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>
19 #include <mono/io-layer/io-layer.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
130 #if defined (_POSIX_VERSION) || defined (__native_client__)
131 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
132 #define USE_MACH_BACKEND
134 #define USE_POSIX_BACKEND
137 #define USE_WINDOWS_BACKEND
139 #error "no backend support for current platform"
140 #endif /* defined (_POSIX_VERSION) || defined (__native_client__) */
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,
165 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
168 MonoLinkedListSetNode node;
169 guint32 small_id; /*Used by hazard pointers */
170 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
173 /*Tells if this thread was created by the runtime or not.*/
174 gboolean runtime_thread;
176 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
177 gboolean tools_thread;
179 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
180 void *stack_start_limit, *stack_end;
182 /* suspend machinery, fields protected by suspend_semaphore */
183 MonoSemType suspend_semaphore;
186 MonoSemType resume_semaphore;
188 /* only needed by the posix backend */
189 #if defined(USE_POSIX_BACKEND)
190 MonoSemType finish_resume_semaphore;
191 gboolean syscall_break_signal;
195 gboolean suspend_can_continue;
197 /* This memory pool is used by coop GC to save stack data roots between GC unsafe regions */
198 GByteArray *stackdata;
200 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
201 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
203 /*async call machinery, thread MUST be suspended before accessing those fields*/
204 void (*async_target)(void*);
208 If true, this thread is running a critical region of code and cannot be suspended.
209 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
210 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
212 gboolean inside_critical_region;
215 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
216 * operations like locking without having to pass an 'async' parameter around.
218 gboolean is_async_context;
220 gboolean create_suspended;
222 /* Semaphore used to implement CREATE_SUSPENDED */
223 MonoCoopSem create_suspended_sem;
226 * Values of TLS variables for this thread.
227 * This can be used to obtain the values of TLS variable for threads
228 * other than the current one.
230 gpointer tls [TLS_KEY_NUM];
232 /* IO layer handle for this thread */
233 /* Set when the thread is started, or in _wapi_thread_duplicate () */
238 MonoThreadInfoInterruptToken *interrupt_token;
240 /* HandleStack for coop handles */
241 gpointer handle_stack;
243 /* Stack mark for targets that explicitly require one */
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 } MonoThreadInfoCallbacks;
269 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
270 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
271 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
272 void (*thread_state_init) (MonoThreadUnwindState *tctx);
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);
284 * Parameters to pass for thread creation
288 guint32 creation_flags;
293 MONO_THREAD_PRIORITY_LOWEST = 0,
294 MONO_THREAD_PRIORITY_BELOW_NORMAL = 1,
295 MONO_THREAD_PRIORITY_NORMAL = 2,
296 MONO_THREAD_PRIORITY_ABOVE_NORMAL = 3,
297 MONO_THREAD_PRIORITY_HIGHEST = 4,
298 } MonoThreadPriority;
300 static inline gboolean
301 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
303 return !((MonoThreadInfo*)info)->tools_thread;
307 Requires the world to be stoped
309 #define FOREACH_THREAD(thread) \
310 MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
312 #define FOREACH_THREAD_END \
318 #define FOREACH_THREAD_SAFE(thread) \
319 MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
321 #define FOREACH_THREAD_SAFE_END \
322 MONO_LLS_FOREACH_SAFE_END
324 static inline MonoNativeThreadId
325 mono_thread_info_get_tid (THREAD_INFO_TYPE *info)
327 return MONO_UINT_TO_NATIVE_THREAD_ID (((MonoThreadInfo*) info)->node.key);
331 mono_thread_info_set_tid (THREAD_INFO_TYPE *info, MonoNativeThreadId tid)
333 ((MonoThreadInfo*) info)->node.key = (uintptr_t) MONO_NATIVE_THREAD_ID_TO_UINT (tid);
337 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
338 * a single block with info from both camps.
341 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
344 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
346 MonoThreadInfoRuntimeCallbacks *
347 mono_threads_get_runtime_callbacks (void);
350 mono_thread_info_register_small_id (void);
353 mono_thread_info_attach (void *baseptr);
356 mono_thread_info_detach (void);
359 mono_thread_info_is_exiting (void);
362 mono_thread_info_current (void);
365 mono_thread_info_current_unchecked (void);
368 mono_thread_info_get_small_id (void);
371 mono_thread_info_list_head (void);
374 mono_thread_info_lookup (MonoNativeThreadId id);
377 mono_thread_info_resume (MonoNativeThreadId tid);
380 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
382 //XXX new API, fix the world
384 mono_thread_info_begin_self_suspend (void);
387 mono_thread_info_end_self_suspend (void);
392 mono_thread_info_unified_management_enabled (void);
395 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
398 mono_thread_info_suspend_lock (void);
401 mono_thread_info_suspend_unlock (void);
404 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
407 mono_thread_info_set_is_async_context (gboolean async_context);
410 mono_thread_info_is_async_context (void);
413 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
416 mono_thread_info_yield (void);
419 mono_thread_info_sleep (guint32 ms, gboolean *alerted);
422 mono_thread_info_usleep (guint64 us);
425 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
428 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
431 mono_thread_info_exit (void);
434 mono_thread_info_open_handle (void);
437 mono_thread_info_set_exited (THREAD_INFO_TYPE *info);
440 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
443 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
445 MonoThreadInfoInterruptToken*
446 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
449 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
452 mono_thread_info_self_interrupt (void);
455 mono_thread_info_clear_self_interrupt (void);
458 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
461 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
464 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
467 mono_threads_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, MonoThreadParm *tp, MonoNativeThreadId *out_tid);
470 mono_threads_get_max_stack_size (void);
473 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
476 mono_threads_attach_tools_thread (void);
479 #if !defined(HOST_WIN32)
