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 */
247 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
249 This callback is called with @info still on the thread list.
250 This call is made while holding the suspend lock, so don't do callbacks.
251 SMR remains functional as its small_id has not been reclaimed.
253 void (*thread_unregister)(THREAD_INFO_TYPE *info);
255 This callback is called right before thread_unregister. This is called
256 without any locks held so it's the place for complicated cleanup.
258 The thread must remain operational between this call and thread_unregister.
259 It must be possible to successfully suspend it after thread_unregister completes.
261 void (*thread_detach)(THREAD_INFO_TYPE *info);
262 void (*thread_attach)(THREAD_INFO_TYPE *info);
263 gboolean (*mono_method_is_critical) (void *method);
264 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
265 } MonoThreadInfoCallbacks;
268 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
269 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
270 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
271 void (*thread_state_init) (MonoThreadUnwindState *tctx);
272 } MonoThreadInfoRuntimeCallbacks;
274 //Not using 0 and 1 to ensure callbacks are not returning bad data
276 MonoResumeThread = 0x1234,
277 KeepSuspended = 0x4321,
278 } SuspendThreadResult;
280 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
282 static inline gboolean
283 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
285 return !((MonoThreadInfo*)info)->tools_thread;
289 Requires the world to be stoped
291 #define FOREACH_THREAD(thread) \
292 MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
294 #define FOREACH_THREAD_END \
300 #define FOREACH_THREAD_SAFE(thread) \
301 MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
303 #define FOREACH_THREAD_SAFE_END \
304 MONO_LLS_FOREACH_SAFE_END
306 static inline MonoNativeThreadId
307 mono_thread_info_get_tid (THREAD_INFO_TYPE *info)
309 return MONO_UINT_TO_NATIVE_THREAD_ID (((MonoThreadInfo*) info)->node.key);
313 mono_thread_info_set_tid (THREAD_INFO_TYPE *info, MonoNativeThreadId tid)
315 ((MonoThreadInfo*) info)->node.key = (uintptr_t) MONO_NATIVE_THREAD_ID_TO_UINT (tid);
319 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
320 * a single block with info from both camps.
323 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
326 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
328 MonoThreadInfoRuntimeCallbacks *
329 mono_threads_get_runtime_callbacks (void);
332 mono_thread_info_register_small_id (void);
335 mono_thread_info_attach (void *baseptr);
338 mono_thread_info_detach (void);
341 mono_thread_info_is_exiting (void);
344 mono_thread_info_current (void);
347 mono_thread_info_current_unchecked (void);
350 mono_thread_info_get_small_id (void);
353 mono_thread_info_list_head (void);
356 mono_thread_info_lookup (MonoNativeThreadId id);
359 mono_thread_info_resume (MonoNativeThreadId tid);
362 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
364 //XXX new API, fix the world
366 mono_thread_info_begin_self_suspend (void);
369 mono_thread_info_end_self_suspend (void);
374 mono_thread_info_unified_management_enabled (void);
377 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
380 mono_thread_info_suspend_lock (void);
383 mono_thread_info_suspend_unlock (void);
386 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
389 mono_thread_info_set_is_async_context (gboolean async_context);
392 mono_thread_info_is_async_context (void);
395 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
398 mono_thread_info_yield (void);
401 mono_thread_info_sleep (guint32 ms, gboolean *alerted);
404 mono_thread_info_usleep (guint64 us);
407 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
410 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
413 mono_thread_info_exit (void);
416 mono_thread_info_set_exited (THREAD_INFO_TYPE *info);
419 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
422 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
424 MonoThreadInfoInterruptToken*
425 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
428 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
431 mono_thread_info_self_interrupt (void);
434 mono_thread_info_clear_self_interrupt (void);
437 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
440 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
443 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
446 mono_threads_create_thread (MonoThreadStart start, gpointer arg, gsize stack_size, MonoNativeThreadId *out_tid);
449 mono_threads_get_max_stack_size (void);
452 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
455 mono_threads_close_thread_handle (HANDLE handle);
458 mono_threads_attach_tools_thread (void);
461 #if !defined(HOST_WIN32)
