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 /* Logging - enable them below if you need specific logging for the category you need */
94 #define MOSTLY_ASYNC_SAFE_PRINTF(...) do { \
95 char __buff[1024]; __buff [0] = '\0'; \
96 g_snprintf (__buff, sizeof (__buff), __VA_ARGS__); \
97 write (1, __buff, strlen (__buff)); \
102 #define THREADS_DEBUG(...)
104 #define THREADS_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
108 #define THREADS_STW_DEBUG(...)
110 #define THREADS_STW_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
114 #define THREADS_SUSPEND_DEBUG(...)
116 #define THREADS_SUSPEND_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
120 #define THREADS_STATE_MACHINE_DEBUG(...)
122 #define THREADS_STATE_MACHINE_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
126 #define THREADS_INTERRUPT_DEBUG(...)
128 #define THREADS_INTERRUPT_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
131 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
132 // #define USE_SIGNALS_ON_MACH
134 #if defined (_POSIX_VERSION) || defined (__native_client__)
135 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
136 #define USE_MACH_BACKEND
138 #define USE_POSIX_BACKEND
141 #define USE_WINDOWS_BACKEND
143 #error "no backend support for current platform"
144 #endif /* defined (_POSIX_VERSION) || defined (__native_client__) */
147 STATE_STARTING = 0x00,
148 STATE_RUNNING = 0x01,
149 STATE_DETACHED = 0x02,
151 STATE_ASYNC_SUSPENDED = 0x03,
152 STATE_SELF_SUSPENDED = 0x04,
153 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
154 STATE_SELF_SUSPEND_REQUESTED = 0x06,
155 STATE_BLOCKING = 0x07,
156 STATE_BLOCKING_AND_SUSPENDED = 0x8,
160 THREAD_STATE_MASK = 0x00FF,
161 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
162 THREAD_SUSPEND_COUNT_SHIFT = 8,
163 THREAD_SUSPEND_COUNT_MAX = 0xFF,
165 SELF_SUSPEND_STATE_INDEX = 0,
166 ASYNC_SUSPEND_STATE_INDEX = 1,
169 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
172 MonoLinkedListSetNode node;
173 guint32 small_id; /*Used by hazard pointers */
174 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
177 /*Tells if this thread was created by the runtime or not.*/
178 gboolean runtime_thread;
180 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
181 gboolean tools_thread;
183 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
184 void *stack_start_limit, *stack_end;
186 /* suspend machinery, fields protected by suspend_semaphore */
187 MonoSemType suspend_semaphore;
190 MonoSemType resume_semaphore;
192 /* only needed by the posix backend */
193 #if defined(USE_POSIX_BACKEND)
194 MonoSemType finish_resume_semaphore;
195 gboolean syscall_break_signal;
199 gboolean suspend_can_continue;
201 /* This memory pool is used by coop GC to save stack data roots between GC unsafe regions */
202 GByteArray *stackdata;
204 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
205 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
207 /*async call machinery, thread MUST be suspended before accessing those fields*/
208 void (*async_target)(void*);
212 If true, this thread is running a critical region of code and cannot be suspended.
213 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
214 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
216 gboolean inside_critical_region;
219 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
220 * operations like locking without having to pass an 'async' parameter around.
222 gboolean is_async_context;
225 * Values of TLS variables for this thread.
226 * This can be used to obtain the values of TLS variable for threads
227 * other than the current one.
229 gpointer tls [TLS_KEY_NUM];
231 /* IO layer handle for this thread */
232 /* Set when the thread is started, or in _wapi_thread_duplicate () */
237 MonoThreadInfoInterruptToken *interrupt_token;
239 /* HandleStack for coop handles */
240 gpointer handle_stack;
242 /* Stack mark for targets that explicitly require one */
245 #if defined(_POSIX_VERSION) || defined(__native_client__)
246 /* This is the data that was stored in the w32 handle */
247 GPtrArray *owned_mutexes;
252 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
254 This callback is called with @info still on the thread list.
255 This call is made while holding the suspend lock, so don't do callbacks.
256 SMR remains functional as its small_id has not been reclaimed.
258 void (*thread_unregister)(THREAD_INFO_TYPE *info);
260 This callback is called right before thread_unregister. This is called
261 without any locks held so it's the place for complicated cleanup.
