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-threads-coop.h>
18 #include <mono/utils/mono-threads-api.h>
19 #include <mono/utils/mono-coop-semaphore.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;
34 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (tid)
35 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) ((MonoNativeThreadId)(tid))
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 #endif /* #ifdef HOST_WIN32 */
64 THREAD_INFO_TYPE is a way to make the mono-threads module parametric - or sort of.
65 The GC using mono-threads might extend the MonoThreadInfo struct to add its own
66 data, this avoid a pointer indirection on what is on a lot of hot paths.
68 But extending MonoThreadInfo has de disavantage that all functions here return type
69 would require a cast, something like the following:
77 ((MyThreadInfo*)mono_thread_info_current ())->stuff = 1;
79 While porting sgen to use mono-threads, the number of casts required was too much and
80 code ended up looking horrible. So we use this cute little hack. The idea is that
81 whomever is including this header can set the expected type to be used by functions here
82 and reduce the number of casts drastically.
85 #ifndef THREAD_INFO_TYPE
86 #define THREAD_INFO_TYPE MonoThreadInfo
89 /* Mono Threads internal configuration knows*/
91 /* Logging - enable them below if you need specific logging for the category you need */
92 #define MOSTLY_ASYNC_SAFE_PRINTF(...) do { \
93 char __buff[1024]; __buff [0] = '\0'; \
94 g_snprintf (__buff, sizeof (__buff), __VA_ARGS__); \
95 write (1, __buff, strlen (__buff)); \
100 #define THREADS_DEBUG(...)
102 #define THREADS_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
106 #define THREADS_STW_DEBUG(...)
108 #define THREADS_STW_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
112 #define THREADS_SUSPEND_DEBUG(...)
114 #define THREADS_SUSPEND_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
118 #define THREADS_STATE_MACHINE_DEBUG(...)
120 #define THREADS_STATE_MACHINE_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
124 #define THREADS_INTERRUPT_DEBUG(...)
126 #define THREADS_INTERRUPT_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
129 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
130 // #define USE_SIGNALS_ON_MACH
132 #if defined (_POSIX_VERSION) || defined (__native_client__)
133 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
134 #define USE_MACH_BACKEND
136 #define USE_POSIX_BACKEND
139 #define USE_WINDOWS_BACKEND
141 #error "no backend support for current platform"
142 #endif /* defined (_POSIX_VERSION) || defined (__native_client__) */
145 STATE_STARTING = 0x00,
146 STATE_RUNNING = 0x01,
147 STATE_DETACHED = 0x02,
149 STATE_ASYNC_SUSPENDED = 0x03,
150 STATE_SELF_SUSPENDED = 0x04,
151 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
152 STATE_SELF_SUSPEND_REQUESTED = 0x06,
153 STATE_BLOCKING = 0x07,
154 STATE_BLOCKING_AND_SUSPENDED = 0x8,
158 THREAD_STATE_MASK = 0x00FF,
159 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
160 THREAD_SUSPEND_COUNT_SHIFT = 8,
161 THREAD_SUSPEND_COUNT_MAX = 0xFF,
163 SELF_SUSPEND_STATE_INDEX = 0,
164 ASYNC_SUSPEND_STATE_INDEX = 1,
167 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
170 MonoLinkedListSetNode node;
171 guint32 small_id; /*Used by hazard pointers */
172 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
175 /*Tells if this thread was created by the runtime or not.*/
176 gboolean runtime_thread;
178 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
179 gboolean tools_thread;
181 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
182 void *stack_start_limit, *stack_end;
184 /* suspend machinery, fields protected by suspend_semaphore */
185 MonoSemType suspend_semaphore;
188 MonoSemType resume_semaphore;
190 /* only needed by the posix backend */
191 #if defined(USE_POSIX_BACKEND)
192 MonoSemType finish_resume_semaphore;
193 gboolean syscall_break_signal;
194 gboolean suspend_can_continue;
198 /* This memory pool is used by coop GC to save stack data roots between GC unsafe regions */
199 GByteArray *stackdata;
201 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
202 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
204 /*async call machinery, thread MUST be suspended before accessing those fields*/
205 void (*async_target)(void*);
209 If true, this thread is running a critical region of code and cannot be suspended.
210 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
211 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
213 gboolean inside_critical_region;
216 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
217 * operations like locking without having to pass an 'async' parameter around.
