2 * mono-threads.c: Low-level threading
5 * Rodrigo Kumpera (kumpera@gmail.com)
7 * Copyright 2011 Novell, Inc (http://www.novell.com)
8 * Copyright 2011 Xamarin, Inc (http://www.xamarin.com)
9 * Licensed under the MIT license. See LICENSE file in the project root for full license information.
14 /* enable pthread extensions */
16 #define _DARWIN_C_SOURCE
19 #include <mono/utils/mono-compiler.h>
20 #include <mono/utils/mono-os-semaphore.h>
21 #include <mono/utils/mono-threads.h>
22 #include <mono/utils/mono-tls.h>
23 #include <mono/utils/hazard-pointer.h>
24 #include <mono/utils/mono-memory-model.h>
25 #include <mono/utils/mono-mmap.h>
26 #include <mono/utils/atomic.h>
27 #include <mono/utils/mono-time.h>
28 #include <mono/utils/mono-lazy-init.h>
29 #include <mono/utils/mono-coop-mutex.h>
30 #include <mono/utils/mono-coop-semaphore.h>
31 #include <mono/utils/mono-threads-coop.h>
32 #include <mono/utils/mono-threads-debug.h>
33 #include <mono/utils/os-event.h>
38 #include <mono/utils/mach-support.h>
42 Mutex that makes sure only a single thread can be suspending others.
43 Suspend is a very racy operation since it requires restarting until
44 the target thread is not on an unsafe region.
46 We could implement this using critical regions, but would be much much
47 harder for an operation that is hardly performance critical.
49 The GC has to acquire this lock before starting a STW to make sure
50 a runtime suspend won't make it wronly see a thread in a safepoint
51 when it is in fact not.
53 This has to be a naked locking primitive, and not a coop aware one, as
54 it needs to be usable when destroying thread_info_key, the TLS key for
55 the current MonoThreadInfo. In this case, mono_thread_info_current_unchecked,
56 (which is used inside MONO_ENTER_GC_SAFE), would return NULL, leading
57 to an assertion error. We then simply switch state manually in
58 mono_thread_info_suspend_lock_with_info.
60 static MonoSemType global_suspend_semaphore;
62 static size_t thread_info_size;
63 static MonoThreadInfoCallbacks threads_callbacks;
64 static MonoThreadInfoRuntimeCallbacks runtime_callbacks;
65 static MonoNativeTlsKey thread_info_key, thread_exited_key;
67 static __thread guint32 tls_small_id MONO_TLS_FAST;
69 static MonoNativeTlsKey small_id_key;
71 static MonoLinkedListSet thread_list;
72 static gboolean mono_threads_inited = FALSE;
74 static MonoSemType suspend_semaphore;
75 static size_t pending_suspends;
77 #define mono_thread_info_run_state(info) (((MonoThreadInfo*)info)->thread_state & THREAD_STATE_MASK)
80 #define SLEEP_DURATION_BEFORE_WARNING (50)
82 #define SLEEP_DURATION_BEFORE_ABORT MONO_INFINITE_WAIT
84 static guint32 sleepWarnDuration = SLEEP_DURATION_BEFORE_WARNING,
85 sleepAbortDuration = SLEEP_DURATION_BEFORE_ABORT;
87 static int suspend_posts, resume_posts, abort_posts, waits_done, pending_ops;
90 mono_threads_notify_initiator_of_abort (MonoThreadInfo* info)
92 THREADS_SUSPEND_DEBUG ("[INITIATOR-NOTIFY-ABORT] %p\n", mono_thread_info_get_tid (info));
93 InterlockedIncrement (&abort_posts);
94 mono_os_sem_post (&suspend_semaphore);
98 mono_threads_notify_initiator_of_suspend (MonoThreadInfo* info)
100 THREADS_SUSPEND_DEBUG ("[INITIATOR-NOTIFY-SUSPEND] %p\n", mono_thread_info_get_tid (info));
101 InterlockedIncrement (&suspend_posts);
102 mono_os_sem_post (&suspend_semaphore);
106 mono_threads_notify_initiator_of_resume (MonoThreadInfo* info)
108 THREADS_SUSPEND_DEBUG ("[INITIATOR-NOTIFY-RESUME] %p\n", mono_thread_info_get_tid (info));
109 InterlockedIncrement (&resume_posts);
110 mono_os_sem_post (&suspend_semaphore);
114 begin_async_suspend (MonoThreadInfo *info, gboolean interrupt_kernel)
116 if (mono_threads_is_coop_enabled ()) {
117 /* There's nothing else to do after we async request the thread to suspend */
118 mono_threads_add_to_pending_operation_set (info);
122 return mono_threads_suspend_begin_async_suspend (info, interrupt_kernel);
126 check_async_suspend (MonoThreadInfo *info)
128 if (mono_threads_is_coop_enabled ()) {
129 /* Async suspend can't async fail on coop */
133 return mono_threads_suspend_check_suspend_result (info);
137 resume_async_suspended (MonoThreadInfo *info)
139 if (mono_threads_is_coop_enabled ())
140 g_assert_not_reached ();
142 g_assert (mono_threads_suspend_begin_async_resume (info));
146 resume_self_suspended (MonoThreadInfo* info)
148 THREADS_SUSPEND_DEBUG ("**BEGIN self-resume %p\n", mono_thread_info_get_tid (info));
149 mono_os_sem_post (&info->resume_semaphore);
153 mono_thread_info_wait_for_resume (MonoThreadInfo* info)
156 THREADS_SUSPEND_DEBUG ("**WAIT self-resume %p\n", mono_thread_info_get_tid (info));
157 res = mono_os_sem_wait (&info->resume_semaphore, MONO_SEM_FLAGS_NONE);
158 g_assert (res != -1);
162 resume_blocking_suspended (MonoThreadInfo* info)
164 THREADS_SUSPEND_DEBUG ("**BEGIN blocking-resume %p\n", mono_thread_info_get_tid (info));
165 mono_os_sem_post (&info->resume_semaphore);
169 mono_threads_add_to_pending_operation_set (MonoThreadInfo* info)
171 THREADS_SUSPEND_DEBUG ("added %p to pending suspend\n", mono_thread_info_get_tid (info));
173 InterlockedIncrement (&pending_ops);
177 mono_threads_begin_global_suspend (void)
179 size_t ps = pending_suspends;
180 if (G_UNLIKELY (ps != 0))
181 g_error ("pending_suspends = %d, but must be 0", ps);
182 THREADS_SUSPEND_DEBUG ("------ BEGIN GLOBAL OP sp %d rp %d ap %d wd %d po %d (sp + rp + ap == wd) (wd == po)\n", suspend_posts, resume_posts,
183 abort_posts, waits_done, pending_ops);
184 g_assert ((suspend_posts + resume_posts + abort_posts) == waits_done);
185 mono_threads_coop_begin_global_suspend ();
189 mono_threads_end_global_suspend (void)
191 size_t ps = pending_suspends;
192 if (G_UNLIKELY (ps != 0))
