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>
19 #include <mono/utils/mono-threads-api.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))
40 #include <mono/utils/mach-support.h>
42 typedef thread_port_t MonoNativeThreadHandle;
48 typedef pid_t MonoNativeThreadHandle;
50 #endif /* defined(__MACH__) */
52 typedef pthread_t MonoNativeThreadId;
54 typedef void* mono_native_thread_return_t;
56 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (gsize)(tid)
57 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) (MonoNativeThreadId)(gsize)(tid)
59 #endif /* #ifdef HOST_WIN32 */
62 THREAD_INFO_TYPE is a way to make the mono-threads module parametric - or sort of.
63 The GC using mono-threads might extend the MonoThreadInfo struct to add its own
64 data, this avoid a pointer indirection on what is on a lot of hot paths.
66 But extending MonoThreadInfo has de disavantage that all functions here return type
67 would require a cast, something like the following:
75 ((MyThreadInfo*)mono_thread_info_current ())->stuff = 1;
77 While porting sgen to use mono-threads, the number of casts required was too much and
78 code ended up looking horrible. So we use this cute little hack. The idea is that
79 whomever is including this header can set the expected type to be used by functions here
80 and reduce the number of casts drastically.
83 #ifndef THREAD_INFO_TYPE
84 #define THREAD_INFO_TYPE MonoThreadInfo
87 /* Mono Threads internal configuration knows*/
89 /* Logging - enable them below if you need specific logging for the category you need */
90 #define MOSTLY_ASYNC_SAFE_PRINTF(...) do { \
91 char __buff[1024]; __buff [0] = '\0'; \
92 g_snprintf (__buff, sizeof (__buff), __VA_ARGS__); \
93 write (1, __buff, strlen (__buff)); \
98 #define THREADS_DEBUG(...)
100 #define THREADS_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
104 #define THREADS_STW_DEBUG(...)
106 #define THREADS_STW_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
110 #define THREADS_SUSPEND_DEBUG(...)
112 #define THREADS_SUSPEND_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
116 #define THREADS_STATE_MACHINE_DEBUG(...)
118 #define THREADS_STATE_MACHINE_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
122 #define THREADS_INTERRUPT_DEBUG(...)
124 #define THREADS_INTERRUPT_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
127 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
128 // #define USE_SIGNALS_ON_MACH
131 #if defined (USE_COOP_GC)
132 #define USE_COOP_BACKEND
133 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 1
135 #elif defined (_POSIX_VERSION) || defined (__native_client__)
136 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 0
138 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
139 #define USE_MACH_BACKEND
141 #define USE_POSIX_BACKEND
145 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 0
146 #define USE_WINDOWS_BACKEND
151 STATE_STARTING = 0x00,
152 STATE_RUNNING = 0x01,
153 STATE_DETACHED = 0x02,
155 STATE_ASYNC_SUSPENDED = 0x03,
156 STATE_SELF_SUSPENDED = 0x04,
157 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
158 STATE_SELF_SUSPEND_REQUESTED = 0x06,
159 STATE_BLOCKING = 0x07,
160 STATE_BLOCKING_AND_SUSPENDED = 0x8,
164 THREAD_STATE_MASK = 0x00FF,
165 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
166 THREAD_SUSPEND_COUNT_SHIFT = 8,
167 THREAD_SUSPEND_COUNT_MAX = 0xFF,
169 SELF_SUSPEND_STATE_INDEX = 0,
170 ASYNC_SUSPEND_STATE_INDEX = 1,
174 * This enum tells which async thread service corresponds to which bit.
177 MONO_SERVICE_REQUEST_SAMPLE = 1,
180 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
183 MonoLinkedListSetNode node;
184 guint32 small_id; /*Used by hazard pointers */
185 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
188 /*Tells if this thread was created by the runtime or not.*/
189 gboolean runtime_thread;
191 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
192 gboolean tools_thread;
194 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
195 void *stack_start_limit, *stack_end;
197 /* suspend machinery, fields protected by suspend_semaphore */
198 MonoSemType suspend_semaphore;
201 MonoSemType resume_semaphore;
203 /* only needed by the posix backend */
204 #if defined(USE_POSIX_BACKEND)
205 MonoSemType finish_resume_semaphore;
206 gboolean syscall_break_signal;
207 gboolean suspend_can_continue;
212 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
213 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
215 /*async call machinery, thread MUST be suspended before accessing those fields*/
216 void (*async_target)(void*);
220 If true, this thread is running a critical region of code and cannot be suspended.
221 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
222 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
224 gboolean inside_critical_region;
227 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
228 * operations like locking without having to pass an 'async' parameter around.
