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>
18 #include <mono/utils/mono-threads-coop.h>
26 typedef DWORD MonoNativeThreadId;
27 typedef HANDLE MonoNativeThreadHandle; /* unused */
29 typedef DWORD mono_native_thread_return_t;
31 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (tid)
32 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) ((MonoNativeThreadId)(tid))
39 #include <mono/utils/mach-support.h>
41 typedef thread_port_t MonoNativeThreadHandle;
47 typedef pid_t MonoNativeThreadHandle;
49 #endif /* defined(__MACH__) */
51 typedef pthread_t MonoNativeThreadId;
53 typedef void* mono_native_thread_return_t;
55 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (gsize)(tid)
56 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) (MonoNativeThreadId)(gsize)(tid)
58 #endif /* #ifdef HOST_WIN32 */
61 THREAD_INFO_TYPE is a way to make the mono-threads module parametric - or sort of.
62 The GC using mono-threads might extend the MonoThreadInfo struct to add its own
63 data, this avoid a pointer indirection on what is on a lot of hot paths.
65 But extending MonoThreadInfo has de disavantage that all functions here return type
66 would require a cast, something like the following:
74 ((MyThreadInfo*)mono_thread_info_current ())->stuff = 1;
76 While porting sgen to use mono-threads, the number of casts required was too much and
77 code ended up looking horrible. So we use this cute little hack. The idea is that
78 whomever is including this header can set the expected type to be used by functions here
79 and reduce the number of casts drastically.
82 #ifndef THREAD_INFO_TYPE
83 #define THREAD_INFO_TYPE MonoThreadInfo
86 /* Mono Threads internal configuration knows*/
88 /* Logging - enable them below if you need specific logging for the category you need */
89 #define MOSTLY_ASYNC_SAFE_PRINTF(...) do { \
90 char __buff[1024]; __buff [0] = '\0'; \
91 g_snprintf (__buff, sizeof (__buff), __VA_ARGS__); \
92 write (1, __buff, strlen (__buff)); \
97 #define THREADS_DEBUG(...)
99 #define THREADS_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
103 #define THREADS_STW_DEBUG(...)
105 #define THREADS_STW_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
109 #define THREADS_SUSPEND_DEBUG(...)
111 #define THREADS_SUSPEND_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
115 #define THREADS_STATE_MACHINE_DEBUG(...)
117 #define THREADS_STATE_MACHINE_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
120 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
121 // #define USE_SIGNALS_ON_MACH
124 #if defined (USE_COOP_GC)
125 #define USE_COOP_BACKEND
126 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 1
128 #elif defined (_POSIX_VERSION) || defined (__native_client__)
129 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 0
131 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
132 #define USE_MACH_BACKEND
134 #define USE_POSIX_BACKEND
138 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 0
139 #define USE_WINDOWS_BACKEND
144 STATE_STARTING = 0x00,
145 STATE_RUNNING = 0x01,
146 STATE_DETACHED = 0x02,
148 STATE_ASYNC_SUSPENDED = 0x03,
149 STATE_SELF_SUSPENDED = 0x04,
150 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
151 STATE_SELF_SUSPEND_REQUESTED = 0x06,
152 STATE_BLOCKING = 0x07,
153 STATE_BLOCKING_AND_SUSPENDED = 0x8,
157 THREAD_STATE_MASK = 0x00FF,
158 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
159 THREAD_SUSPEND_COUNT_SHIFT = 8,
160 THREAD_SUSPEND_COUNT_MAX = 0xFF,
162 SELF_SUSPEND_STATE_INDEX = 0,
163 ASYNC_SUSPEND_STATE_INDEX = 1,
167 * This enum tells which async thread service corresponds to which bit.
170 MONO_SERVICE_REQUEST_SAMPLE = 1,
174 MonoLinkedListSetNode node;
175 guint32 small_id; /*Used by hazard pointers */
176 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
179 /*Tells if this thread was created by the runtime or not.*/
180 gboolean runtime_thread;
182 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
183 gboolean tools_thread;
185 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
186 void *stack_start_limit, *stack_end;
188 /* suspend machinery, fields protected by suspend_semaphore */
189 MonoSemType suspend_semaphore;
192 MonoSemType resume_semaphore;
194 /* only needed by the posix backend */
195 #if defined(USE_POSIX_BACKEND)
196 MonoSemType finish_resume_semaphore;
197 gboolean syscall_break_signal;
198 gboolean suspend_can_continue;
203 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
204 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
206 /*async call machinery, thread MUST be suspended before accessing those fields*/
207 void (*async_target)(void*);
211 If true, this thread is running a critical region of code and cannot be suspended.
212 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
213 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
215 gboolean inside_critical_region;
218 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
219 * operations like locking without having to pass an 'async' parameter around.
