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
123 #if defined (USE_COOP_GC)
124 #define USE_COOP_BACKEND
125 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 1
127 #elif defined (_POSIX_VERSION) || defined (__native_client__)
128 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 0
130 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
131 #define USE_MACH_BACKEND
133 #define USE_POSIX_BACKEND
137 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 0
138 #define USE_WINDOWS_BACKEND
143 STATE_STARTING = 0x00,
144 STATE_RUNNING = 0x01,
145 STATE_DETACHED = 0x02,
147 STATE_ASYNC_SUSPENDED = 0x03,
148 STATE_SELF_SUSPENDED = 0x04,
149 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
150 STATE_SELF_SUSPEND_REQUESTED = 0x06,
151 STATE_BLOCKING = 0x07,
152 STATE_BLOCKING_AND_SUSPENDED = 0x8,
156 THREAD_STATE_MASK = 0x00FF,
157 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
158 THREAD_SUSPEND_COUNT_SHIFT = 8,
159 THREAD_SUSPEND_COUNT_MAX = 0xFF,
161 SELF_SUSPEND_STATE_INDEX = 0,
162 ASYNC_SUSPEND_STATE_INDEX = 1,
166 * This enum tells which async thread service corresponds to which bit.
169 MONO_SERVICE_REQUEST_SAMPLE = 1,
173 MonoLinkedListSetNode node;
174 guint32 small_id; /*Used by hazard pointers */
175 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
178 /*Tells if this thread was created by the runtime or not.*/
179 gboolean runtime_thread;
181 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
182 gboolean tools_thread;
184 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
185 void *stack_start_limit, *stack_end;
187 /* suspend machinery, fields protected by suspend_semaphore */
188 MonoSemType suspend_semaphore;
191 MonoSemType resume_semaphore;
193 /* only needed by the posix backend */
194 #if defined(USE_POSIX_BACKEND)
195 MonoSemType finish_resume_semaphore;
196 gboolean syscall_break_signal;
197 gboolean suspend_can_continue;
202 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
203 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
205 /*async call machinery, thread MUST be suspended before accessing those fields*/
206 void (*async_target)(void*);
210 If true, this thread is running a critical region of code and cannot be suspended.
211 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
212 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
214 gboolean inside_critical_region;
217 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
218 * operations like locking without having to pass an 'async' parameter around.
220 gboolean is_async_context;
222 gboolean create_suspended;
224 /* Semaphore used to implement CREATE_SUSPENDED */
225 MonoSemType create_suspended_sem;
228 * Values of TLS variables for this thread.
229 * This can be used to obtain the values of TLS variable for threads
230 * other than the current one.
232 gpointer tls [TLS_KEY_NUM];
234 /* IO layer handle for this thread */
235 /* Set when the thread is started, or in _wapi_thread_duplicate () */
238 /* 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.
239 * Use the mono_threads_add_async_job and mono_threads_consume_async_jobs APIs to modify this flag.
240 * In the future the signaling should be part of the API, but for now, it's only for massaging the bits.
242 volatile gint32 service_requests;
248 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
250 This callback is called with @info still on the thread list.
251 This call is made while holding the suspend lock, so don't do callbacks.
252 SMR remains functional as its small_id has not been reclaimed.
254 void (*thread_unregister)(THREAD_INFO_TYPE *info);
256 This callback is called right before thread_unregister. This is called
257 without any locks held so it's the place for complicated cleanup.
259 The thread must remain operational between this call and thread_unregister.
260 It must be possible to successfully suspend it after thread_unregister completes.
262 void (*thread_detach)(THREAD_INFO_TYPE *info);
263 void (*thread_attach)(THREAD_INFO_TYPE *info);
264 gboolean (*mono_method_is_critical) (void *method);
265 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
266 void (*thread_exit)(void *retval);
268 int (*mono_gc_pthread_create) (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg);
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 } MonoThreadInfoRuntimeCallbacks;
278 //Not using 0 and 1 to ensure callbacks are not returning bad data
280 MonoResumeThread = 0x1234,
281 KeepSuspended = 0x4321,
282 } SuspendThreadResult;
284 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
286 static inline gboolean
287 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
289 return !((MonoThreadInfo*)info)->tools_thread;
293 Requires the world to be stoped
295 #define FOREACH_THREAD(thread) MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), thread, mono_threads_filter_tools_threads, THREAD_INFO_TYPE*)
296 #define END_FOREACH_THREAD MONO_LLS_END_FOREACH
301 #define FOREACH_THREAD_SAFE(thread) MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), thread, mono_threads_filter_tools_threads, THREAD_INFO_TYPE*)
302 #define END_FOREACH_THREAD_SAFE MONO_LLS_END_FOREACH_SAFE
304 #define mono_thread_info_get_tid(info) ((MonoNativeThreadId)((MonoThreadInfo*)info)->node.key)
305 #define mono_thread_info_set_tid(info, val) do { ((MonoThreadInfo*)(info))->node.key = (uintptr_t)(val); } while (0)
308 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
309 * a single block with info from both camps.
