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);
74 MONO_PREPARE_BLOCKING;
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));
149 /* Wait until the thread register itself in various places */
150 while (MONO_SEM_WAIT (&(start_info.registered)) != 0) {
151 /*if (EINTR != errno) ABORT("sem_wait failed"); */
153 MONO_FINISH_TRY_BLOCKING;
155 MONO_SEM_DESTROY (&(start_info.registered));
160 return start_info.handle;
164 * mono_threads_core_resume_created:
166 * Resume a newly created thread created using CREATE_SUSPENDED.
169 mono_threads_core_resume_created (MonoThreadInfo *info, MonoNativeThreadId tid)
171 MONO_SEM_POST (&info->create_suspended_sem);
175 mono_threads_core_yield (void)
177 return sched_yield () == 0;
181 mono_threads_core_exit (int exit_code)
183 MonoThreadInfo *current = mono_thread_info_current ();
185 #if defined(__native_client__)
186 nacl_shutdown_gc_thread();
189 wapi_thread_handle_set_exited (current->handle, exit_code);
191 mono_thread_info_detach ();
197 mono_threads_core_unregister (MonoThreadInfo *info)
200 wapi_thread_handle_set_exited (info->handle, 0);
206 mono_threads_core_open_handle (void)
208 MonoThreadInfo *info;
210 info = mono_thread_info_current ();
214 info->handle = wapi_create_thread_handle ();
216 wapi_ref_thread_handle (info->handle);
221 mono_threads_get_max_stack_size (void)
225 /* If getrlimit fails, we don't enforce any limits. */
226 if (getrlimit (RLIMIT_STACK, &lim))
228 /* rlim_t is an unsigned long long on 64bits OSX but we want an int response. */
229 if (lim.rlim_max > (rlim_t)INT_MAX)
231 return (int)lim.rlim_max;
235 mono_threads_core_open_thread_handle (HANDLE handle, MonoNativeThreadId tid)
237 wapi_ref_thread_handle (handle);
243 mono_threads_pthread_kill (MonoThreadInfo *info, int signum)
245 THREADS_SUSPEND_DEBUG ("sending signal %d to %p[%p]\n", signum, info, mono_thread_info_get_tid (info));
246 #ifdef USE_TKILL_ON_ANDROID
247 int result, old_errno = errno;
248 result = tkill (info->native_handle, signum);
254 #elif defined(__native_client__)
255 /* Workaround pthread_kill abort() in NaCl glibc. */
257 #elif !defined(HAVE_PTHREAD_KILL)
258 g_error ("pthread_kill() is not supported by this platform");
260 return pthread_kill (mono_thread_info_get_tid (info), signum);
265 mono_native_thread_id_get (void)
267 return pthread_self ();
271 mono_native_thread_id_equals (MonoNativeThreadId id1, MonoNativeThreadId id2)
273 return pthread_equal (id1, id2);
277 * mono_native_thread_create:
279 * Low level thread creation function without any GC wrappers.