221 gboolean is_async_context;
223 gboolean create_suspended;
225 /* Semaphore used to implement CREATE_SUSPENDED */
226 MonoSemType create_suspended_sem;
229 * Values of TLS variables for this thread.
230 * This can be used to obtain the values of TLS variable for threads
231 * other than the current one.
233 gpointer tls [TLS_KEY_NUM];
235 /* IO layer handle for this thread */
236 /* Set when the thread is started, or in _wapi_thread_duplicate () */
239 /* 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.
240 * Use the mono_threads_add_async_job and mono_threads_consume_async_jobs APIs to modify this flag.
241 * In the future the signaling should be part of the API, but for now, it's only for massaging the bits.
243 volatile gint32 service_requests;
249 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
251 This callback is called with @info still on the thread list.
252 This call is made while holding the suspend lock, so don't do callbacks.
253 SMR remains functional as its small_id has not been reclaimed.
255 void (*thread_unregister)(THREAD_INFO_TYPE *info);
257 This callback is called right before thread_unregister. This is called
258 without any locks held so it's the place for complicated cleanup.
260 The thread must remain operational between this call and thread_unregister.
261 It must be possible to successfully suspend it after thread_unregister completes.
263 void (*thread_detach)(THREAD_INFO_TYPE *info);
264 void (*thread_attach)(THREAD_INFO_TYPE *info);
265 gboolean (*mono_method_is_critical) (void *method);
266 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
267 } MonoThreadInfoCallbacks;
270 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
271 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
272 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
273 } MonoThreadInfoRuntimeCallbacks;
275 //Not using 0 and 1 to ensure callbacks are not returning bad data
277 MonoResumeThread = 0x1234,
278 KeepSuspended = 0x4321,
279 } SuspendThreadResult;
281 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
283 static inline gboolean
284 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
286 return !((MonoThreadInfo*)info)->tools_thread;
290 Requires the world to be stoped
292 #define FOREACH_THREAD(thread) MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), thread, mono_threads_filter_tools_threads, THREAD_INFO_TYPE*)
293 #define END_FOREACH_THREAD MONO_LLS_END_FOREACH
298 #define FOREACH_THREAD_SAFE(thread) MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), thread, mono_threads_filter_tools_threads, THREAD_INFO_TYPE*)
299 #define END_FOREACH_THREAD_SAFE MONO_LLS_END_FOREACH_SAFE
301 #define mono_thread_info_get_tid(info) ((MonoNativeThreadId)((MonoThreadInfo*)info)->node.key)
302 #define mono_thread_info_set_tid(info, val) do { ((MonoThreadInfo*)(info))->node.key = (uintptr_t)(val); } while (0)
305 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
306 * a single block with info from both camps.
309 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
312 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
314 MonoThreadInfoRuntimeCallbacks *
315 mono_threads_get_runtime_callbacks (void);
318 mono_thread_info_register_small_id (void);
321 mono_thread_info_attach (void *baseptr);
324 mono_thread_info_detach (void);
327 mono_thread_info_is_exiting (void);
330 mono_thread_info_current (void);
333 mono_thread_info_current_unchecked (void);
336 mono_thread_info_get_small_id (void);
339 mono_thread_info_list_head (void);
342 mono_thread_info_lookup (MonoNativeThreadId id);
345 mono_thread_info_safe_suspend_sync (MonoNativeThreadId tid, gboolean interrupt_kernel);
348 mono_thread_info_resume (MonoNativeThreadId tid);
351 mono_thread_info_set_name (MonoNativeThreadId tid, const char *name);
354 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
356 //XXX new API, fix the world
358 mono_thread_info_begin_self_suspend (void);
361 mono_thread_info_end_self_suspend (void);
366 mono_thread_info_unified_management_enabled (void);
369 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
372 mono_thread_info_suspend_lock (void);
375 mono_thread_info_suspend_unlock (void);
378 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
381 mono_thread_info_set_is_async_context (gboolean async_context);
384 mono_thread_info_is_async_context (void);
387 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
390 mono_thread_info_yield (void);
393 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
396 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
399 mono_thread_info_exit (void);
402 mono_thread_info_open_handle (void);
405 mono_thread_info_prepare_interrupt (HANDLE thread_handle);
408 mono_thread_info_finish_interrupt (gpointer wait_handle);
411 mono_thread_info_interrupt (HANDLE thread_handle);
414 mono_thread_info_self_interrupt (void);
417 mono_thread_info_clear_interruption (void);
420 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
423 mono_threads_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
426 mono_threads_get_max_stack_size (void);
429 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
432 This is the async job submission/consumption API.
433 XXX: This is a PROVISIONAL API only meant to be used by the statistical profiler.
434 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.
