2 * mono-threads.h: Low-level threading
5 * Rodrigo Kumpera (kumpera@gmail.com)
10 #ifndef __MONO_THREADS_H__
11 #define __MONO_THREADS_H__
13 #include <mono/utils/mono-os-semaphore.h>
14 #include <mono/utils/mono-stack-unwinding.h>
15 #include <mono/utils/mono-linked-list-set.h>
16 #include <mono/utils/mono-tls.h>
17 #include <mono/utils/mono-coop-semaphore.h>
19 #include <mono/io-layer/io-layer.h>
27 typedef DWORD MonoNativeThreadId;
28 typedef HANDLE MonoNativeThreadHandle; /* unused */
30 typedef DWORD mono_native_thread_return_t;
32 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (tid)
33 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) ((MonoNativeThreadId)(tid))
35 typedef LPTHREAD_START_ROUTINE MonoThreadStart;
42 #include <mono/utils/mach-support.h>
44 typedef thread_port_t MonoNativeThreadHandle;
50 typedef pid_t MonoNativeThreadHandle;
52 #endif /* defined(__MACH__) */
54 typedef pthread_t MonoNativeThreadId;
56 typedef void* mono_native_thread_return_t;
58 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (gsize)(tid)
59 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) (MonoNativeThreadId)(gsize)(tid)
61 typedef gsize (*MonoThreadStart)(gpointer);
63 #endif /* #ifdef HOST_WIN32 */
66 THREAD_INFO_TYPE is a way to make the mono-threads module parametric - or sort of.
67 The GC using mono-threads might extend the MonoThreadInfo struct to add its own
68 data, this avoid a pointer indirection on what is on a lot of hot paths.
70 But extending MonoThreadInfo has de disavantage that all functions here return type
71 would require a cast, something like the following:
79 ((MyThreadInfo*)mono_thread_info_current ())->stuff = 1;
81 While porting sgen to use mono-threads, the number of casts required was too much and
82 code ended up looking horrible. So we use this cute little hack. The idea is that
83 whomever is including this header can set the expected type to be used by functions here
84 and reduce the number of casts drastically.
87 #ifndef THREAD_INFO_TYPE
88 #define THREAD_INFO_TYPE MonoThreadInfo
91 /* Mono Threads internal configuration knows*/
93 /* Logging - enable them below if you need specific logging for the category you need */
94 #define MOSTLY_ASYNC_SAFE_PRINTF(...) do { \
95 char __buff[1024]; __buff [0] = '\0'; \
96 g_snprintf (__buff, sizeof (__buff), __VA_ARGS__); \
97 write (1, __buff, strlen (__buff)); \
102 #define THREADS_DEBUG(...)
104 #define THREADS_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
108 #define THREADS_STW_DEBUG(...)
110 #define THREADS_STW_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
114 #define THREADS_SUSPEND_DEBUG(...)
116 #define THREADS_SUSPEND_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
120 #define THREADS_STATE_MACHINE_DEBUG(...)
122 #define THREADS_STATE_MACHINE_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
126 #define THREADS_INTERRUPT_DEBUG(...)
