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>
27 typedef DWORD MonoNativeThreadId;
28 typedef HANDLE MonoNativeThreadHandle; /* unused */
30 typedef DWORD mono_native_thread_return_t;
31 typedef DWORD mono_thread_start_return_t;
33 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (tid)
34 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) ((MonoNativeThreadId)(tid))
36 typedef LPTHREAD_START_ROUTINE MonoThreadStart;
43 #include <mono/utils/mach-support.h>
45 typedef thread_port_t MonoNativeThreadHandle;
51 typedef pid_t MonoNativeThreadHandle;
53 #endif /* defined(__MACH__) */
55 typedef pthread_t MonoNativeThreadId;
57 typedef void* mono_native_thread_return_t;
58 typedef gsize mono_thread_start_return_t;
60 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (gsize)(tid)
61 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) (MonoNativeThreadId)(gsize)(tid)
63 typedef gsize (*MonoThreadStart)(gpointer);
65 #endif /* #ifdef HOST_WIN32 */
67 #ifndef MONO_INFINITE_WAIT
68 #define MONO_INFINITE_WAIT ((guint32) 0xFFFFFFFF)
77 THREAD_INFO_TYPE is a way to make the mono-threads module parametric - or sort of.
78 The GC using mono-threads might extend the MonoThreadInfo struct to add its own
79 data, this avoid a pointer indirection on what is on a lot of hot paths.
81 But extending MonoThreadInfo has de disavantage that all functions here return type
82 would require a cast, something like the following:
90 ((MyThreadInfo*)mono_thread_info_current ())->stuff = 1;
92 While porting sgen to use mono-threads, the number of casts required was too much and
93 code ended up looking horrible. So we use this cute little hack. The idea is that
94 whomever is including this header can set the expected type to be used by functions here
95 and reduce the number of casts drastically.
98 #ifndef THREAD_INFO_TYPE
99 #define THREAD_INFO_TYPE MonoThreadInfo
102 /* Mono Threads internal configuration knows*/
104 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
105 // #define USE_SIGNALS_ON_MACH
107 #if defined (_POSIX_VERSION) || defined (__native_client__)
108 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
109 #define USE_MACH_BACKEND
111 #define USE_POSIX_BACKEND
114 #define USE_WINDOWS_BACKEND
116 #error "no backend support for current platform"
117 #endif /* defined (_POSIX_VERSION) || defined (__native_client__) */
120 STATE_STARTING = 0x00,
121 STATE_RUNNING = 0x01,
122 STATE_DETACHED = 0x02,
124 STATE_ASYNC_SUSPENDED = 0x03,
125 STATE_SELF_SUSPENDED = 0x04,
126 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
127 STATE_SELF_SUSPEND_REQUESTED = 0x06,
128 STATE_BLOCKING = 0x07,
129 STATE_BLOCKING_AND_SUSPENDED = 0x8,
133 THREAD_STATE_MASK = 0x00FF,
134 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
135 THREAD_SUSPEND_COUNT_SHIFT = 8,
136 THREAD_SUSPEND_COUNT_MAX = 0xFF,
138 SELF_SUSPEND_STATE_INDEX = 0,
139 ASYNC_SUSPEND_STATE_INDEX = 1,
142 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
145 MonoLinkedListSetNode node;
146 guint32 small_id; /*Used by hazard pointers */
147 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
150 /*Tells if this thread was created by the runtime or not.*/
151 gboolean runtime_thread;
153 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
154 gboolean tools_thread;
156 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
157 void *stack_start_limit, *stack_end;
159 /* suspend machinery, fields protected by suspend_semaphore */
160 MonoSemType suspend_semaphore;
163 MonoSemType resume_semaphore;
165 /* only needed by the posix backend */
166 #if defined(USE_POSIX_BACKEND)
167 MonoSemType finish_resume_semaphore;
168 gboolean syscall_break_signal;
172 gboolean suspend_can_continue;
174 /* This memory pool is used by coop GC to save stack data roots between GC unsafe regions */
175 GByteArray *stackdata;
177 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
178 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
180 /*async call machinery, thread MUST be suspended before accessing those fields*/
181 void (*async_target)(void*);
185 If true, this thread is running a critical region of code and cannot be suspended.
186 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
187 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
189 gboolean inside_critical_region;
192 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
193 * operations like locking without having to pass an 'async' parameter around.
195 gboolean is_async_context;
198 * Values of TLS variables for this thread.
199 * This can be used to obtain the values of TLS variable for threads
200 * other than the current one.