230 gboolean is_async_context;
232 gboolean create_suspended;
234 /* Semaphore used to implement CREATE_SUSPENDED */
235 MonoSemType create_suspended_sem;
238 * Values of TLS variables for this thread.
239 * This can be used to obtain the values of TLS variable for threads
240 * other than the current one.
242 gpointer tls [TLS_KEY_NUM];
244 /* IO layer handle for this thread */
245 /* Set when the thread is started, or in _wapi_thread_duplicate () */
248 /* 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.
249 * Use the mono_threads_add_async_job and mono_threads_consume_async_jobs APIs to modify this flag.
250 * In the future the signaling should be part of the API, but for now, it's only for massaging the bits.
252 volatile gint32 service_requests;
256 MonoThreadInfoInterruptToken *interrupt_token;
260 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
262 This callback is called with @info still on the thread list.
263 This call is made while holding the suspend lock, so don't do callbacks.
264 SMR remains functional as its small_id has not been reclaimed.
266 void (*thread_unregister)(THREAD_INFO_TYPE *info);
268 This callback is called right before thread_unregister. This is called
269 without any locks held so it's the place for complicated cleanup.
271 The thread must remain operational between this call and thread_unregister.
272 It must be possible to successfully suspend it after thread_unregister completes.
274 void (*thread_detach)(THREAD_INFO_TYPE *info);
275 void (*thread_attach)(THREAD_INFO_TYPE *info);
276 gboolean (*mono_method_is_critical) (void *method);
277 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
278 } MonoThreadInfoCallbacks;
281 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
282 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
283 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
284 void (*thread_state_init) (MonoThreadUnwindState *tctx);
285 } MonoThreadInfoRuntimeCallbacks;
287 //Not using 0 and 1 to ensure callbacks are not returning bad data
289 MonoResumeThread = 0x1234,
290 KeepSuspended = 0x4321,
291 } SuspendThreadResult;
293 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
295 static inline gboolean
296 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
298 return !((MonoThreadInfo*)info)->tools_thread;
302 Requires the world to be stoped
304 #define FOREACH_THREAD(thread) MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), thread, mono_threads_filter_tools_threads, THREAD_INFO_TYPE*)
305 #define END_FOREACH_THREAD MONO_LLS_END_FOREACH
310 #define FOREACH_THREAD_SAFE(thread) MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), thread, mono_threads_filter_tools_threads, THREAD_INFO_TYPE*)
311 #define END_FOREACH_THREAD_SAFE MONO_LLS_END_FOREACH_SAFE
313 #define mono_thread_info_get_tid(info) ((MonoNativeThreadId)((MonoThreadInfo*)info)->node.key)
314 #define mono_thread_info_set_tid(info, val) do { ((MonoThreadInfo*)(info))->node.key = (uintptr_t)(val); } while (0)
317 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
318 * a single block with info from both camps.
321 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
324 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
326 MonoThreadInfoRuntimeCallbacks *
327 mono_threads_get_runtime_callbacks (void);
330 mono_thread_info_register_small_id (void);
333 mono_thread_info_attach (void *baseptr);
336 mono_thread_info_detach (void);
339 mono_thread_info_is_exiting (void);
342 mono_thread_info_current (void);
345 mono_thread_info_current_unchecked (void);
348 mono_thread_info_get_small_id (void);
351 mono_thread_info_list_head (void);
354 mono_thread_info_lookup (MonoNativeThreadId id);
357 mono_thread_info_safe_suspend_sync (MonoNativeThreadId tid, gboolean interrupt_kernel);
360 mono_thread_info_resume (MonoNativeThreadId tid);
363 mono_thread_info_set_name (MonoNativeThreadId tid, const char *name);
366 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
368 //XXX new API, fix the world
370 mono_thread_info_begin_self_suspend (void);
373 mono_thread_info_end_self_suspend (void);
378 mono_thread_info_unified_management_enabled (void);
381 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
384 mono_thread_info_suspend_lock (void);
387 mono_thread_info_suspend_unlock (void);
390 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
393 mono_thread_info_set_is_async_context (gboolean async_context);
396 mono_thread_info_is_async_context (void);
399 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
402 mono_thread_info_yield (void);
405 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
408 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
411 mono_thread_info_exit (void);
414 mono_thread_info_open_handle (void);
417 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
420 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
422 MonoThreadInfoInterruptToken*
423 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
426 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
429 mono_thread_info_self_interrupt (void);
432 mono_thread_info_clear_self_interrupt (void);
435 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
438 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
441 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
444 mono_threads_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
447 mono_threads_get_max_stack_size (void);
450 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
453 This is the async job submission/consumption API.
454 XXX: This is a PROVISIONAL API only meant to be used by the statistical profiler.
455 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.