193 g_error ("pending_suspends = %d, but must be 0", ps);
194 THREADS_SUSPEND_DEBUG ("------ END GLOBAL OP sp %d rp %d ap %d wd %d po %d\n", suspend_posts, resume_posts,
195 abort_posts, waits_done, pending_ops);
196 g_assert ((suspend_posts + resume_posts + abort_posts) == waits_done);
197 mono_threads_coop_end_global_suspend ();
203 MonoThreadInfo *cur = mono_thread_info_current ();
205 MOSTLY_ASYNC_SAFE_PRINTF ("STATE CUE CARD: (? means a positive number, usually 1 or 2, * means any number)\n");
206 MOSTLY_ASYNC_SAFE_PRINTF ("\t0x0\t- starting (GOOD, unless the thread is running managed code)\n");
207 MOSTLY_ASYNC_SAFE_PRINTF ("\t0x1\t- running (BAD, unless it's the gc thread)\n");
208 MOSTLY_ASYNC_SAFE_PRINTF ("\t0x2\t- detached (GOOD, unless the thread is running managed code)\n");
209 MOSTLY_ASYNC_SAFE_PRINTF ("\t0x?03\t- async suspended (GOOD)\n");
210 MOSTLY_ASYNC_SAFE_PRINTF ("\t0x?04\t- self suspended (GOOD)\n");
211 MOSTLY_ASYNC_SAFE_PRINTF ("\t0x?05\t- async suspend requested (BAD)\n");
212 MOSTLY_ASYNC_SAFE_PRINTF ("\t0x?06\t- self suspend requested (BAD)\n");
213 MOSTLY_ASYNC_SAFE_PRINTF ("\t0x*07\t- blocking (GOOD)\n");
214 MOSTLY_ASYNC_SAFE_PRINTF ("\t0x?08\t- blocking with pending suspend (GOOD)\n");
216 FOREACH_THREAD_SAFE (info) {
218 char thread_name [256] = { 0 };
219 pthread_getname_np (mono_thread_info_get_tid (info), thread_name, 255);
221 MOSTLY_ASYNC_SAFE_PRINTF ("--thread %p id %p [%p] (%s) state %x %s\n", info, (void *) mono_thread_info_get_tid (info), (void*)(size_t)info->native_handle, thread_name, info->thread_state, info == cur ? "GC INITIATOR" : "" );
223 MOSTLY_ASYNC_SAFE_PRINTF ("--thread %p id %p [%p] state %x %s\n", info, (void *) mono_thread_info_get_tid (info), (void*)(size_t)info->native_handle, info->thread_state, info == cur ? "GC INITIATOR" : "" );
225 } FOREACH_THREAD_SAFE_END
229 mono_threads_wait_pending_operations (void)
232 int c = pending_suspends;
234 /* Wait threads to park */
235 THREADS_SUSPEND_DEBUG ("[INITIATOR-WAIT-COUNT] %d\n", c);
236 if (pending_suspends) {
237 MonoStopwatch suspension_time;
238 mono_stopwatch_start (&suspension_time);
239 for (i = 0; i < pending_suspends; ++i) {
240 THREADS_SUSPEND_DEBUG ("[INITIATOR-WAIT-WAITING]\n");
241 InterlockedIncrement (&waits_done);
242 if (mono_os_sem_timedwait (&suspend_semaphore, sleepAbortDuration, MONO_SEM_FLAGS_NONE) == MONO_SEM_TIMEDWAIT_RET_SUCCESS)
244 mono_stopwatch_stop (&suspension_time);
248 MOSTLY_ASYNC_SAFE_PRINTF ("WAITING for %d threads, got %d suspended\n", (int)pending_suspends, i);
249 g_error ("suspend_thread suspend took %d ms, which is more than the allowed %d ms", (int)mono_stopwatch_elapsed_ms (&suspension_time), sleepAbortDuration);
251 mono_stopwatch_stop (&suspension_time);
252 THREADS_SUSPEND_DEBUG ("Suspending %d threads took %d ms.\n", (int)pending_suspends, (int)mono_stopwatch_elapsed_ms (&suspension_time));
256 pending_suspends = 0;
262 //Thread initialization code
265 mono_hazard_pointer_clear_all (MonoThreadHazardPointers *hp, int retain)
268 mono_hazard_pointer_clear (hp, 0);
270 mono_hazard_pointer_clear (hp, 1);
272 mono_hazard_pointer_clear (hp, 2);
276 If return non null Hazard Pointer 1 holds the return value.
279 mono_thread_info_lookup (MonoNativeThreadId id)
281 MonoThreadHazardPointers *hp = mono_hazard_pointer_get ();
283 if (!mono_lls_find (&thread_list, hp, (uintptr_t)id)) {
284 mono_hazard_pointer_clear_all (hp, -1);
288 mono_hazard_pointer_clear_all (hp, 1);
289 return (MonoThreadInfo *) mono_hazard_pointer_get_val (hp, 1);
293 mono_thread_info_insert (MonoThreadInfo *info)
295 MonoThreadHazardPointers *hp = mono_hazard_pointer_get ();
297 if (!mono_lls_insert (&thread_list, hp, (MonoLinkedListSetNode*)info)) {
298 mono_hazard_pointer_clear_all (hp, -1);
302 mono_hazard_pointer_clear_all (hp, -1);
307 mono_thread_info_remove (MonoThreadInfo *info)
309 MonoThreadHazardPointers *hp = mono_hazard_pointer_get ();
312 THREADS_DEBUG ("removing info %p\n", info);
313 res = mono_lls_remove (&thread_list, hp, (MonoLinkedListSetNode*)info);
314 mono_hazard_pointer_clear_all (hp, -1);
319 free_thread_info (gpointer mem)
321 MonoThreadInfo *info = (MonoThreadInfo *) mem;
323 mono_os_sem_destroy (&info->resume_semaphore);
324 mono_threads_suspend_free (info);
330 mono_thread_info_register_small_id (void)
332 int small_id = mono_thread_small_id_alloc ();
333 #ifdef HAVE_KW_THREAD
334 tls_small_id = small_id;
336 mono_native_tls_set_value (small_id_key, GUINT_TO_POINTER (small_id + 1));
342 register_thread (MonoThreadInfo *info, gpointer baseptr)
345 guint8 *staddr = NULL;
346 int small_id = mono_thread_info_register_small_id ();
348 mono_thread_info_set_tid (info, mono_native_thread_id_get ());
349 info->small_id = small_id;
351 info->handle = g_new0 (MonoThreadHandle, 1);
352 info->handle->ref = 1;
353 mono_os_event_init (&info->handle->event, FALSE);
355 mono_os_sem_init (&info->resume_semaphore, 0);
357 /*set TLS early so SMR works */
358 mono_native_tls_set_value (thread_info_key, info);
360 THREADS_DEBUG ("registering info %p tid %p small id %x\n", info, mono_thread_info_get_tid (info), info->small_id);
362 if (threads_callbacks.thread_register) {
363 if (threads_callbacks.thread_register (info, baseptr) == NULL) {
364 // g_warning ("thread registation failed\n");
365 mono_native_tls_set_value (thread_info_key, NULL);
371 mono_thread_info_get_stack_bounds (&staddr, &stsize);
374 info->stack_start_limit = staddr;
375 info->stack_end = staddr + stsize;
377 info->stackdata = g_byte_array_new ();
379 mono_threads_suspend_register (info);
382 Transition it before taking any locks or publishing itself to reduce the chance
383 of others witnessing a detached thread.
