mono_coop_mutex_unlock (&threadpool->threads_lock);
 390
 391         /*
 392          * This is needed so there is always an lmf frame in the runtime invoke call below,
 393          * so ThreadAbortExceptions are caught even if the thread is in native code.
 394          */
 395         mono_defaults.threadpool_perform_wait_callback_method->save_lmf = TRUE;
 396
 397         domains_lock ();
 398
 399         previous_tpdomain = NULL;
 400
 401         while (!mono_runtime_is_shutting_down ()) {
 402                 gboolean retire = FALSE;
 403
 404                 if ((thread->state & (ThreadState_AbortRequested | ThreadState_SuspendRequested)) != 0) {
 405                         domains_unlock ();
 406                         mono_thread_interruption_checkpoint ();
 407                         domains_lock ();
 408                 }
 409
 410                 tpdomain = tpdomain_get_next (previous_tpdomain);
 411                 if (!tpdomain)
 412                         break;
 413
 414                 tpdomain->outstanding_request --;
 415                 g_assert (tpdomain->outstanding_request >= 0);
 416
 417                 mono_trace (G_LOG_LEVEL_DEBUG, MONO_TRACE_THREADPOOL, "[%p] worker running in domain %p (outstanding requests %d)",
 418                         mono_native_thread_id_get (), tpdomain->domain, tpdomain->outstanding_request);
 419
 420                 g_assert (tpdomain->threadpool_jobs >= 0);
 421                 tpdomain->threadpool_jobs ++;
 422
 423                 domains_unlock ();
 424
 425                 mono_thread_set_name_internal (thread, mono_string_new (mono_get_root_domain (), "Threadpool worker"), FALSE, TRUE, &error);
 426                 mono_error_assert_ok (&error);
 427
 428                 mono_thread_clr_state (thread, (MonoThreadState)~ThreadState_Background);
 429                 if (!mono_thread_test_state (thread , ThreadState_Background))
 430                         ves_icall_System_Threading_Thread_SetState (thread, ThreadState_Background);
 431
 432                 mono_thread_push_appdomain_ref (tpdomain->domain);
 433                 if (mono_domain_set (tpdomain->domain, FALSE)) {
 434                         MonoObject *exc = NULL, *res;
 435
 436                         res = try_invoke_perform_wait_callback (&exc, &error);
 437                         if (exc || !mono_error_ok(&error)) {
 438                                 if (exc == NULL)
 439                                         exc = (MonoObject *) mono_error_convert_to_exception (&error);
 440                                 else
 441                                         mono_error_cleanup (&error);
 442                                 mono_thread_internal_unhandled_exception (exc);
 443                         } else if (res && *(MonoBoolean*) mono_object_unbox (res) == FALSE) {
 444                                 retire = TRUE;
 445                         }
 446
 447                         mono_domain_set (mono_get_root_domain (), TRUE);
 448                 }
 449                 mono_thread_pop_appdomain_ref ();
 450
 451                 domains_lock ();
 452
 453                 tpdomain->threadpool_jobs --;
 454                 g_assert (tpdomain->threadpool_jobs >= 0);
 455
 456                 if (tpdomain->outstanding_request + tpdomain->threadpool_jobs == 0 && mono_domain_is_unloading (tpdomain->domain)) {
 457                         gboolean removed;
 458
 459                         removed = tpdomain_remove (tpdomain);
 460                         g_assert (removed);
 461
 462                         mono_coop_cond_signal (&tpdomain->cleanup_cond);
 463                         tpdomain = NULL;
 464                 }
 465
 466                 if (retire)
 467                         break;
 468
 469                 previous_tpdomain = tpdomain;
 470         }
 471
 472         domains_unlock ();
 473
 474         mono_coop_mutex_lock (&threadpool->threads_lock);
 475
 476         g_ptr_array_remove_fast (threadpool->threads, thread);
 477
 478         mono_coop_cond_signal (&threadpool->threads_exit_cond);
 479
 480         mono_coop_mutex_unlock (&threadpool->threads_lock);
 481
 482         COUNTER_ATOMIC (threadpool, counter, {
 483                 counter._.working --;
 484         });
 485
 486         mono_refcount_dec (threadpool);
 487 }
 488
 489 void
 490 mono_threadpool_cleanup (void)
 491 {
 492 #ifndef DISABLE_SOCKETS
 493         mono_threadpool_io_cleanup ();
 494 #endif
 495         mono_lazy_cleanup (&status, cleanup);
 496 }
 497
 498 MonoAsyncResult *
 499 mono_threadpool_begin_invoke (MonoDomain *domain, MonoObject *target, MonoMethod *method, gpointer *params, MonoError *error)
 500 {
 501         static MonoClass *async_call_klass = NULL;
