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))
35 typedef LPTHREAD_START_ROUTINE MonoThreadStart;
42 #include <mono/utils/mach-support.h>
44 typedef thread_port_t MonoNativeThreadHandle;
50 typedef pid_t MonoNativeThreadHandle;
52 #endif /* defined(__MACH__) */
54 typedef pthread_t MonoNativeThreadId;
56 typedef void* mono_native_thread_return_t;
58 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (gsize)(tid)
59 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) (MonoNativeThreadId)(gsize)(tid)
61 typedef gsize (*MonoThreadStart)(gpointer);
63 #endif /* #ifdef HOST_WIN32 */
66 THREAD_INFO_TYPE is a way to make the mono-threads module parametric - or sort of.
67 The GC using mono-threads might extend the MonoThreadInfo struct to add its own
68 data, this avoid a pointer indirection on what is on a lot of hot paths.
70 But extending MonoThreadInfo has de disavantage that all functions here return type
71 would require a cast, something like the following:
79 ((MyThreadInfo*)mono_thread_info_current ())->stuff = 1;
81 While porting sgen to use mono-threads, the number of casts required was too much and
82 code ended up looking horrible. So we use this cute little hack. The idea is that
83 whomever is including this header can set the expected type to be used by functions here
84 and reduce the number of casts drastically.
87 #ifndef THREAD_INFO_TYPE
88 #define THREAD_INFO_TYPE MonoThreadInfo
91 /* Mono Threads internal configuration knows*/
93 /* Logging - enable them below if you need specific logging for the category you need */
94 #define MOSTLY_ASYNC_SAFE_PRINTF(...) do { \
95 char __buff[1024]; __buff [0] = '\0'; \
96 g_snprintf (__buff, sizeof (__buff), __VA_ARGS__); \
97 write (1, __buff, strlen (__buff)); \
102 #define THREADS_DEBUG(...)
104 #define THREADS_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
108 #define THREADS_STW_DEBUG(...)
110 #define THREADS_STW_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
114 #define THREADS_SUSPEND_DEBUG(...)
116 #define THREADS_SUSPEND_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
120 #define THREADS_STATE_MACHINE_DEBUG(...)
122 #define THREADS_STATE_MACHINE_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
126 #define THREADS_INTERRUPT_DEBUG(...)
128 #define THREADS_INTERRUPT_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
131 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
132 // #define USE_SIGNALS_ON_MACH
134 #if defined (_POSIX_VERSION) || defined (__native_client__)
135 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
136 #define USE_MACH_BACKEND
138 #define USE_POSIX_BACKEND
141 #define USE_WINDOWS_BACKEND
143 #error "no backend support for current platform"
144 #endif /* defined (_POSIX_VERSION) || defined (__native_client__) */
147 STATE_STARTING = 0x00,
148 STATE_RUNNING = 0x01,
149 STATE_DETACHED = 0x02,
151 STATE_ASYNC_SUSPENDED = 0x03,
152 STATE_SELF_SUSPENDED = 0x04,
153 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
154 STATE_SELF_SUSPEND_REQUESTED = 0x06,
155 STATE_BLOCKING = 0x07,
156 STATE_BLOCKING_AND_SUSPENDED = 0x8,
160 THREAD_STATE_MASK = 0x00FF,
161 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
162 THREAD_SUSPEND_COUNT_SHIFT = 8,
163 THREAD_SUSPEND_COUNT_MAX = 0xFF,
165 SELF_SUSPEND_STATE_INDEX = 0,
166 ASYNC_SUSPEND_STATE_INDEX = 1,
169 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
172 MonoLinkedListSetNode node;
173 guint32 small_id; /*Used by hazard pointers */
174 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
177 /*Tells if this thread was created by the runtime or not.*/
178 gboolean runtime_thread;
180 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
181 gboolean tools_thread;
183 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
184 void *stack_start_limit, *stack_end;
186 /* suspend machinery, fields protected by suspend_semaphore */
187 MonoSemType suspend_semaphore;
190 MonoSemType resume_semaphore;
192 /* only needed by the posix backend */
193 #if defined(USE_POSIX_BACKEND)
194 MonoSemType finish_resume_semaphore;
195 gboolean syscall_break_signal;
199 gboolean suspend_can_continue;
201 /* This memory pool is used by coop GC to save stack data roots between GC unsafe regions */
202 GByteArray *stackdata;
204 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
205 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
207 /*async call machinery, thread MUST be suspended before accessing those fields*/
208 void (*async_target)(void*);
212 If true, this thread is running a critical region of code and cannot be suspended.
213 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
214 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
216 gboolean inside_critical_region;
219 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
220 * operations like locking without having to pass an 'async' parameter around.
222 gboolean is_async_context;
225 * Values of TLS variables for this thread.
226 * This can be used to obtain the values of TLS variable for threads
227 * other than the current one.