384 We can reasonably expect that until this thread gets published, no other thread will
385 try to manipulate it.
387 mono_threads_transition_attach (info);
388 mono_thread_info_suspend_lock ();
389 /*If this fail it means a given thread has been registered twice, which doesn't make sense. */
390 result = mono_thread_info_insert (info);
392 mono_thread_info_suspend_unlock ();
397 mono_thread_info_suspend_lock_with_info (MonoThreadInfo *info);
400 mono_threads_signal_thread_handle (MonoThreadHandle* thread_handle);
403 unregister_thread (void *arg)
405 gpointer gc_unsafe_stackdata;
406 MonoThreadInfo *info;
411 info = (MonoThreadInfo *) arg;
413 g_assert (mono_thread_info_is_current (info));
414 g_assert (mono_thread_info_is_live (info));
416 small_id = info->small_id;
418 /* We only enter the GC unsafe region, as when exiting this function, the thread
419 * will be detached, and the current MonoThreadInfo* will be destroyed. */
420 mono_threads_enter_gc_unsafe_region_unbalanced_with_info (info, &gc_unsafe_stackdata);
422 THREADS_DEBUG ("unregistering info %p\n", info);
424 mono_native_tls_set_value (thread_exited_key, GUINT_TO_POINTER (1));
427 * TLS destruction order is not reliable so small_id might be cleaned up
430 #ifndef HAVE_KW_THREAD
431 mono_native_tls_set_value (small_id_key, GUINT_TO_POINTER (info->small_id + 1));
434 /* we need to duplicate it, as the info->handle is going
435 * to be closed when unregistering from the platform */
436 handle = mono_threads_open_thread_handle (info->handle);
439 First perform the callback that requires no locks.
440 This callback has the potential of taking other locks, so we do it before.
441 After it completes, the thread remains functional.
443 if (threads_callbacks.thread_detach)
444 threads_callbacks.thread_detach (info);
446 mono_thread_info_suspend_lock_with_info (info);
449 Now perform the callback that must be done under locks.
450 This will render the thread useless and non-suspendable, so it must
451 be done while holding the suspend lock to give no other thread chance
454 if (threads_callbacks.thread_unregister)
455 threads_callbacks.thread_unregister (info);
457 /* The thread is no longer active, so unref its handle */
458 mono_threads_close_thread_handle (info->handle);
461 result = mono_thread_info_remove (info);
463 mono_threads_transition_detach (info);
465 mono_thread_info_suspend_unlock ();
467 g_byte_array_free (info->stackdata, /*free_segment=*/TRUE);
469 /*now it's safe to free the thread info.*/
470 mono_thread_hazardous_try_free (info, free_thread_info);
471 /* Pump the HP queue */
472 mono_thread_hazardous_try_free_some ();
474 mono_thread_small_id_free (small_id);
476 mono_threads_signal_thread_handle (handle);
478 mono_threads_close_thread_handle (handle);
482 thread_exited_dtor (void *arg)
484 #if defined(__MACH__)
486 * Since we use pthread dtors to clean up thread data, if a thread
487 * is attached to the runtime by another pthread dtor after our dtor
488 * has ran, it will never be detached, leading to various problems
489 * since the thread ids etc. will be reused while they are still in
490 * the threads hashtables etc.
491 * Dtors are called in a loop until all user tls entries are 0,
492 * but the loop has a maximum count (4), so if we set the tls
493 * variable every time, it will remain set when system tls dtors
494 * are ran. This allows mono_thread_info_is_exiting () to detect
495 * whenever the thread is exiting, even if it is executed from a
496 * system tls dtor (i.e. obj-c dealloc methods).
498 mono_native_tls_set_value (thread_exited_key, GUINT_TO_POINTER (1));
503 mono_thread_info_current_unchecked (void)
505 return mono_threads_inited ? (MonoThreadInfo*)mono_native_tls_get_value (thread_info_key) : NULL;
510 mono_thread_info_current (void)
512 MonoThreadInfo *info = (MonoThreadInfo*)mono_native_tls_get_value (thread_info_key);
516 info = mono_thread_info_lookup (mono_native_thread_id_get ()); /*info on HP1*/
519 We might be called during thread cleanup, but we cannot be called after cleanup as happened.
520 The way to distinguish between before, during and after cleanup is the following:
522 -If the TLS key is set, cleanup has not begun;
523 -If the TLS key is clean, but the thread remains registered, cleanup is in progress;
524 -If the thread is nowhere to be found, cleanup has finished.
526 We cannot function after cleanup since there's no way to ensure what will happen.
530 /*We're looking up the current thread which will not be freed until we finish running, so no need to keep it on a HP */
531 mono_hazard_pointer_clear (mono_hazard_pointer_get (), 1);
537 mono_thread_info_get_small_id (void)
539 #ifdef HAVE_KW_THREAD
542 gpointer val = mono_native_tls_get_value (small_id_key);
545 return GPOINTER_TO_INT (val) - 1;
550 mono_thread_info_list_head (void)
556 * mono_threads_attach_tools_thread
558 * Attach the current thread as a tool thread. DON'T USE THIS FUNCTION WITHOUT READING ALL DISCLAIMERS.
