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>
18 #include <mono/utils/os-event.h>
19 #include <mono/utils/refcount.h>
21 #include <mono/io-layer/io-layer.h>
29 typedef DWORD MonoNativeThreadId;
30 typedef HANDLE MonoNativeThreadHandle; /* unused */
32 typedef DWORD mono_native_thread_return_t;
33 typedef DWORD mono_thread_start_return_t;
35 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (tid)
36 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) ((MonoNativeThreadId)(tid))
38 typedef LPTHREAD_START_ROUTINE MonoThreadStart;
45 #include <mono/utils/mach-support.h>
47 typedef thread_port_t MonoNativeThreadHandle;
53 typedef pid_t MonoNativeThreadHandle;
55 #endif /* defined(__MACH__) */
57 typedef pthread_t MonoNativeThreadId;
59 typedef void* mono_native_thread_return_t;
60 typedef gsize mono_thread_start_return_t;
62 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (gsize)(tid)
63 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) (MonoNativeThreadId)(gsize)(tid)
65 typedef gsize (*MonoThreadStart)(gpointer);
67 #endif /* #ifdef HOST_WIN32 */
75 THREAD_INFO_TYPE is a way to make the mono-threads module parametric - or sort of.
76 The GC using mono-threads might extend the MonoThreadInfo struct to add its own
77 data, this avoid a pointer indirection on what is on a lot of hot paths.
79 But extending MonoThreadInfo has de disavantage that all functions here return type
80 would require a cast, something like the following:
88 ((MyThreadInfo*)mono_thread_info_current ())->stuff = 1;
90 While porting sgen to use mono-threads, the number of casts required was too much and
91 code ended up looking horrible. So we use this cute little hack. The idea is that
92 whomever is including this header can set the expected type to be used by functions here
93 and reduce the number of casts drastically.
96 #ifndef THREAD_INFO_TYPE
97 #define THREAD_INFO_TYPE MonoThreadInfo
100 /* Mono Threads internal configuration knows*/
102 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
103 // #define USE_SIGNALS_ON_MACH
105 #if defined (_POSIX_VERSION) || defined (__native_client__)
106 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
107 #define USE_MACH_BACKEND
109 #define USE_POSIX_BACKEND
112 #define USE_WINDOWS_BACKEND
114 #error "no backend support for current platform"
115 #endif /* defined (_POSIX_VERSION) || defined (__native_client__) */
118 STATE_STARTING = 0x00,
119 STATE_RUNNING = 0x01,
120 STATE_DETACHED = 0x02,
122 STATE_ASYNC_SUSPENDED = 0x03,
123 STATE_SELF_SUSPENDED = 0x04,
124 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
125 STATE_SELF_SUSPEND_REQUESTED = 0x06,
126 STATE_BLOCKING = 0x07,
127 STATE_BLOCKING_AND_SUSPENDED = 0x8,
131 THREAD_STATE_MASK = 0x00FF,
132 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
133 THREAD_SUSPEND_COUNT_SHIFT = 8,
134 THREAD_SUSPEND_COUNT_MAX = 0xFF,
136 SELF_SUSPEND_STATE_INDEX = 0,
137 ASYNC_SUSPEND_STATE_INDEX = 1,
140 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
143 MonoLinkedListSetNode node;
144 guint32 small_id; /*Used by hazard pointers */
145 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
148 /*Tells if this thread was created by the runtime or not.*/
149 gboolean runtime_thread;
151 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
152 gboolean tools_thread;
154 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
155 void *stack_start_limit, *stack_end;
157 /* suspend machinery, fields protected by suspend_semaphore */
158 MonoSemType suspend_semaphore;
161 MonoSemType resume_semaphore;
163 /* only needed by the posix backend */
164 #if defined(USE_POSIX_BACKEND)
165 MonoSemType finish_resume_semaphore;
166 gboolean syscall_break_signal;
170 gboolean suspend_can_continue;
172 /* This memory pool is used by coop GC to save stack data roots between GC unsafe regions */
173 GByteArray *stackdata;
175 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
176 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
178 /*async call machinery, thread MUST be suspended before accessing those fields*/
179 void (*async_target)(void*);
183 If true, this thread is running a critical region of code and cannot be suspended.
184 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
185 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
187 gboolean inside_critical_region;
190 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
191 * operations like locking without having to pass an 'async' parameter around.
193 gboolean is_async_context;
196 * Values of TLS variables for this thread.
197 * This can be used to obtain the values of TLS variable for threads
198 * other than the current one.
