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-semaphore.h>
14 #include <mono/utils/mono-stack-unwinding.h>
15 #include <mono/utils/mono-linked-list-set.h>
16 #include <mono/utils/mono-mutex.h>
17 #include <mono/utils/mono-tls.h>
18 #include <mono/utils/mono-threads-coop.h>
26 typedef DWORD MonoNativeThreadId;
27 typedef HANDLE MonoNativeThreadHandle; /* unused */
29 typedef DWORD mono_native_thread_return_t;
31 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (tid)
32 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) ((MonoNativeThreadId)(tid))
39 #include <mono/utils/mach-support.h>
41 typedef thread_port_t MonoNativeThreadHandle;
47 typedef pid_t MonoNativeThreadHandle;
49 #endif /* defined(__MACH__) */
51 typedef pthread_t MonoNativeThreadId;
53 typedef void* mono_native_thread_return_t;
55 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (gsize)(tid)
56 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) (MonoNativeThreadId)(gsize)(tid)
58 #endif /* #ifdef HOST_WIN32 */
61 THREAD_INFO_TYPE is a way to make the mono-threads module parametric - or sort of.
62 The GC using mono-threads might extend the MonoThreadInfo struct to add its own
63 data, this avoid a pointer indirection on what is on a lot of hot paths.
65 But extending MonoThreadInfo has de disavantage that all functions here return type
66 would require a cast, something like the following:
74 ((MyThreadInfo*)mono_thread_info_current ())->stuff = 1;
76 While porting sgen to use mono-threads, the number of casts required was too much and
77 code ended up looking horrible. So we use this cute little hack. The idea is that
78 whomever is including this header can set the expected type to be used by functions here
79 and reduce the number of casts drastically.
82 #ifndef THREAD_INFO_TYPE
83 #define THREAD_INFO_TYPE MonoThreadInfo
86 /* Mono Threads internal configuration knows*/
88 /* Logging - enable them below if you need specific logging for the category you need */
89 #define MOSTLY_ASYNC_SAFE_PRINTF(...) do { \
90 char __buff[1024]; __buff [0] = '\0'; \
91 g_snprintf (__buff, sizeof (__buff), __VA_ARGS__); \
92 write (1, __buff, strlen (__buff)); \
97 #define THREADS_DEBUG(...)
99 #define THREADS_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
103 #define THREADS_STW_DEBUG(...)
105 #define THREADS_STW_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
109 #define THREADS_SUSPEND_DEBUG(...)
111 #define THREADS_SUSPEND_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
115 #define THREADS_STATE_MACHINE_DEBUG(...)
117 #define THREADS_STATE_MACHINE_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
121 #define THREADS_INTERRUPT_DEBUG(...)
123 #define THREADS_INTERRUPT_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
126 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
127 // #define USE_SIGNALS_ON_MACH
130 #if defined (USE_COOP_GC)
131 #define USE_COOP_BACKEND
132 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 1
134 #elif defined (_POSIX_VERSION) || defined (__native_client__)
135 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 0
137 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
138 #define USE_MACH_BACKEND
140 #define USE_POSIX_BACKEND
144 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 0
145 #define USE_WINDOWS_BACKEND
150 STATE_STARTING = 0x00,
151 STATE_RUNNING = 0x01,
152 STATE_DETACHED = 0x02,
154 STATE_ASYNC_SUSPENDED = 0x03,
155 STATE_SELF_SUSPENDED = 0x04,
156 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
157 STATE_SELF_SUSPEND_REQUESTED = 0x06,
158 STATE_BLOCKING = 0x07,
159 STATE_BLOCKING_AND_SUSPENDED = 0x8,
163 THREAD_STATE_MASK = 0x00FF,
164 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
165 THREAD_SUSPEND_COUNT_SHIFT = 8,
166 THREAD_SUSPEND_COUNT_MAX = 0xFF,
168 SELF_SUSPEND_STATE_INDEX = 0,
169 ASYNC_SUSPEND_STATE_INDEX = 1,
173 * This enum tells which async thread service corresponds to which bit.