560 * A tools thread is a very special kind of thread that needs access to core runtime facilities but should
561 * not be counted as a regular thread for high order facilities such as executing managed code or accessing
564 * This is intended only to tools such as a profiler than needs to be able to use our lock-free support when
565 * doing things like resolving backtraces in their background processing thread.
568 mono_threads_attach_tools_thread (void)
571 MonoThreadInfo *info;
573 /* Must only be called once */
574 g_assert (!mono_native_tls_get_value (thread_info_key));
576 while (!mono_threads_inited) {
577 mono_thread_info_usleep (10);
580 info = mono_thread_info_attach (&dummy);
583 info->tools_thread = TRUE;
587 mono_thread_info_attach (void *baseptr)
589 MonoThreadInfo *info;
590 if (!mono_threads_inited)
593 /* This can happen from DllMain(DLL_THREAD_ATTACH) on Windows, if a
594 * thread is created before an embedding API user initialized Mono. */
595 THREADS_DEBUG ("mono_thread_info_attach called before mono_threads_init\n");
598 g_assert (mono_threads_inited);
601 info = (MonoThreadInfo *) mono_native_tls_get_value (thread_info_key);
603 info = (MonoThreadInfo *) g_malloc0 (thread_info_size);
604 THREADS_DEBUG ("attaching %p\n", info);
605 if (!register_thread (info, baseptr))
607 } else if (threads_callbacks.thread_attach) {
608 threads_callbacks.thread_attach (info);
614 mono_thread_info_detach (void)
616 MonoThreadInfo *info;
617 if (!mono_threads_inited)
619 /* This can happen from DllMain(THREAD_DETACH) on Windows, if a thread
620 * is created before an embedding API user initialized Mono. */
621 THREADS_DEBUG ("mono_thread_info_detach called before mono_threads_init\n");
624 info = (MonoThreadInfo *) mono_native_tls_get_value (thread_info_key);
626 THREADS_DEBUG ("detaching %p\n", info);
627 unregister_thread (info);
628 mono_native_tls_set_value (thread_info_key, NULL);
633 * mono_thread_info_is_exiting:
635 * Return whenever the current thread is exiting, i.e. it is running pthread
639 mono_thread_info_is_exiting (void)
641 #if defined(__MACH__)
642 if (mono_native_tls_get_value (thread_exited_key) == GUINT_TO_POINTER (1))
650 thread_info_key_dtor (void *arg)
652 /* Put the MonoThreadInfo back for the duration of the
653 * unregister code. In some circumstances the thread needs to
654 * take the GC lock which may block which requires a coop
655 * state transition. */
656 mono_native_tls_set_value (thread_info_key, arg);
657 unregister_thread (arg);
658 mono_native_tls_set_value (thread_info_key, NULL);
663 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t info_size)
666 threads_callbacks = *callbacks;
667 thread_info_size = info_size;
668 const char *sleepLimit;
670 res = mono_native_tls_alloc (&thread_info_key, NULL);
671 res = mono_native_tls_alloc (&thread_exited_key, NULL);
673 res = mono_native_tls_alloc (&thread_info_key, (void *) thread_info_key_dtor);
674 res = mono_native_tls_alloc (&thread_exited_key, (void *) thread_exited_dtor);
679 #ifndef HAVE_KW_THREAD
680 res = mono_native_tls_alloc (&small_id_key, NULL);
684 if ((sleepLimit = g_getenv ("MONO_SLEEP_ABORT_LIMIT")) != NULL) {
686 long threshold = strtol(sleepLimit, NULL, 10);
687 if ((errno == 0) && (threshold >= 40)) {
688 sleepAbortDuration = threshold;
689 sleepWarnDuration = threshold / 20;
691 g_warning("MONO_SLEEP_ABORT_LIMIT must be a number >= 40");
694 mono_os_sem_init (&global_suspend_semaphore, 1);
695 mono_os_sem_init (&suspend_semaphore, 0);
697 mono_lls_init (&thread_list, NULL);
698 mono_thread_smr_init ();
699 mono_threads_suspend_init ();
700 mono_threads_suspend_init_signals ();
701 mono_threads_coop_init ();
703 #if defined(__MACH__)
704 mono_mach_init (thread_info_key);
707 mono_threads_inited = TRUE;
709 g_assert (sizeof (MonoNativeThreadId) <= sizeof (uintptr_t));
713 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks)
715 runtime_callbacks = *callbacks;
718 MonoThreadInfoRuntimeCallbacks *
719 mono_threads_get_runtime_callbacks (void)
721 return &runtime_callbacks;
725 mono_thread_info_core_resume (MonoThreadInfo *info)
727 gboolean res = FALSE;
729 switch (mono_threads_transition_request_resume (info)) {
736 case ResumeInitSelfResume:
737 resume_self_suspended (info);
740 case ResumeInitAsyncResume:
741 resume_async_suspended (info);
744 case ResumeInitBlockingResume:
745 resume_blocking_suspended (info);
754 mono_thread_info_resume (MonoNativeThreadId tid)
756 gboolean result; /* don't initialize it so the compiler can catch unitilized paths. */
757 MonoThreadHazardPointers *hp = mono_hazard_pointer_get ();
758 MonoThreadInfo *info;
760 THREADS_SUSPEND_DEBUG ("RESUMING tid %p\n", (void*)tid);
762 mono_thread_info_suspend_lock ();
764 info = mono_thread_info_lookup (tid); /*info on HP1*/
770 result = mono_thread_info_core_resume (info);
772 //Wait for the pending resume to finish
773 mono_threads_wait_pending_operations ();
776 mono_thread_info_suspend_unlock ();
777 mono_hazard_pointer_clear (hp, 1);
782 mono_thread_info_begin_suspend (MonoThreadInfo *info)
784 switch (mono_threads_transition_request_async_suspension (info)) {
785 case AsyncSuspendAlreadySuspended:
786 case AsyncSuspendBlocking:
788 case AsyncSuspendWait:
789 mono_threads_add_to_pending_operation_set (info);
791 case AsyncSuspendInitSuspend:
792 return begin_async_suspend (info, FALSE);
794 g_assert_not_reached ();
799 mono_thread_info_begin_resume (MonoThreadInfo *info)
801 return mono_thread_info_core_resume (info);
