2 * mono-threads-posix.c: Low-level threading, posix version
5 * Rodrigo Kumpera (kumpera@gmail.com)
12 /* For pthread_main_np, pthread_get_stackaddr_np and pthread_get_stacksize_np */
13 #if defined (__MACH__)
14 #define _DARWIN_C_SOURCE 1
17 #include <mono/utils/mono-compiler.h>
18 #include <mono/utils/mono-semaphore.h>
19 #include <mono/utils/mono-threads.h>
20 #include <mono/utils/mono-tls.h>
21 #include <mono/utils/mono-mmap.h>
22 #include <mono/metadata/threads-types.h>
23 #include <mono/metadata/gc-internal.h>
28 #if defined(PLATFORM_ANDROID) && !defined(TARGET_ARM64) && !defined(TARGET_AMD64)
29 #define USE_TKILL_ON_ANDROID 1
32 #ifdef USE_TKILL_ON_ANDROID
33 extern int tkill (pid_t tid, int signal);
36 #if defined(_POSIX_VERSION) || defined(__native_client__)
37 #include <sys/resource.h>
40 #if defined(__native_client__)
41 void nacl_shutdown_gc_thread(void);
45 void *(*start_routine)(void*);
48 MonoSemType registered;
53 inner_start_thread (void *arg)
55 StartInfo *start_info = (StartInfo *) arg;
56 void *t_arg = start_info->arg;
58 void *(*start_func)(void*) = start_info->start_routine;
59 guint32 flags = start_info->flags;
64 /* Register the thread with the io-layer */
65 handle = wapi_create_thread_handle ();
67 res = MONO_SEM_POST (&(start_info->registered));
71 start_info->handle = handle;
73 info = mono_thread_info_attach (&result);
76 info->runtime_thread = TRUE;
77 info->handle = handle;
79 if (flags & CREATE_SUSPENDED) {
80 info->create_suspended = TRUE;
81 MONO_SEM_INIT (&info->create_suspended_sem, 0);
84 /* start_info is not valid after this */
85 res = MONO_SEM_POST (&(start_info->registered));
89 if (flags & CREATE_SUSPENDED) {
90 while (MONO_SEM_WAIT (&info->create_suspended_sem) != 0 &&
92 MONO_SEM_DESTROY (&info->create_suspended_sem);
96 /* Run the actual main function of the thread */
97 result = start_func (t_arg);
99 mono_threads_core_exit (GPOINTER_TO_UINT (result));
100 g_assert_not_reached ();
104 mono_threads_core_create_thread (LPTHREAD_START_ROUTINE start_routine, gpointer arg, guint32 stack_size, guint32 creation_flags, MonoNativeThreadId *out_tid)
109 StartInfo start_info;
111 res = pthread_attr_init (&attr);
114 if (stack_size == 0) {
115 #if HAVE_VALGRIND_MEMCHECK_H
116 if (RUNNING_ON_VALGRIND)
117 stack_size = 1 << 20;
119 stack_size = (SIZEOF_VOID_P / 4) * 1024 * 1024;
121 stack_size = (SIZEOF_VOID_P / 4) * 1024 * 1024;
125 #ifdef PTHREAD_STACK_MIN
126 if (stack_size < PTHREAD_STACK_MIN)
127 stack_size = PTHREAD_STACK_MIN;
130 #ifdef HAVE_PTHREAD_ATTR_SETSTACKSIZE
131 res = pthread_attr_setstacksize (&attr, stack_size);
135 memset (&start_info, 0, sizeof (StartInfo));
136 start_info.start_routine = (void *(*)(void *)) start_routine;
137 start_info.arg = arg;
138 start_info.flags = creation_flags;
139 MONO_SEM_INIT (&(start_info.registered), 0);
141 /* Actually start the thread */
142 res = mono_gc_pthread_create (&thread, &attr, inner_start_thread, &start_info);
144 MONO_SEM_DESTROY (&(start_info.registered));
148 /* Wait until the thread register itself in various places */
149 while (MONO_SEM_WAIT (&(start_info.registered)) != 0) {
150 /*if (EINTR != errno) ABORT("sem_wait failed"); */
152 MONO_SEM_DESTROY (&(start_info.registered));
157 return start_info.handle;
161 * mono_threads_core_resume_created:
163 * Resume a newly created thread created using CREATE_SUSPENDED.