437 mono_threads_add_async_job (THREAD_INFO_TYPE *info, MonoAsyncJob job);
440 mono_threads_consume_async_jobs (void);
443 mono_threads_attach_tools_thread (void);
446 #if !defined(HOST_WIN32)
448 /*Use this instead of pthread_kill */
450 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
452 #endif /* !defined(HOST_WIN32) */
454 /* Plartform specific functions DON'T use them */
455 void mono_threads_init_platform (void); //ok
456 gboolean mono_threads_core_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
457 gboolean mono_threads_core_resume (THREAD_INFO_TYPE *info);
458 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
459 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
460 void mono_threads_core_interrupt (THREAD_INFO_TYPE *info);
461 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
462 gboolean mono_threads_core_needs_abort_syscall (void);
463 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
464 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
465 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
466 gboolean mono_threads_core_yield (void);
467 void mono_threads_core_exit (int exit_code);
468 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
469 HANDLE mono_threads_core_open_handle (void);
470 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
471 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
473 void mono_threads_core_begin_global_suspend (void);
474 void mono_threads_core_end_global_suspend (void);
476 /* Internal API between mono-threads and its backends. */
478 /* Backend functions - a backend must implement all of the following */
480 This is called very early in the runtime, it cannot access any runtime facilities.
483 void mono_threads_init_platform (void); //ok
486 This begins async suspend. This function must do the following:
488 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
489 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
490 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
492 If begin suspend fails the thread must be left uninterrupted and resumed.
494 gboolean mono_threads_core_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
497 This verifies the outcome of an async suspend operation.
499 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
500 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
502 gboolean mono_threads_core_check_suspend_result (THREAD_INFO_TYPE *info);
505 This begins async resume. This function must do the following:
507 - Install an async target if one was requested.
508 - Notify the target to resume.
509 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
511 gboolean mono_threads_core_begin_async_resume (THREAD_INFO_TYPE *info);
513 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
514 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
515 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
516 gboolean mono_threads_core_needs_abort_syscall (void);
517 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
518 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
519 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
520 gboolean mono_threads_core_yield (void);
521 void mono_threads_core_exit (int exit_code);
522 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
523 HANDLE mono_threads_core_open_handle (void);
524 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
525 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
526 gpointer mono_threads_core_prepare_interrupt (HANDLE thread_handle);
527 void mono_threads_core_finish_interrupt (gpointer wait_handle);
528 void mono_threads_core_self_interrupt (void);
529 void mono_threads_core_clear_interruption (void);
531 MonoNativeThreadId mono_native_thread_id_get (void);
533 gboolean mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
536 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
538 /*Mach specific internals */
539 void mono_threads_init_dead_letter (void);
540 void mono_threads_install_dead_letter (void);
542 /* mono-threads internal API used by the backends. */
544 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
546 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
548 This tells the resume initiator that we completed resume duties and will return to runnable state.
550 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
553 This tells the resume initiator that we completed abort duties and will return to previous state.
555 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
557 /* Thread state machine functions */
562 ResumeInitSelfResume,
563 ResumeInitAsyncResume,
564 ResumeInitBlockingResume,
570 SelfSuspendNotifyAndWait,
571 } MonoSelfSupendResult;
574 AsyncSuspendAlreadySuspended,
576 AsyncSuspendInitSuspend,
577 } MonoRequestAsyncSuspendResult;
580 DoBlockingContinue, //in blocking mode, continue
581 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
582 } MonoDoBlockingResult;
585 DoneBlockingAborted, //blocking was aborted and not properly restored, poll the state
586 DoneBlockingOk, //exited blocking fine
587 DoneBlockingWait, //thread should end suspended
588 } MonoDoneBlockingResult;
592 AbortBlockingIgnore, //Ignore
593 AbortBlockingIgnoreAndPoll, //Ignore and pool
594 AbortBlockingOk, //Abort worked
595 AbortBlockingOkAndPool, //Abort worked, but pool before
596 } MonoAbortBlockingResult;
599 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
600 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
601 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
602 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
603 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
604 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
605 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
606 void mono_threads_transition_async_suspend_compensation (THREAD_INFO_TYPE* info);
607 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
608 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
609 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
611 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
614 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
615 /* Advanced suspend API, used for suspending multiple threads as once. */
616 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
617 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
618 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
619 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
621 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
622 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
623 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
626 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
627 gboolean mono_threads_wait_pending_operations (void);
628 void mono_threads_begin_global_suspend (void);
629 void mono_threads_end_global_suspend (void);
631 #endif /* __MONO_THREADS_H__ */