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>
18 #include <mono/utils/os-event.h>
20 #include <mono/io-layer/io-layer.h>
28 typedef DWORD MonoNativeThreadId;
29 typedef HANDLE MonoNativeThreadHandle; /* unused */
31 typedef DWORD mono_native_thread_return_t;
33 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (tid)
34 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) ((MonoNativeThreadId)(tid))
36 typedef LPTHREAD_START_ROUTINE MonoThreadStart;
43 #include <mono/utils/mach-support.h>
45 typedef thread_port_t MonoNativeThreadHandle;
51 typedef pid_t MonoNativeThreadHandle;
53 #endif /* defined(__MACH__) */
55 typedef pthread_t MonoNativeThreadId;
57 typedef void* mono_native_thread_return_t;
59 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (gsize)(tid)
60 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) (MonoNativeThreadId)(gsize)(tid)
62 typedef gsize (*MonoThreadStart)(gpointer);
64 #endif /* #ifdef HOST_WIN32 */
72 THREAD_INFO_TYPE is a way to make the mono-threads module parametric - or sort of.
73 The GC using mono-threads might extend the MonoThreadInfo struct to add its own
74 data, this avoid a pointer indirection on what is on a lot of hot paths.
76 But extending MonoThreadInfo has de disavantage that all functions here return type
77 would require a cast, something like the following:
85 ((MyThreadInfo*)mono_thread_info_current ())->stuff = 1;
87 While porting sgen to use mono-threads, the number of casts required was too much and
88 code ended up looking horrible. So we use this cute little hack. The idea is that
89 whomever is including this header can set the expected type to be used by functions here
90 and reduce the number of casts drastically.
93 #ifndef THREAD_INFO_TYPE
94 #define THREAD_INFO_TYPE MonoThreadInfo
97 /* Mono Threads internal configuration knows*/
99 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
100 // #define USE_SIGNALS_ON_MACH
102 #if defined (_POSIX_VERSION) || defined (__native_client__)
103 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
104 #define USE_MACH_BACKEND
106 #define USE_POSIX_BACKEND
109 #define USE_WINDOWS_BACKEND
111 #error "no backend support for current platform"
112 #endif /* defined (_POSIX_VERSION) || defined (__native_client__) */
115 STATE_STARTING = 0x00,
116 STATE_RUNNING = 0x01,
117 STATE_DETACHED = 0x02,
119 STATE_ASYNC_SUSPENDED = 0x03,
120 STATE_SELF_SUSPENDED = 0x04,
121 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
122 STATE_SELF_SUSPEND_REQUESTED = 0x06,
123 STATE_BLOCKING = 0x07,
124 STATE_BLOCKING_AND_SUSPENDED = 0x8,
128 THREAD_STATE_MASK = 0x00FF,
129 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
130 THREAD_SUSPEND_COUNT_SHIFT = 8,
131 THREAD_SUSPEND_COUNT_MAX = 0xFF,
133 SELF_SUSPEND_STATE_INDEX = 0,
134 ASYNC_SUSPEND_STATE_INDEX = 1,
137 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
140 MonoLinkedListSetNode node;
141 guint32 small_id; /*Used by hazard pointers */
142 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
145 /*Tells if this thread was created by the runtime or not.*/
146 gboolean runtime_thread;
148 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
149 gboolean tools_thread;
151 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
152 void *stack_start_limit, *stack_end;
154 /* suspend machinery, fields protected by suspend_semaphore */
155 MonoSemType suspend_semaphore;
158 MonoSemType resume_semaphore;
160 /* only needed by the posix backend */
161 #if defined(USE_POSIX_BACKEND)
162 MonoSemType finish_resume_semaphore;
163 gboolean syscall_break_signal;
167 gboolean suspend_can_continue;
169 /* This memory pool is used by coop GC to save stack data roots between GC unsafe regions */
170 GByteArray *stackdata;
172 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
173 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
175 /*async call machinery, thread MUST be suspended before accessing those fields*/
176 void (*async_target)(void*);
180 If true, this thread is running a critical region of code and cannot be suspended.
181 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
182 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
184 gboolean inside_critical_region;
187 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
188 * operations like locking without having to pass an 'async' parameter around.
190 gboolean is_async_context;
193 * Values of TLS variables for this thread.
194 * This can be used to obtain the values of TLS variable for threads
195 * other than the current one.