263 The thread must remain operational between this call and thread_unregister.
264 It must be possible to successfully suspend it after thread_unregister completes.
266 void (*thread_detach)(THREAD_INFO_TYPE *info);
267 void (*thread_attach)(THREAD_INFO_TYPE *info);
268 gboolean (*mono_method_is_critical) (void *method);
269 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
270 } MonoThreadInfoCallbacks;
273 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
274 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
275 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
276 void (*thread_state_init) (MonoThreadUnwindState *tctx);
277 } MonoThreadInfoRuntimeCallbacks;
279 //Not using 0 and 1 to ensure callbacks are not returning bad data
281 MonoResumeThread = 0x1234,
282 KeepSuspended = 0x4321,
283 } SuspendThreadResult;
285 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
287 static inline gboolean
288 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
290 return !((MonoThreadInfo*)info)->tools_thread;
294 Requires the world to be stoped
296 #define FOREACH_THREAD(thread) \
297 MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
299 #define FOREACH_THREAD_END \
305 #define FOREACH_THREAD_SAFE(thread) \
306 MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
308 #define FOREACH_THREAD_SAFE_END \
309 MONO_LLS_FOREACH_SAFE_END
311 static inline MonoNativeThreadId
312 mono_thread_info_get_tid (THREAD_INFO_TYPE *info)
314 return MONO_UINT_TO_NATIVE_THREAD_ID (((MonoThreadInfo*) info)->node.key);
318 mono_thread_info_set_tid (THREAD_INFO_TYPE *info, MonoNativeThreadId tid)
320 ((MonoThreadInfo*) info)->node.key = (uintptr_t) MONO_NATIVE_THREAD_ID_TO_UINT (tid);
324 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
325 * a single block with info from both camps.
328 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
331 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
333 MonoThreadInfoRuntimeCallbacks *
334 mono_threads_get_runtime_callbacks (void);
337 mono_thread_info_register_small_id (void);
340 mono_thread_info_attach (void *baseptr);
343 mono_thread_info_detach (void);
346 mono_thread_info_is_exiting (void);
349 mono_thread_info_current (void);
352 mono_thread_info_current_unchecked (void);
355 mono_thread_info_get_small_id (void);
358 mono_thread_info_list_head (void);
361 mono_thread_info_lookup (MonoNativeThreadId id);
364 mono_thread_info_resume (MonoNativeThreadId tid);
367 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
369 //XXX new API, fix the world
371 mono_thread_info_begin_self_suspend (void);
374 mono_thread_info_end_self_suspend (void);
379 mono_thread_info_unified_management_enabled (void);
382 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
385 mono_thread_info_suspend_lock (void);
388 mono_thread_info_suspend_unlock (void);
391 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
394 mono_thread_info_set_is_async_context (gboolean async_context);
397 mono_thread_info_is_async_context (void);
400 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
403 mono_thread_info_yield (void);
406 mono_thread_info_sleep (guint32 ms, gboolean *alerted);
409 mono_thread_info_usleep (guint64 us);
412 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
415 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
418 mono_thread_info_exit (void);
421 mono_thread_info_set_exited (THREAD_INFO_TYPE *info);
424 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
427 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
429 MonoThreadInfoInterruptToken*
430 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
433 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
436 mono_thread_info_self_interrupt (void);
439 mono_thread_info_clear_self_interrupt (void);
442 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
445 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
448 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
451 mono_threads_create_thread (MonoThreadStart start, gpointer arg, gsize stack_size, MonoNativeThreadId *out_tid);
454 mono_threads_get_max_stack_size (void);
457 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
460 mono_threads_close_thread_handle (HANDLE handle);
463 mono_threads_attach_tools_thread (void);
466 #if !defined(HOST_WIN32)
468 /*Use this instead of pthread_kill */
470 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
472 #endif /* !defined(HOST_WIN32) */
474 /* Internal API between mono-threads and its backends. */
476 /* Backend functions - a backend must implement all of the following */
478 This is called very early in the runtime, it cannot access any runtime facilities.
481 void mono_threads_suspend_init (void); //ok
483 void mono_threads_platform_init (void);
485 void mono_threads_coop_init (void);
487 void mono_threads_abort_syscall_init (void);
490 This begins async suspend. This function must do the following:
492 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
493 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
494 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
496 If begin suspend fails the thread must be left uninterrupted and resumed.
498 gboolean mono_threads_suspend_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
501 This verifies the outcome of an async suspend operation.
503 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
504 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
506 gboolean mono_threads_suspend_check_suspend_result (THREAD_INFO_TYPE *info);
509 This begins async resume. This function must do the following:
511 - Install an async target if one was requested.
