示例#1
0
gboolean
mono_threads_core_begin_async_suspend (MonoThreadInfo *info, gboolean interrupt_kernel)
{
	kern_return_t ret;
	gboolean res;

	g_assert (info);

	ret = thread_suspend (info->native_handle);
	THREADS_SUSPEND_DEBUG ("SUSPEND %p -> %d\n", (void*)info->native_handle, ret);
	if (ret != KERN_SUCCESS)
		return FALSE;

	/* We're in the middle of a self-suspend, resume and register */
	if (!mono_threads_transition_finish_async_suspend (info)) {
		mono_threads_add_to_pending_operation_set (info);
		g_assert (thread_resume (info->native_handle) == KERN_SUCCESS);
		THREADS_SUSPEND_DEBUG ("FAILSAFE RESUME/1 %p -> %d\n", (void*)info->native_handle, 0);
		//XXX interrupt_kernel doesn't make sense in this case as the target is not in a syscall
		return TRUE;
	}
	res = mono_threads_get_runtime_callbacks ()->
		thread_state_init_from_handle (&info->thread_saved_state [ASYNC_SUSPEND_STATE_INDEX], info);
	THREADS_SUSPEND_DEBUG ("thread state %p -> %d\n", (void*)info->native_handle, res);
	if (res) {
		if (interrupt_kernel)
			thread_abort (info->native_handle);
	} else {
		mono_threads_transition_async_suspend_compensation (info);
		g_assert (thread_resume (info->native_handle) == KERN_SUCCESS);
		THREADS_SUSPEND_DEBUG ("FAILSAFE RESUME/2 %p -> %d\n", (void*)info->native_handle, 0);
	}
	return res;
}
gboolean
mono_threads_core_begin_async_suspend (MonoThreadInfo *info, gboolean interrupt_kernel)
{
	DWORD id = mono_thread_info_get_tid (info);
	HANDLE handle;
	DWORD result;
	gboolean res;

	handle = OpenThread (THREAD_ALL_ACCESS, FALSE, id);
	g_assert (handle);

	result = SuspendThread (handle);
	THREADS_SUSPEND_DEBUG ("SUSPEND %p -> %d\n", (void*)id, ret);
	if (result == (DWORD)-1) {
		CloseHandle (handle);
		return FALSE;
	}

	/* We're in the middle of a self-suspend, resume and register */
	if (!mono_threads_transition_finish_async_suspend (info)) {
		mono_threads_add_to_pending_operation_set (info);
		result = ResumeThread (handle);
		g_assert (result == 1);
		CloseHandle (handle);
		THREADS_SUSPEND_DEBUG ("FAILSAFE RESUME/1 %p -> %d\n", (void*)id, 0);
		//XXX interrupt_kernel doesn't make sense in this case as the target is not in a syscall
		return TRUE;
	}
	res = mono_threads_get_runtime_callbacks ()->thread_state_init_from_handle (&info->thread_saved_state [ASYNC_SUSPEND_STATE_INDEX], info);
	THREADS_SUSPEND_DEBUG ("thread state %p -> %d\n", (void*)id, res);
	if (res) {
		//FIXME do we need to QueueUserAPC on this case?
		if (interrupt_kernel)
			QueueUserAPC ((PAPCFUNC)interrupt_apc, handle, (ULONG_PTR)NULL);
	} else {
		mono_threads_transition_async_suspend_compensation (info);
		result = ResumeThread (handle);
		g_assert (result == 1);
		THREADS_SUSPEND_DEBUG ("FAILSAFE RESUME/2 %p -> %d\n", (void*)info->native_handle, 0);
	}

	CloseHandle (handle);
	return res;
}
static void
suspend_signal_handler (int _dummy, siginfo_t *info, void *context)
{
#if defined(__native_client__)
	g_assert_not_reached ();
#else
	int old_errno = errno;
	int hp_save_index = mono_hazard_pointer_save_for_signal_handler ();


	MonoThreadInfo *current = mono_thread_info_current ();
	gboolean ret;

	THREADS_SUSPEND_DEBUG ("SIGNAL HANDLER FOR %p [%p]\n", current, (void*)current->native_handle);
	if (current->syscall_break_signal) {
		current->syscall_break_signal = FALSE;
		THREADS_SUSPEND_DEBUG ("\tsyscall break for %p\n", current);
		mono_threads_notify_initiator_of_abort (current);
		goto done;
	}

	/* Have we raced with self suspend? */
	if (!mono_threads_transition_finish_async_suspend (current)) {
		current->suspend_can_continue = TRUE;
		THREADS_SUSPEND_DEBUG ("\tlost race with self suspend %p\n", current);
		goto done;
	}

	ret = mono_threads_get_runtime_callbacks ()->thread_state_init_from_sigctx (&current->thread_saved_state [ASYNC_SUSPEND_STATE_INDEX], context);

	/* thread_state_init_from_sigctx return FALSE if the current thread is detaching and suspend can't continue. */
	current->suspend_can_continue = ret;

	/*
	Block the restart signal.
	We need to block the restart signal while posting to the suspend_ack semaphore or we race to sigsuspend,
	which might miss the signal and get stuck.
	*/
	pthread_sigmask (SIG_BLOCK, &suspend_ack_signal_mask, NULL);

	/* This thread is doomed, all we can do is give up and let the suspender recover. */
	if (!ret) {
		THREADS_SUSPEND_DEBUG ("\tThread is dying, failed to capture state %p\n", current);
		mono_threads_transition_async_suspend_compensation (current);

		/* We're done suspending */
		mono_threads_notify_initiator_of_suspend (current);

		/* Unblock the restart signal. */
		pthread_sigmask (SIG_UNBLOCK, &suspend_ack_signal_mask, NULL);

		goto done;
	}

	/* We're done suspending */
	mono_threads_notify_initiator_of_suspend (current);

	do {
		current->signal = 0;
		sigsuspend (&suspend_signal_mask);
	} while (current->signal != restart_signal_num);

	/* Unblock the restart signal. */
	pthread_sigmask (SIG_UNBLOCK, &suspend_ack_signal_mask, NULL);

	if (current->async_target) {
#if MONO_ARCH_HAS_MONO_CONTEXT
		MonoContext tmp = current->thread_saved_state [ASYNC_SUSPEND_STATE_INDEX].ctx;
		mono_threads_get_runtime_callbacks ()->setup_async_callback (&tmp, current->async_target, current->user_data);
		current->async_target = current->user_data = NULL;
		mono_monoctx_to_sigctx (&tmp, context);
#else
		g_error ("The new interruption machinery requires a working mono-context");
#endif
	}

	/* We're done resuming */
	mono_threads_notify_initiator_of_resume (current);

done:
	mono_hazard_pointer_restore_for_signal_handler (hp_save_index);
	errno = old_errno;
#endif
}