Esempio n. 1
0
/*
 * Create a new thread.
 * Doesn't start the thread running.
 */
static kern_return_t
thread_create_internal(
	task_t					parent_task,
	integer_t				priority,
	thread_continue_t		continuation,
	int						options,
#define TH_OPTION_NONE		0x00
#define TH_OPTION_NOCRED	0x01
#define TH_OPTION_NOSUSP	0x02
	thread_t				*out_thread)
{
	thread_t				new_thread;
	static thread_t			first_thread = THREAD_NULL;

	/*
	 *	Allocate a thread and initialize static fields
	 */
	if (first_thread == THREAD_NULL)
		new_thread = first_thread = current_thread();
	new_thread = (thread_t)zalloc(thread_zone);
	if (new_thread == THREAD_NULL)
		return (KERN_RESOURCE_SHORTAGE);

	if (new_thread != first_thread)
		*new_thread = thread_template;

#ifdef MACH_BSD
	new_thread->uthread = uthread_alloc(parent_task, new_thread, (options & TH_OPTION_NOCRED) != 0);
	if (new_thread->uthread == NULL) {
		zfree(thread_zone, new_thread);
		return (KERN_RESOURCE_SHORTAGE);
	}
#endif  /* MACH_BSD */

	if (machine_thread_create(new_thread, parent_task) != KERN_SUCCESS) {
#ifdef MACH_BSD
		void *ut = new_thread->uthread;

		new_thread->uthread = NULL;
		/* cred free may not be necessary */
		uthread_cleanup(parent_task, ut, parent_task->bsd_info);
		uthread_cred_free(ut);
		uthread_zone_free(ut);
#endif  /* MACH_BSD */

		zfree(thread_zone, new_thread);
		return (KERN_FAILURE);
	}

	new_thread->task = parent_task;

	thread_lock_init(new_thread);
	wake_lock_init(new_thread);

	lck_mtx_init(&new_thread->mutex, &thread_lck_grp, &thread_lck_attr);

	ipc_thread_init(new_thread);
	queue_init(&new_thread->held_ulocks);

	new_thread->continuation = continuation;

	lck_mtx_lock(&tasks_threads_lock);
	task_lock(parent_task);

	if (	!parent_task->active || parent_task->halting ||
			((options & TH_OPTION_NOSUSP) != 0 &&
			 	parent_task->suspend_count > 0)	||
			(parent_task->thread_count >= task_threadmax &&
				parent_task != kernel_task)		) {
		task_unlock(parent_task);
		lck_mtx_unlock(&tasks_threads_lock);

#ifdef MACH_BSD
		{
			void *ut = new_thread->uthread;

			new_thread->uthread = NULL;
			uthread_cleanup(parent_task, ut, parent_task->bsd_info);
			/* cred free may not be necessary */
			uthread_cred_free(ut);
			uthread_zone_free(ut);
		}
#endif  /* MACH_BSD */
		ipc_thread_disable(new_thread);
		ipc_thread_terminate(new_thread);
		lck_mtx_destroy(&new_thread->mutex, &thread_lck_grp);
		machine_thread_destroy(new_thread);
		zfree(thread_zone, new_thread);
		return (KERN_FAILURE);
	}

	/* New threads inherit any default state on the task */
	machine_thread_inherit_taskwide(new_thread, parent_task);

	task_reference_internal(parent_task);

	if (new_thread->task->rusage_cpu_flags & TASK_RUSECPU_FLAGS_PERTHR_LIMIT) {
		/*
		 * This task has a per-thread CPU limit; make sure this new thread
		 * gets its limit set too, before it gets out of the kernel.
		 */
		set_astledger(new_thread);
	}
	new_thread->t_threadledger = LEDGER_NULL;	/* per thread ledger is not inherited */
	new_thread->t_ledger = new_thread->task->ledger;
	if (new_thread->t_ledger)
		ledger_reference(new_thread->t_ledger);

	/* Cache the task's map */
	new_thread->map = parent_task->map;