200 gpointer tls [TLS_KEY_NUM];
202 /* IO layer handle for this thread */
203 /* Set when the thread is started, or in _wapi_thread_duplicate () */
204 MonoThreadHandle *handle;
208 MonoThreadInfoInterruptToken *interrupt_token;
210 /* HandleStack for coop handles */
211 gpointer handle_stack;
213 /* Stack mark for targets that explicitly require one */
218 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
220 This callback is called with @info still on the thread list.
221 This call is made while holding the suspend lock, so don't do callbacks.
222 SMR remains functional as its small_id has not been reclaimed.
224 void (*thread_unregister)(THREAD_INFO_TYPE *info);
226 This callback is called right before thread_unregister. This is called
227 without any locks held so it's the place for complicated cleanup.
229 The thread must remain operational between this call and thread_unregister.
230 It must be possible to successfully suspend it after thread_unregister completes.
232 void (*thread_detach)(THREAD_INFO_TYPE *info);
233 void (*thread_attach)(THREAD_INFO_TYPE *info);
234 gboolean (*mono_method_is_critical) (void *method);
235 gboolean (*ip_in_critical_region) (MonoDomain *domain, gpointer ip);
236 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
237 } MonoThreadInfoCallbacks;
240 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
241 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
242 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
243 void (*thread_state_init) (MonoThreadUnwindState *tctx);
244 } MonoThreadInfoRuntimeCallbacks;
246 //Not using 0 and 1 to ensure callbacks are not returning bad data
248 MonoResumeThread = 0x1234,
249 KeepSuspended = 0x4321,
250 } SuspendThreadResult;
252 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
254 static inline gboolean
255 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
257 return !((MonoThreadInfo*)info)->tools_thread;
261 Requires the world to be stoped
263 #define FOREACH_THREAD(thread) \
264 MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
266 #define FOREACH_THREAD_END \
272 #define FOREACH_THREAD_SAFE(thread) \
273 MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
275 #define FOREACH_THREAD_SAFE_END \
276 MONO_LLS_FOREACH_SAFE_END
278 static inline MonoNativeThreadId
279 mono_thread_info_get_tid (THREAD_INFO_TYPE *info)
281 return MONO_UINT_TO_NATIVE_THREAD_ID (((MonoThreadInfo*) info)->node.key);
285 mono_thread_info_set_tid (THREAD_INFO_TYPE *info, MonoNativeThreadId tid)
287 ((MonoThreadInfo*) info)->node.key = (uintptr_t) MONO_NATIVE_THREAD_ID_TO_UINT (tid);
291 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
292 * a single block with info from both camps.
295 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
298 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
300 MonoThreadInfoRuntimeCallbacks *
301 mono_threads_get_runtime_callbacks (void);
304 mono_thread_info_register_small_id (void);
307 mono_thread_info_attach (void *baseptr);
310 mono_thread_info_detach (void);
313 mono_thread_info_is_exiting (void);
316 mono_thread_info_current (void);
319 mono_thread_info_current_unchecked (void);
322 mono_thread_info_get_small_id (void);
325 mono_thread_info_list_head (void);
328 mono_thread_info_lookup (MonoNativeThreadId id);
331 mono_thread_info_resume (MonoNativeThreadId tid);
334 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
337 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
340 mono_thread_info_suspend_lock (void);
343 mono_thread_info_suspend_unlock (void);
346 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
349 mono_thread_info_set_is_async_context (gboolean async_context);
352 mono_thread_info_is_async_context (void);
355 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
358 mono_thread_info_yield (void);
361 mono_thread_info_sleep (guint32 ms, gboolean *alerted);
364 mono_thread_info_usleep (guint64 us);
367 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
370 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
373 mono_thread_info_exit (gsize exit_code);
376 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
379 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
381 MonoThreadInfoInterruptToken*
382 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
385 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
388 mono_thread_info_self_interrupt (void);
391 mono_thread_info_clear_self_interrupt (void);
394 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
397 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
400 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
403 mono_threads_create_thread (MonoThreadStart start, gpointer arg, gsize * const stack_size, MonoNativeThreadId *out_tid);
406 mono_threads_get_max_stack_size (void);
409 mono_threads_open_thread_handle (MonoThreadHandle *handle);
412 mono_threads_close_thread_handle (MonoThreadHandle *handle);
415 mono_threads_attach_tools_thread (void);
418 #if !defined(HOST_WIN32)
420 /*Use this instead of pthread_kill */
422 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
424 #endif /* !defined(HOST_WIN32) */
426 /* Internal API between mono-threads and its backends. */
428 /* Backend functions - a backend must implement all of the following */
430 This is called very early in the runtime, it cannot access any runtime facilities.
433 void mono_threads_suspend_init (void); //ok
435 void mono_threads_suspend_init_signals (void);
437 void mono_threads_coop_init (void);
440 This begins async suspend. This function must do the following:
442 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
443 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
444 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
446 If begin suspend fails the thread must be left uninterrupted and resumed.
448 gboolean mono_threads_suspend_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
451 This verifies the outcome of an async suspend operation.
453 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
454 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
456 gboolean mono_threads_suspend_check_suspend_result (THREAD_INFO_TYPE *info);
459 This begins async resume. This function must do the following:
461 - Install an async target if one was requested.