282 mono_native_thread_create (MonoNativeThreadId *tid, gpointer func, gpointer arg)
284 return pthread_create (tid, NULL, (void *(*)(void *)) func, arg) == 0;
288 mono_threads_core_set_name (MonoNativeThreadId tid, const char *name)
290 #if defined (HAVE_PTHREAD_SETNAME_NP) && !defined (__MACH__)
292 pthread_setname_np (tid, "");
296 strncpy (n, name, 16);
298 pthread_setname_np (tid, n);
304 #if defined (USE_POSIX_BACKEND) && !defined (USE_COOP_GC)
306 static int suspend_signal_num;
307 static int restart_signal_num;
308 static int abort_signal_num;
309 static sigset_t suspend_signal_mask;
310 static sigset_t suspend_ack_signal_mask;
313 #if defined(__APPLE__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
314 #define DEFAULT_SUSPEND_SIGNAL SIGXFSZ
316 #define DEFAULT_SUSPEND_SIGNAL SIGPWR
318 #define DEFAULT_RESTART_SIGNAL SIGXCPU
321 mono_thread_search_alt_signal (int min_signal)
323 #if !defined (SIGRTMIN)
324 g_error ("signal search only works with RTMIN");
327 /* we try to avoid SIGRTMIN and any one that might have been set already, see bug #75387 */
328 for (i = MAX (min_signal, SIGRTMIN) + 1; i < SIGRTMAX; ++i) {
329 struct sigaction sinfo;
330 sigaction (i, NULL, &sinfo);
331 if (sinfo.sa_handler == SIG_DFL && (void*)sinfo.sa_sigaction == (void*)SIG_DFL) {
335 g_error ("Could not find an available signal");
340 mono_thread_get_alt_suspend_signal (void)
342 #if defined(PLATFORM_ANDROID)
344 #elif !defined (SIGRTMIN)
351 static int suspend_signum = -1;
352 if (suspend_signum == -1)
353 suspend_signum = mono_thread_search_alt_signal (-1);
354 return suspend_signum;
355 #endif /* SIGRTMIN */
359 mono_thread_get_alt_resume_signal (void)
361 #if defined(PLATFORM_ANDROID)
363 #elif !defined (SIGRTMIN)
370 static int resume_signum = -1;
371 if (resume_signum == -1)
372 resume_signum = mono_thread_search_alt_signal (mono_thread_get_alt_suspend_signal () + 1);
373 return resume_signum;
374 #endif /* SIGRTMIN */
379 mono_threads_get_abort_signal (void)
381 #if defined(PLATFORM_ANDROID)
383 #elif !defined (SIGRTMIN)
388 #endif /* SIGRTMIN */
390 static int abort_signum = -1;
391 if (abort_signum == -1)
392 abort_signum = mono_thread_search_alt_signal (mono_thread_get_alt_resume_signal () + 1);
394 #endif /* SIGRTMIN */
398 #if !defined(__native_client__)
400 restart_signal_handler (int _dummy, siginfo_t *_info, void *context)
402 MonoThreadInfo *info;
403 int old_errno = errno;
405 info = mono_thread_info_current ();
406 info->signal = restart_signal_num;
411 suspend_signal_handler (int _dummy, siginfo_t *info, void *context)
413 int old_errno = errno;
414 int hp_save_index = mono_hazard_pointer_save_for_signal_handler ();
417 MonoThreadInfo *current = mono_thread_info_current ();
420 THREADS_SUSPEND_DEBUG ("SIGNAL HANDLER FOR %p [%p]\n", current, (void*)current->native_handle);
421 if (current->syscall_break_signal) {
422 current->syscall_break_signal = FALSE;
423 THREADS_SUSPEND_DEBUG ("\tsyscall break for %p\n", current);
424 mono_threads_notify_initiator_of_abort (current);
428 /* Have we raced with self suspend? */
429 if (!mono_threads_transition_finish_async_suspend (current)) {
430 current->suspend_can_continue = TRUE;
431 THREADS_SUSPEND_DEBUG ("\tlost race with self suspend %p\n", current);
435 ret = mono_threads_get_runtime_callbacks ()->thread_state_init_from_sigctx (¤t->thread_saved_state [ASYNC_SUSPEND_STATE_INDEX], context);
437 /* thread_state_init_from_sigctx return FALSE if the current thread is detaching and suspend can't continue. */
438 current->suspend_can_continue = ret;
442 Block the restart signal.
443 We need to block the restart signal while posting to the suspend_ack semaphore or we race to sigsuspend,
444 which might miss the signal and get stuck.
