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 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
94 // #define USE_SIGNALS_ON_MACH
96 #if defined (_POSIX_VERSION) || defined (__native_client__)
97 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
98 #define USE_MACH_BACKEND
100 #define USE_POSIX_BACKEND
103 #define USE_WINDOWS_BACKEND
105 #error "no backend support for current platform"
106 #endif /* defined (_POSIX_VERSION) || defined (__native_client__) */
109 STATE_STARTING = 0x00,
110 STATE_RUNNING = 0x01,
111 STATE_DETACHED = 0x02,
113 STATE_ASYNC_SUSPENDED = 0x03,
114 STATE_SELF_SUSPENDED = 0x04,
115 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
116 STATE_SELF_SUSPEND_REQUESTED = 0x06,
117 STATE_BLOCKING = 0x07,
118 STATE_BLOCKING_AND_SUSPENDED = 0x8,
122 THREAD_STATE_MASK = 0x00FF,
123 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
124 THREAD_SUSPEND_COUNT_SHIFT = 8,
125 THREAD_SUSPEND_COUNT_MAX = 0xFF,
127 SELF_SUSPEND_STATE_INDEX = 0,
128 ASYNC_SUSPEND_STATE_INDEX = 1,
131 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
134 MonoLinkedListSetNode node;
135 guint32 small_id; /*Used by hazard pointers */
136 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
139 /*Tells if this thread was created by the runtime or not.*/
140 gboolean runtime_thread;
142 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
143 gboolean tools_thread;
145 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
146 void *stack_start_limit, *stack_end;
148 /* suspend machinery, fields protected by suspend_semaphore */
149 MonoSemType suspend_semaphore;
152 MonoSemType resume_semaphore;
154 /* only needed by the posix backend */
155 #if defined(USE_POSIX_BACKEND)
156 MonoSemType finish_resume_semaphore;
157 gboolean syscall_break_signal;
161 gboolean suspend_can_continue;
163 /* This memory pool is used by coop GC to save stack data roots between GC unsafe regions */
164 GByteArray *stackdata;
166 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
167 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
169 /*async call machinery, thread MUST be suspended before accessing those fields*/
170 void (*async_target)(void*);
174 If true, this thread is running a critical region of code and cannot be suspended.
175 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
176 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
178 gboolean inside_critical_region;
181 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
182 * operations like locking without having to pass an 'async' parameter around.
184 gboolean is_async_context;
187 * Values of TLS variables for this thread.
188 * This can be used to obtain the values of TLS variable for threads
189 * other than the current one.
191 gpointer tls [TLS_KEY_NUM];
193 /* IO layer handle for this thread */
194 /* Set when the thread is started, or in _wapi_thread_duplicate () */
199 MonoThreadInfoInterruptToken *interrupt_token;
201 /* HandleStack for coop handles */
202 gpointer handle_stack;
204 /* Stack mark for targets that explicitly require one */
209 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
211 This callback is called with @info still on the thread list.
212 This call is made while holding the suspend lock, so don't do callbacks.
213 SMR remains functional as its small_id has not been reclaimed.
215 void (*thread_unregister)(THREAD_INFO_TYPE *info);
217 This callback is called right before thread_unregister. This is called
218 without any locks held so it's the place for complicated cleanup.
220 The thread must remain operational between this call and thread_unregister.
221 It must be possible to successfully suspend it after thread_unregister completes.
223 void (*thread_detach)(THREAD_INFO_TYPE *info);
224 void (*thread_attach)(THREAD_INFO_TYPE *info);
225 gboolean (*mono_method_is_critical) (void *method);
226 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
227 } MonoThreadInfoCallbacks;
230 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
231 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
232 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
233 void (*thread_state_init) (MonoThreadUnwindState *tctx);
234 } MonoThreadInfoRuntimeCallbacks;
236 //Not using 0 and 1 to ensure callbacks are not returning bad data
238 MonoResumeThread = 0x1234,
239 KeepSuspended = 0x4321,
240 } SuspendThreadResult;
242 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
244 static inline gboolean
245 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
247 return !((MonoThreadInfo*)info)->tools_thread;
251 Requires the world to be stoped
253 #define FOREACH_THREAD(thread) \
254 MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
256 #define FOREACH_THREAD_END \
262 #define FOREACH_THREAD_SAFE(thread) \
263 MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
265 #define FOREACH_THREAD_SAFE_END \
266 MONO_LLS_FOREACH_SAFE_END
268 static inline MonoNativeThreadId
269 mono_thread_info_get_tid (THREAD_INFO_TYPE *info)
271 return MONO_UINT_TO_NATIVE_THREAD_ID (((MonoThreadInfo*) info)->node.key);
275 mono_thread_info_set_tid (THREAD_INFO_TYPE *info, MonoNativeThreadId tid)
277 ((MonoThreadInfo*) info)->node.key = (uintptr_t) MONO_NATIVE_THREAD_ID_TO_UINT (tid);
281 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
282 * a single block with info from both camps.