462 - Notify the target to resume.
463 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
465 gboolean mono_threads_suspend_begin_async_resume (THREAD_INFO_TYPE *info);
467 void mono_threads_suspend_register (THREAD_INFO_TYPE *info); //ok
468 void mono_threads_suspend_free (THREAD_INFO_TYPE *info);
469 void mono_threads_suspend_abort_syscall (THREAD_INFO_TYPE *info);
470 gboolean mono_threads_suspend_needs_abort_syscall (void);
471 gint mono_threads_suspend_search_alternative_signal (void);
472 gint mono_threads_suspend_get_suspend_signal (void);
473 gint mono_threads_suspend_get_restart_signal (void);
474 gint mono_threads_suspend_get_abort_signal (void);
476 int mono_threads_platform_create_thread (MonoThreadStart thread_fn, gpointer thread_data, gsize* const stack_size, MonoNativeThreadId *out_tid);
477 void mono_threads_platform_get_stack_bounds (guint8 **staddr, size_t *stsize);
478 gboolean mono_threads_platform_yield (void);
479 void mono_threads_platform_exit (gsize exit_code);
481 void mono_threads_coop_begin_global_suspend (void);
482 void mono_threads_coop_end_global_suspend (void);
484 MONO_API MonoNativeThreadId
485 mono_native_thread_id_get (void);
488 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
491 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
494 mono_native_thread_set_name (MonoNativeThreadId tid, const char *name);
497 mono_native_thread_join (MonoNativeThreadId tid);
499 /*Mach specific internals */
500 void mono_threads_init_dead_letter (void);
501 void mono_threads_install_dead_letter (void);
503 /* mono-threads internal API used by the backends. */
505 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
507 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
509 This tells the resume initiator that we completed resume duties and will return to runnable state.
511 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
514 This tells the resume initiator that we completed abort duties and will return to previous state.
516 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
518 /* Thread state machine functions */
523 ResumeInitSelfResume,
524 ResumeInitAsyncResume,
525 ResumeInitBlockingResume,
531 SelfSuspendNotifyAndWait,
532 } MonoSelfSupendResult;
535 AsyncSuspendAlreadySuspended,
537 AsyncSuspendInitSuspend,
538 AsyncSuspendBlocking,
539 } MonoRequestAsyncSuspendResult;
542 DoBlockingContinue, //in blocking mode, continue
543 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
544 } MonoDoBlockingResult;
547 DoneBlockingOk, //exited blocking fine
548 DoneBlockingWait, //thread should end suspended
549 } MonoDoneBlockingResult;
553 AbortBlockingIgnore, //Ignore
554 AbortBlockingIgnoreAndPoll, //Ignore and poll
555 AbortBlockingOk, //Abort worked
556 AbortBlockingWait, //Abort worked, but should wait for resume
557 } MonoAbortBlockingResult;
560 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
561 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
562 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
563 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
564 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
565 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
566 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
567 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
568 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
570 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
573 mono_threads_enter_gc_unsafe_region_cookie (void);
576 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
577 /* Advanced suspend API, used for suspending multiple threads as once. */
578 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
579 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
580 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
581 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
582 const char* mono_thread_state_name (int state);
584 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
585 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
586 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
588 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
589 gboolean mono_threads_wait_pending_operations (void);
590 void mono_threads_begin_global_suspend (void);
591 void mono_threads_end_global_suspend (void);
594 mono_thread_info_is_current (THREAD_INFO_TYPE *info);
597 MONO_THREAD_INFO_WAIT_RET_SUCCESS_0 = 0,
598 MONO_THREAD_INFO_WAIT_RET_ALERTED = -1,
599 MONO_THREAD_INFO_WAIT_RET_TIMEOUT = -2,
600 MONO_THREAD_INFO_WAIT_RET_FAILED = -3,
601 } MonoThreadInfoWaitRet;
603 MonoThreadInfoWaitRet
604 mono_thread_info_wait_one_handle (MonoThreadHandle *handle, guint32 timeout, gboolean alertable);
606 MonoThreadInfoWaitRet
607 mono_thread_info_wait_multiple_handle (MonoThreadHandle **thread_handles, gsize nhandles, MonoOSEvent *background_change_event, gboolean waitall, guint32 timeout, gboolean alertable);
609 #endif /* __MONO_THREADS_H__ */