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;
197 gboolean suspend_can_continue;
199 /* This memory pool is used by coop GC to save stack data roots between GC unsafe regions */
200 GByteArray *stackdata;
202 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
203 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
205 /*async call machinery, thread MUST be suspended before accessing those fields*/
206 void (*async_target)(void*);
210 If true, this thread is running a critical region of code and cannot be suspended.
211 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
212 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
214 gboolean inside_critical_region;
217 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
218 * operations like locking without having to pass an 'async' parameter around.
220 gboolean is_async_context;
222 gboolean create_suspended;
224 /* Semaphore used to implement CREATE_SUSPENDED */
225 MonoCoopSem create_suspended_sem;
228 * Values of TLS variables for this thread.
229 * This can be used to obtain the values of TLS variable for threads
230 * other than the current one.
232 gpointer tls [TLS_KEY_NUM];
234 /* IO layer handle for this thread */
235 /* Set when the thread is started, or in _wapi_thread_duplicate () */
240 MonoThreadInfoInterruptToken *interrupt_token;
242 /* MonoHandleArena for coop handles */
243 gpointer handle_arena;
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_open_handle (void);
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 (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
449 mono_threads_get_max_stack_size (void);
452 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
455 mono_threads_attach_tools_thread (void);
458 #if !defined(HOST_WIN32)
460 /*Use this instead of pthread_kill */
462 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
464 #endif /* !defined(HOST_WIN32) */
466 /* Internal API between mono-threads and its backends. */
468 /* Backend functions - a backend must implement all of the following */
470 This is called very early in the runtime, it cannot access any runtime facilities.
473 void mono_threads_init_platform (void); //ok
475 void mono_threads_init_coop (void);
477 void mono_threads_init_abort_syscall (void);
480 This begins async suspend. This function must do the following:
482 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
483 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
484 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
486 If begin suspend fails the thread must be left uninterrupted and resumed.
488 gboolean mono_threads_core_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
491 This verifies the outcome of an async suspend operation.
493 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
494 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
496 gboolean mono_threads_core_check_suspend_result (THREAD_INFO_TYPE *info);
499 This begins async resume. This function must do the following:
501 - Install an async target if one was requested.
502 - Notify the target to resume.
503 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
505 gboolean mono_threads_core_begin_async_resume (THREAD_INFO_TYPE *info);
507 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
508 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
509 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
510 gboolean mono_threads_core_needs_abort_syscall (void);
511 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
512 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
513 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
514 gboolean mono_threads_core_yield (void);
515 void mono_threads_core_exit (int exit_code);
516 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
517 HANDLE mono_threads_core_open_handle (void);
518 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
520 void mono_threads_coop_begin_global_suspend (void);
521 void mono_threads_coop_end_global_suspend (void);
523 MONO_API MonoNativeThreadId
524 mono_native_thread_id_get (void);
527 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
530 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
533 mono_native_thread_set_name (MonoNativeThreadId tid, const char *name);
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 poll
592 AbortBlockingOk, //Abort worked
593 AbortBlockingWait, //Abort worked, but should wait for resume
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 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
605 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
606 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
608 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
611 mono_threads_enter_gc_unsafe_region_cookie (THREAD_INFO_TYPE *info);
614 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
615 /* Advanced suspend API, used for suspending multiple threads as once. */
616 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
617 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
618 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
619 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
620 const char* mono_thread_state_name (int state);
622 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
623 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
624 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
626 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
627 gboolean mono_threads_wait_pending_operations (void);
628 void mono_threads_begin_global_suspend (void);
629 void mono_threads_end_global_suspend (void);
631 #endif /* __MONO_THREADS_H__ */