805 FIXME fix cardtable WB to be out of line and check with the runtime if the target is not the
806 WB trampoline. Another option is to encode wb ranges in MonoJitInfo, but that is somewhat hard.
809 is_thread_in_critical_region (MonoThreadInfo *info)
813 gpointer stack_start;
814 MonoThreadUnwindState *state;
816 /* Are we inside a system critical region? */
817 if (info->inside_critical_region)
820 /* Are we inside a GC critical region? */
821 if (threads_callbacks.mono_thread_in_critical_region && threads_callbacks.mono_thread_in_critical_region (info)) {
825 /* The target thread might be shutting down and the domain might be null, which means no managed code left to run. */
826 state = mono_thread_info_get_suspend_state (info);
827 if (!state->unwind_data [MONO_UNWIND_DATA_DOMAIN])
830 stack_start = MONO_CONTEXT_GET_SP (&state->ctx);
831 /* altstack signal handler, sgen can't handle them, so we treat them as critical */
832 if (stack_start < info->stack_start_limit || stack_start >= info->stack_end)
835 if (threads_callbacks.ip_in_critical_region)
836 return threads_callbacks.ip_in_critical_region ((MonoDomain *) state->unwind_data [MONO_UNWIND_DATA_DOMAIN], (char *) MONO_CONTEXT_GET_IP (&state->ctx));
838 ji = mono_jit_info_table_find (
839 (MonoDomain *) state->unwind_data [MONO_UNWIND_DATA_DOMAIN],
840 (char *) MONO_CONTEXT_GET_IP (&state->ctx));
845 method = mono_jit_info_get_method (ji);
847 return threads_callbacks.mono_method_is_critical (method);
851 mono_thread_info_in_critical_location (MonoThreadInfo *info)
853 return is_thread_in_critical_region (info);
857 The return value is only valid until a matching mono_thread_info_resume is called
859 static MonoThreadInfo*
860 suspend_sync (MonoNativeThreadId tid, gboolean interrupt_kernel)
862 MonoThreadHazardPointers *hp = mono_hazard_pointer_get ();
863 MonoThreadInfo *info = mono_thread_info_lookup (tid); /*info on HP1*/
867 switch (mono_threads_transition_request_async_suspension (info)) {
868 case AsyncSuspendAlreadySuspended:
869 mono_hazard_pointer_clear (hp, 1); //XXX this is questionable we got to clean the suspend/resume nonsense of critical sections
871 case AsyncSuspendWait:
872 mono_threads_add_to_pending_operation_set (info);
874 case AsyncSuspendInitSuspend:
875 if (!begin_async_suspend (info, interrupt_kernel)) {
876 mono_hazard_pointer_clear (hp, 1);
880 case AsyncSuspendBlocking:
881 if (interrupt_kernel && mono_threads_suspend_needs_abort_syscall ())
882 mono_threads_suspend_abort_syscall (info);
886 g_assert_not_reached ();
889 //Wait for the pending suspend to finish
890 mono_threads_wait_pending_operations ();
892 if (!check_async_suspend (info)) {
893 mono_thread_info_core_resume (info);
894 mono_threads_wait_pending_operations ();
895 mono_hazard_pointer_clear (hp, 1);
901 static MonoThreadInfo*
902 suspend_sync_nolock (MonoNativeThreadId id, gboolean interrupt_kernel)
904 MonoThreadInfo *info = NULL;
905 int sleep_duration = 0;
907 if (!(info = suspend_sync (id, interrupt_kernel))) {
908 mono_hazard_pointer_clear (mono_hazard_pointer_get (), 1);
912 /*WARNING: We now are in interrupt context until we resume the thread. */
913 if (!is_thread_in_critical_region (info))
916 if (!mono_thread_info_core_resume (info)) {
917 mono_hazard_pointer_clear (mono_hazard_pointer_get (), 1);
920 THREADS_SUSPEND_DEBUG ("RESTARTED thread tid %p\n", (void*)id);
922 /* Wait for the pending resume to finish */
923 mono_threads_wait_pending_operations ();
925 if (sleep_duration == 0)
926 mono_thread_info_yield ();
928 g_usleep (sleep_duration);
930 sleep_duration += 10;
936 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data)
939 MonoThreadInfo *info = NULL;
940 MonoThreadHazardPointers *hp = mono_hazard_pointer_get ();
942 THREADS_SUSPEND_DEBUG ("SUSPENDING tid %p\n", (void*)id);
943 /*FIXME: unify this with self-suspend*/
944 g_assert (id != mono_native_thread_id_get ());
946 /* This can block during stw */
947 mono_thread_info_suspend_lock ();
948 mono_threads_begin_global_suspend ();
950 info = suspend_sync_nolock (id, interrupt_kernel);
954 switch (result = callback (info, user_data)) {
955 case MonoResumeThread:
956 mono_hazard_pointer_set (hp, 1, info);
957 mono_thread_info_core_resume (info);
958 mono_threads_wait_pending_operations ();
961 g_assert (!mono_threads_is_coop_enabled ());
964 g_error ("Invalid suspend_and_run callback return value %d", result);
968 mono_hazard_pointer_clear (hp, 1);
969 mono_threads_end_global_suspend ();
970 mono_thread_info_suspend_unlock ();
974 Inject an assynchronous call into the target thread. The target thread must be suspended and
975 only a single async call can be setup for a given suspend cycle.
976 This async call must cause stack unwinding as the current implementation doesn't save enough state
977 to resume execution of the top-of-stack function. It's an acceptable limitation since this is
978 currently used only to deliver exceptions.
981 mono_thread_info_setup_async_call (MonoThreadInfo *info, void (*target_func)(void*), void *user_data)
983 /* An async call can only be setup on an async suspended thread */
984 g_assert (mono_thread_info_run_state (info) == STATE_ASYNC_SUSPENDED);
985 /*FIXME this is a bad assert, we probably should do proper locking and fail if one is already set*/
986 g_assert (!info->async_target);
987 info->async_target = target_func;
988 /* This is not GC tracked */
989 info->user_data = user_data;
993 The suspend lock is held during any suspend in progress.
994 A GC that has safepoints must take this lock as part of its
995 STW to make sure no unsafe pending suspend is in progress.
999 mono_thread_info_suspend_lock_with_info (MonoThreadInfo *info)
1002 g_assert (mono_thread_info_is_current (info));
1003 g_assert (mono_thread_info_is_live (info));
1005 MONO_ENTER_GC_SAFE_WITH_INFO(info);
1007 int res = mono_os_sem_wait (&global_suspend_semaphore, MONO_SEM_FLAGS_NONE);
1008 g_assert (res != -1);
1010 MONO_EXIT_GC_SAFE_WITH_INFO;
1014 mono_thread_info_suspend_lock (void)
1016 mono_thread_info_suspend_lock_with_info (mono_thread_info_current_unchecked ());
1020 mono_thread_info_suspend_unlock (void)
1022 mono_os_sem_post (&global_suspend_semaphore);
1026 * This is a very specific function whose only purpose is to
1027 * break a given thread from socket syscalls.