166 mono_threads_core_resume_created (MonoThreadInfo *info, MonoNativeThreadId tid)
168 MONO_SEM_POST (&info->create_suspended_sem);
172 mono_threads_core_yield (void)
174 return sched_yield () == 0;
178 mono_threads_core_exit (int exit_code)
180 MonoThreadInfo *current = mono_thread_info_current ();
182 #if defined(__native_client__)
183 nacl_shutdown_gc_thread();
186 wapi_thread_handle_set_exited (current->handle, exit_code);
188 mono_thread_info_detach ();
194 mono_threads_core_unregister (MonoThreadInfo *info)
197 wapi_thread_handle_set_exited (info->handle, 0);
203 mono_threads_core_open_handle (void)
205 MonoThreadInfo *info;
207 info = mono_thread_info_current ();
211 info->handle = wapi_create_thread_handle ();
213 wapi_ref_thread_handle (info->handle);
218 mono_threads_get_max_stack_size (void)
222 /* If getrlimit fails, we don't enforce any limits. */
223 if (getrlimit (RLIMIT_STACK, &lim))
225 /* rlim_t is an unsigned long long on 64bits OSX but we want an int response. */
226 if (lim.rlim_max > (rlim_t)INT_MAX)
228 return (int)lim.rlim_max;
232 mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid)
234 wapi_ref_thread_handle (handle);
240 mono_threads_core_prepare_interrupt (HANDLE thread_handle)
242 return wapi_prepare_interrupt_thread (thread_handle);
246 mono_threads_core_finish_interrupt (gpointer wait_handle)
248 wapi_finish_interrupt_thread (wait_handle);
252 mono_threads_core_self_interrupt (void)
254 wapi_self_interrupt ();
258 mono_threads_core_clear_interruption (void)
260 wapi_clear_interruption ();
264 mono_threads_pthread_kill (MonoThreadInfo *info, int signum)
266 THREADS_SUSPEND_DEBUG ("sending signal %d to %p[%p]\n", signum, info, mono_thread_info_get_tid (info));
267 #ifdef USE_TKILL_ON_ANDROID
268 int result, old_errno = errno;
269 result = tkill (info->native_handle, signum);
275 #elif defined(__native_client__)
276 /* Workaround pthread_kill abort() in NaCl glibc. */
279 return pthread_kill (mono_thread_info_get_tid (info), signum);
284 mono_native_thread_id_get (void)
286 return pthread_self ();
290 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2)
292 return pthread_equal (id1, id2);
296 * mono_native_thread_create:
298 * Low level thread creation function without any GC wrappers.
301 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg)
303 return pthread_create (tid, NULL, (void *(*)(void *)) func, arg) == 0;
307 mono_threads_core_set_name (MonoNativeThreadId tid, const char *name)
309 #if defined (HAVE_PTHREAD_SETNAME_NP) && !defined (__MACH__)
311 pthread_setname_np (tid, "");
315 strncpy (n, name, 16);
317 pthread_setname_np (tid, n);
323 #if defined (USE_POSIX_BACKEND) && !defined (USE_COOP_GC)
325 static int suspend_signal_num;
326 static int restart_signal_num;
327 static int abort_signal_num;
328 static sigset_t suspend_signal_mask;
329 static sigset_t suspend_ack_signal_mask;
332 #if defined(__APPLE__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
333 #define DEFAULT_SUSPEND_SIGNAL SIGXFSZ
