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>
19 #include <mono/utils/mono-threads-api.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))
40 #include <mono/utils/mach-support.h>
42 typedef thread_port_t MonoNativeThreadHandle;
48 typedef pid_t MonoNativeThreadHandle;
50 #endif /* defined(__MACH__) */
52 typedef pthread_t MonoNativeThreadId;
54 typedef void* mono_native_thread_return_t;
56 #define MONO_NATIVE_THREAD_ID_TO_UINT(tid) (gsize)(tid)
57 #define MONO_UINT_TO_NATIVE_THREAD_ID(tid) (MonoNativeThreadId)(gsize)(tid)
59 #endif /* #ifdef HOST_WIN32 */
62 THREAD_INFO_TYPE is a way to make the mono-threads module parametric - or sort of.
63 The GC using mono-threads might extend the MonoThreadInfo struct to add its own
64 data, this avoid a pointer indirection on what is on a lot of hot paths.
66 But extending MonoThreadInfo has de disavantage that all functions here return type
67 would require a cast, something like the following:
75 ((MyThreadInfo*)mono_thread_info_current ())->stuff = 1;
77 While porting sgen to use mono-threads, the number of casts required was too much and
78 code ended up looking horrible. So we use this cute little hack. The idea is that
79 whomever is including this header can set the expected type to be used by functions here
80 and reduce the number of casts drastically.
83 #ifndef THREAD_INFO_TYPE
84 #define THREAD_INFO_TYPE MonoThreadInfo
87 /* Mono Threads internal configuration knows*/
89 /* Logging - enable them below if you need specific logging for the category you need */
90 #define MOSTLY_ASYNC_SAFE_PRINTF(...) do { \
91 char __buff[1024]; __buff [0] = '\0'; \
92 g_snprintf (__buff, sizeof (__buff), __VA_ARGS__); \
93 write (1, __buff, strlen (__buff)); \
98 #define THREADS_DEBUG(...)
100 #define THREADS_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
104 #define THREADS_STW_DEBUG(...)
106 #define THREADS_STW_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
110 #define THREADS_SUSPEND_DEBUG(...)
112 #define THREADS_SUSPEND_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
116 #define THREADS_STATE_MACHINE_DEBUG(...)
118 #define THREADS_STATE_MACHINE_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
122 #define THREADS_INTERRUPT_DEBUG(...)
124 #define THREADS_INTERRUPT_DEBUG MOSTLY_ASYNC_SAFE_PRINTF
127 /* If this is defined, use the signals backed on Mach. Debug only as signals can't be made usable on OSX. */
128 // #define USE_SIGNALS_ON_MACH
131 #if defined (USE_COOP_GC)
132 #define USE_COOP_BACKEND
133 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 1
135 #elif defined (_POSIX_VERSION) || defined (__native_client__)
136 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 0
138 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
139 #define USE_MACH_BACKEND
141 #define USE_POSIX_BACKEND
145 #define MONO_THREADS_PLATFORM_REQUIRES_UNIFIED_SUSPEND 0
146 #define USE_WINDOWS_BACKEND
149 #error "no backend support for current platform"
150 #endif /* defined (USE_COOP_GC) */
152 #if defined (_POSIX_VERSION) || defined (__native_client__)
153 #if defined (__MACH__) && !defined (USE_SIGNALS_ON_MACH)
154 #define USE_MACH_SYSCALL_ABORT
156 #define USE_POSIX_SYSCALL_ABORT
160 #define USE_WINDOWS_SYSCALL_ABORT
163 #error "no syscall abort support for current platform"
164 #endif /* defined (_POSIX_VERSION) || defined (__native_client__) */
167 STATE_STARTING = 0x00,
168 STATE_RUNNING = 0x01,
169 STATE_DETACHED = 0x02,
171 STATE_ASYNC_SUSPENDED = 0x03,
172 STATE_SELF_SUSPENDED = 0x04,
173 STATE_ASYNC_SUSPEND_REQUESTED = 0x05,
174 STATE_SELF_SUSPEND_REQUESTED = 0x06,
175 STATE_BLOCKING = 0x07,
176 STATE_BLOCKING_AND_SUSPENDED = 0x8,
180 THREAD_STATE_MASK = 0x00FF,
181 THREAD_SUSPEND_COUNT_MASK = 0xFF00,
182 THREAD_SUSPEND_COUNT_SHIFT = 8,
183 THREAD_SUSPEND_COUNT_MAX = 0xFF,
185 SELF_SUSPEND_STATE_INDEX = 0,
186 ASYNC_SUSPEND_STATE_INDEX = 1,
190 * This enum tells which async thread service corresponds to which bit.