229 gpointer tls [TLS_KEY_NUM];
231 /* IO layer handle for this thread */
232 /* Set when the thread is started, or in _wapi_thread_duplicate () */
237 MonoThreadInfoInterruptToken *interrupt_token;
239 /* HandleStack for coop handles */
240 gpointer handle_stack;
242 /* Stack mark for targets that explicitly require one */
245 #if defined(_POSIX_VERSION) || defined(__native_client__)
246 /* This is the data that was stored in the w32 handle */
247 GPtrArray *owned_mutexes;
253 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
255 This callback is called with @info still on the thread list.
256 This call is made while holding the suspend lock, so don't do callbacks.
257 SMR remains functional as its small_id has not been reclaimed.
259 void (*thread_unregister)(THREAD_INFO_TYPE *info);
261 This callback is called right before thread_unregister. This is called
262 without any locks held so it's the place for complicated cleanup.
264 The thread must remain operational between this call and thread_unregister.
265 It must be possible to successfully suspend it after thread_unregister completes.
267 void (*thread_detach)(THREAD_INFO_TYPE *info);
268 void (*thread_attach)(THREAD_INFO_TYPE *info);
269 gboolean (*mono_method_is_critical) (void *method);
270 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
271 } MonoThreadInfoCallbacks;
274 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
275 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
276 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
277 void (*thread_state_init) (MonoThreadUnwindState *tctx);
278 } MonoThreadInfoRuntimeCallbacks;
280 //Not using 0 and 1 to ensure callbacks are not returning bad data
282 MonoResumeThread = 0x1234,
283 KeepSuspended = 0x4321,
284 } SuspendThreadResult;
286 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
289 * Parameters to pass for thread creation
293 guint32 creation_flags;
298 MONO_THREAD_PRIORITY_LOWEST = 0,
299 MONO_THREAD_PRIORITY_BELOW_NORMAL = 1,
300 MONO_THREAD_PRIORITY_NORMAL = 2,
301 MONO_THREAD_PRIORITY_ABOVE_NORMAL = 3,
302 MONO_THREAD_PRIORITY_HIGHEST = 4,
303 } MonoThreadPriority;
305 static inline gboolean
306 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
308 return !((MonoThreadInfo*)info)->tools_thread;
312 Requires the world to be stoped
314 #define FOREACH_THREAD(thread) \
315 MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
317 #define FOREACH_THREAD_END \
323 #define FOREACH_THREAD_SAFE(thread) \
324 MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
326 #define FOREACH_THREAD_SAFE_END \
327 MONO_LLS_FOREACH_SAFE_END
329 static inline MonoNativeThreadId
330 mono_thread_info_get_tid (THREAD_INFO_TYPE *info)
332 return MONO_UINT_TO_NATIVE_THREAD_ID (((MonoThreadInfo*) info)->node.key);
336 mono_thread_info_set_tid (THREAD_INFO_TYPE *info, MonoNativeThreadId tid)
338 ((MonoThreadInfo*) info)->node.key = (uintptr_t) MONO_NATIVE_THREAD_ID_TO_UINT (tid);
342 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
343 * a single block with info from both camps.
346 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
349 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
351 MonoThreadInfoRuntimeCallbacks *
352 mono_threads_get_runtime_callbacks (void);
355 mono_thread_info_register_small_id (void);
358 mono_thread_info_attach (void *baseptr);
361 mono_thread_info_detach (void);
364 mono_thread_info_is_exiting (void);
367 mono_thread_info_current (void);
370 mono_thread_info_current_unchecked (void);
373 mono_thread_info_get_small_id (void);
376 mono_thread_info_list_head (void);
379 mono_thread_info_lookup (MonoNativeThreadId id);
382 mono_thread_info_resume (MonoNativeThreadId tid);
385 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
387 //XXX new API, fix the world
389 mono_thread_info_begin_self_suspend (void);
392 mono_thread_info_end_self_suspend (void);
397 mono_thread_info_unified_management_enabled (void);
400 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
403 mono_thread_info_suspend_lock (void);
406 mono_thread_info_suspend_unlock (void);
409 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
412 mono_thread_info_set_is_async_context (gboolean async_context);
415 mono_thread_info_is_async_context (void);
418 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
421 mono_thread_info_yield (void);
424 mono_thread_info_sleep (guint32 ms, gboolean *alerted);
427 mono_thread_info_usleep (guint64 us);
430 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
433 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
436 mono_thread_info_exit (void);
439 mono_thread_info_set_exited (THREAD_INFO_TYPE *info);
442 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
445 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
447 MonoThreadInfoInterruptToken*
448 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
451 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
454 mono_thread_info_self_interrupt (void);
457 mono_thread_info_clear_self_interrupt (void);
460 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
463 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
466 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
469 mono_threads_create_thread (MonoThreadStart start, gpointer arg, MonoThreadParm *tp, MonoNativeThreadId *out_tid);
472 mono_threads_get_max_stack_size (void);
475 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
478 mono_threads_close_thread_handle (HANDLE handle);
481 mono_threads_attach_tools_thread (void);
484 #if !defined(HOST_WIN32)
486 /*Use this instead of pthread_kill */
488 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
490 #endif /* !defined(HOST_WIN32) */
492 /* Internal API between mono-threads and its backends. */
494 /* Backend functions - a backend must implement all of the following */
496 This is called very early in the runtime, it cannot access any runtime facilities.
499 void mono_threads_suspend_init (void); //ok
501 void mono_threads_platform_init (void);
503 void mono_threads_coop_init (void);
505 void mono_threads_abort_syscall_init (void);
508 This begins async suspend. This function must do the following:
510 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
511 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
512 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
514 If begin suspend fails the thread must be left uninterrupted and resumed.
516 gboolean mono_threads_suspend_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
519 This verifies the outcome of an async suspend operation.
521 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
522 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
524 gboolean mono_threads_suspend_check_suspend_result (THREAD_INFO_TYPE *info);
527 This begins async resume. This function must do the following:
529 - Install an async target if one was requested.