458 mono_threads_add_async_job (THREAD_INFO_TYPE *info, MonoAsyncJob job);
461 mono_threads_consume_async_jobs (void);
464 mono_threads_attach_tools_thread (void);
467 #if !defined(HOST_WIN32)
469 /*Use this instead of pthread_kill */
471 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
473 #endif /* !defined(HOST_WIN32) */
475 /* Plartform specific functions DON'T use them */
476 void mono_threads_init_platform (void); //ok
477 gboolean mono_threads_core_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
478 gboolean mono_threads_core_resume (THREAD_INFO_TYPE *info);
479 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
480 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
481 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
482 gboolean mono_threads_core_needs_abort_syscall (void);
483 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
484 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
485 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
486 gboolean mono_threads_core_yield (void);
487 void mono_threads_core_exit (int exit_code);
488 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
489 HANDLE mono_threads_core_open_handle (void);
490 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
491 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
493 void mono_threads_core_begin_global_suspend (void);
494 void mono_threads_core_end_global_suspend (void);
496 /* Internal API between mono-threads and its backends. */
498 /* Backend functions - a backend must implement all of the following */
500 This is called very early in the runtime, it cannot access any runtime facilities.
503 void mono_threads_init_platform (void); //ok
506 This begins async suspend. This function must do the following:
508 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
509 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
510 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
512 If begin suspend fails the thread must be left uninterrupted and resumed.
514 gboolean mono_threads_core_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
517 This verifies the outcome of an async suspend operation.
519 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
520 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
522 gboolean mono_threads_core_check_suspend_result (THREAD_INFO_TYPE *info);
525 This begins async resume. This function must do the following:
527 - Install an async target if one was requested.
528 - Notify the target to resume.
529 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
531 gboolean mono_threads_core_begin_async_resume (THREAD_INFO_TYPE *info);
533 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
534 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
535 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
536 gboolean mono_threads_core_needs_abort_syscall (void);
537 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
538 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
539 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
540 gboolean mono_threads_core_yield (void);
541 void mono_threads_core_exit (int exit_code);
542 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
543 HANDLE mono_threads_core_open_handle (void);
544 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
545 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
547 MonoNativeThreadId mono_native_thread_id_get (void);
549 gboolean mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
552 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
554 /*Mach specific internals */
555 void mono_threads_init_dead_letter (void);
556 void mono_threads_install_dead_letter (void);
558 /* mono-threads internal API used by the backends. */
560 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
562 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
564 This tells the resume initiator that we completed resume duties and will return to runnable state.
566 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
569 This tells the resume initiator that we completed abort duties and will return to previous state.
571 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
573 /* Thread state machine functions */
578 ResumeInitSelfResume,
579 ResumeInitAsyncResume,
580 ResumeInitBlockingResume,
586 SelfSuspendNotifyAndWait,
587 } MonoSelfSupendResult;
590 AsyncSuspendAlreadySuspended,
592 AsyncSuspendInitSuspend,
593 } MonoRequestAsyncSuspendResult;
596 DoBlockingContinue, //in blocking mode, continue
597 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
598 } MonoDoBlockingResult;
601 DoneBlockingAborted, //blocking was aborted and not properly restored, poll the state
602 DoneBlockingOk, //exited blocking fine
603 DoneBlockingWait, //thread should end suspended
604 } MonoDoneBlockingResult;
608 AbortBlockingIgnore, //Ignore
609 AbortBlockingIgnoreAndPoll, //Ignore and pool
610 AbortBlockingOk, //Abort worked
611 AbortBlockingOkAndPool, //Abort worked, but pool before
612 } MonoAbortBlockingResult;
615 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
616 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
617 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
618 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
619 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
620 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
621 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
622 void mono_threads_transition_async_suspend_compensation (THREAD_INFO_TYPE* info);
623 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
624 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
625 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
627 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
630 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
631 /* Advanced suspend API, used for suspending multiple threads as once. */
632 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
633 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
634 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
635 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
636 const char* mono_thread_state_name (int state);
638 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
639 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
640 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
643 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
644 gboolean mono_threads_wait_pending_operations (void);
645 void mono_threads_begin_global_suspend (void);
646 void mono_threads_end_global_suspend (void);
648 #endif /* __MONO_THREADS_H__ */