 502         MonoMethodMessage *message;
 503         MonoAsyncResult *async_result;
 504         MonoAsyncCall *async_call;
 505         MonoDelegate *async_callback = NULL;
 506         MonoObject *state = NULL;
 507
 508         if (!async_call_klass)
 509                 async_call_klass = mono_class_load_from_name (mono_defaults.corlib, "System", "MonoAsyncCall");
 510
 511         mono_lazy_initialize (&status, initialize);
 512
 513         mono_error_init (error);
 514
 515         message = mono_method_call_message_new (method, params, mono_get_delegate_invoke (method->klass), (params != NULL) ? (&async_callback) : NULL, (params != NULL) ? (&state) : NULL, error);
 516         return_val_if_nok (error, NULL);
 517
 518         async_call = (MonoAsyncCall*) mono_object_new_checked (domain, async_call_klass, error);
 519         return_val_if_nok (error, NULL);
 520
 521         MONO_OBJECT_SETREF (async_call, msg, message);
 522         MONO_OBJECT_SETREF (async_call, state, state);
 523
 524         if (async_callback) {
 525                 MONO_OBJECT_SETREF (async_call, cb_method, mono_get_delegate_invoke (((MonoObject*) async_callback)->vtable->klass));
 526                 MONO_OBJECT_SETREF (async_call, cb_target, async_callback);
 527         }
 528
 529         async_result = mono_async_result_new (domain, NULL, async_call->state, NULL, (MonoObject*) async_call, error);
 530         return_val_if_nok (error, NULL);
 531         MONO_OBJECT_SETREF (async_result, async_delegate, target);
 532
 533         mono_threadpool_enqueue_work_item (domain, (MonoObject*) async_result, error);
 534         return_val_if_nok (error, NULL);
 535
 536         return async_result;
 537 }
 538
 539 MonoObject *
 540 mono_threadpool_end_invoke (MonoAsyncResult *ares, MonoArray **out_args, MonoObject **exc, MonoError *error)
 541 {
 542         MonoAsyncCall *ac;
 543
 544         mono_error_init (error);
 545         g_assert (exc);
 546         g_assert (out_args);
 547
 548         *exc = NULL;
 549         *out_args = NULL;
 550
 551         /* check if already finished */
 552         mono_monitor_enter ((MonoObject*) ares);
 553
 554         if (ares->endinvoke_called) {
 555                 mono_error_set_invalid_operation(error, "Delegate EndInvoke method called more than once");
 556                 mono_monitor_exit ((MonoObject*) ares);
 557                 return NULL;
 558         }
 559
 560         ares->endinvoke_called = 1;
 561
 562         /* wait until we are really finished */
 563         if (ares->completed) {
 564                 mono_monitor_exit ((MonoObject *) ares);
 565         } else {
 566                 gpointer wait_event;
 567                 if (ares->handle) {
 568                         wait_event = mono_wait_handle_get_handle ((MonoWaitHandle*) ares->handle);
 569                 } else {
 570                         wait_event = mono_w32event_create (TRUE, FALSE);
 571                         g_assert(wait_event);
 572                         MonoWaitHandle *wait_handle = mono_wait_handle_new (mono_object_domain (ares), wait_event, error);
 573                         if (!is_ok (error)) {
 574                                 mono_w32event_close (wait_event);
 575                                 return NULL;
 576                         }
 577                         MONO_OBJECT_SETREF (ares, handle, (MonoObject*) wait_handle);
 578                 }
 579                 mono_monitor_exit ((MonoObject*) ares);
 580                 MONO_ENTER_GC_SAFE;
 581 #ifdef HOST_WIN32
 582                 WaitForSingleObjectEx (wait_event, INFINITE, TRUE);
 583 #else
 584                 mono_w32handle_wait_one (wait_event, MONO_INFINITE_WAIT, TRUE);
 585 #endif
 586                 MONO_EXIT_GC_SAFE;
 587         }
 588
 589         ac = (MonoAsyncCall*) ares->object_data;
 590         g_assert (ac);
 591
 592         *exc = ac->msg->exc; /* FIXME: GC add write barrier */
 593         *out_args = ac->out_args;
 594         return ac->res;
 595 }
 596
 597 gboolean
 598 mono_threadpool_remove_domain_jobs (MonoDomain *domain, int timeout)
 599 {
 600         gint64 end;
 601         ThreadPoolDomain *tpdomain;
 602         gboolean ret;
 603
 604         g_assert (domain);
 605         g_assert (timeout >= -1);
 606
 607         g_assert (mono_domain_is_unloading (domain));
 608
 609         if (timeout != -1)
 610                 end = mono_msec_ticks () + timeout;
 611
 612 #ifndef DISABLE_SOCKETS
 613         mono_threadpool_io_remove_domain_jobs (domain);
 614         if (timeout != -1) {
 615                 if (mono_msec_ticks () > end)
 616                         return FALSE;
 617         }
 618 #endif
 619
 620         /*
 621          * Wait for all threads which execute jobs in the domain to exit.