128 #define THREADS_INTERRUPT_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
131 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
132 // #define USE_SIGNALS_ON_MACH
134 #if defined (_POSIX_VERSION) || defined (__native_client__)
135 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
136 #define USE_MACH_BACKEND
138 #define USE_POSIX_BACKEND
141 #define USE_WINDOWS_BACKEND
143 #error "no backend support for current platform"
144 #endif /* defined (_POSIX_VERSION) || defined (__native_client__) */
147 STATE_STARTING = 0x00,
148 STATE_RUNNING = 0x01,
149 STATE_DETACHED = 0x02,
151 STATE_ASYNC_SUSPENDED = 0x03,
152 STATE_SELF_SUSPENDED = 0x04,
153 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
154 STATE_SELF_SUSPEND_REQUESTED = 0x06,
155 STATE_BLOCKING = 0x07,
156 STATE_BLOCKING_AND_SUSPENDED = 0x8,
160 THREAD_STATE_MASK = 0x00FF,
161 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
162 THREAD_SUSPEND_COUNT_SHIFT = 8,
163 THREAD_SUSPEND_COUNT_MAX = 0xFF,
165 SELF_SUSPEND_STATE_INDEX = 0,
166 ASYNC_SUSPEND_STATE_INDEX = 1,
169 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
172 MonoLinkedListSetNode node;
173 guint32 small_id; /*Used by hazard pointers */
174 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
177 /*Tells if this thread was created by the runtime or not.*/
178 gboolean runtime_thread;
180 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
181 gboolean tools_thread;
183 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
184 void *stack_start_limit, *stack_end;
186 /* suspend machinery, fields protected by suspend_semaphore */
187 MonoSemType suspend_semaphore;
190 MonoSemType resume_semaphore;
192 /* only needed by the posix backend */
193 #if defined(USE_POSIX_BACKEND)
194 MonoSemType finish_resume_semaphore;
195 gboolean syscall_break_signal;
199 gboolean suspend_can_continue;
201 /* This memory pool is used by coop GC to save stack data roots between GC unsafe regions */
202 GByteArray *stackdata;
204 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
205 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
207 /*async call machinery, thread MUST be suspended before accessing those fields*/
208 void (*async_target)(void*);
212 If true, this thread is running a critical region of code and cannot be suspended.
213 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
214 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
216 gboolean inside_critical_region;
219 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
220 * operations like locking without having to pass an 'async' parameter around.
222 gboolean is_async_context;
224 gboolean create_suspended;
226 /* Semaphore used to implement CREATE_SUSPENDED */
227 MonoCoopSem create_suspended_sem;
230 * Values of TLS variables for this thread.
231 * This can be used to obtain the values of TLS variable for threads
232 * other than the current one.
234 gpointer tls [TLS_KEY_NUM];
236 /* IO layer handle for this thread */
237 /* Set when the thread is started, or in _wapi_thread_duplicate () */
242 MonoThreadInfoInterruptToken *interrupt_token;
244 /* HandleStack for coop handles */
245 gpointer handle_stack;
247 /* Stack mark for targets that explicitly require one */
252 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
254 This callback is called with @info still on the thread list.
255 This call is made while holding the suspend lock, so don't do callbacks.
256 SMR remains functional as its small_id has not been reclaimed.
258 void (*thread_unregister)(THREAD_INFO_TYPE *info);
260 This callback is called right before thread_unregister. This is called
261 without any locks held so it's the place for complicated cleanup.
263 The thread must remain operational between this call and thread_unregister.
264 It must be possible to successfully suspend it after thread_unregister completes.
266 void (*thread_detach)(THREAD_INFO_TYPE *info);
267 void (*thread_attach)(THREAD_INFO_TYPE *info);
268 gboolean (*mono_method_is_critical) (void *method);
269 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
270 } MonoThreadInfoCallbacks;
273 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
274 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
275 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
276 void (*thread_state_init) (MonoThreadUnwindState *tctx);
277 } MonoThreadInfoRuntimeCallbacks;
279 //Not using 0 and 1 to ensure callbacks are not returning bad data
281 MonoResumeThread = 0x1234,
282 KeepSuspended = 0x4321,
283 } SuspendThreadResult;
285 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
288 * Parameters to pass for thread creation
292 guint32 creation_flags;
297 MONO_THREAD_PRIORITY_LOWEST = 0,
298 MONO_THREAD_PRIORITY_BELOW_NORMAL = 1,
299 MONO_THREAD_PRIORITY_NORMAL = 2,
300 MONO_THREAD_PRIORITY_ABOVE_NORMAL = 3,
301 MONO_THREAD_PRIORITY_HIGHEST = 4,
302 } MonoThreadPriority;
304 static inline gboolean
305 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
307 return !((MonoThreadInfo*)info)->tools_thread;
311 Requires the world to be stoped
313 #define FOREACH_THREAD(thread) \
314 MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
316 #define FOREACH_THREAD_END \
322 #define FOREACH_THREAD_SAFE(thread) \
323 MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
325 #define FOREACH_THREAD_SAFE_END \
326 MONO_LLS_FOREACH_SAFE_END
328 static inline MonoNativeThreadId
329 mono_thread_info_get_tid (THREAD_INFO_TYPE *info)
331 return MONO_UINT_TO_NATIVE_THREAD_ID (((MonoThreadInfo*) info)->node.key);
335 mono_thread_info_set_tid (THREAD_INFO_TYPE *info, MonoNativeThreadId tid)
337 ((MonoThreadInfo*) info)->node.key = (uintptr_t) MONO_NATIVE_THREAD_ID_TO_UINT (tid);
341 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
342 * a single block with info from both camps.