197 gpointer tls [TLS_KEY_NUM];
199 /* IO layer handle for this thread */
200 /* Set when the thread is started, or in _wapi_thread_duplicate () */
201 MonoThreadHandle *handle;
205 MonoThreadInfoInterruptToken *interrupt_token;
207 /* HandleStack for coop handles */
208 gpointer handle_stack;
210 /* Stack mark for targets that explicitly require one */
215 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
217 This callback is called with @info still on the thread list.
218 This call is made while holding the suspend lock, so don't do callbacks.
219 SMR remains functional as its small_id has not been reclaimed.
221 void (*thread_unregister)(THREAD_INFO_TYPE *info);
223 This callback is called right before thread_unregister. This is called
224 without any locks held so it's the place for complicated cleanup.
226 The thread must remain operational between this call and thread_unregister.
227 It must be possible to successfully suspend it after thread_unregister completes.
229 void (*thread_detach)(THREAD_INFO_TYPE *info);
230 void (*thread_attach)(THREAD_INFO_TYPE *info);
231 gboolean (*mono_method_is_critical) (void *method);
232 gboolean (*ip_in_critical_region) (MonoDomain *domain, gpointer ip);
233 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
234 } MonoThreadInfoCallbacks;
237 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
238 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
239 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
240 void (*thread_state_init) (MonoThreadUnwindState *tctx);
241 } MonoThreadInfoRuntimeCallbacks;
243 //Not using 0 and 1 to ensure callbacks are not returning bad data
245 MonoResumeThread = 0x1234,
246 KeepSuspended = 0x4321,
247 } SuspendThreadResult;
249 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
251 static inline gboolean
252 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
254 return !((MonoThreadInfo*)info)->tools_thread;
258 Requires the world to be stoped
260 #define FOREACH_THREAD(thread) \
261 MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
263 #define FOREACH_THREAD_END \
269 #define FOREACH_THREAD_SAFE(thread) \
270 MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
272 #define FOREACH_THREAD_SAFE_END \
273 MONO_LLS_FOREACH_SAFE_END
275 static inline MonoNativeThreadId
276 mono_thread_info_get_tid (THREAD_INFO_TYPE *info)
278 return MONO_UINT_TO_NATIVE_THREAD_ID (((MonoThreadInfo*) info)->node.key);
282 mono_thread_info_set_tid (THREAD_INFO_TYPE *info, MonoNativeThreadId tid)
284 ((MonoThreadInfo*) info)->node.key = (uintptr_t) MONO_NATIVE_THREAD_ID_TO_UINT (tid);
288 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
289 * a single block with info from both camps.
292 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
295 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
297 MonoThreadInfoRuntimeCallbacks *
298 mono_threads_get_runtime_callbacks (void);
301 mono_thread_info_register_small_id (void);
304 mono_thread_info_attach (void *baseptr);
307 mono_thread_info_detach (void);
310 mono_thread_info_is_exiting (void);
313 mono_thread_info_current (void);
316 mono_thread_info_current_unchecked (void);
319 mono_thread_info_get_small_id (void);
322 mono_thread_info_list_head (void);
325 mono_thread_info_lookup (MonoNativeThreadId id);
328 mono_thread_info_resume (MonoNativeThreadId tid);
331 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
334 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
337 mono_thread_info_suspend_lock (void);
340 mono_thread_info_suspend_unlock (void);
343 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
346 mono_thread_info_set_is_async_context (gboolean async_context);
349 mono_thread_info_is_async_context (void);
352 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
355 mono_thread_info_yield (void);
358 mono_thread_info_sleep (guint32 ms, gboolean *alerted);
361 mono_thread_info_usleep (guint64 us);
364 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
367 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
370 mono_thread_info_exit (gsize exit_code);
373 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
376 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
378 MonoThreadInfoInterruptToken*
379 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
382 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
385 mono_thread_info_self_interrupt (void);
388 mono_thread_info_clear_self_interrupt (void);
391 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
394 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
397 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
400 mono_threads_create_thread (MonoThreadStart start, gpointer arg, gsize * const stack_size, MonoNativeThreadId *out_tid);
403 mono_threads_get_max_stack_size (void);
406 mono_threads_open_thread_handle (MonoThreadHandle *handle);
409 mono_threads_close_thread_handle (MonoThreadHandle *handle);
412 mono_threads_attach_tools_thread (void);
415 #if !defined(HOST_WIN32)
417 /*Use this instead of pthread_kill */
419 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
421 #endif /* !defined(HOST_WIN32) */
423 /* Internal API between mono-threads and its backends. */
425 /* Backend functions - a backend must implement all of the following */
427 This is called very early in the runtime, it cannot access any runtime facilities.
430 void mono_threads_suspend_init (void); //ok
432 void mono_threads_suspend_init_signals (void);
434 void mono_threads_coop_init (void);
437 This begins async suspend. This function must do the following:
439 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
440 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
441 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
443 If begin suspend fails the thread must be left uninterrupted and resumed.
445 gboolean mono_threads_suspend_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
448 This verifies the outcome of an async suspend operation.
450 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
451 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
453 gboolean mono_threads_suspend_check_suspend_result (THREAD_INFO_TYPE *info);
456 This begins async resume. This function must do the following:
458 - Install an async target if one was requested.