	/* Chain the thread onto the task's list */
	queue_enter(&parent_task->threads, new_thread, thread_t, task_threads);
	parent_task->thread_count++;
	
	/* So terminating threads don't need to take the task lock to decrement */
	hw_atomic_add(&parent_task->active_thread_count, 1);

	/* Protected by the tasks_threads_lock */
	new_thread->thread_id = ++thread_unique_id;

	queue_enter(&threads, new_thread, thread_t, threads);
	threads_count++;

	timer_call_setup(&new_thread->wait_timer, thread_timer_expire, new_thread);
	timer_call_setup(&new_thread->depress_timer, thread_depress_expire, new_thread);

#if CONFIG_COUNTERS
	/*
	 * If parent task has any reservations, they need to be propagated to this
	 * thread.
	 */
	new_thread->t_chud = (TASK_PMC_FLAG == (parent_task->t_chud & TASK_PMC_FLAG)) ? 
		THREAD_PMC_FLAG : 0U;
#endif

	/* Set the thread's scheduling parameters */
	new_thread->sched_mode = SCHED(initial_thread_sched_mode)(parent_task);
	new_thread->sched_flags = 0;
	new_thread->max_priority = parent_task->max_priority;
	new_thread->task_priority = parent_task->priority;
	new_thread->priority = (priority < 0)? parent_task->priority: priority;
	if (new_thread->priority > new_thread->max_priority)
		new_thread->priority = new_thread->max_priority;
#if CONFIG_EMBEDDED 
	if (new_thread->priority < MAXPRI_THROTTLE) {
		new_thread->priority = MAXPRI_THROTTLE;
	}
#endif /* CONFIG_EMBEDDED */
	new_thread->importance =
					new_thread->priority - new_thread->task_priority;
#if CONFIG_EMBEDDED
	new_thread->saved_importance = new_thread->importance;
	/* apple ios daemon starts all threads in darwin background */
	if (parent_task->ext_appliedstate.apptype == PROC_POLICY_IOS_APPLE_DAEMON) {
		/* Cannot use generic routines here so apply darwin bacground directly */
		new_thread->policystate.hw_bg = TASK_POLICY_BACKGROUND_ATTRIBUTE_ALL;
		/* set thread self backgrounding */
		new_thread->appliedstate.hw_bg = new_thread->policystate.hw_bg;
		/* priority will get recomputed suitably bit later */
		new_thread->importance = INT_MIN;
		/* to avoid changes to many pri compute routines, set the effect of those here */
		new_thread->priority = MAXPRI_THROTTLE;
	}
#endif /* CONFIG_EMBEDDED */

#if defined(CONFIG_SCHED_TRADITIONAL)
	new_thread->sched_stamp = sched_tick;
	new_thread->pri_shift = sched_pri_shift;
#endif
	SCHED(compute_priority)(new_thread, FALSE);

	new_thread->active = TRUE;

	*out_thread = new_thread;

	{
		long	dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4;

		kdbg_trace_data(parent_task->bsd_info, &dbg_arg2);

		KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, 
			TRACEDBG_CODE(DBG_TRACE_DATA, 1) | DBG_FUNC_NONE,
			(vm_address_t)(uintptr_t)thread_tid(new_thread), dbg_arg2, 0, 0, 0);

		kdbg_trace_string(parent_task->bsd_info,
							&dbg_arg1, &dbg_arg2, &dbg_arg3, &dbg_arg4);

		KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, 
			TRACEDBG_CODE(DBG_TRACE_STRING, 1) | DBG_FUNC_NONE,
			dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4, 0);
	}

	DTRACE_PROC1(lwp__create, thread_t, *out_thread);

	return (KERN_SUCCESS);
}
Esempio n. 2
0
/*
 *	thread_terminate_self:
 */
void
thread_terminate_self(void)
{
	thread_t		thread = current_thread();

	task_t			task;
	spl_t			s;
	int threadcnt;

	DTRACE_PROC(lwp__exit);

	thread_mtx_lock(thread);

	ulock_release_all(thread);

	ipc_thread_disable(thread);
	
	thread_mtx_unlock(thread);

	s = splsched();
	thread_lock(thread);