193 MONO_SERVICE_REQUEST_SAMPLE = 1,
196 typedef struct _MonoThreadInfoInterruptToken MonoThreadInfoInterruptToken;
199 MonoLinkedListSetNode node;
200 guint32 small_id; /*Used by hazard pointers */
201 MonoNativeThreadHandle native_handle; /* Valid on mach and android */
204 /*Tells if this thread was created by the runtime or not.*/
205 gboolean runtime_thread;
207 /* Tells if this thread should be ignored or not by runtime services such as GC and profiling */
208 gboolean tools_thread;
210 /* Max stack bounds, all valid addresses must be between [stack_start_limit, stack_end[ */
211 void *stack_start_limit, *stack_end;
213 /* suspend machinery, fields protected by suspend_semaphore */
214 MonoSemType suspend_semaphore;
217 MonoSemType resume_semaphore;
219 /* only needed by the posix backend */
220 #if defined(USE_POSIX_BACKEND) || defined(USE_POSIX_SYSCALL_ABORT)
221 MonoSemType finish_resume_semaphore;
222 gboolean syscall_break_signal;
223 gboolean suspend_can_continue;
227 /*In theory, only the posix backend needs this, but having it on mach/win32 simplifies things a lot.*/
228 MonoThreadUnwindState thread_saved_state [2]; //0 is self suspend, 1 is async suspend.
230 /*async call machinery, thread MUST be suspended before accessing those fields*/
231 void (*async_target)(void*);
235 If true, this thread is running a critical region of code and cannot be suspended.
236 A critical session is implicitly started when you call mono_thread_info_safe_suspend_sync
237 and is ended when you call either mono_thread_info_resume or mono_thread_info_finish_suspend.
239 gboolean inside_critical_region;
242 * If TRUE, the thread is in async context. Code can use this information to avoid async-unsafe
243 * operations like locking without having to pass an 'async' parameter around.
245 gboolean is_async_context;
247 gboolean create_suspended;
249 /* Semaphore used to implement CREATE_SUSPENDED */
250 MonoSemType create_suspended_sem;
253 * Values of TLS variables for this thread.
254 * This can be used to obtain the values of TLS variable for threads
255 * other than the current one.
257 gpointer tls [TLS_KEY_NUM];
259 /* IO layer handle for this thread */
260 /* Set when the thread is started, or in _wapi_thread_duplicate () */
263 /* 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.
264 * Use the mono_threads_add_async_job and mono_threads_consume_async_jobs APIs to modify this flag.
265 * In the future the signaling should be part of the API, but for now, it's only for massaging the bits.
267 volatile gint32 service_requests;
271 MonoThreadInfoInterruptToken *interrupt_token;
275 void* (*thread_register)(THREAD_INFO_TYPE *info, void *baseaddr);
277 This callback is called with @info still on the thread list.
278 This call is made while holding the suspend lock, so don't do callbacks.
279 SMR remains functional as its small_id has not been reclaimed.
281 void (*thread_unregister)(THREAD_INFO_TYPE *info);
283 This callback is called right before thread_unregister. This is called
284 without any locks held so it's the place for complicated cleanup.