202 gpointer tls [TLS_KEY_NUM];
204 /* IO layer handle for this thread */
205 /* Set when the thread is started, or in _wapi_thread_duplicate () */
206 MonoThreadHandle *handle;
210 MonoThreadInfoInterruptToken *interrupt_token;
212 /* HandleStack for coop handles */
213 gpointer handle_stack;
215 /* Stack mark for targets that explicitly require one */
220 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
222 This callback is called with @info still on the thread list.
223 This call is made while holding the suspend lock, so don't do callbacks.
224 SMR remains functional as its small_id has not been reclaimed.
226 void (*thread_unregister)(THREAD_INFO_TYPE *info);
228 This callback is called right before thread_unregister. This is called
229 without any locks held so it's the place for complicated cleanup.
231 The thread must remain operational between this call and thread_unregister.
232 It must be possible to successfully suspend it after thread_unregister completes.
234 void (*thread_detach)(THREAD_INFO_TYPE *info);
235 void (*thread_attach)(THREAD_INFO_TYPE *info);
236 gboolean (*mono_method_is_critical) (void *method);
237 gboolean (*ip_in_critical_region) (MonoDomain *domain, gpointer ip);
238 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
239 } MonoThreadInfoCallbacks;
242 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
243 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
244 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
245 void (*thread_state_init) (MonoThreadUnwindState *tctx);
246 } MonoThreadInfoRuntimeCallbacks;
248 //Not using 0 and 1 to ensure callbacks are not returning bad data
250 MonoResumeThread = 0x1234,
251 KeepSuspended = 0x4321,
252 } SuspendThreadResult;
254 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
256 static inline gboolean
257 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
259 return !((MonoThreadInfo*)info)->tools_thread;
263 Requires the world to be stoped
265 #define FOREACH_THREAD(thread) \
266 MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
268 #define FOREACH_THREAD_END \
274 #define FOREACH_THREAD_SAFE(thread) \
275 MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
277 #define FOREACH_THREAD_SAFE_END \
278 MONO_LLS_FOREACH_SAFE_END
280 static inline MonoNativeThreadId
281 mono_thread_info_get_tid (THREAD_INFO_TYPE *info)
283 return MONO_UINT_TO_NATIVE_THREAD_ID (((MonoThreadInfo*) info)->node.key);
287 mono_thread_info_set_tid (THREAD_INFO_TYPE *info, MonoNativeThreadId tid)
289 ((MonoThreadInfo*) info)->node.key = (uintptr_t) MONO_NATIVE_THREAD_ID_TO_UINT (tid);
293 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
294 * a single block with info from both camps.
297 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
300 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
302 MonoThreadInfoRuntimeCallbacks *
303 mono_threads_get_runtime_callbacks (void);
306 mono_thread_info_register_small_id (void);
309 mono_thread_info_attach (void *baseptr);
312 mono_thread_info_detach (void);
315 mono_thread_info_is_exiting (void);
318 mono_thread_info_current (void);
321 mono_thread_info_current_unchecked (void);
324 mono_thread_info_get_small_id (void);
327 mono_thread_info_list_head (void);
330 mono_thread_info_lookup (MonoNativeThreadId id);
333 mono_thread_info_resume (MonoNativeThreadId tid);
336 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
339 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
342 mono_thread_info_suspend_lock (void);
345 mono_thread_info_suspend_unlock (void);
348 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
351 mono_thread_info_set_is_async_context (gboolean async_context);
354 mono_thread_info_is_async_context (void);
357 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
360 mono_thread_info_yield (void);
363 mono_thread_info_sleep (guint32 ms, gboolean *alerted);
366 mono_thread_info_usleep (guint64 us);
369 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
372 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
375 mono_thread_info_exit (gsize exit_code);
378 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
381 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
383 MonoThreadInfoInterruptToken*
384 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
387 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
390 mono_thread_info_self_interrupt (void);
393 mono_thread_info_clear_self_interrupt (void);
396 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
399 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
402 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
405 mono_threads_create_thread (MonoThreadStart start, gpointer arg, gsize * const stack_size, MonoNativeThreadId *out_tid);
408 mono_threads_get_max_stack_size (void);
411 mono_threads_open_thread_handle (MonoThreadHandle *handle);
414 mono_threads_close_thread_handle (MonoThreadHandle *handle);
417 mono_threads_attach_tools_thread (void);
420 #if !defined(HOST_WIN32)
422 /*Use this instead of pthread_kill */
424 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
426 #endif /* !defined(HOST_WIN32) */
428 /* Internal API between mono-threads and its backends. */
430 /* Backend functions - a backend must implement all of the following */
432 This is called very early in the runtime, it cannot access any runtime facilities.
435 void mono_threads_suspend_init (void); //ok
437 void mono_threads_suspend_init_signals (void);
439 void mono_threads_coop_init (void);
442 This begins async suspend. This function must do the following:
444 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
445 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
446 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
448 If begin suspend fails the thread must be left uninterrupted and resumed.
450 gboolean mono_threads_suspend_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
453 This verifies the outcome of an async suspend operation.
455 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
456 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
458 gboolean mono_threads_suspend_check_suspend_result (THREAD_INFO_TYPE *info);
461 This begins async resume. This function must do the following:
463 - Install an async target if one was requested.