	/*
	 *	Cancel priority depression, wait for concurrent expirations
	 *	on other processors.
	 */
	if (thread->sched_flags & TH_SFLAG_DEPRESSED_MASK) {
		thread->sched_flags &= ~TH_SFLAG_DEPRESSED_MASK;

		if (timer_call_cancel(&thread->depress_timer))
			thread->depress_timer_active--;
	}

	while (thread->depress_timer_active > 0) {
		thread_unlock(thread);
		splx(s);

		delay(1);

		s = splsched();
		thread_lock(thread);
	}

	thread_sched_call(thread, NULL);

	thread_unlock(thread);
	splx(s);

	thread_policy_reset(thread);

#if CONFIG_EMBEDDED
	thead_remove_taskwatch(thread);
#endif /* CONFIG_EMBEDDED */

	task = thread->task;
	uthread_cleanup(task, thread->uthread, task->bsd_info);
	threadcnt = hw_atomic_sub(&task->active_thread_count, 1);

	/*
	 * If we are the last thread to terminate and the task is
	 * associated with a BSD process, perform BSD process exit.
	 */
	if (threadcnt == 0 && task->bsd_info != NULL)
		proc_exit(task->bsd_info);

	uthread_cred_free(thread->uthread);

	s = splsched();
	thread_lock(thread);

	/*
	 *	Cancel wait timer, and wait for
	 *	concurrent expirations.
	 */
	if (thread->wait_timer_is_set) {
		thread->wait_timer_is_set = FALSE;

		if (timer_call_cancel(&thread->wait_timer))
			thread->wait_timer_active--;
	}

	while (thread->wait_timer_active > 0) {
		thread_unlock(thread);
		splx(s);

		delay(1);

		s = splsched();
		thread_lock(thread);
	}

	/*
	 *	If there is a reserved stack, release it.
	 */
	if (thread->reserved_stack != 0) {
		stack_free_reserved(thread);
		thread->reserved_stack = 0;
	}

	/*
	 *	Mark thread as terminating, and block.
	 */
	thread->state |= TH_TERMINATE;
	thread_mark_wait_locked(thread, THREAD_UNINT);
	thread_unlock(thread);
	/* splsched */

	thread_block((thread_continue_t)thread_terminate_continue);
	/*NOTREACHED*/
}
Esempio n. 3
0
/*
 * Create a new thread.
 * Doesn't start the thread running.
 */
static kern_return_t
thread_create_internal(
	task_t					parent_task,
	integer_t				priority,
	thread_continue_t		continuation,
	thread_t				*out_thread)
{
	thread_t				new_thread;
	static thread_t			first_thread;

	/*
	 *	Allocate a thread and initialize static fields
	 */
	if (first_thread == NULL)
		new_thread = first_thread = current_thread();
	else
		new_thread = (thread_t)zalloc(thread_zone);
	if (new_thread == NULL)
		return (KERN_RESOURCE_SHORTAGE);

	if (new_thread != first_thread)
		*new_thread = thread_template;

#ifdef MACH_BSD
    {
		new_thread->uthread = uthread_alloc(parent_task, new_thread);
		if (new_thread->uthread == NULL) {
			zfree(thread_zone, new_thread);
			return (KERN_RESOURCE_SHORTAGE);
		}
	}
#endif  /* MACH_BSD */

	if (machine_thread_create(new_thread, parent_task) != KERN_SUCCESS) {
#ifdef MACH_BSD
		{
			void *ut = new_thread->uthread;

			new_thread->uthread = NULL;
			/* cred free may not be necessary */
			uthread_cleanup(parent_task, ut, parent_task->bsd_info);
			uthread_cred_free(ut);
			uthread_zone_free(ut);
		}
#endif  /* MACH_BSD */
		zfree(thread_zone, new_thread);
		return (KERN_FAILURE);
	}

    new_thread->task = parent_task;

	thread_lock_init(new_thread);
	wake_lock_init(new_thread);

	mutex_init(&new_thread->mutex, 0);

	ipc_thread_init(new_thread);
	queue_init(&new_thread->held_ulocks);

	new_thread->continuation = continuation;

	mutex_lock(&tasks_threads_lock);
	task_lock(parent_task);

	if (	!parent_task->active							||
			(parent_task->thread_count >= THREAD_MAX	&&
			 parent_task != kernel_task)) {
		task_unlock(parent_task);
		mutex_unlock(&tasks_threads_lock);