286 The thread must remain operational between this call and thread_unregister.
287 It must be possible to successfully suspend it after thread_unregister completes.
289 void (*thread_detach)(THREAD_INFO_TYPE *info);
290 void (*thread_attach)(THREAD_INFO_TYPE *info);
291 gboolean (*mono_method_is_critical) (void *method);
292 gboolean (*mono_thread_in_critical_region) (THREAD_INFO_TYPE *info);
293 } MonoThreadInfoCallbacks;
296 void (*setup_async_callback) (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data);
297 gboolean (*thread_state_init_from_sigctx) (MonoThreadUnwindState *state, void *sigctx);
298 gboolean (*thread_state_init_from_handle) (MonoThreadUnwindState *tctx, MonoThreadInfo *info);
299 void (*thread_state_init) (MonoThreadUnwindState *tctx);
300 } MonoThreadInfoRuntimeCallbacks;
302 //Not using 0 and 1 to ensure callbacks are not returning bad data
304 MonoResumeThread = 0x1234,
305 KeepSuspended = 0x4321,
306 } SuspendThreadResult;
308 typedef SuspendThreadResult (*MonoSuspendThreadCallback) (THREAD_INFO_TYPE *info, gpointer user_data);
310 static inline gboolean
311 mono_threads_filter_tools_threads (THREAD_INFO_TYPE *info)
313 return !((MonoThreadInfo*)info)->tools_thread;
317 Requires the world to be stoped
319 #define FOREACH_THREAD(thread) MONO_LLS_FOREACH_FILTERED (mono_thread_info_list_head (), thread, mono_threads_filter_tools_threads, THREAD_INFO_TYPE*)
320 #define END_FOREACH_THREAD MONO_LLS_END_FOREACH
325 #define FOREACH_THREAD_SAFE(thread) MONO_LLS_FOREACH_FILTERED_SAFE (mono_thread_info_list_head (), thread, mono_threads_filter_tools_threads, THREAD_INFO_TYPE*)
326 #define END_FOREACH_THREAD_SAFE MONO_LLS_END_FOREACH_SAFE
328 #define mono_thread_info_get_tid(info) ((MonoNativeThreadId)((MonoThreadInfo*)info)->node.key)
329 #define mono_thread_info_set_tid(info, val) do { ((MonoThreadInfo*)(info))->node.key = (uintptr_t)(val); } while (0)
332 * @thread_info_size is sizeof (GcThreadInfo), a struct the GC defines to make it possible to have
333 * a single block with info from both camps.
336 mono_threads_init (MonoThreadInfoCallbacks *callbacks, size_t thread_info_size);
339 mono_threads_runtime_init (MonoThreadInfoRuntimeCallbacks *callbacks);
341 MonoThreadInfoRuntimeCallbacks *
342 mono_threads_get_runtime_callbacks (void);
345 mono_thread_info_register_small_id (void);
348 mono_thread_info_attach (void *baseptr);
351 mono_thread_info_detach (void);
354 mono_thread_info_is_exiting (void);
357 mono_thread_info_current (void);
360 mono_thread_info_current_unchecked (void);
363 mono_thread_info_get_small_id (void);
366 mono_thread_info_list_head (void);
369 mono_thread_info_lookup (MonoNativeThreadId id);
372 mono_thread_info_safe_suspend_sync (MonoNativeThreadId tid, gboolean interrupt_kernel);
375 mono_thread_info_resume (MonoNativeThreadId tid);
378 mono_thread_info_set_name (MonoNativeThreadId tid, const char *name);
381 mono_thread_info_safe_suspend_and_run (MonoNativeThreadId id, gboolean interrupt_kernel, MonoSuspendThreadCallback callback, gpointer user_data);
383 //XXX new API, fix the world
385 mono_thread_info_begin_self_suspend (void);
388 mono_thread_info_end_self_suspend (void);
393 mono_thread_info_unified_management_enabled (void);
396 mono_thread_info_setup_async_call (THREAD_INFO_TYPE *info, void (*target_func)(void*), void *user_data);
399 mono_thread_info_suspend_lock (void);
