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,
168 * This enum tells which async thread service corresponds to which bit.
171 MONO_SERVICE_REQUEST_SAMPLE = 1,
174 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
177 MonoLinkedListSetNode node;
178 guint32 small_id; /*Used by hazard pointers */
179 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
182 /*Tells if this thread was created by the runtime or not.*/
183 gboolean runtime_thread;
185 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
186 gboolean tools_thread;
188 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
189 void *stack_start_limit, *stack_end;
191 /* suspend machinery, fields protected by suspend_semaphore */
192 MonoSemType suspend_semaphore;
195 MonoSemType resume_semaphore;
197 /* only needed by the posix backend */
198 #if defined(USE_POSIX_BACKEND)
199 MonoSemType finish_resume_semaphore;
200 gboolean syscall_break_signal;
201 gboolean suspend_can_continue;
205 /* This memory pool is used by coop GC to save stack data roots between GC unsafe regions */
206 GByteArray *stackdata;
208 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
209 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
211 /*async call machinery, thread MUST be suspended before accessing those fields*/
212 void (*async_target)(void*);
216 If true, this thread is running a critical region of code and cannot be suspended.
217 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
218 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
220 gboolean inside_critical_region;
223 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
224 * operations like locking without having to pass an 'async' parameter around.
226 gboolean is_async_context;
228 gboolean create_suspended;
230 /* Semaphore used to implement CREATE_SUSPENDED */
231 MonoCoopSem create_suspended_sem;
234 * Values of TLS variables for this thread.
235 * This can be used to obtain the values of TLS variable for threads
236 * other than the current one.
238 gpointer tls [TLS_KEY_NUM];
240 /* IO layer handle for this thread */
241 /* Set when the thread is started, or in _wapi_thread_duplicate () */
244 /* 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.
245 * Use the mono_threads_add_async_job and mono_threads_consume_async_jobs APIs to modify this flag.
246 * In the future the signaling should be part of the API, but for now, it's only for massaging the bits.
248 volatile gint32 service_requests;
252 MonoThreadInfoInterruptToken *interrupt_token;
254 /* MonoHandleArena for coop handles */
255 gpointer handle_arena;
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 void (*thread_state_init) (MonoThreadUnwindState *tctx);
284 } MonoThreadInfoRuntimeCallbacks;
286 //Not using 0 and 1 to ensure callbacks are not returning bad data
288 MonoResumeThread = 0x1234,
289 KeepSuspended = 0x4321,
290 } SuspendThreadResult;
292 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
294 static inline gboolean
295 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
297 return !((MonoThreadInfo*)info)->tools_thread;
301 Requires the world to be stoped
303 #define FOREACH_THREAD(thread) \
304 MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
306 #define FOREACH_THREAD_END \
312 #define FOREACH_THREAD_SAFE(thread) \
313 MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), THREAD_INFO_TYPE, thread, mono_threads_filter_tools_threads)
315 #define FOREACH_THREAD_SAFE_END \
316 MONO_LLS_FOREACH_SAFE_END
318 static inline MonoNativeThreadId
319 mono_thread_info_get_tid (THREAD_INFO_TYPE *info)
321 return MONO_UINT_TO_NATIVE_THREAD_ID (((MonoThreadInfo*) info)->node.key);
325 mono_thread_info_set_tid (THREAD_INFO_TYPE *info, MonoNativeThreadId tid)
327 ((MonoThreadInfo*) info)->node.key = (uintptr_t) MONO_NATIVE_THREAD_ID_TO_UINT (tid);
331 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
332 * a single block with info from both camps.
335 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
338 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
340 MonoThreadInfoRuntimeCallbacks *
341 mono_threads_get_runtime_callbacks (void);
344 mono_thread_info_register_small_id (void);
347 mono_thread_info_attach (void *baseptr);
350 mono_thread_info_detach (void);
353 mono_thread_info_is_exiting (void);
356 mono_thread_info_current (void);
359 mono_thread_info_current_unchecked (void);
362 mono_thread_info_get_small_id (void);
365 mono_thread_info_list_head (void);
368 mono_thread_info_lookup (MonoNativeThreadId id);
371 mono_thread_info_resume (MonoNativeThreadId tid);
374 mono_thread_info_set_name (MonoNativeThreadId tid, const char *name);
377 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
379 //XXX new API, fix the world
381 mono_thread_info_begin_self_suspend (void);
384 mono_thread_info_end_self_suspend (void);
389 mono_thread_info_unified_management_enabled (void);
392 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
395 mono_thread_info_suspend_lock (void);
398 mono_thread_info_suspend_unlock (void);
401 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
404 mono_thread_info_set_is_async_context (gboolean async_context);
407 mono_thread_info_is_async_context (void);
410 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
413 mono_thread_info_yield (void);
416 mono_thread_info_sleep (guint32 ms, gboolean *alerted);
419 mono_thread_info_usleep (guint64 us);
422 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
425 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
428 mono_thread_info_exit (void);
431 mono_thread_info_open_handle (void);
434 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
437 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
439 MonoThreadInfoInterruptToken*
440 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
443 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
446 mono_thread_info_self_interrupt (void);
449 mono_thread_info_clear_self_interrupt (void);
452 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
455 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
458 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
461 mono_threads_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
464 mono_threads_get_max_stack_size (void);
467 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
470 This is the async job submission/consumption API.
471 XXX: This is a PROVISIONAL API only meant to be used by the statistical profiler.
472 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.