 622          * The is_unloading () check in worker_request () ensures that
 623          * no new jobs are added after we enter the lock below.
 624          */
 625
 626         if (!mono_lazy_is_initialized (&status))
 627                 return TRUE;
 628
 629         mono_refcount_inc (threadpool);
 630
 631         domains_lock ();
 632
 633         tpdomain = tpdomain_get (domain, FALSE);
 634         if (!tpdomain) {
 635                 domains_unlock ();
 636                 mono_refcount_dec (threadpool);
 637                 return TRUE;
 638         }
 639
 640         ret = TRUE;
 641
 642         while (tpdomain->outstanding_request + tpdomain->threadpool_jobs > 0) {
 643                 if (timeout == -1) {
 644                         mono_coop_cond_wait (&tpdomain->cleanup_cond, &threadpool->domains_lock);
 645                 } else {
 646                         gint64 now;
 647                         gint res;
 648
 649                         now = mono_msec_ticks();
 650                         if (now > end) {
 651                                 ret = FALSE;
 652                                 break;
 653                         }
 654
 655                         res = mono_coop_cond_timedwait (&tpdomain->cleanup_cond, &threadpool->domains_lock, end - now);
 656                         if (res != 0) {
 657                                 ret = FALSE;
 658                                 break;
 659                         }
 660                 }
 661         }
 662
 663         /* Remove from the list the worker threads look at */
 664         tpdomain_remove (tpdomain);
 665
 666         domains_unlock ();
 667
 668         mono_coop_cond_destroy (&tpdomain->cleanup_cond);
 669         tpdomain_free (tpdomain);
 670
 671         mono_refcount_dec (threadpool);
 672
 673         return ret;
 674 }
 675
 676 void
 677 mono_threadpool_suspend (void)
 678 {
 679         if (threadpool)
 680                 mono_threadpool_worker_set_suspended (threadpool->worker, TRUE);
 681 }
 682
 683 void
 684 mono_threadpool_resume (void)
 685 {
 686         if (threadpool)
 687                 mono_threadpool_worker_set_suspended (threadpool->worker, FALSE);
 688 }
 689
 690 void
 691 ves_icall_System_Threading_ThreadPool_GetAvailableThreadsNative (gint32 *worker_threads, gint32 *completion_port_threads)
 692 {
 693         ThreadPoolCounter counter;
 694
 695         if (!worker_threads || !completion_port_threads)
 696                 return;
 697
 698         mono_lazy_initialize (&status, initialize);
 699
 700         counter = COUNTER_READ (threadpool);
 701
 702         *worker_threads = MAX (0, mono_threadpool_worker_get_max (threadpool->worker) - counter._.working);
 703         *completion_port_threads = threadpool->limit_io_max;
 704 }
 705
 706 void
 707 ves_icall_System_Threading_ThreadPool_GetMinThreadsNative (gint32 *worker_threads, gint32 *completion_port_threads)
 708 {
 709         if (!worker_threads || !completion_port_threads)
 710                 return;
 711
 712         mono_lazy_initialize (&status, initialize);
 713
 714         *worker_threads = mono_threadpool_worker_get_min (threadpool->worker);
 715         *completion_port_threads = threadpool->limit_io_min;
 716 }
 717
 718 void
 719 ves_icall_System_Threading_ThreadPool_GetMaxThreadsNative (gint32 *worker_threads, gint32 *completion_port_threads)
 720 {
 721         if (!worker_threads || !completion_port_threads)
 722                 return;
 723
 724         mono_lazy_initialize (&status, initialize);
 725
 726         *worker_threads = mono_threadpool_worker_get_max (threadpool->worker);
 727         *completion_port_threads = threadpool->limit_io_max;
 728 }
 729
 730 MonoBoolean
 731 ves_icall_System_Threading_ThreadPool_SetMinThreadsNative (gint32 worker_threads, gint32 completion_port_threads)
 732 {
 733         mono_lazy_initialize (&status, initialize);
 734
 735         if (completion_port_threads <= 0 || completion_port_threads > threadpool->limit_io_max)
 736                 return FALSE;
 737
 738         if (!mono_threadpool_worker_set_min (threadpool->worker, worker_threads))
 739                 return FALSE;
 740