312 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
315 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
317 MonoThreadInfoCallbacks *
318 mono_threads_get_callbacks (void);
320 MonoThreadInfoRuntimeCallbacks *
321 mono_threads_get_runtime_callbacks (void);
324 mono_thread_info_register_small_id (void);
327 mono_thread_info_attach (void *baseptr);
330 mono_thread_info_detach (void);
333 mono_thread_info_is_exiting (void);
336 mono_thread_info_current (void);
339 mono_thread_info_current_unchecked (void);
342 mono_thread_info_get_small_id (void);
345 mono_thread_info_list_head (void);
348 mono_thread_info_lookup (MonoNativeThreadId id);
351 mono_thread_info_safe_suspend_sync (MonoNativeThreadId tid, gboolean interrupt_kernel);
354 mono_thread_info_resume (MonoNativeThreadId tid);
357 mono_thread_info_set_name (MonoNativeThreadId tid, const char *name);
360 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
362 //XXX new API, fix the world
364 mono_thread_info_begin_self_suspend (void);
367 mono_thread_info_end_self_suspend (void);
372 mono_thread_info_new_interrupt_enabled (void);
375 mono_thread_info_unified_management_enabled (void);
378 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
381 mono_thread_info_suspend_lock (void);
384 mono_thread_info_suspend_unlock (void);
387 mono_thread_info_disable_new_interrupt (gboolean disable);
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_prepare_interrupt (HANDLE thread_handle);
420 mono_thread_info_finish_interrupt (gpointer wait_handle);
423 mono_thread_info_interrupt (HANDLE thread_handle);
426 mono_thread_info_self_interrupt (void);
429 mono_thread_info_clear_interruption (void);
432 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
435 mono_threads_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
438 mono_threads_get_max_stack_size (void);
441 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
444 This is the async job submission/consumption API.
445 XXX: This is a PROVISIONAL API only meant to be used by the statistical profiler.
446 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.
449 mono_threads_add_async_job (THREAD_INFO_TYPE *info, MonoAsyncJob job);
452 mono_threads_consume_async_jobs (void);
455 mono_threads_attach_tools_thread (void);
458 #if !defined(HOST_WIN32)
460 /*Use this instead of pthread_kill */
462 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
464 #endif /* !defined(HOST_WIN32) */
466 /* Plartform specific functions DON'T use them */
467 void mono_threads_init_platform (void); //ok
468 gboolean mono_threads_core_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
469 gboolean mono_threads_core_resume (THREAD_INFO_TYPE *info);
470 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
471 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
472 void mono_threads_core_interrupt (THREAD_INFO_TYPE *info);
473 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
474 gboolean mono_threads_core_needs_abort_syscall (void);
475 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
476 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
477 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
478 gboolean mono_threads_core_yield (void);
479 void mono_threads_core_exit (int exit_code);
480 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
481 HANDLE mono_threads_core_open_handle (void);
482 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
483 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
485 /* Internal API between mono-threads and its backends. */
487 /* Backend functions - a backend must implement all of the following */
489 This is called very early in the runtime, it cannot access any runtime facilities.
492 void mono_threads_init_platform (void); //ok
495 This begins async suspend. This function must do the following:
497 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
498 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
499 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
501 If begin suspend fails the thread must be left uninterrupted and resumed.
503 gboolean mono_threads_core_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
506 This verifies the outcome of an async suspend operation.
508 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
509 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
511 gboolean mono_threads_core_check_suspend_result (THREAD_INFO_TYPE *info);
514 This begins async resume. This function must do the following:
516 - Install an async target if one was requested.
517 - Notify the target to resume.
518 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
520 gboolean mono_threads_core_begin_async_resume (THREAD_INFO_TYPE *info);
522 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
523 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
524 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
525 gboolean mono_threads_core_needs_abort_syscall (void);
526 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
527 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
528 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
529 gboolean mono_threads_core_yield (void);
530 void mono_threads_core_exit (int exit_code);
531 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
532 HANDLE mono_threads_core_open_handle (void);
533 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
534 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
535 gpointer mono_threads_core_prepare_interrupt (HANDLE thread_handle);
536 void mono_threads_core_finish_interrupt (gpointer wait_handle);
537 void mono_threads_core_self_interrupt (void);
538 void mono_threads_core_clear_interruption (void);
540 MonoNativeThreadId mono_native_thread_id_get (void);
542 gboolean mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
545 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
547 /*Mach specific internals */
548 void mono_threads_init_dead_letter (void);
549 void mono_threads_install_dead_letter (void);
551 /* mono-threads internal API used by the backends. */
553 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
555 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
557 This tells the resume initiator that we completed resume duties and will return to runnable state.
559 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
561 /* Thread state machine functions */
566 ResumeInitSelfResume,
567 ResumeInitAsyncResume,
568 ResumeInitBlockingResume,
574 SelfSuspendNotifyAndWait,
575 } MonoSelfSupendResult;
578 AsyncSuspendAlreadySuspended,
580 AsyncSuspendInitSuspend,
581 } MonoRequestAsyncSuspendResult;
584 DoBlockingContinue, //in blocking mode, continue
585 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
586 } MonoDoBlockingResult;
589 DoneBlockingAborted, //blocking was aborted and not properly restored, poll the state
590 DoneBlockingOk, //exited blocking fine
591 DoneBlockingWait, //thread should end suspended
592 } MonoDoneBlockingResult;
596 AbortBlockingIgnore, //Ignore
597 AbortBlockingIgnoreAndPoll, //Ignore and pool
598 AbortBlockingOk, //Abort worked
599 AbortBlockingOkAndPool, //Abort worked, but pool before
600 } MonoAbortBlockingResult;
603 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
604 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
605 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
606 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
607 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
608 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
609 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
610 void mono_threads_transition_async_suspend_compensation (THREAD_INFO_TYPE* info);
611 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
612 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
613 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
615 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
617 /* Advanced suspend API, used for suspending multiple threads as once. */
618 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
619 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
620 int mono_thread_info_suspend_count (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__ */