176 MONO_SERVICE_REQUEST_SAMPLE = 1,
179 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
182 MonoLinkedListSetNode node;
183 guint32 small_id; /*Used by hazard pointers */
184 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
187 /*Tells if this thread was created by the runtime or not.*/
188 gboolean runtime_thread;
190 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
191 gboolean tools_thread;
193 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
194 void *stack_start_limit, *stack_end;
196 /* suspend machinery, fields protected by suspend_semaphore */
197 MonoSemType suspend_semaphore;
200 MonoSemType resume_semaphore;
202 /* only needed by the posix backend */
203 #if defined(USE_POSIX_BACKEND)
204 MonoSemType finish_resume_semaphore;
205 gboolean syscall_break_signal;
206 gboolean suspend_can_continue;
211 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
212 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
214 /*async call machinery, thread MUST be suspended before accessing those fields*/
215 void (*async_target)(void*);
219 If true, this thread is running a critical region of code and cannot be suspended.
220 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
221 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
223 gboolean inside_critical_region;
226 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
227 * operations like locking without having to pass an 'async' parameter around.
229 gboolean is_async_context;
231 gboolean create_suspended;
233 /* Semaphore used to implement CREATE_SUSPENDED */
234 MonoSemType create_suspended_sem;
237 * Values of TLS variables for this thread.
238 * This can be used to obtain the values of TLS variable for threads
239 * other than the current one.
241 gpointer tls [TLS_KEY_NUM];
243 /* IO layer handle for this thread */
244 /* Set when the thread is started, or in _wapi_thread_duplicate () */
247 /* Asynchronous service request. This flag is meant to be consumed by the multiplexing signal handlers to discover what sort of work they need to do.
248 * Use the mono_threads_add_async_job and mono_threads_consume_async_jobs APIs to modify this flag.
249 * In the future the signaling should be part of the API, but for now, it's only for massaging the bits.
251 volatile gint32 service_requests;
255 MonoThreadInfoInterruptToken *interrupt_token;
259 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
261 This callback is called with @info still on the thread list.
262 This call is made while holding the suspend lock, so don't do callbacks.
263 SMR remains functional as its small_id has not been reclaimed.
265 void (*thread_unregister)(THREAD_INFO_TYPE *info);
267 This callback is called right before thread_unregister. This is called
268 without any locks held so it's the place for complicated cleanup.
270 The thread must remain operational between this call and thread_unregister.
271 It must be possible to successfully suspend it after thread_unregister completes.
273 void (*thread_detach)(THREAD_INFO_TYPE *info);
274 void (*thread_attach)(THREAD_INFO_TYPE *info);
275 gboolean (*mono_method_is_critical) (void *method);
276 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
277 } MonoThreadInfoCallbacks;
280 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
281 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
282 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
283 } MonoThreadInfoRuntimeCallbacks;
285 //Not using 0 and 1 to ensure callbacks are not returning bad data
287 MonoResumeThread = 0x1234,
288 KeepSuspended = 0x4321,
289 } SuspendThreadResult;
291 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
293 static inline gboolean
294 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
296 return !((MonoThreadInfo*)info)->tools_thread;
300 Requires the world to be stoped
302 #define FOREACH_THREAD(thread) MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), thread, mono_threads_filter_tools_threads, THREAD_INFO_TYPE*)
303 #define END_FOREACH_THREAD MONO_LLS_END_FOREACH
308 #define FOREACH_THREAD_SAFE(thread) MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), thread, mono_threads_filter_tools_threads, THREAD_INFO_TYPE*)
309 #define END_FOREACH_THREAD_SAFE MONO_LLS_END_FOREACH_SAFE
311 #define mono_thread_info_get_tid(info) ((MonoNativeThreadId)((MonoThreadInfo*)info)->node.key)
312 #define mono_thread_info_set_tid(info, val) do { ((MonoThreadInfo*)(info))->node.key = (uintptr_t)(val); } while (0)
315 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
316 * a single block with info from both camps.
319 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
322 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
324 MonoThreadInfoRuntimeCallbacks *
325 mono_threads_get_runtime_callbacks (void);
328 mono_thread_info_register_small_id (void);
331 mono_thread_info_attach (void *baseptr);
334 mono_thread_info_detach (void);
337 mono_thread_info_is_exiting (void);
340 mono_thread_info_current (void);
343 mono_thread_info_current_unchecked (void);
346 mono_thread_info_get_small_id (void);
349 mono_thread_info_list_head (void);
352 mono_thread_info_lookup (MonoNativeThreadId id);
355 mono_thread_info_safe_suspend_sync (MonoNativeThreadId tid, gboolean interrupt_kernel);
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_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
406 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
409 mono_thread_info_exit (void);
412 mono_thread_info_open_handle (void);
415 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
418 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
420 MonoThreadInfoInterruptToken*
421 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
424 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
427 mono_thread_info_self_interrupt (void);
430 mono_thread_info_clear_self_interrupt (void);
433 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
436 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
439 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
442 mono_threads_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
445 mono_threads_get_max_stack_size (void);
448 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
451 This is the async job submission/consumption API.
452 XXX: This is a PROVISIONAL API only meant to be used by the statistical profiler.
453 If you want to use/extend it anywhere else, understand that you'll have to do some API design work to better fit this puppy.