459 - Notify the target to resume.
460 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
462 gboolean mono_threads_suspend_begin_async_resume (THREAD_INFO_TYPE *info);
464 void mono_threads_suspend_register (THREAD_INFO_TYPE *info); //ok
465 void mono_threads_suspend_free (THREAD_INFO_TYPE *info);
466 void mono_threads_suspend_abort_syscall (THREAD_INFO_TYPE *info);
467 gboolean mono_threads_suspend_needs_abort_syscall (void);
468 gint mono_threads_suspend_search_alternative_signal (void);
469 gint mono_threads_suspend_get_suspend_signal (void);
470 gint mono_threads_suspend_get_restart_signal (void);
471 gint mono_threads_suspend_get_abort_signal (void);
473 int mono_threads_platform_create_thread (MonoThreadStart thread_fn, gpointer thread_data, gsize* const stack_size, MonoNativeThreadId *out_tid);
474 void mono_threads_platform_get_stack_bounds (guint8 **staddr, size_t *stsize);
475 gboolean mono_threads_platform_yield (void);
476 void mono_threads_platform_exit (gsize exit_code);
478 void mono_threads_coop_begin_global_suspend (void);
479 void mono_threads_coop_end_global_suspend (void);
481 MONO_API MonoNativeThreadId
482 mono_native_thread_id_get (void);
485 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
488 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
491 mono_native_thread_set_name (MonoNativeThreadId tid, const char *name);
494 mono_native_thread_join (MonoNativeThreadId tid);
496 /*Mach specific internals */
497 void mono_threads_init_dead_letter (void);
498 void mono_threads_install_dead_letter (void);
500 /* mono-threads internal API used by the backends. */
502 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
504 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
506 This tells the resume initiator that we completed resume duties and will return to runnable state.
508 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
511 This tells the resume initiator that we completed abort duties and will return to previous state.
513 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
515 /* Thread state machine functions */
520 ResumeInitSelfResume,
521 ResumeInitAsyncResume,
522 ResumeInitBlockingResume,
528 SelfSuspendNotifyAndWait,
529 } MonoSelfSupendResult;
532 AsyncSuspendAlreadySuspended,
534 AsyncSuspendInitSuspend,
535 AsyncSuspendBlocking,
536 } MonoRequestAsyncSuspendResult;
539 DoBlockingContinue, //in blocking mode, continue
540 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
541 } MonoDoBlockingResult;
544 DoneBlockingOk, //exited blocking fine
545 DoneBlockingWait, //thread should end suspended
546 } MonoDoneBlockingResult;
550 AbortBlockingIgnore, //Ignore
551 AbortBlockingIgnoreAndPoll, //Ignore and poll
552 AbortBlockingOk, //Abort worked
553 AbortBlockingWait, //Abort worked, but should wait for resume
554 } MonoAbortBlockingResult;
557 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
558 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
559 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
560 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
561 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
562 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
563 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
564 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
565 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
567 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
570 mono_threads_enter_gc_unsafe_region_cookie (void);
573 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
574 /* Advanced suspend API, used for suspending multiple threads as once. */
575 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
576 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
577 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
578 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
579 const char* mono_thread_state_name (int state);
581 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
582 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
583 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
585 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
586 gboolean mono_threads_wait_pending_operations (void);
587 void mono_threads_begin_global_suspend (void);
588 void mono_threads_end_global_suspend (void);
591 mono_thread_info_is_current (THREAD_INFO_TYPE *info);
594 MONO_THREAD_INFO_WAIT_RET_SUCCESS_0 = 0,
595 MONO_THREAD_INFO_WAIT_RET_ALERTED = -1,
596 MONO_THREAD_INFO_WAIT_RET_TIMEOUT = -2,
597 MONO_THREAD_INFO_WAIT_RET_FAILED = -3,
598 } MonoThreadInfoWaitRet;
600 MonoThreadInfoWaitRet
601 mono_thread_info_wait_one_handle (MonoThreadHandle *handle, guint32 timeout, gboolean alertable);
603 MonoThreadInfoWaitRet
604 mono_thread_info_wait_multiple_handle (MonoThreadHandle **thread_handles, gsize nhandles, MonoOSEvent *background_change_event, gboolean waitall, guint32 timeout, gboolean alertable);
606 #endif /* __MONO_THREADS_H__ */