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-semaphore.h>
14 #include <mono/utils/mono-stack-unwinding.h>
15 #include <mono/utils/mono-linked-list-set.h>
16 #include <mono/utils/mono-mutex.h>
17 #include <mono/utils/mono-tls.h>
25 typedef DWORD MonoNativeThreadId;
26 typedef HANDLE MonoNativeThreadHandle; /* unused */
28 typedef DWORD mono_native_thread_return_t;
30 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (tid)
31 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) ((MonoNativeThreadId)(tid))
38 #include <mono/utils/mach-support.h>
40 typedef thread_port_t MonoNativeThreadHandle;
46 typedef pid_t MonoNativeThreadHandle;
48 #endif /* defined(__MACH__) */
50 typedef pthread_t MonoNativeThreadId;
52 typedef void* mono_native_thread_return_t;
54 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (gsize)(tid)
55 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) (MonoNativeThreadId)(gsize)(tid)
57 #endif /* #ifdef HOST_WIN32 */
60 THREAD_INFO_TYPE is a way to make the mono-threads module parametric - or sort of.
61 The GC using mono-threads might extend the MonoThreadInfo struct to add its own
62 data, this avoid a pointer indirection on what is on a lot of hot paths.
64 But extending MonoThreadInfo has de disavantage that all functions here return type
65 would require a cast, something like the following:
73 ((MyThreadInfo*)mono_thread_info_current ())->stuff = 1;
75 While porting sgen to use mono-threads, the number of casts required was too much and
76 code ended up looking horrible. So we use this cute little hack. The idea is that
77 whomever is including this header can set the expected type to be used by functions here
78 and reduce the number of casts drastically.
81 #ifndef THREAD_INFO_TYPE
82 #define THREAD_INFO_TYPE MonoThreadInfo
85 /* Mono Threads internal configuration knows*/
87 /* Logging - enable them below if you need specific logging for the category you need */
88 #define MOSTLY_ASYNC_SAFE_PRINTF(...) do { \
89 char __buff[1024]; __buff [0] = '\0'; \
90 snprintf (__buff, sizeof (__buff), __VA_ARGS__); \
91 write (1, __buff, strlen (__buff)); \
96 #define THREADS_DEBUG(...)
98 #define THREADS_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
102 #define THREADS_STW_DEBUG(...)
104 #define THREADS_STW_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
108 #define THREADS_SUSPEND_DEBUG(...)
110 #define THREADS_SUSPEND_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
114 #define THREADS_STATE_MACHINE_DEBUG(...)
116 #define THREADS_STATE_MACHINE_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
119 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
120 // #define USE_SIGNALS_ON_MACH
122 #if defined (_POSIX_VERSION) || defined (__native_client__)
123 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
124 #define USE_MACH_BACKEND
126 #define USE_POSIX_BACKEND
132 STATE_STARTING = 0x00,
133 STATE_RUNNING = 0x01,
134 STATE_DETACHED = 0x02,
136 STATE_ASYNC_SUSPENDED = 0x03,
137 STATE_SELF_SUSPENDED = 0x04,
138 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
139 STATE_SELF_SUSPEND_REQUESTED = 0x06,
140 // STATE_SUSPEND_IN_PROGRESS = 0x07,
141 // STATE_SUSPEND_PROMOTED_TO_ASYNC = 0x08,
144 THREAD_STATE_MASK = 0x00FF,
145 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
146 THREAD_SUSPEND_COUNT_SHIFT = 8,
147 THREAD_SUSPEND_COUNT_MAX = 0xFF,
149 SELF_SUSPEND_STATE_INDEX = 0,
150 ASYNC_SUSPEND_STATE_INDEX = 1,
154 * This enum tells which async thread service corresponds to which bit.
157 MONO_SERVICE_REQUEST_SAMPLE = 1,
161 MonoLinkedListSetNode node;
162 guint32 small_id; /*Used by hazard pointers */
163 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
166 /*Tells if this thread was created by the runtime or not.*/
167 gboolean runtime_thread;
169 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
170 gboolean tools_thread;
172 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
173 void *stack_start_limit, *stack_end;
175 /* suspend machinery, fields protected by suspend_semaphore */
176 MonoSemType suspend_semaphore;
179 // MonoSemType suspend_semaphore;
180 MonoSemType resume_semaphore;
182 /* only needed by the posix backend */
183 #if defined(USE_POSIX_BACKEND)
184 MonoSemType finish_resume_semaphore;
185 gboolean syscall_break_signal;
186 gboolean suspend_can_continue;
191 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
192 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
194 /*async call machinery, thread MUST be suspended before accessing those fields*/
195 void (*async_target)(void*);
199 If true, this thread is running a critical region of code and cannot be suspended.
200 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
201 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
203 gboolean inside_critical_region;
206 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
207 * operations like locking without having to pass an 'async' parameter around.
