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 /* MonoHandleArena for coop handles */
241 gpointer handle_arena;
245 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
247 This callback is called with @info still on the thread list.
248 This call is made while holding the suspend lock, so don't do callbacks.
249 SMR remains functional as its small_id has not been reclaimed.
251 void (*thread_unregister)(THREAD_INFO_TYPE *info);
253 This callback is called right before thread_unregister. This is called
254 without any locks held so it's the place for complicated cleanup.
256 The thread must remain operational between this call and thread_unregister.
257 It must be possible to successfully suspend it after thread_unregister completes.
259 void (*thread_detach)(THREAD_INFO_TYPE *info);
260 void (*thread_attach)(THREAD_INFO_TYPE *info);
261 gboolean (*mono_method_is_critical) (void *method);
262 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
263 } MonoThreadInfoCallbacks;
266 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
267 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
268 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
269 void (*thread_state_init) (MonoThreadUnwindState *tctx);
270 } MonoThreadInfoRuntimeCallbacks;
272 //Not using 0 and 1 to ensure callbacks are not returning bad data
274 MonoResumeThread = 0x1234,
275 KeepSuspended = 0x4321,
276 } SuspendThreadResult;
278 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
280 static inline gboolean
281 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
283 return !((MonoThreadInfo*)info)->tools_thread;
287 Requires the world to be stoped
289 #define FOREACH_THREAD(thread) \
290 MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
292 #define FOREACH_THREAD_END \
298 #define FOREACH_THREAD_SAFE(thread) \
299 MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
301 #define FOREACH_THREAD_SAFE_END \
302 MONO_LLS_FOREACH_SAFE_END
304 static inline MonoNativeThreadId
305 mono_thread_info_get_tid (THREAD_INFO_TYPE *info)
307 return MONO_UINT_TO_NATIVE_THREAD_ID (((MonoThreadInfo*) info)->node.key);
311 mono_thread_info_set_tid (THREAD_INFO_TYPE *info, MonoNativeThreadId tid)
313 ((MonoThreadInfo*) info)->node.key = (uintptr_t) MONO_NATIVE_THREAD_ID_TO_UINT (tid);
317 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
318 * a single block with info from both camps.
321 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
324 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
326 MonoThreadInfoRuntimeCallbacks *
327 mono_threads_get_runtime_callbacks (void);
330 mono_thread_info_register_small_id (void);
333 mono_thread_info_attach (void *baseptr);
336 mono_thread_info_detach (void);
339 mono_thread_info_is_exiting (void);
342 mono_thread_info_current (void);
345 mono_thread_info_current_unchecked (void);
348 mono_thread_info_get_small_id (void);
351 mono_thread_info_list_head (void);
354 mono_thread_info_lookup (MonoNativeThreadId id);
357 mono_thread_info_resume (MonoNativeThreadId tid);
360 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
362 //XXX new API, fix the world
364 mono_thread_info_begin_self_suspend (void);
367 mono_thread_info_end_self_suspend (void);
372 mono_thread_info_unified_management_enabled (void);
375 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
378 mono_thread_info_suspend_lock (void);
381 mono_thread_info_suspend_unlock (void);
384 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
387 mono_thread_info_set_is_async_context (gboolean async_context);
390 mono_thread_info_is_async_context (void);
393 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
396 mono_thread_info_yield (void);
399 mono_thread_info_sleep (guint32 ms, gboolean *alerted);
402 mono_thread_info_usleep (guint64 us);
405 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
408 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
411 mono_thread_info_exit (void);
414 mono_thread_info_open_handle (void);
417 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
420 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
422 MonoThreadInfoInterruptToken*
423 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
426 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
429 mono_thread_info_self_interrupt (void);
432 mono_thread_info_clear_self_interrupt (void);
435 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
438 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
441 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
444 mono_threads_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
447 mono_threads_get_max_stack_size (void);
450 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
453 mono_threads_attach_tools_thread (void);
456 #if !defined(HOST_WIN32)
458 /*Use this instead of pthread_kill */
460 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
462 #endif /* !defined(HOST_WIN32) */
464 /* Internal API between mono-threads and its backends. */
466 /* Backend functions - a backend must implement all of the following */
468 This is called very early in the runtime, it cannot access any runtime facilities.
471 void mono_threads_init_platform (void); //ok
473 void mono_threads_init_coop (void);
475 void mono_threads_init_abort_syscall (void);
478 This begins async suspend. This function must do the following:
480 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
481 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
482 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
484 If begin suspend fails the thread must be left uninterrupted and resumed.
486 gboolean mono_threads_core_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
489 This verifies the outcome of an async suspend operation.
491 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
492 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
494 gboolean mono_threads_core_check_suspend_result (THREAD_INFO_TYPE *info);
497 This begins async resume. This function must do the following:
499 - Install an async target if one was requested.
500 - Notify the target to resume.
501 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
503 gboolean mono_threads_core_begin_async_resume (THREAD_INFO_TYPE *info);
505 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
506 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
507 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
508 gboolean mono_threads_core_needs_abort_syscall (void);
509 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
510 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
511 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
512 gboolean mono_threads_core_yield (void);
513 void mono_threads_core_exit (int exit_code);
514 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
515 HANDLE mono_threads_core_open_handle (void);
516 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
518 void mono_threads_coop_begin_global_suspend (void);
519 void mono_threads_coop_end_global_suspend (void);
521 MONO_API MonoNativeThreadId
522 mono_native_thread_id_get (void);
525 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
528 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
531 mono_native_thread_set_name (MonoNativeThreadId tid, const char *name);
533 /*Mach specific internals */
534 void mono_threads_init_dead_letter (void);
535 void mono_threads_install_dead_letter (void);
537 /* mono-threads internal API used by the backends. */
539 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
541 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
543 This tells the resume initiator that we completed resume duties and will return to runnable state.
545 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
548 This tells the resume initiator that we completed abort duties and will return to previous state.
550 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
552 /* Thread state machine functions */
557 ResumeInitSelfResume,
558 ResumeInitAsyncResume,
559 ResumeInitBlockingResume,
565 SelfSuspendNotifyAndWait,
566 } MonoSelfSupendResult;
569 AsyncSuspendAlreadySuspended,
571 AsyncSuspendInitSuspend,
572 AsyncSuspendBlocking,
573 } MonoRequestAsyncSuspendResult;
576 DoBlockingContinue, //in blocking mode, continue
577 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
578 } MonoDoBlockingResult;
581 DoneBlockingOk, //exited blocking fine
582 DoneBlockingWait, //thread should end suspended
583 } MonoDoneBlockingResult;
587 AbortBlockingIgnore, //Ignore
588 AbortBlockingIgnoreAndPoll, //Ignore and poll
589 AbortBlockingOk, //Abort worked
590 AbortBlockingWait, //Abort worked, but should wait for resume
591 } MonoAbortBlockingResult;
594 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
595 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
596 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
597 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
598 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
599 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
600 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
601 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
602 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
603 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
605 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
608 mono_threads_enter_gc_unsafe_region_cookie (void);
611 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
612 /* Advanced suspend API, used for suspending multiple threads as once. */
613 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
614 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
615 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
616 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
617 const char* mono_thread_state_name (int state);
619 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
620 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
621 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
623 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
624 gboolean mono_threads_wait_pending_operations (void);
625 void mono_threads_begin_global_suspend (void);
626 void mono_threads_end_global_suspend (void);
629 mono_thread_info_is_current (THREAD_INFO_TYPE *info);
631 #endif /* __MONO_THREADS_H__ */