481 /*Use this instead of pthread_kill */
483 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
485 #endif /* !defined(HOST_WIN32) */
487 /* Internal API between mono-threads and its backends. */
489 /* Backend functions - a backend must implement all of the following */
491 This is called very early in the runtime, it cannot access any runtime facilities.
494 void mono_threads_suspend_init (void); //ok
496 void mono_threads_platform_init (void);
498 void mono_threads_coop_init (void);
500 void mono_threads_abort_syscall_init (void);
503 This begins async suspend. This function must do the following:
505 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
506 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
507 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
509 If begin suspend fails the thread must be left uninterrupted and resumed.
511 gboolean mono_threads_suspend_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
514 This verifies the outcome of an async suspend operation.
516 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
517 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
519 gboolean mono_threads_suspend_check_suspend_result (THREAD_INFO_TYPE *info);
522 This begins async resume. This function must do the following:
524 - Install an async target if one was requested.
525 - Notify the target to resume.
526 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
528 gboolean mono_threads_suspend_begin_async_resume (THREAD_INFO_TYPE *info);
530 void mono_threads_suspend_register (THREAD_INFO_TYPE *info); //ok
531 void mono_threads_suspend_free (THREAD_INFO_TYPE *info);
532 void mono_threads_suspend_abort_syscall (THREAD_INFO_TYPE *info);
533 gboolean mono_threads_suspend_needs_abort_syscall (void);
535 HANDLE mono_threads_platform_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, MonoThreadParm *, MonoNativeThreadId *out_tid);
536 void mono_threads_platform_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
537 void mono_threads_platform_get_stack_bounds (guint8 **staddr, size_t *stsize);
538 gboolean mono_threads_platform_yield (void);
539 void mono_threads_platform_exit (int exit_code);
540 void mono_threads_platform_unregister (THREAD_INFO_TYPE *info);
541 HANDLE mono_threads_platform_open_handle (void);
542 HANDLE mono_threads_platform_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
543 void mono_threads_platform_set_exited (THREAD_INFO_TYPE *info);
544 void mono_threads_platform_describe (THREAD_INFO_TYPE *info, GString *text);
545 void mono_threads_platform_own_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
546 void mono_threads_platform_disown_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
547 MonoThreadPriority mono_threads_platform_get_priority (THREAD_INFO_TYPE *info);
548 gboolean mono_threads_platform_set_priority (THREAD_INFO_TYPE *info, MonoThreadPriority priority);
550 void mono_threads_coop_begin_global_suspend (void);
551 void mono_threads_coop_end_global_suspend (void);
553 MONO_API MonoNativeThreadId
554 mono_native_thread_id_get (void);
557 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
560 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
563 mono_native_thread_set_name (MonoNativeThreadId tid, const char *name);
565 /*Mach specific internals */
566 void mono_threads_init_dead_letter (void);
567 void mono_threads_install_dead_letter (void);
569 /* mono-threads internal API used by the backends. */
571 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
573 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
575 This tells the resume initiator that we completed resume duties and will return to runnable state.
577 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
580 This tells the resume initiator that we completed abort duties and will return to previous state.
582 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
584 /* Thread state machine functions */
589 ResumeInitSelfResume,
590 ResumeInitAsyncResume,
591 ResumeInitBlockingResume,
597 SelfSuspendNotifyAndWait,
598 } MonoSelfSupendResult;
601 AsyncSuspendAlreadySuspended,
603 AsyncSuspendInitSuspend,
604 AsyncSuspendBlocking,
605 } MonoRequestAsyncSuspendResult;
608 DoBlockingContinue, //in blocking mode, continue
609 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
610 } MonoDoBlockingResult;
613 DoneBlockingOk, //exited blocking fine
614 DoneBlockingWait, //thread should end suspended
615 } MonoDoneBlockingResult;
619 AbortBlockingIgnore, //Ignore
620 AbortBlockingIgnoreAndPoll, //Ignore and poll
621 AbortBlockingOk, //Abort worked
622 AbortBlockingWait, //Abort worked, but should wait for resume
623 } MonoAbortBlockingResult;
626 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
627 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
628 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
629 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
630 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
631 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
632 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
633 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
634 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
635 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
637 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
640 mono_threads_enter_gc_unsafe_region_cookie (void);
643 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
644 /* Advanced suspend API, used for suspending multiple threads as once. */
645 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
646 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
647 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
648 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
649 const char* mono_thread_state_name (int state);
651 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
652 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
653 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
655 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
656 gboolean mono_threads_wait_pending_operations (void);
657 void mono_threads_begin_global_suspend (void);
658 void mono_threads_end_global_suspend (void);
661 mono_thread_info_is_current (THREAD_INFO_TYPE *info);
664 mono_thread_info_get_handle (THREAD_INFO_TYPE *info);
667 mono_thread_info_describe (THREAD_INFO_TYPE *info, GString *text);
670 mono_thread_info_own_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
673 mono_thread_info_disown_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
676 mono_thread_info_get_priority (THREAD_INFO_TYPE *info);
679 mono_thread_info_set_priority (THREAD_INFO_TYPE *info, MonoThreadPriority priority);
681 #endif /* __MONO_THREADS_H__ */