209 gboolean is_async_context;
211 gboolean create_suspended;
213 /* Semaphore used to implement CREATE_SUSPENDED */
214 MonoSemType create_suspended_sem;
217 * Values of TLS variables for this thread.
218 * This can be used to obtain the values of TLS variable for threads
219 * other than the current one.
221 gpointer tls [TLS_KEY_NUM];
223 /* IO layer handle for this thread */
224 /* Set when the thread is started, or in _wapi_thread_duplicate () */
227 /* Asynchronous service request. This flag is meant to be consumed by the multiplexing signal handlers to discover what sort of work they need to do.
228 * Use the mono_threads_add_async_job and mono_threads_consume_async_jobs APIs to modify this flag.
229 * In the future the signaling should be part of the API, but for now, it's only for massaging the bits.
231 volatile gint32 service_requests;
235 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
237 This callback is called with @info still on the thread list.
238 This call is made while holding the suspend lock, so don't do callbacks.
239 SMR remains functional as its small_id has not been reclaimed.
241 void (*thread_unregister)(THREAD_INFO_TYPE *info);
243 This callback is called right before thread_unregister. This is called
244 without any locks held so it's the place for complicated cleanup.
246 The thread must remain operational between this call and thread_unregister.
247 It must be possible to successfully suspend it after thread_unregister completes.
249 void (*thread_detach)(THREAD_INFO_TYPE *info);
250 void (*thread_attach)(THREAD_INFO_TYPE *info);
251 gboolean (*mono_method_is_critical) (void *method);
252 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
253 void (*thread_exit)(void *retval);
255 int (*mono_gc_pthread_create) (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg);
257 } MonoThreadInfoCallbacks;
260 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
261 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
262 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
263 } MonoThreadInfoRuntimeCallbacks;
265 //Not using 0 and 1 to ensure callbacks are not returning bad data
267 ResumeThread = 0x1234,
268 KeepSuspended = 0x4321,
269 } SuspendThreadResult;
271 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
273 static inline gboolean
274 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
276 return !((MonoThreadInfo*)info)->tools_thread;
280 Requires the world to be stoped
282 #define FOREACH_THREAD(thread) MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), thread, mono_threads_filter_tools_threads, THREAD_INFO_TYPE*)
283 #define END_FOREACH_THREAD MONO_LLS_END_FOREACH
288 #define FOREACH_THREAD_SAFE(thread) MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), thread, mono_threads_filter_tools_threads, THREAD_INFO_TYPE*)
289 #define END_FOREACH_THREAD_SAFE MONO_LLS_END_FOREACH_SAFE
291 #define mono_thread_info_get_tid(info) ((MonoNativeThreadId)((MonoThreadInfo*)info)->node.key)
292 #define mono_thread_info_set_tid(info, val) do { ((MonoThreadInfo*)(info))->node.key = (uintptr_t)(val); } while (0)
295 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
296 * a single block with info from both camps.
299 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
302 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
304 MonoThreadInfoCallbacks *
305 mono_threads_get_callbacks (void);
307 MonoThreadInfoRuntimeCallbacks *
308 mono_threads_get_runtime_callbacks (void);
311 mono_thread_info_register_small_id (void);
314 mono_thread_info_attach (void *baseptr);
317 mono_thread_info_detach (void);
320 mono_thread_info_is_exiting (void);
323 mono_thread_info_current (void);
326 mono_thread_info_get_small_id (void);
329 mono_thread_info_list_head (void);
332 mono_thread_info_lookup (MonoNativeThreadId id);
335 mono_thread_info_safe_suspend_sync (MonoNativeThreadId tid, gboolean interrupt_kernel);
338 mono_thread_info_resume (MonoNativeThreadId tid);
341 mono_thread_info_set_name (MonoNativeThreadId tid, const char *name);
344 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
346 //XXX new API, fix the world
348 mono_thread_info_begin_self_suspend (void);
351 mono_thread_info_end_self_suspend (void);
356 mono_thread_info_new_interrupt_enabled (void);
359 mono_thread_info_unified_management_enabled (void);
362 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
365 mono_thread_info_suspend_lock (void);
368 mono_thread_info_suspend_unlock (void);
371 mono_thread_info_disable_new_interrupt (gboolean disable);
374 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
377 mono_thread_info_set_is_async_context (gboolean async_context);
380 mono_thread_info_is_async_context (void);
383 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
386 mono_thread_info_yield (void);
389 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
392 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
395 mono_thread_info_exit (void);
398 mono_thread_info_open_handle (void);
401 mono_thread_info_prepare_interrupt (HANDLE thread_handle);
404 mono_thread_info_finish_interrupt (gpointer wait_handle);
407 mono_thread_info_interrupt (HANDLE thread_handle);
410 mono_thread_info_self_interrupt (void);
413 mono_thread_info_clear_interruption (void);
416 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
419 mono_threads_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
422 mono_threads_get_max_stack_size (void);