 741         threadpool->limit_io_min = completion_port_threads;
 742
 743         return TRUE;
 744 }
 745
 746 MonoBoolean
 747 ves_icall_System_Threading_ThreadPool_SetMaxThreadsNative (gint32 worker_threads, gint32 completion_port_threads)
 748 {
 749         gint cpu_count = mono_cpu_count ();
 750
 751         mono_lazy_initialize (&status, initialize);
 752
 753         if (completion_port_threads < threadpool->limit_io_min || completion_port_threads < cpu_count)
 754                 return FALSE;
 755
 756         if (!mono_threadpool_worker_set_max (threadpool->worker, worker_threads))
 757                 return FALSE;
 758
 759         threadpool->limit_io_max = completion_port_threads;
 760
 761         return TRUE;
 762 }
 763
 764 void
 765 ves_icall_System_Threading_ThreadPool_InitializeVMTp (MonoBoolean *enable_worker_tracking)
 766 {
 767         if (enable_worker_tracking) {
 768                 // TODO implement some kind of switch to have the possibily to use it
 769                 *enable_worker_tracking = FALSE;
 770         }
 771
 772         mono_lazy_initialize (&status, initialize);
 773 }
 774
 775 MonoBoolean
 776 ves_icall_System_Threading_ThreadPool_NotifyWorkItemComplete (void)
 777 {
 778         if (mono_domain_is_unloading (mono_domain_get ()) || mono_runtime_is_shutting_down ())
 779                 return FALSE;
 780
 781         return mono_threadpool_worker_notify_completed (threadpool->worker);
 782 }
 783
 784 void
 785 ves_icall_System_Threading_ThreadPool_NotifyWorkItemProgressNative (void)
 786 {
 787         mono_threadpool_worker_notify_completed (threadpool->worker);
 788 }
 789
 790 void
 791 ves_icall_System_Threading_ThreadPool_ReportThreadStatus (MonoBoolean is_working)
 792 {
 793         // TODO
 794         MonoError error;
 795         mono_error_set_not_implemented (&error, "");
 796         mono_error_set_pending_exception (&error);
 797 }
 798
 799 MonoBoolean
 800 ves_icall_System_Threading_ThreadPool_RequestWorkerThread (void)
 801 {
 802         MonoDomain *domain;
 803         ThreadPoolDomain *tpdomain;
 804         ThreadPoolCounter counter;
 805
 806         domain = mono_domain_get ();
 807         if (mono_domain_is_unloading (domain))
 808                 return FALSE;
 809
 810         if (!mono_refcount_tryinc (threadpool)) {
 811                 /* threadpool has been destroyed, we are shutting down */
 812                 return FALSE;
 813         }
 814
 815         domains_lock ();
 816
 817         /* synchronize with mono_threadpool_remove_domain_jobs */
 818         if (mono_domain_is_unloading (domain)) {
 819                 domains_unlock ();
 820                 mono_refcount_dec (threadpool);
 821                 return FALSE;
 822         }
 823
 824         tpdomain = tpdomain_get (domain, TRUE);
 825         g_assert (tpdomain);
 826
 827         tpdomain->outstanding_request ++;
 828         g_assert (tpdomain->outstanding_request >= 1);
 829
 830         domains_unlock ();
 831
 832         COUNTER_ATOMIC (threadpool, counter, {
 833                 if (counter._.starting == 16) {
 834                         mono_refcount_dec (threadpool);
 835                         return TRUE;
 836                 }
 837
 838                 counter._.starting ++;
 839         });
 840
 841         mono_threadpool_worker_enqueue (threadpool->worker, worker_callback, NULL);
 842
 843         return TRUE;
 844 }
 845
 846 MonoBoolean G_GNUC_UNUSED
 847 ves_icall_System_Threading_ThreadPool_PostQueuedCompletionStatus (MonoNativeOverlapped *native_overlapped)
 848 {
 849         /* This copy the behavior of the current Mono implementation */
 850         MonoError error;
 851         mono_error_set_not_implemented (&error, "");
 852         mono_error_set_pending_exception (&error);
 853         return FALSE;
 854 }
 855
 856 MonoBoolean G_GNUC_UNUSED
 857 ves_icall_System_Threading_ThreadPool_BindIOCompletionCallbackNative (gpointer file_handle)
 858 {
 859         /* This copy the behavior of the current Mono implementation */
 860         return TRUE;
 861 }
 862
 863 MonoBoolean G_GNUC_UNUSED
 864 ves_icall_System_Threading_ThreadPool_IsThreadPoolHosted (void)
 865 {
 866         return FALSE;
 867 }