1029 * This only exists because linux won't fail a call to connect
1030 * if the underlying is closed.
1032 * TODO We should cleanup and unify this with the other syscall abort
1036 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid)
1038 MonoThreadHazardPointers *hp;
1039 MonoThreadInfo *info;
1041 if (tid == mono_native_thread_id_get () || !mono_threads_suspend_needs_abort_syscall ())
1044 hp = mono_hazard_pointer_get ();
1045 info = mono_thread_info_lookup (tid);
1049 if (mono_thread_info_run_state (info) == STATE_DETACHED) {
1050 mono_hazard_pointer_clear (hp, 1);
1054 mono_thread_info_suspend_lock ();
1055 mono_threads_begin_global_suspend ();
1057 mono_threads_suspend_abort_syscall (info);
1058 mono_threads_wait_pending_operations ();
1060 mono_hazard_pointer_clear (hp, 1);
1062 mono_threads_end_global_suspend ();
1063 mono_thread_info_suspend_unlock ();
1067 * mono_thread_info_set_is_async_context:
1069 * Set whenever the current thread is in an async context. Some runtime functions might behave
1070 * differently while in an async context in order to be async safe.
1073 mono_thread_info_set_is_async_context (gboolean async_context)
1075 MonoThreadInfo *info = mono_thread_info_current ();
1078 info->is_async_context = async_context;
1082 mono_thread_info_is_async_context (void)
1084 MonoThreadInfo *info = mono_thread_info_current ();
1087 return info->is_async_context;
1094 MonoThreadStart start_routine;
1095 gpointer start_routine_arg;
1097 MonoCoopSem registered;
1098 MonoThreadHandle *handle;
1102 inner_start_thread (gpointer data)
1104 CreateThreadData *thread_data;
1105 MonoThreadInfo *info;
1106 MonoThreadStart start_routine;
1107 gpointer start_routine_arg;
1108 gsize start_routine_res;
1111 thread_data = (CreateThreadData*) data;
1112 g_assert (thread_data);
1114 start_routine = thread_data->start_routine;
1115 start_routine_arg = thread_data->start_routine_arg;
1117 info = mono_thread_info_attach (&dummy);
1118 info->runtime_thread = TRUE;
1120 thread_data->handle = mono_threads_open_thread_handle (info->handle);
1122 mono_coop_sem_post (&thread_data->registered);
1124 if (InterlockedDecrement (&thread_data->ref) == 0) {
1125 mono_coop_sem_destroy (&thread_data->registered);
1126 g_free (thread_data);
1129 /* thread_data is not valid anymore */
1132 /* Run the actual main function of the thread */
1133 start_routine_res = start_routine (start_routine_arg);
1135 mono_thread_info_exit (start_routine_res);
1137 g_assert_not_reached ();
1141 * mono_threads_create_thread:
1143 * Create a new thread executing START with argument ARG. Store its id into OUT_TID.
1144 * Returns: a windows or io-layer handle for the thread.
1147 mono_threads_create_thread (MonoThreadStart start, gpointer arg, gsize * const stack_size, MonoNativeThreadId *out_tid)
1149 CreateThreadData *thread_data;
1151 MonoThreadHandle *ret;
1153 thread_data = g_new0 (CreateThreadData, 1);
1154 thread_data->ref = 2;
1155 thread_data->start_routine = start;
1156 thread_data->start_routine_arg = arg;
1157 mono_coop_sem_init (&thread_data->registered, 0);
1159 res = mono_threads_platform_create_thread (inner_start_thread, (gpointer) thread_data, stack_size, out_tid);
1161 /* ref is not going to be decremented in inner_start_thread */
1162 InterlockedDecrement (&thread_data->ref);
1167 res = mono_coop_sem_wait (&thread_data->registered, MONO_SEM_FLAGS_NONE);
1168 g_assert (res == 0);
1170 ret = thread_data->handle;
1174 if (InterlockedDecrement (&thread_data->ref) == 0) {
1175 mono_coop_sem_destroy (&thread_data->registered);
1176 g_free (thread_data);
1183 * mono_thread_info_get_stack_bounds:
1185 * Return the address and size of the current threads stack. Return NULL as the
1186 * stack address if the stack address cannot be determined.
1189 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize)
1191 guint8 *current = (guint8 *)&stsize;
1192 mono_threads_platform_get_stack_bounds (staddr, stsize);
1196 /* Sanity check the result */
1197 g_assert ((current > *staddr) && (current < *staddr + *stsize));
1199 /* When running under emacs, sometimes staddr is not aligned to a page size */
1200 *staddr = (guint8*)((gssize)*staddr & ~(mono_pagesize () - 1));
1204 mono_thread_info_yield (void)
1206 return mono_threads_platform_yield ();
1208 static mono_lazy_init_t sleep_init = MONO_LAZY_INIT_STATUS_NOT_INITIALIZED;
1209 static MonoCoopMutex sleep_mutex;
1210 static MonoCoopCond sleep_cond;
1213 sleep_initialize (void)
1215 mono_coop_mutex_init (&sleep_mutex);
1216 mono_coop_cond_init (&sleep_cond);
1220 sleep_interrupt (gpointer data)
1222 mono_coop_mutex_lock (&sleep_mutex);
1223 mono_coop_cond_broadcast (&sleep_cond);
1224 mono_coop_mutex_unlock (&sleep_mutex);
1227 static inline guint32
1228 sleep_interruptable (guint32 ms, gboolean *alerted)
1232 g_assert (INFINITE == G_MAXUINT32);
1238 end = mono_msec_ticks() + ms;
1240 mono_lazy_initialize (&sleep_init, sleep_initialize);
1242 mono_coop_mutex_lock (&sleep_mutex);
1245 if (ms != INFINITE) {
1246 now = mono_msec_ticks();
1251 mono_thread_info_install_interrupt (sleep_interrupt, NULL, alerted);
1253 mono_coop_mutex_unlock (&sleep_mutex);
1254 return WAIT_IO_COMPLETION;
1258 mono_coop_cond_timedwait (&sleep_cond, &sleep_mutex, end - now);
1260 mono_coop_cond_wait (&sleep_cond, &sleep_mutex);
1262 mono_thread_info_uninstall_interrupt (alerted);
1264 mono_coop_mutex_unlock (&sleep_mutex);
1265 return WAIT_IO_COMPLETION;
1269 mono_coop_mutex_unlock (&sleep_mutex);
1275 mono_thread_info_sleep (guint32 ms, gboolean *alerted)
1278 MonoThreadInfo *info;
1280 mono_thread_info_yield ();
1282 info = mono_thread_info_current ();
1283 if (info && mono_thread_info_is_interrupt_state (info))
1284 return WAIT_IO_COMPLETION;
1290 return sleep_interruptable (ms, alerted);
1294 if (ms == INFINITE) {
1297 Sleep (G_MAXUINT32);
1299 sleep (G_MAXUINT32);
1304 #if defined (__linux__) && !defined(PLATFORM_ANDROID)
1305 struct timespec start, target;
1307 /* Use clock_nanosleep () to prevent time drifting problems when nanosleep () is interrupted by signals */
1308 ret = clock_gettime (CLOCK_MONOTONIC, &start);
1309 g_assert (ret == 0);
1312 target.tv_sec += ms / 1000;
1313 target.tv_nsec += (ms % 1000) * 1000000;
1314 if (target.tv_nsec > 999999999) {
1315 target.tv_nsec -= 999999999;
1320 ret = clock_nanosleep (CLOCK_MONOTONIC, TIMER_ABSTIME, &target, NULL);
1325 struct timespec req, rem;
1327 req.tv_sec = ms / 1000;
1328 req.tv_nsec = (ms % 1000) * 1000000;
1331 memset (&rem, 0, sizeof (rem));
1332 ret = nanosleep (&req, &rem);
1334 #endif /* __linux__ */
1343 mono_thread_info_usleep (guint64 us)
1352 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key)
1354 return ((MonoThreadInfo*)info)->tls [key];
1358 * mono_threads_info_tls_set:
1360 * Set the TLS key to VALUE in the info structure. This can be used to obtain
1361 * values of TLS variables for threads other than the current thread.