#ifdef MACH_BSD
		{
			void *ut = new_thread->uthread;

			new_thread->uthread = NULL;
			uthread_cleanup(parent_task, ut, parent_task->bsd_info);
			/* cred free may not be necessary */
			uthread_cred_free(ut);
			uthread_zone_free(ut);
		}
#endif  /* MACH_BSD */
		ipc_thread_disable(new_thread);
		ipc_thread_terminate(new_thread);
		machine_thread_destroy(new_thread);
		zfree(thread_zone, new_thread);
		return (KERN_FAILURE);
	}

	task_reference_internal(parent_task);

	/* Cache the task's map */
	new_thread->map = parent_task->map;

	/* Chain the thread onto the task's list */
	queue_enter(&parent_task->threads, new_thread, thread_t, task_threads);
	parent_task->thread_count++;
	
	/* So terminating threads don't need to take the task lock to decrement */
	hw_atomic_add(&parent_task->active_thread_count, 1);

	queue_enter(&threads, new_thread, thread_t, threads);
	threads_count++;

	timer_call_setup(&new_thread->wait_timer, thread_timer_expire, new_thread);
	timer_call_setup(&new_thread->depress_timer, thread_depress_expire, new_thread);

	/* Set the thread's scheduling parameters */
	if (parent_task != kernel_task)
		new_thread->sched_mode |= TH_MODE_TIMESHARE;
	new_thread->max_priority = parent_task->max_priority;
	new_thread->task_priority = parent_task->priority;
	new_thread->priority = (priority < 0)? parent_task->priority: priority;
	if (new_thread->priority > new_thread->max_priority)
		new_thread->priority = new_thread->max_priority;
	new_thread->importance =
					new_thread->priority - new_thread->task_priority;
	new_thread->sched_stamp = sched_tick;
	new_thread->pri_shift = sched_pri_shift;
	compute_priority(new_thread, FALSE);

	new_thread->active = TRUE;

	*out_thread = new_thread;

	{
		long	dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4;

		kdbg_trace_data(parent_task->bsd_info, &dbg_arg2);

		KERNEL_DEBUG_CONSTANT(
					TRACEDBG_CODE(DBG_TRACE_DATA, 1) | DBG_FUNC_NONE,
							(vm_address_t)new_thread, dbg_arg2, 0, 0, 0);

		kdbg_trace_string(parent_task->bsd_info,
							&dbg_arg1, &dbg_arg2, &dbg_arg3, &dbg_arg4);

		KERNEL_DEBUG_CONSTANT(
					TRACEDBG_CODE(DBG_TRACE_STRING, 1) | DBG_FUNC_NONE,
							dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4, 0);
	}

	DTRACE_PROC1(lwp__create, thread_t, *out_thread);

	return (KERN_SUCCESS);
}
Esempio n. 4
0
/*
 *	thread_terminate_self:
 */
void
thread_terminate_self(void)
{
	thread_t		thread = current_thread();
	task_t			task;
	spl_t			s;
	int lastthread = 0;

	thread_mtx_lock(thread);

	ulock_release_all(thread);

	ipc_thread_disable(thread);
	
	thread_mtx_unlock(thread);

	s = splsched();
	thread_lock(thread);

	/*
	 *	Cancel priority depression, wait for concurrent expirations
	 *	on other processors.
	 */
	if (thread->sched_mode & TH_MODE_ISDEPRESSED) {
		thread->sched_mode &= ~TH_MODE_ISDEPRESSED;

		if (timer_call_cancel(&thread->depress_timer))
			thread->depress_timer_active--;
	}

	while (thread->depress_timer_active > 0) {
		thread_unlock(thread);
		splx(s);

		delay(1);

		s = splsched();
		thread_lock(thread);
	}

	thread_unlock(thread);
	splx(s);

	thread_policy_reset(thread);