530 - Notify the target to resume.
531 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
533 gboolean mono_threads_suspend_begin_async_resume (THREAD_INFO_TYPE *info);
535 void mono_threads_suspend_register (THREAD_INFO_TYPE *info); //ok
536 void mono_threads_suspend_free (THREAD_INFO_TYPE *info);
537 void mono_threads_suspend_abort_syscall (THREAD_INFO_TYPE *info);
538 gboolean mono_threads_suspend_needs_abort_syscall (void);
540 void mono_threads_platform_register (THREAD_INFO_TYPE *info);
541 void mono_threads_platform_unregister (THREAD_INFO_TYPE *info);
542 int mono_threads_platform_create_thread (MonoThreadStart thread_fn, gpointer thread_data, gsize stack_size, MonoNativeThreadId *out_tid);
543 void mono_threads_platform_get_stack_bounds (guint8 **staddr, size_t *stsize);
544 gboolean mono_threads_platform_yield (void);
545 void mono_threads_platform_exit (int exit_code);
546 HANDLE mono_threads_platform_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
547 void mono_threads_platform_close_thread_handle (HANDLE handle);
548 void mono_threads_platform_set_exited (THREAD_INFO_TYPE *info);
549 void mono_threads_platform_describe (THREAD_INFO_TYPE *info, GString *text);
550 void mono_threads_platform_own_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
551 void mono_threads_platform_disown_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
552 MonoThreadPriority mono_threads_platform_get_priority (THREAD_INFO_TYPE *info);
553 void mono_threads_platform_set_priority (THREAD_INFO_TYPE *info, MonoThreadPriority priority);
554 gpointer mono_threads_platform_duplicate_handle (THREAD_INFO_TYPE *info);
556 void mono_threads_coop_begin_global_suspend (void);
557 void mono_threads_coop_end_global_suspend (void);
559 MONO_API MonoNativeThreadId
560 mono_native_thread_id_get (void);
563 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
566 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
569 mono_native_thread_set_name (MonoNativeThreadId tid, const char *name);
571 /*Mach specific internals */
572 void mono_threads_init_dead_letter (void);
573 void mono_threads_install_dead_letter (void);
575 /* mono-threads internal API used by the backends. */
577 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
579 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
581 This tells the resume initiator that we completed resume duties and will return to runnable state.
583 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
586 This tells the resume initiator that we completed abort duties and will return to previous state.
588 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
590 /* Thread state machine functions */
595 ResumeInitSelfResume,
596 ResumeInitAsyncResume,
597 ResumeInitBlockingResume,
603 SelfSuspendNotifyAndWait,
604 } MonoSelfSupendResult;
607 AsyncSuspendAlreadySuspended,
609 AsyncSuspendInitSuspend,
610 AsyncSuspendBlocking,
611 } MonoRequestAsyncSuspendResult;
614 DoBlockingContinue, //in blocking mode, continue
615 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
616 } MonoDoBlockingResult;
619 DoneBlockingOk, //exited blocking fine
620 DoneBlockingWait, //thread should end suspended
621 } MonoDoneBlockingResult;
625 AbortBlockingIgnore, //Ignore
626 AbortBlockingIgnoreAndPoll, //Ignore and poll
627 AbortBlockingOk, //Abort worked
628 AbortBlockingWait, //Abort worked, but should wait for resume
629 } MonoAbortBlockingResult;
632 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
633 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
634 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
635 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
636 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
637 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
638 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
639 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
640 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
641 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
643 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
646 mono_threads_enter_gc_unsafe_region_cookie (void);
649 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
650 /* Advanced suspend API, used for suspending multiple threads as once. */
651 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
652 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
653 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
654 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
655 const char* mono_thread_state_name (int state);
657 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
658 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
659 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
661 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
662 gboolean mono_threads_wait_pending_operations (void);
663 void mono_threads_begin_global_suspend (void);
664 void mono_threads_end_global_suspend (void);
667 mono_thread_info_is_current (THREAD_INFO_TYPE *info);
670 mono_thread_info_duplicate_handle (THREAD_INFO_TYPE *info);
673 mono_thread_info_describe (THREAD_INFO_TYPE *info, GString *text);
676 mono_thread_info_own_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
679 mono_thread_info_disown_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
682 mono_thread_info_get_priority (THREAD_INFO_TYPE *info);
685 mono_thread_info_set_priority (THREAD_INFO_TYPE *info, MonoThreadPriority priority);
687 #endif /* __MONO_THREADS_H__ */