335 #define DEFAULT_SUSPEND_SIGNAL SIGPWR
337 #define DEFAULT_RESTART_SIGNAL SIGXCPU
340 mono_thread_search_alt_signal (int min_signal)
342 #if !defined (SIGRTMIN)
343 g_error ("signal search only works with RTMIN");
346 /* we try to avoid SIGRTMIN and any one that might have been set already, see bug #75387 */
347 for (i = MAX (min_signal, SIGRTMIN) + 1; i < SIGRTMAX; ++i) {
348 struct sigaction sinfo;
349 sigaction (i, NULL, &sinfo);
350 if (sinfo.sa_handler == SIG_DFL && (void*)sinfo.sa_sigaction == (void*)SIG_DFL) {
354 g_error ("Could not find an available signal");
359 mono_thread_get_alt_suspend_signal (void)
361 #if defined(PLATFORM_ANDROID)
363 #elif !defined (SIGRTMIN)
370 static int suspend_signum = -1;
371 if (suspend_signum == -1)
372 suspend_signum = mono_thread_search_alt_signal (-1);
373 return suspend_signum;
374 #endif /* SIGRTMIN */
378 mono_thread_get_alt_resume_signal (void)
380 #if defined(PLATFORM_ANDROID)
382 #elif !defined (SIGRTMIN)
389 static int resume_signum = -1;
390 if (resume_signum == -1)
391 resume_signum = mono_thread_search_alt_signal (mono_thread_get_alt_suspend_signal () + 1);
392 return resume_signum;
393 #endif /* SIGRTMIN */
398 mono_threads_get_abort_signal (void)
400 #if defined(PLATFORM_ANDROID)
402 #elif !defined (SIGRTMIN)
407 #endif /* SIGRTMIN */
409 static int abort_signum = -1;
410 if (abort_signum == -1)
411 abort_signum = mono_thread_search_alt_signal (mono_thread_get_alt_resume_signal () + 1);
413 #endif /* SIGRTMIN */
417 #if !defined(__native_client__)
419 restart_signal_handler (int _dummy, siginfo_t *_info, void *context)
421 MonoThreadInfo *info;
422 int old_errno = errno;
424 info = mono_thread_info_current ();
425 info->signal = restart_signal_num;
430 suspend_signal_handler (int _dummy, siginfo_t *info, void *context)
432 int old_errno = errno;
433 int hp_save_index = mono_hazard_pointer_save_for_signal_handler ();
436 MonoThreadInfo *current = mono_thread_info_current ();
439 THREADS_SUSPEND_DEBUG ("SIGNAL HANDLER FOR %p [%p]\n", current, (void*)current->native_handle);
440 if (current->syscall_break_signal) {
441 current->syscall_break_signal = FALSE;
442 THREADS_SUSPEND_DEBUG ("\tsyscall break for %p\n", current);
443 mono_threads_notify_initiator_of_abort (current);
447 /* Have we raced with self suspend? */
448 if (!mono_threads_transition_finish_async_suspend (current)) {
449 current->suspend_can_continue = TRUE;
450 THREADS_SUSPEND_DEBUG ("\tlost race with self suspend %p\n", current);
454 ret = mono_threads_get_runtime_callbacks ()->thread_state_init_from_sigctx (¤t->thread_saved_state [ASYNC_SUSPEND_STATE_INDEX], context);
456 /* thread_state_init_from_sigctx return FALSE if the current thread is detaching and suspend can't continue. */
457 current->suspend_can_continue = ret;
461 Block the restart signal.
462 We need to block the restart signal while posting to the suspend_ack semaphore or we race to sigsuspend,
463 which might miss the signal and get stuck.