	/*
	 * If we are the last thread to terminate and the task is
	 * associated with a BSD process, perform BSD process exit.
	 */
	task = thread->task;
	uthread_cleanup(task, thread->uthread, task->bsd_info);
	if (hw_atomic_sub(&task->active_thread_count, 1) == 0	&&
					task->bsd_info != NULL) {
		lastthread = 1;
	} 
	
	if (lastthread != 0)
		proc_exit(task->bsd_info);

	uthread_cred_free(thread->uthread);

	s = splsched();
	thread_lock(thread);

	/*
	 *	Cancel wait timer, and wait for
	 *	concurrent expirations.
	 */
	if (thread->wait_timer_is_set) {
		thread->wait_timer_is_set = FALSE;

		if (timer_call_cancel(&thread->wait_timer))
			thread->wait_timer_active--;
	}

	while (thread->wait_timer_active > 0) {
		thread_unlock(thread);
		splx(s);

		delay(1);

		s = splsched();
		thread_lock(thread);
	}

	/*
	 *	If there is a reserved stack, release it.
	 */
	if (thread->reserved_stack != 0) {
		if (thread->reserved_stack != thread->kernel_stack)
			stack_free_stack(thread->reserved_stack);
		thread->reserved_stack = 0;
	}

	/*
	 *	Mark thread as terminating, and block.
	 */
	thread->state |= TH_TERMINATE;
	thread_mark_wait_locked(thread, THREAD_UNINT);
	assert(thread->promotions == 0);
	thread_unlock(thread);
	/* splsched */

	thread_block((thread_continue_t)thread_terminate_continue);
	/*NOTREACHED*/
}
Esempio n. 5
0
/* to trick uthread_create() */
int main(int argc, char** argv)
{
	uint32_t vcoreid;
	int retval;

	/* Initialize our barrier. */
	mcs_barrier_init(&b, max_vcores());

	/* vcore_context test */
	assert(!in_vcore_context());
	
	/* prep indirect ev_q.  Note we grab a big one */
	indirect_q = get_eventq(EV_MBOX_UCQ);
	indirect_q->ev_flags = EVENT_IPI;
	indirect_q->ev_vcore = 1;			/* IPI core 1 */
	indirect_q->ev_handler = 0;
	printf("Registering %08p for event type %d\n", indirect_q,
	       EV_FREE_APPLE_PIE);
	register_kevent_q(indirect_q, EV_FREE_APPLE_PIE);

	/* handle events: just want to print out what we get.  This is just a
	 * quick set of handlers, not a registration for a kevent. */
	for (int i = 0; i < MAX_NR_EVENT; i++)
		register_ev_handler(i, handle_generic, 0);
	/* Want to use the default ev_ev (which we just overwrote) */
	register_ev_handler(EV_EVENT, handle_ev_ev, 0);
	/* vcore_lib_init() done in vcore_request() now. */
	/* Set up event reception.  For example, this will allow us to receive an
	 * event and IPI for USER_IPIs on vcore 0.  Check event.c for more stuff.
	 * Note you don't have to register for USER_IPIs to receive ones you send
	 * yourself with sys_self_notify(). */
	enable_kevent(EV_USER_IPI, 0, EVENT_IPI | EVENT_VCORE_PRIVATE);
	/* Receive pending preemption events.  (though there's no PP handler) */
	struct event_queue *ev_q = get_eventq_vcpd(0, EVENT_VCORE_PRIVATE);
	ev_q->ev_flags = EVENT_IPI | EVENT_VCORE_APPRO;
	register_kevent_q(ev_q, EV_PREEMPT_PENDING);
	/* We also receive preemption events, it is set up in uthread.c */