345 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
348 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
350 MonoThreadInfoRuntimeCallbacks *
351 mono_threads_get_runtime_callbacks (void);
354 mono_thread_info_register_small_id (void);
357 mono_thread_info_attach (void *baseptr);
360 mono_thread_info_detach (void);
363 mono_thread_info_is_exiting (void);
366 mono_thread_info_current (void);
369 mono_thread_info_current_unchecked (void);
372 mono_thread_info_get_small_id (void);
375 mono_thread_info_list_head (void);
378 mono_thread_info_lookup (MonoNativeThreadId id);
381 mono_thread_info_resume (MonoNativeThreadId tid);
384 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
386 //XXX new API, fix the world
388 mono_thread_info_begin_self_suspend (void);
391 mono_thread_info_end_self_suspend (void);
396 mono_thread_info_unified_management_enabled (void);
399 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
402 mono_thread_info_suspend_lock (void);
405 mono_thread_info_suspend_unlock (void);
408 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
411 mono_thread_info_set_is_async_context (gboolean async_context);
414 mono_thread_info_is_async_context (void);
417 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
420 mono_thread_info_yield (void);
423 mono_thread_info_sleep (guint32 ms, gboolean *alerted);
426 mono_thread_info_usleep (guint64 us);
429 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
432 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
435 mono_thread_info_exit (void);
438 mono_thread_info_set_exited (THREAD_INFO_TYPE *info);
441 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
444 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
446 MonoThreadInfoInterruptToken*
447 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
450 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
453 mono_thread_info_self_interrupt (void);
456 mono_thread_info_clear_self_interrupt (void);
459 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
462 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
465 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
468 mono_threads_create_thread (MonoThreadStart start, gpointer arg, MonoThreadParm *tp, MonoNativeThreadId *out_tid);
471 mono_threads_get_max_stack_size (void);
474 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
477 mono_threads_attach_tools_thread (void);
480 #if !defined(HOST_WIN32)
482 /*Use this instead of pthread_kill */
484 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
486 #endif /* !defined(HOST_WIN32) */
488 /* Internal API between mono-threads and its backends. */
490 /* Backend functions - a backend must implement all of the following */
492 This is called very early in the runtime, it cannot access any runtime facilities.
495 void mono_threads_suspend_init (void); //ok
497 void mono_threads_platform_init (void);
499 void mono_threads_coop_init (void);
501 void mono_threads_abort_syscall_init (void);
504 This begins async suspend. This function must do the following:
506 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
507 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
508 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
510 If begin suspend fails the thread must be left uninterrupted and resumed.
512 gboolean mono_threads_suspend_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
515 This verifies the outcome of an async suspend operation.
517 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
518 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
520 gboolean mono_threads_suspend_check_suspend_result (THREAD_INFO_TYPE *info);
523 This begins async resume. This function must do the following:
525 - Install an async target if one was requested.
526 - Notify the target to resume.