475 mono_threads_add_async_job (THREAD_INFO_TYPE *info, MonoAsyncJob job);
478 mono_threads_consume_async_jobs (void);
481 mono_threads_attach_tools_thread (void);
484 #if !defined(HOST_WIN32)
486 /*Use this instead of pthread_kill */
488 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
490 #endif /* !defined(HOST_WIN32) */
492 /* Internal API between mono-threads and its backends. */
494 /* Backend functions - a backend must implement all of the following */
496 This is called very early in the runtime, it cannot access any runtime facilities.
499 void mono_threads_init_platform (void); //ok
501 void mono_threads_init_coop (void);
503 void mono_threads_init_abort_syscall (void);
506 This begins async suspend. This function must do the following:
508 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
509 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
510 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
512 If begin suspend fails the thread must be left uninterrupted and resumed.
514 gboolean mono_threads_core_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
517 This verifies the outcome of an async suspend operation.
519 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
520 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
522 gboolean mono_threads_core_check_suspend_result (THREAD_INFO_TYPE *info);
525 This begins async resume. This function must do the following:
527 - Install an async target if one was requested.
528 - Notify the target to resume.
529 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
531 gboolean mono_threads_core_begin_async_resume (THREAD_INFO_TYPE *info);
533 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
534 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
535 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
536 gboolean mono_threads_core_needs_abort_syscall (void);
537 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
538 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
539 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
540 gboolean mono_threads_core_yield (void);
541 void mono_threads_core_exit (int exit_code);
542 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
543 HANDLE mono_threads_core_open_handle (void);
544 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
545 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
547 void mono_threads_coop_begin_global_suspend (void);
548 void mono_threads_coop_end_global_suspend (void);
551 mono_native_thread_id_get (void);
554 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
557 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
559 /*Mach specific internals */
560 void mono_threads_init_dead_letter (void);
561 void mono_threads_install_dead_letter (void);
563 /* mono-threads internal API used by the backends. */
565 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
567 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
569 This tells the resume initiator that we completed resume duties and will return to runnable state.
571 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
574 This tells the resume initiator that we completed abort duties and will return to previous state.
576 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
578 /* Thread state machine functions */
583 ResumeInitSelfResume,
584 ResumeInitAsyncResume,
585 ResumeInitBlockingResume,
591 SelfSuspendNotifyAndWait,
592 } MonoSelfSupendResult;
595 AsyncSuspendAlreadySuspended,
597 AsyncSuspendInitSuspend,
598 AsyncSuspendBlocking,
599 } MonoRequestAsyncSuspendResult;
602 DoBlockingContinue, //in blocking mode, continue
603 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
604 } MonoDoBlockingResult;
607 DoneBlockingAborted, //blocking was aborted and not properly restored, poll the state
608 DoneBlockingOk, //exited blocking fine
609 DoneBlockingWait, //thread should end suspended
610 } MonoDoneBlockingResult;
614 AbortBlockingIgnore, //Ignore
615 AbortBlockingIgnoreAndPoll, //Ignore and pool
616 AbortBlockingOk, //Abort worked
617 AbortBlockingOkAndPool, //Abort worked, but pool before
618 } MonoAbortBlockingResult;
621 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
622 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
623 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
624 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
625 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
626 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
627 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
628 void mono_threads_transition_async_suspend_compensation (THREAD_INFO_TYPE* info);
629 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
630 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
631 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
633 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
636 void mono_thread_info_wait_for_resume (THREAD_INFO_TYPE *info);
637 /* Advanced suspend API, used for suspending multiple threads as once. */
638 gboolean mono_thread_info_is_running (THREAD_INFO_TYPE *info);
639 gboolean mono_thread_info_is_live (THREAD_INFO_TYPE *info);
640 int mono_thread_info_suspend_count (THREAD_INFO_TYPE *info);
641 int mono_thread_info_current_state (THREAD_INFO_TYPE *info);
642 const char* mono_thread_state_name (int state);
644 gboolean mono_thread_info_in_critical_location (THREAD_INFO_TYPE *info);
645 gboolean mono_thread_info_begin_suspend (THREAD_INFO_TYPE *info);
646 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
649 mono_thread_info_check_suspend_result (THREAD_INFO_TYPE *info);
651 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
652 gboolean mono_threads_wait_pending_operations (void);
653 void mono_threads_begin_global_suspend (void);
654 void mono_threads_end_global_suspend (void);
656 #endif /* __MONO_THREADS_H__ */