463 /*Use this instead of pthread_kill */
465 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
467 #endif /* !defined(HOST_WIN32) */
469 /* Internal API between mono-threads and its backends. */
471 /* Backend functions - a backend must implement all of the following */
473 This is called very early in the runtime, it cannot access any runtime facilities.
476 void mono_threads_suspend_init (void); //ok
478 void mono_threads_platform_init (void);
480 void mono_threads_coop_init (void);
482 void mono_threads_abort_syscall_init (void);
485 This begins async suspend. This function must do the following:
487 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
488 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
489 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
491 If begin suspend fails the thread must be left uninterrupted and resumed.
493 gboolean mono_threads_suspend_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
496 This verifies the outcome of an async suspend operation.
498 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
499 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
501 gboolean mono_threads_suspend_check_suspend_result (THREAD_INFO_TYPE *info);
504 This begins async resume. This function must do the following:
506 - Install an async target if one was requested.
507 - Notify the target to resume.
508 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
510 gboolean mono_threads_suspend_begin_async_resume (THREAD_INFO_TYPE *info);
512 void mono_threads_suspend_register (THREAD_INFO_TYPE *info); //ok
513 void mono_threads_suspend_free (THREAD_INFO_TYPE *info);
514 void mono_threads_suspend_abort_syscall (THREAD_INFO_TYPE *info);
515 gboolean mono_threads_suspend_needs_abort_syscall (void);
517 void mono_threads_platform_register (THREAD_INFO_TYPE *info);
518 void mono_threads_platform_unregister (THREAD_INFO_TYPE *info);
519 int mono_threads_platform_create_thread (MonoThreadStart thread_fn, gpointer thread_data, gsize stack_size, MonoNativeThreadId *out_tid);
520 void mono_threads_platform_get_stack_bounds (guint8 **staddr, size_t *stsize);
521 gboolean mono_threads_platform_yield (void);
522 void mono_threads_platform_exit (int exit_code);
523 HANDLE mono_threads_platform_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
524 void mono_threads_platform_close_thread_handle (HANDLE handle);
525 void mono_threads_platform_set_exited (gpointer handle);
526 gpointer mono_threads_platform_duplicate_handle (THREAD_INFO_TYPE *info);
528 void mono_threads_coop_begin_global_suspend (void);
529 void mono_threads_coop_end_global_suspend (void);
531 MONO_API MonoNativeThreadId
532 mono_native_thread_id_get (void);
535 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
538 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
541 mono_native_thread_set_name (MonoNativeThreadId tid, const char *name);
543 /*Mach specific internals */
544 void mono_threads_init_dead_letter (void);
545 void mono_threads_install_dead_letter (void);
547 /* mono-threads internal API used by the backends. */
549 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
551 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
553 This tells the resume initiator that we completed resume duties and will return to runnable state.
555 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
558 This tells the resume initiator that we completed abort duties and will return to previous state.
560 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
562 /* Thread state machine functions */
567 ResumeInitSelfResume,
568 ResumeInitAsyncResume,
569 ResumeInitBlockingResume,
575 SelfSuspendNotifyAndWait,
576 } MonoSelfSupendResult;
579 AsyncSuspendAlreadySuspended,
581 AsyncSuspendInitSuspend,
582 AsyncSuspendBlocking,
583 } MonoRequestAsyncSuspendResult;
586 DoBlockingContinue, //in blocking mode, continue
587 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
588 } MonoDoBlockingResult;
591 DoneBlockingOk, //exited blocking fine
592 DoneBlockingWait, //thread should end suspended
593 } MonoDoneBlockingResult;
597 AbortBlockingIgnore, //Ignore
598 AbortBlockingIgnoreAndPoll, //Ignore and poll
599 AbortBlockingOk, //Abort worked
600 AbortBlockingWait, //Abort worked, but should wait for resume
601 } MonoAbortBlockingResult;
604 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
605 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
606 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
607 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
608 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
609 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
610 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
611 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
612 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
613 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
615 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
618 mono_threads_enter_gc_unsafe_region_cookie (void);
621 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
622 /* Advanced suspend API, used for suspending multiple threads as once. */
623 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
624 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
625 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
626 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
627 const char* mono_thread_state_name (int state);
629 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
630 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
631 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
633 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
634 gboolean mono_threads_wait_pending_operations (void);
635 void mono_threads_begin_global_suspend (void);
636 void mono_threads_end_global_suspend (void);
639 mono_thread_info_is_current (THREAD_INFO_TYPE *info);
642 mono_thread_info_duplicate_handle (THREAD_INFO_TYPE *info);
644 #endif /* __MONO_THREADS_H__ */