285 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
288 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
290 MonoThreadInfoRuntimeCallbacks *
291 mono_threads_get_runtime_callbacks (void);
294 mono_thread_info_register_small_id (void);
297 mono_thread_info_attach (void *baseptr);
300 mono_thread_info_detach (void);
303 mono_thread_info_is_exiting (void);
306 mono_thread_info_current (void);
309 mono_thread_info_current_unchecked (void);
312 mono_thread_info_get_small_id (void);
315 mono_thread_info_list_head (void);
318 mono_thread_info_lookup (MonoNativeThreadId id);
321 mono_thread_info_resume (MonoNativeThreadId tid);
324 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
326 //XXX new API, fix the world
328 mono_thread_info_begin_self_suspend (void);
331 mono_thread_info_end_self_suspend (void);
336 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
339 mono_thread_info_suspend_lock (void);
342 mono_thread_info_suspend_unlock (void);
345 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
348 mono_thread_info_set_is_async_context (gboolean async_context);
351 mono_thread_info_is_async_context (void);
354 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
357 mono_thread_info_yield (void);
360 mono_thread_info_sleep (guint32 ms, gboolean *alerted);
363 mono_thread_info_usleep (guint64 us);
366 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
369 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
372 mono_thread_info_exit (void);
375 mono_thread_info_set_exited (THREAD_INFO_TYPE *info);
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 (HANDLE handle, MonoNativeThreadId tid);
414 mono_threads_close_thread_handle (HANDLE 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_platform_init (void);
441 void mono_threads_coop_init (void);
444 This begins async suspend. This function must do the following:
446 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
447 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
448 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
450 If begin suspend fails the thread must be left uninterrupted and resumed.
452 gboolean mono_threads_suspend_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
455 This verifies the outcome of an async suspend operation.
457 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
458 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
460 gboolean mono_threads_suspend_check_suspend_result (THREAD_INFO_TYPE *info);
463 This begins async resume. This function must do the following:
465 - Install an async target if one was requested.
466 - Notify the target to resume.
467 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
469 gboolean mono_threads_suspend_begin_async_resume (THREAD_INFO_TYPE *info);
471 void mono_threads_suspend_register (THREAD_INFO_TYPE *info); //ok
472 void mono_threads_suspend_free (THREAD_INFO_TYPE *info);
473 void mono_threads_suspend_abort_syscall (THREAD_INFO_TYPE *info);
474 gboolean mono_threads_suspend_needs_abort_syscall (void);
475 gint mono_threads_suspend_search_alternative_signal (void);
476 gint mono_threads_suspend_get_suspend_signal (void);
477 gint mono_threads_suspend_get_restart_signal (void);
478 gint mono_threads_suspend_get_abort_signal (void);
480 void mono_threads_platform_register (THREAD_INFO_TYPE *info);
481 void mono_threads_platform_unregister (THREAD_INFO_TYPE *info);
482 int mono_threads_platform_create_thread (MonoThreadStart thread_fn, gpointer thread_data, gsize* const stack_size, MonoNativeThreadId *out_tid);
483 void mono_threads_platform_get_stack_bounds (guint8 **staddr, size_t *stsize);
484 gboolean mono_threads_platform_yield (void);
485 void mono_threads_platform_exit (int exit_code);
486 HANDLE mono_threads_platform_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
487 void mono_threads_platform_close_thread_handle (HANDLE handle);
488 void mono_threads_platform_set_exited (gpointer handle);
489 gpointer mono_threads_platform_duplicate_handle (THREAD_INFO_TYPE *info);
491 void mono_threads_coop_begin_global_suspend (void);
492 void mono_threads_coop_end_global_suspend (void);
494 MONO_API MonoNativeThreadId
495 mono_native_thread_id_get (void);
498 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
501 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
504 mono_native_thread_set_name (MonoNativeThreadId tid, const char *name);
507 mono_native_thread_join (MonoNativeThreadId tid);
509 /*Mach specific internals */
510 void mono_threads_init_dead_letter (void);
511 void mono_threads_install_dead_letter (void);
513 /* mono-threads internal API used by the backends. */
515 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
517 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
519 This tells the resume initiator that we completed resume duties and will return to runnable state.
521 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
524 This tells the resume initiator that we completed abort duties and will return to previous state.
526 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
528 /* Thread state machine functions */
533 ResumeInitSelfResume,
534 ResumeInitAsyncResume,
535 ResumeInitBlockingResume,
541 SelfSuspendNotifyAndWait,
542 } MonoSelfSupendResult;
545 AsyncSuspendAlreadySuspended,
547 AsyncSuspendInitSuspend,
548 AsyncSuspendBlocking,
549 } MonoRequestAsyncSuspendResult;
552 DoBlockingContinue, //in blocking mode, continue
553 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
554 } MonoDoBlockingResult;
557 DoneBlockingOk, //exited blocking fine
558 DoneBlockingWait, //thread should end suspended
559 } MonoDoneBlockingResult;
563 AbortBlockingIgnore, //Ignore
564 AbortBlockingIgnoreAndPoll, //Ignore and poll
565 AbortBlockingOk, //Abort worked
566 AbortBlockingWait, //Abort worked, but should wait for resume
567 } MonoAbortBlockingResult;
570 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
571 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
572 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
573 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
574 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
575 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
576 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
577 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
578 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
579 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
581 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
584 mono_threads_enter_gc_unsafe_region_cookie (void);
587 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
588 /* Advanced suspend API, used for suspending multiple threads as once. */
589 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
590 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
591 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
592 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
593 const char* mono_thread_state_name (int state);
595 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
596 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
597 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
599 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
600 gboolean mono_threads_wait_pending_operations (void);
601 void mono_threads_begin_global_suspend (void);
602 void mono_threads_end_global_suspend (void);
605 mono_thread_info_is_current (THREAD_INFO_TYPE *info);
608 mono_thread_info_duplicate_handle (THREAD_INFO_TYPE *info);
610 #endif /* __MONO_THREADS_H__ */