446 pthread_sigmask (SIG_BLOCK, &suspend_ack_signal_mask, NULL);
448 /* We're done suspending */
449 mono_threads_notify_initiator_of_suspend (current);
451 /* This thread is doomed, all we can do is give up and let the suspender recover. */
453 THREADS_SUSPEND_DEBUG ("\tThread is dying, failed to capture state %p\n", current);
454 mono_threads_transition_async_suspend_compensation (current);
455 /* Unblock the restart signal. */
456 pthread_sigmask (SIG_UNBLOCK, &suspend_ack_signal_mask, NULL);
463 sigsuspend (&suspend_signal_mask);
464 } while (current->signal != restart_signal_num);
466 /* Unblock the restart signal. */
467 pthread_sigmask (SIG_UNBLOCK, &suspend_ack_signal_mask, NULL);
469 if (current->async_target) {
470 #if MONO_ARCH_HAS_MONO_CONTEXT
471 MonoContext tmp = current->thread_saved_state [ASYNC_SUSPEND_STATE_INDEX].ctx;
472 mono_threads_get_runtime_callbacks ()->setup_async_callback (&tmp, current->async_target, current->user_data);
473 current->async_target = current->user_data = NULL;
474 mono_monoctx_to_sigctx (&tmp, context);
476 g_error ("The new interruption machinery requires a working mono-context");
480 /* We're done resuming */
481 mono_threads_notify_initiator_of_resume (current);
484 mono_hazard_pointer_restore_for_signal_handler (hp_save_index);
489 abort_signal_handler (int _dummy, siginfo_t *info, void *context)
491 suspend_signal_handler (_dummy, info, context);
497 mono_posix_add_signal_handler (int signo, gpointer handler, int flags)
499 #if !defined(__native_client__)
500 /*FIXME, move the code from mini to utils and do the right thing!*/
502 struct sigaction previous_sa;
505 sa.sa_sigaction = handler;
506 sigfillset (&sa.sa_mask);
508 sa.sa_flags = SA_SIGINFO | flags;
509 ret = sigaction (signo, &sa, &previous_sa);
511 g_assert (ret != -1);
516 mono_threads_init_platform (void)
520 abort_signal_num = mono_threads_get_abort_signal ();
521 if (mono_thread_info_unified_management_enabled ()) {
522 suspend_signal_num = DEFAULT_SUSPEND_SIGNAL;
523 restart_signal_num = DEFAULT_RESTART_SIGNAL;
525 suspend_signal_num = mono_thread_get_alt_suspend_signal ();
526 restart_signal_num = mono_thread_get_alt_resume_signal ();
529 sigfillset (&suspend_signal_mask);
530 sigdelset (&suspend_signal_mask, restart_signal_num);
532 sigemptyset (&suspend_ack_signal_mask);
533 sigaddset (&suspend_ack_signal_mask, restart_signal_num);
535 mono_posix_add_signal_handler (suspend_signal_num, suspend_signal_handler, SA_RESTART);
536 mono_posix_add_signal_handler (restart_signal_num, restart_signal_handler, SA_RESTART);
537 mono_posix_add_signal_handler (abort_signal_num, abort_signal_handler, 0);
539 /* ensure all the new signals are unblocked */
540 sigemptyset (&signal_set);
541 sigaddset (&signal_set, suspend_signal_num);
542 sigaddset (&signal_set, restart_signal_num);
543 sigaddset (&signal_set, abort_signal_num);
544 sigprocmask (SIG_UNBLOCK, &signal_set, NULL);
548 mono_threads_core_abort_syscall (MonoThreadInfo *info)
551 We signal a thread to break it from the urrent syscall.
552 This signal should not be interpreted as a suspend request.
554 info->syscall_break_signal = TRUE;
555 if (!mono_threads_pthread_kill (info, abort_signal_num))
556 mono_threads_add_to_pending_operation_set (info);
560 mono_threads_core_needs_abort_syscall (void)
566 mono_threads_core_begin_async_suspend (MonoThreadInfo *info, gboolean interrupt_kernel)
568 int sig = interrupt_kernel ? abort_signal_num : suspend_signal_num;
570 if (!mono_threads_pthread_kill (info, sig)) {
571 mono_threads_add_to_pending_operation_set (info);
578 mono_threads_core_check_suspend_result (MonoThreadInfo *info)
580 return info->suspend_can_continue;
584 This begins async resume. This function must do the following:
586 - Install an async target if one was requested.
587 - Notify the target to resume.
590 mono_threads_core_begin_async_resume (MonoThreadInfo *info)
592 mono_threads_add_to_pending_operation_set (info);
593 return mono_threads_pthread_kill (info, restart_signal_num) == 0;
597 mono_threads_platform_register (MonoThreadInfo *info)
599 #if defined (PLATFORM_ANDROID)
600 info->native_handle = gettid ();
605 mono_threads_platform_free (MonoThreadInfo *info)
610 mono_threads_core_begin_global_suspend (void)
615 mono_threads_core_end_global_suspend (void)
619 #endif /*defined (USE_POSIX_BACKEND)*/