425 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
428 This is the async job submission/consumption API.
429 XXX: This is a PROVISIONAL API only meant to be used by the statistical profiler.
430 If you want to use/extend it anywhere else, understand that you'll have to do some API design work to better fit this puppy.
433 mono_threads_add_async_job (THREAD_INFO_TYPE *info, MonoAsyncJob job);
436 mono_threads_consume_async_jobs (void);
439 mono_threads_attach_tools_thread (void);
442 #if !defined(HOST_WIN32)
444 /*Use this instead of pthread_kill */
446 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
448 #endif /* !defined(HOST_WIN32) */
450 /* Plartform specific functions DON'T use them */
451 void mono_threads_init_platform (void); //ok
452 gboolean mono_threads_core_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
453 gboolean mono_threads_core_resume (THREAD_INFO_TYPE *info);
454 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
455 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
456 void mono_threads_core_interrupt (THREAD_INFO_TYPE *info);
457 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
458 gboolean mono_threads_core_needs_abort_syscall (void);
459 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
460 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
461 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
462 gboolean mono_threads_core_yield (void);
463 void mono_threads_core_exit (int exit_code);
464 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
465 HANDLE mono_threads_core_open_handle (void);
466 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
467 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
469 /* Internal API between mono-threads and its backends. */
471 /* Backend functions - a backend must implement all of the following */
473 This is called very early in the runtime, it cannot access any runtime facilities.
476 void mono_threads_init_platform (void); //ok
479 This begins async suspend. This function must do the following:
481 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
482 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
483 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
485 If begin suspend fails the thread must be left uninterrupted and resumed.
487 gboolean mono_threads_core_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
490 This verifies the outcome of an async suspend operation.
492 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
493 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
495 gboolean mono_threads_core_check_suspend_result (THREAD_INFO_TYPE *info);
498 This begins async resume. This function must do the following:
500 - Install an async target if one was requested.
501 - Notify the target to resume.
502 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
504 gboolean mono_threads_core_begin_async_resume (THREAD_INFO_TYPE *info);
506 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
507 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
508 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
509 gboolean mono_threads_core_needs_abort_syscall (void);
510 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
511 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
512 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
513 gboolean mono_threads_core_yield (void);
514 void mono_threads_core_exit (int exit_code);
515 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
516 HANDLE mono_threads_core_open_handle (void);
517 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
518 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
519 gpointer mono_threads_core_prepare_interrupt (HANDLE thread_handle);
520 void mono_threads_core_finish_interrupt (gpointer wait_handle);
521 void mono_threads_core_self_interrupt (void);
522 void mono_threads_core_clear_interruption (void);
524 MonoNativeThreadId mono_native_thread_id_get (void);
526 gboolean mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
529 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
531 /*Mach specific internals */
532 void mono_threads_init_dead_letter (void);
533 void mono_threads_install_dead_letter (void);
535 /* mono-threads internal API used by the backends. */
537 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
539 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
541 This tells the resume initiator that we completed resume duties and will return to runnable state.
543 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
545 /* Thread state machine functions */
550 ResumeInitSelfResume,
551 ResumeInitAsyncResume,
557 SelfSuspendNotifyAndWait,
558 } MonoSelfSupendResult;
561 AsyncSuspendAlreadySuspended,
563 AsyncSuspendInitSuspend,
564 } MonoRequestAsyncSuspendResult;
566 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
567 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
568 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
569 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
570 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
571 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
572 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
573 void mono_threads_transition_async_suspend_compensation (THREAD_INFO_TYPE* info);
575 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
577 /* Advanced suspend API, used for suspending multiple threads as once. */
578 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
579 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
580 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
581 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
582 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
583 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
586 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
587 gboolean mono_threads_wait_pending_operations (void);
588 void mono_threads_begin_global_suspend (void);
589 void mono_threads_end_global_suspend (void);
591 #endif /* __MONO_THREADS_H__ */