219 gboolean is_async_context;
221 gboolean create_suspended;
223 /* Semaphore used to implement CREATE_SUSPENDED */
224 MonoCoopSem create_suspended_sem;
227 * Values of TLS variables for this thread.
228 * This can be used to obtain the values of TLS variable for threads
229 * other than the current one.
231 gpointer tls [TLS_KEY_NUM];
233 /* IO layer handle for this thread */
234 /* Set when the thread is started, or in _wapi_thread_duplicate () */
239 MonoThreadInfoInterruptToken *interrupt_token;
241 /* MonoHandleArena for coop handles */
242 gpointer handle_arena;
246 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
248 This callback is called with @info still on the thread list.
249 This call is made while holding the suspend lock, so don't do callbacks.
250 SMR remains functional as its small_id has not been reclaimed.
252 void (*thread_unregister)(THREAD_INFO_TYPE *info);
254 This callback is called right before thread_unregister. This is called
255 without any locks held so it's the place for complicated cleanup.
257 The thread must remain operational between this call and thread_unregister.
258 It must be possible to successfully suspend it after thread_unregister completes.
260 void (*thread_detach)(THREAD_INFO_TYPE *info);
261 void (*thread_attach)(THREAD_INFO_TYPE *info);
262 gboolean (*mono_method_is_critical) (void *method);
263 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
264 } MonoThreadInfoCallbacks;
267 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
268 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
269 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
270 void (*thread_state_init) (MonoThreadUnwindState *tctx);
271 } MonoThreadInfoRuntimeCallbacks;
273 //Not using 0 and 1 to ensure callbacks are not returning bad data
275 MonoResumeThread = 0x1234,
276 KeepSuspended = 0x4321,
277 } SuspendThreadResult;
279 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
281 static inline gboolean
282 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
284 return !((MonoThreadInfo*)info)->tools_thread;
288 Requires the world to be stoped
290 #define FOREACH_THREAD(thread) \
291 MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
293 #define FOREACH_THREAD_END \
299 #define FOREACH_THREAD_SAFE(thread) \
300 MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
302 #define FOREACH_THREAD_SAFE_END \
303 MONO_LLS_FOREACH_SAFE_END
305 static inline MonoNativeThreadId
306 mono_thread_info_get_tid (THREAD_INFO_TYPE *info)
308 return MONO_UINT_TO_NATIVE_THREAD_ID (((MonoThreadInfo*) info)->node.key);
312 mono_thread_info_set_tid (THREAD_INFO_TYPE *info, MonoNativeThreadId tid)
314 ((MonoThreadInfo*) info)->node.key = (uintptr_t) MONO_NATIVE_THREAD_ID_TO_UINT (tid);
318 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
319 * a single block with info from both camps.
322 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
325 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
327 MonoThreadInfoRuntimeCallbacks *
328 mono_threads_get_runtime_callbacks (void);
331 mono_thread_info_register_small_id (void);
334 mono_thread_info_attach (void *baseptr);
337 mono_thread_info_detach (void);
340 mono_thread_info_is_exiting (void);
343 mono_thread_info_current (void);
346 mono_thread_info_current_unchecked (void);
349 mono_thread_info_get_small_id (void);
352 mono_thread_info_list_head (void);
355 mono_thread_info_lookup (MonoNativeThreadId id);
358 mono_thread_info_resume (MonoNativeThreadId tid);
361 mono_thread_info_set_name (MonoNativeThreadId tid, const char *name);
364 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
366 //XXX new API, fix the world
368 mono_thread_info_begin_self_suspend (void);
371 mono_thread_info_end_self_suspend (void);
376 mono_thread_info_unified_management_enabled (void);
379 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
382 mono_thread_info_suspend_lock (void);
385 mono_thread_info_suspend_unlock (void);
388 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
391 mono_thread_info_set_is_async_context (gboolean async_context);
394 mono_thread_info_is_async_context (void);
397 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
400 mono_thread_info_yield (void);
403 mono_thread_info_sleep (guint32 ms, gboolean *alerted);
406 mono_thread_info_usleep (guint64 us);
409 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
412 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
415 mono_thread_info_exit (void);
418 mono_thread_info_open_handle (void);
421 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
424 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
426 MonoThreadInfoInterruptToken*
427 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
430 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
433 mono_thread_info_self_interrupt (void);
436 mono_thread_info_clear_self_interrupt (void);
439 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
442 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
445 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
448 mono_threads_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
451 mono_threads_get_max_stack_size (void);
454 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
457 mono_threads_attach_tools_thread (void);
460 #if !defined(HOST_WIN32)