1362 * This should only be used for infrequently changing TLS variables, and it should
1363 * be paired with setting the real TLS variable since this provides no GC tracking.
1366 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value)
1368 ((MonoThreadInfo*)info)->tls [key] = value;
1371 #if defined(__native_client__)
1372 void nacl_shutdown_gc_thread(void);
1376 * mono_thread_info_exit:
1378 * Exit the current thread.
1379 * This function doesn't return.
1382 mono_thread_info_exit (gsize exit_code)
1384 #if defined(__native_client__)
1385 nacl_shutdown_gc_thread();
1388 mono_thread_info_detach ();
1390 mono_threads_platform_exit (0);
1394 * mono_threads_open_thread_handle:
1396 * Duplicate the handle. The handle needs to be closed by calling
1397 * mono_threads_close_thread_handle () when it is no longer needed.
1400 mono_threads_open_thread_handle (MonoThreadHandle *thread_handle)
1402 guint32 oldref, newref;
1404 g_assert (thread_handle);
1407 oldref = thread_handle->ref;
1409 g_error ("%s: thread_handle %p has ref %u, it should be >= 1", __func__, thread_handle, oldref);
1411 newref = oldref + 1;
1412 } while (InterlockedCompareExchange ((gint32*) &thread_handle->ref, newref, oldref) != oldref);
1414 return thread_handle;
1418 mono_threads_close_thread_handle (MonoThreadHandle *thread_handle)
1420 guint32 oldref, newref;
1422 g_assert (thread_handle);
1425 oldref = thread_handle->ref;
1427 g_error ("%s: thread_handle %p has ref %u, it should be >= 1", __func__, thread_handle, oldref);
1429 newref = oldref - 1;
1430 } while (InterlockedCompareExchange ((gint32*) &thread_handle->ref, newref, oldref) != oldref);
1433 mono_os_event_destroy (&thread_handle->event);
1434 g_free (thread_handle);
1439 mono_threads_signal_thread_handle (MonoThreadHandle* thread_handle)
1441 mono_os_event_set (&thread_handle->event);
1444 #define INTERRUPT_STATE ((MonoThreadInfoInterruptToken*) (size_t) -1)
1446 struct _MonoThreadInfoInterruptToken {
1447 void (*callback) (gpointer data);
1452 * mono_thread_info_install_interrupt: install an interruption token for the current thread.
1454 * - @callback: must be able to be called from another thread and always cancel the wait
1455 * - @data: passed to the callback
1456 * - @interrupted: will be set to TRUE if a token is already installed, FALSE otherwise
1457 * if set to TRUE, it must mean that the thread is in interrupted state
1460 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted)
1462 MonoThreadInfo *info;
1463 MonoThreadInfoInterruptToken *previous_token, *token;
1465 g_assert (callback);
1467 g_assert (interrupted);
1468 *interrupted = FALSE;
1470 info = mono_thread_info_current ();
1473 /* The memory of this token can be freed at 2 places:
1474 * - if the token is not interrupted: it will be freed in uninstall, as info->interrupt_token has not been replaced
1475 * by the INTERRUPT_STATE flag value, and it still contains the pointer to the memory location
1476 * - if the token is interrupted: it will be freed in finish, as the token is now owned by the prepare/finish
1477 * functions, and info->interrupt_token does not contains a pointer to the memory anymore */
1478 token = g_new0 (MonoThreadInfoInterruptToken, 1);
1479 token->callback = callback;
1482 previous_token = (MonoThreadInfoInterruptToken *)InterlockedCompareExchangePointer ((gpointer*) &info->interrupt_token, token, NULL);
1484 if (previous_token) {
1485 if (previous_token != INTERRUPT_STATE)
1486 g_error ("mono_thread_info_install_interrupt: previous_token should be INTERRUPT_STATE (%p), but it was %p", INTERRUPT_STATE, previous_token);
1490 *interrupted = TRUE;
1493 THREADS_INTERRUPT_DEBUG ("interrupt install tid %p token %p previous_token %p interrupted %s\n",
1494 mono_thread_info_get_tid (info), token, previous_token, *interrupted ? "TRUE" : "FALSE");
1498 mono_thread_info_uninstall_interrupt (gboolean *interrupted)
1500 MonoThreadInfo *info;
1501 MonoThreadInfoInterruptToken *previous_token;
1503 g_assert (interrupted);
1504 *interrupted = FALSE;
1506 info = mono_thread_info_current ();
1509 previous_token = (MonoThreadInfoInterruptToken *)InterlockedExchangePointer ((gpointer*) &info->interrupt_token, NULL);
1511 /* only the installer can uninstall the token */
1512 g_assert (previous_token);
1514 if (previous_token == INTERRUPT_STATE) {
1515 /* if it is interrupted, then it is going to be freed in finish interrupt */
1516 *interrupted = TRUE;
1518 g_free (previous_token);
1521 THREADS_INTERRUPT_DEBUG ("interrupt uninstall tid %p previous_token %p interrupted %s\n",
1522 mono_thread_info_get_tid (info), previous_token, *interrupted ? "TRUE" : "FALSE");
1525 static MonoThreadInfoInterruptToken*
1526 set_interrupt_state (MonoThreadInfo *info)
1528 MonoThreadInfoInterruptToken *token, *previous_token;
1532 /* Atomically obtain the token the thread is
1533 * waiting on, and change it to a flag value. */
1536 previous_token = info->interrupt_token;
1538 /* Already interrupted */
1539 if (previous_token == INTERRUPT_STATE) {
1544 token = previous_token;
1545 } while (InterlockedCompareExchangePointer ((gpointer*) &info->interrupt_token, INTERRUPT_STATE, previous_token) != previous_token);
1551 * mono_thread_info_prepare_interrupt:
1553 * The state of the thread info interrupt token is set to 'interrupted' which means that :
1554 * - if the thread calls one of the WaitFor functions, the function will return with
1555 * WAIT_IO_COMPLETION instead of waiting
1556 * - if the thread was waiting when this function was called, the wait will be broken
1558 * It is possible that the wait functions return WAIT_IO_COMPLETION, but the target thread
1559 * didn't receive the interrupt signal yet, in this case it should call the wait function
1560 * again. This essentially means that the target thread will busy wait until it is ready to
1561 * process the interruption.