512 - Notify the target to resume.
513 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
515 gboolean mono_threads_suspend_begin_async_resume (THREAD_INFO_TYPE *info);
517 void mono_threads_suspend_register (THREAD_INFO_TYPE *info); //ok
518 void mono_threads_suspend_free (THREAD_INFO_TYPE *info);
519 void mono_threads_suspend_abort_syscall (THREAD_INFO_TYPE *info);
520 gboolean mono_threads_suspend_needs_abort_syscall (void);
522 void mono_threads_platform_register (THREAD_INFO_TYPE *info);
523 void mono_threads_platform_unregister (THREAD_INFO_TYPE *info);
524 int mono_threads_platform_create_thread (MonoThreadStart thread_fn, gpointer thread_data, gsize stack_size, MonoNativeThreadId *out_tid);
525 void mono_threads_platform_get_stack_bounds (guint8 **staddr, size_t *stsize);
526 gboolean mono_threads_platform_yield (void);
527 void mono_threads_platform_exit (int exit_code);
528 HANDLE mono_threads_platform_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
529 void mono_threads_platform_close_thread_handle (HANDLE handle);
530 void mono_threads_platform_set_exited (THREAD_INFO_TYPE *info);
531 void mono_threads_platform_describe (THREAD_INFO_TYPE *info, GString *text);
532 void mono_threads_platform_own_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
533 void mono_threads_platform_disown_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
534 gpointer mono_threads_platform_duplicate_handle (THREAD_INFO_TYPE *info);
536 void mono_threads_coop_begin_global_suspend (void);
537 void mono_threads_coop_end_global_suspend (void);
539 MONO_API MonoNativeThreadId
540 mono_native_thread_id_get (void);
543 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
546 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
549 mono_native_thread_set_name (MonoNativeThreadId tid, const char *name);
551 /*Mach specific internals */
552 void mono_threads_init_dead_letter (void);
553 void mono_threads_install_dead_letter (void);
555 /* mono-threads internal API used by the backends. */
557 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
559 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
561 This tells the resume initiator that we completed resume duties and will return to runnable state.
563 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
566 This tells the resume initiator that we completed abort duties and will return to previous state.
568 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
570 /* Thread state machine functions */
575 ResumeInitSelfResume,
576 ResumeInitAsyncResume,
577 ResumeInitBlockingResume,
583 SelfSuspendNotifyAndWait,
584 } MonoSelfSupendResult;
587 AsyncSuspendAlreadySuspended,
589 AsyncSuspendInitSuspend,
590 AsyncSuspendBlocking,
591 } MonoRequestAsyncSuspendResult;
594 DoBlockingContinue, //in blocking mode, continue
595 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
596 } MonoDoBlockingResult;
599 DoneBlockingOk, //exited blocking fine
600 DoneBlockingWait, //thread should end suspended
601 } MonoDoneBlockingResult;
605 AbortBlockingIgnore, //Ignore
606 AbortBlockingIgnoreAndPoll, //Ignore and poll
607 AbortBlockingOk, //Abort worked
608 AbortBlockingWait, //Abort worked, but should wait for resume
609 } MonoAbortBlockingResult;
612 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
613 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
614 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
615 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
616 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
617 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
618 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
619 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
620 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
621 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
623 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
626 mono_threads_enter_gc_unsafe_region_cookie (void);
629 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
630 /* Advanced suspend API, used for suspending multiple threads as once. */
631 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
632 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
633 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
634 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
635 const char* mono_thread_state_name (int state);
637 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
638 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
639 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
641 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
642 gboolean mono_threads_wait_pending_operations (void);
643 void mono_threads_begin_global_suspend (void);
644 void mono_threads_end_global_suspend (void);
647 mono_thread_info_is_current (THREAD_INFO_TYPE *info);
650 mono_thread_info_duplicate_handle (THREAD_INFO_TYPE *info);
653 mono_thread_info_describe (THREAD_INFO_TYPE *info, GString *text);
656 mono_thread_info_own_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
659 mono_thread_info_disown_mutex (THREAD_INFO_TYPE *info, gpointer mutex_handle);
661 #endif /* __MONO_THREADS_H__ */