402 mono_thread_info_suspend_unlock (void);
405 mono_thread_info_abort_socket_syscall_for_close (MonoNativeThreadId tid);
408 mono_thread_info_set_is_async_context (gboolean async_context);
411 mono_thread_info_is_async_context (void);
414 mono_thread_info_get_stack_bounds (guint8 **staddr, size_t *stsize);
417 mono_thread_info_yield (void);
420 mono_thread_info_tls_get (THREAD_INFO_TYPE *info, MonoTlsKey key);
423 mono_thread_info_tls_set (THREAD_INFO_TYPE *info, MonoTlsKey key, gpointer value);
426 mono_thread_info_exit (void);
429 mono_thread_info_open_handle (void);
432 mono_thread_info_install_interrupt (void (*callback) (gpointer data), gpointer data, gboolean *interrupted);
435 mono_thread_info_uninstall_interrupt (gboolean *interrupted);
437 MonoThreadInfoInterruptToken*
438 mono_thread_info_prepare_interrupt (THREAD_INFO_TYPE *info);
441 mono_thread_info_finish_interrupt (MonoThreadInfoInterruptToken *token);
444 mono_thread_info_self_interrupt (void);
447 mono_thread_info_clear_self_interrupt (void);
450 mono_thread_info_is_interrupt_state (THREAD_INFO_TYPE *info);
453 mono_thread_info_describe_interrupt_token (THREAD_INFO_TYPE *info, GString *text);
456 mono_thread_info_is_live (THREAD_INFO_TYPE *info);
459 mono_threads_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
462 mono_threads_get_max_stack_size (void);
465 mono_threads_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
468 This is the async job submission/consumption API.
469 XXX: This is a PROVISIONAL API only meant to be used by the statistical profiler.
470 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.
473 mono_threads_add_async_job (THREAD_INFO_TYPE *info, MonoAsyncJob job);
476 mono_threads_consume_async_jobs (void);
479 mono_threads_attach_tools_thread (void);
482 #if !defined(HOST_WIN32)
484 /*Use this instead of pthread_kill */
486 mono_threads_pthread_kill (THREAD_INFO_TYPE *info, int signum);
488 #endif /* !defined(HOST_WIN32) */
490 /* Internal API between mono-threads and its backends. */
492 /* Backend functions - a backend must implement all of the following */
494 This is called very early in the runtime, it cannot access any runtime facilities.
497 void mono_threads_init_platform (void); //ok
499 void mono_threads_init_abort_syscall (void);
502 This begins async suspend. This function must do the following:
504 -Ensure the target will EINTR any syscalls if @interrupt_kernel is true
505 -Call mono_threads_transition_finish_async_suspend as part of its async suspend.
506 -Register the thread for pending suspend with mono_threads_add_to_pending_operation_set if needed.
508 If begin suspend fails the thread must be left uninterrupted and resumed.
510 gboolean mono_threads_core_begin_async_suspend (THREAD_INFO_TYPE *info, gboolean interrupt_kernel);
513 This verifies the outcome of an async suspend operation.
515 Some targets, such as posix, verify suspend results assynchronously. Suspend results must be
516 available (in a non blocking way) after mono_threads_wait_pending_operations completes.
518 gboolean mono_threads_core_check_suspend_result (THREAD_INFO_TYPE *info);
521 This begins async resume. This function must do the following:
523 - Install an async target if one was requested.
524 - Notify the target to resume.
525 - Register the thread for pending ack with mono_threads_add_to_pending_operation_set if needed.