464 - Notify the target to resume.
465 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
467 gboolean mono_threads_suspend_begin_async_resume (THREAD_INFO_TYPE *info);
469 void mono_threads_suspend_register (THREAD_INFO_TYPE *info); //ok
470 void mono_threads_suspend_free (THREAD_INFO_TYPE *info);
471 void mono_threads_suspend_abort_syscall (THREAD_INFO_TYPE *info);
472 gboolean mono_threads_suspend_needs_abort_syscall (void);
473 gint mono_threads_suspend_search_alternative_signal (void);
474 gint mono_threads_suspend_get_suspend_signal (void);
475 gint mono_threads_suspend_get_restart_signal (void);
476 gint mono_threads_suspend_get_abort_signal (void);
478 int mono_threads_platform_create_thread (MonoThreadStart thread_fn, gpointer thread_data, gsize* const stack_size, MonoNativeThreadId *out_tid);
479 void mono_threads_platform_get_stack_bounds (guint8 **staddr, size_t *stsize);
480 gboolean mono_threads_platform_yield (void);
481 void mono_threads_platform_exit (gsize exit_code);
483 void mono_threads_coop_begin_global_suspend (void);
484 void mono_threads_coop_end_global_suspend (void);
486 MONO_API MonoNativeThreadId
487 mono_native_thread_id_get (void);
490 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
493 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
496 mono_native_thread_set_name (MonoNativeThreadId tid, const char *name);
499 mono_native_thread_join (MonoNativeThreadId tid);
501 /*Mach specific internals */
502 void mono_threads_init_dead_letter (void);
503 void mono_threads_install_dead_letter (void);
505 /* mono-threads internal API used by the backends. */
507 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
509 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
511 This tells the resume initiator that we completed resume duties and will return to runnable state.
513 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
516 This tells the resume initiator that we completed abort duties and will return to previous state.
518 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
520 /* Thread state machine functions */
525 ResumeInitSelfResume,
526 ResumeInitAsyncResume,
527 ResumeInitBlockingResume,
533 SelfSuspendNotifyAndWait,
534 } MonoSelfSupendResult;
537 AsyncSuspendAlreadySuspended,
539 AsyncSuspendInitSuspend,
540 AsyncSuspendBlocking,
541 } MonoRequestAsyncSuspendResult;
544 DoBlockingContinue, //in blocking mode, continue
545 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
546 } MonoDoBlockingResult;
549 DoneBlockingOk, //exited blocking fine
550 DoneBlockingWait, //thread should end suspended
551 } MonoDoneBlockingResult;
555 AbortBlockingIgnore, //Ignore
556 AbortBlockingIgnoreAndPoll, //Ignore and poll
557 AbortBlockingOk, //Abort worked
558 AbortBlockingWait, //Abort worked, but should wait for resume
559 } MonoAbortBlockingResult;
562 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
563 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
564 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
565 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
566 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
567 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
568 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
569 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
570 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
572 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
575 mono_threads_enter_gc_unsafe_region_cookie (void);
578 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
579 /* Advanced suspend API, used for suspending multiple threads as once. */
580 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
581 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
582 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
583 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
584 const char* mono_thread_state_name (int state);
586 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
587 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
588 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
590 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
591 gboolean mono_threads_wait_pending_operations (void);
592 void mono_threads_begin_global_suspend (void);
593 void mono_threads_end_global_suspend (void);
596 mono_thread_info_is_current (THREAD_INFO_TYPE *info);
599 MONO_THREAD_INFO_WAIT_RET_SUCCESS_0 = 0,
600 MONO_THREAD_INFO_WAIT_RET_ALERTED = -1,
601 MONO_THREAD_INFO_WAIT_RET_TIMEOUT = -2,
602 MONO_THREAD_INFO_WAIT_RET_FAILED = -3,
603 } MonoThreadInfoWaitRet;
605 MonoThreadInfoWaitRet
606 mono_thread_info_wait_one_handle (MonoThreadHandle *handle, guint32 timeout, gboolean alertable);
608 MonoThreadInfoWaitRet
609 mono_thread_info_wait_multiple_handle (MonoThreadHandle **thread_handles, gsize nhandles, MonoOSEvent *background_change_event, gboolean waitall, guint32 timeout, gboolean alertable);
611 #endif /* __MONO_THREADS_H__ */