527 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
529 gboolean mono_threads_suspend_begin_async_resume (THREAD_INFO_TYPE *info);
531 void mono_threads_suspend_register (THREAD_INFO_TYPE *info); //ok
532 void mono_threads_suspend_free (THREAD_INFO_TYPE *info);
533 void mono_threads_suspend_abort_syscall (THREAD_INFO_TYPE *info);
534 gboolean mono_threads_suspend_needs_abort_syscall (void);
536 void mono_threads_platform_register (THREAD_INFO_TYPE *info);
537 void mono_threads_platform_unregister (THREAD_INFO_TYPE *info);
538 HANDLE mono_threads_platform_create_thread (MonoThreadStart start, gpointer arg, MonoThreadParm *, MonoNativeThreadId *out_tid);
539 void mono_threads_platform_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
540 void mono_threads_platform_get_stack_bounds (guint8 **staddr, size_t *stsize);
541 gboolean mono_threads_platform_yield (void);
542 void mono_threads_platform_exit (int exit_code);
543 HANDLE mono_threads_platform_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
544 void mono_threads_platform_set_exited (THREAD_INFO_TYPE *info);
545 void mono_threads_platform_describe (THREAD_INFO_TYPE *info, GString *text);
546 void mono_threads_platform_own_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
547 void mono_threads_platform_disown_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
548 MonoThreadPriority mono_threads_platform_get_priority (THREAD_INFO_TYPE *info);
549 gboolean mono_threads_platform_set_priority (THREAD_INFO_TYPE *info, MonoThreadPriority priority);
551 void mono_threads_coop_begin_global_suspend (void);
552 void mono_threads_coop_end_global_suspend (void);
554 MONO_API MonoNativeThreadId
555 mono_native_thread_id_get (void);
558 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
561 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
564 mono_native_thread_set_name (MonoNativeThreadId tid, const char *name);
566 /*Mach specific internals */
567 void mono_threads_init_dead_letter (void);
568 void mono_threads_install_dead_letter (void);
570 /* mono-threads internal API used by the backends. */
572 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
574 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
576 This tells the resume initiator that we completed resume duties and will return to runnable state.
578 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
581 This tells the resume initiator that we completed abort duties and will return to previous state.
583 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
585 /* Thread state machine functions */
590 ResumeInitSelfResume,
591 ResumeInitAsyncResume,
592 ResumeInitBlockingResume,
598 SelfSuspendNotifyAndWait,
599 } MonoSelfSupendResult;
602 AsyncSuspendAlreadySuspended,
604 AsyncSuspendInitSuspend,
605 AsyncSuspendBlocking,
606 } MonoRequestAsyncSuspendResult;
609 DoBlockingContinue, //in blocking mode, continue
610 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
611 } MonoDoBlockingResult;
614 DoneBlockingOk, //exited blocking fine
615 DoneBlockingWait, //thread should end suspended
616 } MonoDoneBlockingResult;
620 AbortBlockingIgnore, //Ignore
621 AbortBlockingIgnoreAndPoll, //Ignore and poll
622 AbortBlockingOk, //Abort worked
623 AbortBlockingWait, //Abort worked, but should wait for resume
624 } MonoAbortBlockingResult;
627 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
628 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
629 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
630 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
631 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
632 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
633 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
634 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
635 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
636 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
638 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
641 mono_threads_enter_gc_unsafe_region_cookie (void);
644 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
645 /* Advanced suspend API, used for suspending multiple threads as once. */
646 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
647 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
648 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
649 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
650 const char* mono_thread_state_name (int state);
652 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
653 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
654 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
656 void mono_threads_add_to_pending_operation_set (THREAD_INFO_TYPE* info); //XXX rename to something to reflect the fact that this is used for both suspend and resume
657 gboolean mono_threads_wait_pending_operations (void);
658 void mono_threads_begin_global_suspend (void);
659 void mono_threads_end_global_suspend (void);
662 mono_thread_info_is_current (THREAD_INFO_TYPE *info);
665 mono_thread_info_get_handle (THREAD_INFO_TYPE *info);
668 mono_thread_info_describe (THREAD_INFO_TYPE *info, GString *text);
671 mono_thread_info_own_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
674 mono_thread_info_disown_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
677 mono_thread_info_get_priority (THREAD_INFO_TYPE *info);
680 mono_thread_info_set_priority (THREAD_INFO_TYPE *info, MonoThreadPriority priority);
682 #endif /* __MONO_THREADS_H__ */