465 pthread_sigmask (SIG_BLOCK, &suspend_ack_signal_mask, NULL);
467 /* We're done suspending */
468 mono_threads_notify_initiator_of_suspend (current);
470 /* This thread is doomed, all we can do is give up and let the suspender recover. */
472 THREADS_SUSPEND_DEBUG ("\tThread is dying, failed to capture state %p\n", current);
473 mono_threads_transition_async_suspend_compensation (current);
474 /* Unblock the restart signal. */
475 pthread_sigmask (SIG_UNBLOCK, &suspend_ack_signal_mask, NULL);
482 sigsuspend (&suspend_signal_mask);
483 } while (current->signal != restart_signal_num);
485 /* Unblock the restart signal. */
486 pthread_sigmask (SIG_UNBLOCK, &suspend_ack_signal_mask, NULL);
488 if (current->async_target) {
489 #if MONO_ARCH_HAS_MONO_CONTEXT
490 MonoContext tmp = current->thread_saved_state [ASYNC_SUSPEND_STATE_INDEX].ctx;
491 mono_threads_get_runtime_callbacks ()->setup_async_callback (&tmp, current->async_target, current->user_data);
492 current->async_target = current->user_data = NULL;
493 mono_monoctx_to_sigctx (&tmp, context);
495 g_error ("The new interruption machinery requires a working mono-context");
499 /* We're done resuming */
500 mono_threads_notify_initiator_of_resume (current);
503 mono_hazard_pointer_restore_for_signal_handler (hp_save_index);
508 abort_signal_handler (int _dummy, siginfo_t *info, void *context)
510 suspend_signal_handler (_dummy, info, context);
516 mono_posix_add_signal_handler (int signo, gpointer handler, int flags)
518 #if !defined(__native_client__)
519 /*FIXME, move the code from mini to utils and do the right thing!*/
521 struct sigaction previous_sa;
524 sa.sa_sigaction = handler;
525 sigfillset (&sa.sa_mask);
527 sa.sa_flags = SA_SIGINFO | flags;
528 ret = sigaction (signo, &sa, &previous_sa);
530 g_assert (ret != -1);
535 mono_threads_init_platform (void)
539 abort_signal_num = mono_threads_get_abort_signal ();
540 if (mono_thread_info_unified_management_enabled ()) {
541 suspend_signal_num = DEFAULT_SUSPEND_SIGNAL;
542 restart_signal_num = DEFAULT_RESTART_SIGNAL;
544 suspend_signal_num = mono_thread_get_alt_suspend_signal ();
545 restart_signal_num = mono_thread_get_alt_resume_signal ();
548 sigfillset (&suspend_signal_mask);
549 sigdelset (&suspend_signal_mask, restart_signal_num);
551 sigemptyset (&suspend_ack_signal_mask);
552 sigaddset (&suspend_ack_signal_mask, restart_signal_num);
554 mono_posix_add_signal_handler (suspend_signal_num, suspend_signal_handler, SA_RESTART);
555 mono_posix_add_signal_handler (restart_signal_num, restart_signal_handler, SA_RESTART);
556 mono_posix_add_signal_handler (abort_signal_num, abort_signal_handler, 0);
558 /* ensure all the new signals are unblocked */
559 sigemptyset (&signal_set);
560 sigaddset (&signal_set, suspend_signal_num);
561 sigaddset (&signal_set, restart_signal_num);
562 sigaddset (&signal_set, abort_signal_num);
563 sigprocmask (SIG_UNBLOCK, &signal_set, NULL);
567 mono_threads_core_abort_syscall (MonoThreadInfo *info)
570 We signal a thread to break it from the urrent syscall.
571 This signal should not be interpreted as a suspend request.
573 info->syscall_break_signal = TRUE;
574 if (!mono_threads_pthread_kill (info, abort_signal_num))
575 mono_threads_add_to_pending_operation_set (info);
579 mono_threads_core_needs_abort_syscall (void)
585 mono_threads_core_begin_async_suspend (MonoThreadInfo *info, gboolean interrupt_kernel)
587 int sig = interrupt_kernel ? abort_signal_num : suspend_signal_num;
589 if (!mono_threads_pthread_kill (info, sig)) {
590 mono_threads_add_to_pending_operation_set (info);
597 mono_threads_core_check_suspend_result (MonoThreadInfo *info)
599 return info->suspend_can_continue;
603 This begins async resume. This function must do the following:
605 - Install an async target if one was requested.
606 - Notify the target to resume.
609 mono_threads_core_begin_async_resume (MonoThreadInfo *info)
611 mono_threads_add_to_pending_operation_set (info);
612 return mono_threads_pthread_kill (info, restart_signal_num) == 0;
616 mono_threads_platform_register (MonoThreadInfo *info)
618 #if defined (PLATFORM_ANDROID)
619 info->native_handle = gettid ();
624 mono_threads_platform_free (MonoThreadInfo *info)
629 mono_threads_core_begin_global_suspend (void)
634 mono_threads_core_end_global_suspend (void)
638 #endif /*defined (USE_POSIX_BACKEND)*/