462 /*Use this instead of pthread_kill */
464 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
466 #endif /* !defined(HOST_WIN32) */
468 /* Internal API between mono-threads and its backends. */
470 /* Backend functions - a backend must implement all of the following */
472 This is called very early in the runtime, it cannot access any runtime facilities.
475 void mono_threads_init_platform (void); //ok
477 void mono_threads_init_coop (void);
479 void mono_threads_init_abort_syscall (void);
482 This begins async suspend. This function must do the following:
484 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
485 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
486 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
488 If begin suspend fails the thread must be left uninterrupted and resumed.
490 gboolean mono_threads_core_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
493 This verifies the outcome of an async suspend operation.
495 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
496 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
498 gboolean mono_threads_core_check_suspend_result (THREAD_INFO_TYPE *info);
501 This begins async resume. This function must do the following:
503 - Install an async target if one was requested.
504 - Notify the target to resume.
505 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
507 gboolean mono_threads_core_begin_async_resume (THREAD_INFO_TYPE *info);
509 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
510 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
511 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
512 gboolean mono_threads_core_needs_abort_syscall (void);
513 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
514 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
515 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
516 gboolean mono_threads_core_yield (void);
517 void mono_threads_core_exit (int exit_code);
518 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
519 HANDLE mono_threads_core_open_handle (void);
520 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
521 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
523 void mono_threads_coop_begin_global_suspend (void);
524 void mono_threads_coop_end_global_suspend (void);
527 mono_native_thread_id_get (void);
530 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
533 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
535 /*Mach specific internals */
536 void mono_threads_init_dead_letter (void);
537 void mono_threads_install_dead_letter (void);
539 /* mono-threads internal API used by the backends. */
541 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
543 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
545 This tells the resume initiator that we completed resume duties and will return to runnable state.
547 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
550 This tells the resume initiator that we completed abort duties and will return to previous state.
552 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
554 /* Thread state machine functions */
559 ResumeInitSelfResume,
560 ResumeInitAsyncResume,
561 ResumeInitBlockingResume,
567 SelfSuspendNotifyAndWait,
568 } MonoSelfSupendResult;
571 AsyncSuspendAlreadySuspended,
573 AsyncSuspendInitSuspend,
574 AsyncSuspendBlocking,
575 } MonoRequestAsyncSuspendResult;
578 DoBlockingContinue, //in blocking mode, continue
579 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
580 } MonoDoBlockingResult;
583 DoneBlockingAborted, //blocking was aborted and not properly restored, poll the state
584 DoneBlockingOk, //exited blocking fine
585 DoneBlockingWait, //thread should end suspended
586 } MonoDoneBlockingResult;
590 AbortBlockingIgnore, //Ignore
591 AbortBlockingIgnoreAndPoll, //Ignore and pool
592 AbortBlockingOk, //Abort worked
593 AbortBlockingOkAndPool, //Abort worked, but pool before
594 } MonoAbortBlockingResult;
597 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
598 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
599 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
600 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
601 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
602 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
603 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
604 void mono_threads_transition_async_suspend_compensation (THREAD_INFO_TYPE* info);
605 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
606 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
607 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
609 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
612 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
613 /* Advanced suspend API, used for suspending multiple threads as once. */
614 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
615 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
616 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
617 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
618 const char* mono_thread_state_name (int state);
620 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
621 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
622 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
625 mono_thread_info_check_suspend_result (THREAD_INFO_TYPE *info);
627 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
628 gboolean mono_threads_wait_pending_operations (void);
629 void mono_threads_begin_global_suspend (void);
630 void mono_threads_end_global_suspend (void);
632 #endif /* __MONO_THREADS_H__ */