456 mono_threads_add_async_job (THREAD_INFO_TYPE *info, MonoAsyncJob job);
459 mono_threads_consume_async_jobs (void);
462 mono_threads_attach_tools_thread (void);
465 #if !defined(HOST_WIN32)
467 /*Use this instead of pthread_kill */
469 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
471 #endif /* !defined(HOST_WIN32) */
473 /* Plartform specific functions DON'T use them */
474 void mono_threads_init_platform (void); //ok
475 gboolean mono_threads_core_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
476 gboolean mono_threads_core_resume (THREAD_INFO_TYPE *info);
477 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
478 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
479 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
480 gboolean mono_threads_core_needs_abort_syscall (void);
481 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
482 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
483 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
484 gboolean mono_threads_core_yield (void);
485 void mono_threads_core_exit (int exit_code);
486 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
487 HANDLE mono_threads_core_open_handle (void);
488 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
489 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
491 void mono_threads_core_begin_global_suspend (void);
492 void mono_threads_core_end_global_suspend (void);
494 /* Internal API between mono-threads and its backends. */
496 /* Backend functions - a backend must implement all of the following */
498 This is called very early in the runtime, it cannot access any runtime facilities.
501 void mono_threads_init_platform (void); //ok
504 This begins async suspend. This function must do the following:
506 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
507 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
508 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
510 If begin suspend fails the thread must be left uninterrupted and resumed.
512 gboolean mono_threads_core_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
515 This verifies the outcome of an async suspend operation.
517 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
518 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
520 gboolean mono_threads_core_check_suspend_result (THREAD_INFO_TYPE *info);
523 This begins async resume. This function must do the following:
525 - Install an async target if one was requested.
526 - Notify the target to resume.
527 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
529 gboolean mono_threads_core_begin_async_resume (THREAD_INFO_TYPE *info);
531 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
532 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
533 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
534 gboolean mono_threads_core_needs_abort_syscall (void);
535 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
536 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
537 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
538 gboolean mono_threads_core_yield (void);
539 void mono_threads_core_exit (int exit_code);
540 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
541 HANDLE mono_threads_core_open_handle (void);
542 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
543 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
545 MonoNativeThreadId mono_native_thread_id_get (void);
547 gboolean mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
550 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
552 /*Mach specific internals */
553 void mono_threads_init_dead_letter (void);
554 void mono_threads_install_dead_letter (void);
556 /* mono-threads internal API used by the backends. */
558 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
560 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
562 This tells the resume initiator that we completed resume duties and will return to runnable state.
564 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
567 This tells the resume initiator that we completed abort duties and will return to previous state.
569 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
571 /* Thread state machine functions */
576 ResumeInitSelfResume,
577 ResumeInitAsyncResume,
578 ResumeInitBlockingResume,
584 SelfSuspendNotifyAndWait,
585 } MonoSelfSupendResult;
588 AsyncSuspendAlreadySuspended,
590 AsyncSuspendInitSuspend,
591 } MonoRequestAsyncSuspendResult;
594 DoBlockingContinue, //in blocking mode, continue
595 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
596 } MonoDoBlockingResult;
599 DoneBlockingAborted, //blocking was aborted and not properly restored, poll the state
600 DoneBlockingOk, //exited blocking fine
601 DoneBlockingWait, //thread should end suspended
602 } MonoDoneBlockingResult;
606 AbortBlockingIgnore, //Ignore
607 AbortBlockingIgnoreAndPoll, //Ignore and pool
608 AbortBlockingOk, //Abort worked
609 AbortBlockingOkAndPool, //Abort worked, but pool before
610 } MonoAbortBlockingResult;
613 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
614 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
615 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
616 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
617 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
618 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
619 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
620 void mono_threads_transition_async_suspend_compensation (THREAD_INFO_TYPE* info);
621 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
622 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
623 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
625 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
628 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
629 /* Advanced suspend API, used for suspending multiple threads as once. */
630 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
631 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
632 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
633 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
635 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
636 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
637 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
640 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
641 gboolean mono_threads_wait_pending_operations (void);
642 void mono_threads_begin_global_suspend (void);
643 void mono_threads_end_global_suspend (void);
645 #endif /* __MONO_THREADS_H__ */