527 gboolean mono_threads_core_begin_async_resume (THREAD_INFO_TYPE *info);
529 void mono_threads_platform_register (THREAD_INFO_TYPE *info); //ok
530 void mono_threads_platform_free (THREAD_INFO_TYPE *info);
531 void mono_threads_core_abort_syscall (THREAD_INFO_TYPE *info);
532 gboolean mono_threads_core_needs_abort_syscall (void);
533 HANDLE mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid);
534 void mono_threads_core_resume_created (THREAD_INFO_TYPE *info, MonoNativeThreadId tid);
535 void mono_threads_core_get_stack_bounds (guint8 **staddr, size_t *stsize);
536 gboolean mono_threads_core_yield (void);
537 void mono_threads_core_exit (int exit_code);
538 void mono_threads_core_unregister (THREAD_INFO_TYPE *info);
539 HANDLE mono_threads_core_open_handle (void);
540 HANDLE mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid);
541 void mono_threads_core_set_name (MonoNativeThreadId tid, const char *name);
543 void mono_threads_core_begin_global_suspend (void);
544 void mono_threads_core_end_global_suspend (void);
546 MonoNativeThreadId mono_native_thread_id_get (void);
548 gboolean mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2);
551 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg);
553 /*Mach specific internals */
554 void mono_threads_init_dead_letter (void);
555 void mono_threads_install_dead_letter (void);
557 /* mono-threads internal API used by the backends. */
559 This tells the suspend initiator that we completed suspend and will now be waiting for resume.
561 void mono_threads_notify_initiator_of_suspend (THREAD_INFO_TYPE* info);
563 This tells the resume initiator that we completed resume duties and will return to runnable state.
565 void mono_threads_notify_initiator_of_resume (THREAD_INFO_TYPE* info);
568 This tells the resume initiator that we completed abort duties and will return to previous state.
570 void mono_threads_notify_initiator_of_abort (THREAD_INFO_TYPE* info);
572 /* Thread state machine functions */
577 ResumeInitSelfResume,
578 ResumeInitAsyncResume,
579 ResumeInitBlockingResume,
585 SelfSuspendNotifyAndWait,
586 } MonoSelfSupendResult;
589 AsyncSuspendAlreadySuspended,
591 AsyncSuspendInitSuspend,
592 } MonoRequestAsyncSuspendResult;
595 DoBlockingContinue, //in blocking mode, continue
596 DoBlockingPollAndRetry, //async suspend raced blocking and won, pool and retry
597 } MonoDoBlockingResult;
600 DoneBlockingAborted, //blocking was aborted and not properly restored, poll the state
601 DoneBlockingOk, //exited blocking fine
602 DoneBlockingWait, //thread should end suspended
603 } MonoDoneBlockingResult;
607 AbortBlockingIgnore, //Ignore
608 AbortBlockingIgnoreAndPoll, //Ignore and pool
609 AbortBlockingOk, //Abort worked
610 AbortBlockingOkAndPool, //Abort worked, but pool before
611 } MonoAbortBlockingResult;
614 void mono_threads_transition_attach (THREAD_INFO_TYPE* info);
615 gboolean mono_threads_transition_detach (THREAD_INFO_TYPE *info);
616 void mono_threads_transition_request_self_suspension (THREAD_INFO_TYPE *info);
617 MonoRequestAsyncSuspendResult mono_threads_transition_request_async_suspension (THREAD_INFO_TYPE *info);
618 MonoSelfSupendResult mono_threads_transition_state_poll (THREAD_INFO_TYPE *info);
619 MonoResumeResult mono_threads_transition_request_resume (THREAD_INFO_TYPE* info);
620 gboolean mono_threads_transition_finish_async_suspend (THREAD_INFO_TYPE* info);
621 void mono_threads_transition_async_suspend_compensation (THREAD_INFO_TYPE* info);
622 MonoDoBlockingResult mono_threads_transition_do_blocking (THREAD_INFO_TYPE* info);
623 MonoDoneBlockingResult mono_threads_transition_done_blocking (THREAD_INFO_TYPE* info);
624 MonoAbortBlockingResult mono_threads_transition_abort_blocking (THREAD_INFO_TYPE* info);
626 MonoThreadUnwindState* mono_thread_info_get_suspend_state (THREAD_INFO_TYPE *info);
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, gboolean interrupt_kernel);
639 gboolean mono_thread_info_begin_resume (THREAD_INFO_TYPE *info);
642 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
643 gboolean mono_threads_wait_pending_operations (void);
644 void mono_threads_begin_global_suspend (void);
645 void mono_threads_end_global_suspend (void);
647 #endif /* __MONO_THREADS_H__ */