1563 MonoThreadInfoInterruptToken*
1564 mono_thread_info_prepare_interrupt (MonoThreadInfo *info)
1566 MonoThreadInfoInterruptToken *token;
1568 token = set_interrupt_state (info);
1570 THREADS_INTERRUPT_DEBUG ("interrupt prepare tid %p token %p\n",
1571 mono_thread_info_get_tid (info), token);
1577 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token)
1579 THREADS_INTERRUPT_DEBUG ("interrupt finish token %p\n", token);
1584 g_assert (token->callback);
1586 token->callback (token->data);
1592 mono_thread_info_self_interrupt (void)
1594 MonoThreadInfo *info;
1595 MonoThreadInfoInterruptToken *token;
1597 info = mono_thread_info_current ();
1600 token = set_interrupt_state (info);
1603 THREADS_INTERRUPT_DEBUG ("interrupt self tid %p\n",
1604 mono_thread_info_get_tid (info));
1607 /* Clear the interrupted flag of the current thread, set with
1608 * mono_thread_info_self_interrupt, so it can wait again */
1610 mono_thread_info_clear_self_interrupt ()
1612 MonoThreadInfo *info;
1613 MonoThreadInfoInterruptToken *previous_token;
1615 info = mono_thread_info_current ();
1618 previous_token = (MonoThreadInfoInterruptToken *)InterlockedCompareExchangePointer ((gpointer*) &info->interrupt_token, NULL, INTERRUPT_STATE);
1619 g_assert (previous_token == NULL || previous_token == INTERRUPT_STATE);
1621 THREADS_INTERRUPT_DEBUG ("interrupt clear self tid %p previous_token %p\n", mono_thread_info_get_tid (info), previous_token);
1625 mono_thread_info_is_interrupt_state (MonoThreadInfo *info)
1628 return InterlockedReadPointer ((gpointer*) &info->interrupt_token) == INTERRUPT_STATE;
1632 mono_thread_info_describe_interrupt_token (MonoThreadInfo *info, GString *text)
1636 if (!InterlockedReadPointer ((gpointer*) &info->interrupt_token))
1637 g_string_append_printf (text, "not waiting");
1638 else if (InterlockedReadPointer ((gpointer*) &info->interrupt_token) == INTERRUPT_STATE)
1639 g_string_append_printf (text, "interrupted state");
1641 g_string_append_printf (text, "waiting");
1645 mono_thread_info_is_current (MonoThreadInfo *info)
1647 return mono_thread_info_get_tid (info) == mono_native_thread_id_get ();
1650 MonoThreadInfoWaitRet
1651 mono_thread_info_wait_one_handle (MonoThreadHandle *thread_handle, guint32 timeout, gboolean alertable)
1653 MonoOSEventWaitRet res;
1655 res = mono_os_event_wait_one (&thread_handle->event, timeout);
1656 if (res == MONO_OS_EVENT_WAIT_RET_SUCCESS_0)
1657 return MONO_THREAD_INFO_WAIT_RET_SUCCESS_0;
1658 else if (res == MONO_OS_EVENT_WAIT_RET_ALERTED)
1659 return MONO_THREAD_INFO_WAIT_RET_ALERTED;
1660 else if (res == MONO_OS_EVENT_WAIT_RET_TIMEOUT)
1661 return MONO_THREAD_INFO_WAIT_RET_TIMEOUT;
1663 g_error ("%s: unknown res value %d", __func__, res);
1666 MonoThreadInfoWaitRet
1667 mono_thread_info_wait_multiple_handle (MonoThreadHandle **thread_handles, gsize nhandles, MonoOSEvent *background_change_event, gboolean waitall, guint32 timeout, gboolean alertable)
1669 MonoOSEventWaitRet res;
1670 MonoOSEvent *thread_events [MONO_OS_EVENT_WAIT_MAXIMUM_OBJECTS];
1673 g_assert (nhandles <= MONO_OS_EVENT_WAIT_MAXIMUM_OBJECTS);
1674 if (background_change_event)
1675 g_assert (nhandles <= MONO_OS_EVENT_WAIT_MAXIMUM_OBJECTS - 1);
1677 for (i = 0; i < nhandles; ++i)
1678 thread_events [i] = &thread_handles [i]->event;
1680 if (background_change_event)
1681 thread_events [nhandles ++] = background_change_event;
1683 res = mono_os_event_wait_multiple (thread_events, nhandles, waitall, timeout);
1684 if (res >= MONO_OS_EVENT_WAIT_RET_SUCCESS_0 && res <= MONO_OS_EVENT_WAIT_RET_SUCCESS_0 + nhandles - 1)
1685 return MONO_THREAD_INFO_WAIT_RET_SUCCESS_0 + (res - MONO_OS_EVENT_WAIT_RET_SUCCESS_0);
1686 else if (res == MONO_OS_EVENT_WAIT_RET_ALERTED)
1687 return MONO_THREAD_INFO_WAIT_RET_ALERTED;
1688 else if (res == MONO_OS_EVENT_WAIT_RET_TIMEOUT)
1689 return MONO_THREAD_INFO_WAIT_RET_TIMEOUT;
1691 g_error ("%s: unknown res value %d", __func__, res);