	/* Inits a thread for us, though we won't use it.  Just a hack to get into
	 * _M mode.  Note this requests one vcore for us */
	struct uthread dummy = {0};
	uthread_2ls_init(&dummy, &ghetto_sched_ops);
	uthread_mcp_init();
	/* Reset the blockon to be the spinner...  This is really shitty.  Any
	 * blocking calls after we become an MCP and before this will fail.  This is
	 * just mhello showing its warts due to trying to work outside uthread.c */
	ros_syscall_blockon = __ros_syscall_spinon;

	if ((vcoreid = vcore_id())) {
		printf("Should never see me! (from vcore %d)\n", vcoreid);
	} else { // core 0
		temp = 0xdeadbeef;
		printf("Hello from vcore %d with temp addr = %p and temp = %p\n",
		       vcoreid, &temp, temp);
		printf("Multi-Goodbye, world, from PID: %d!\n", sys_getpid());
		printf("Requesting %d vcores\n", max_vcores() - 1);
		retval = vcore_request(max_vcores() - 1); /* since we already have 1 */
		//retval = vcore_request(5);
		printf("This is vcore0, right after vcore_request, retval=%d\n", retval);
		/* vcore_context test */
		assert(!in_vcore_context());
	}

	//#if 0
	/* test notifying my vcore2 */
	udelay(5000000);
	printf("Vcore 0 self-notifying vcore 2 with notif 4!\n");
	struct event_msg msg;
	msg.ev_type = 4;
	sys_self_notify(2, 4, &msg, TRUE);
	udelay(5000000);
	printf("Vcore 0 notifying itself with notif 6!\n");
	msg.ev_type = 6;
	sys_notify(sys_getpid(), 6, &msg);
	udelay(1000000);
	//#endif

	/* test loop for restarting a uthread_ctx */
	if (vcoreid == 0) {
		int ctr = 0;
		while(1) {
			printf("Vcore %d Spinning (%d), temp = %08x!\n", vcoreid, ctr++, temp);
			udelay(5000000);
			//exit(0);
		}
	}

	printf("Vcore %d Done!\n", vcoreid);
	//mcs_barrier_wait(&b,vcore_id());

	printf("All Cores Done!\n", vcoreid);
	while(1); // manually kill from the monitor
	/* since everyone should cleanup their uthreads, even if they don't plan on
	 * calling their code or want uthreads in the first place. <3 */
	uthread_cleanup(&dummy);
	return 0;
}
Esempio n. 6
0
/*
 * Create a new thread.
 * Doesn't start the thread running.
 */
static kern_return_t
thread_create_internal(
	task_t					parent_task,
	integer_t				priority,
	thread_continue_t		continuation,
	int						options,
#define TH_OPTION_NONE		0x00
#define TH_OPTION_NOCRED	0x01
#define TH_OPTION_NOSUSP	0x02
	thread_t				*out_thread)
{
	thread_t				new_thread;
	static thread_t			first_thread;

	/*
	 *	Allocate a thread and initialize static fields
	 */
	if (first_thread == THREAD_NULL)
		new_thread = first_thread = current_thread();
	else
		new_thread = (thread_t)zalloc(thread_zone);
	if (new_thread == THREAD_NULL)
		return (KERN_RESOURCE_SHORTAGE);

	if (new_thread != first_thread)
		*new_thread = thread_template;

#ifdef MACH_BSD
	new_thread->uthread = uthread_alloc(parent_task, new_thread, (options & TH_OPTION_NOCRED) != 0);
	if (new_thread->uthread == NULL) {
		zfree(thread_zone, new_thread);
		return (KERN_RESOURCE_SHORTAGE);
	}
#endif  /* MACH_BSD */

	if (machine_thread_create(new_thread, parent_task) != KERN_SUCCESS) {
#ifdef MACH_BSD
		void *ut = new_thread->uthread;

		new_thread->uthread = NULL;
		/* cred free may not be necessary */
		uthread_cleanup(parent_task, ut, parent_task->bsd_info);
		uthread_cred_free(ut);
		uthread_zone_free(ut);
#endif  /* MACH_BSD */

		zfree(thread_zone, new_thread);
		return (KERN_FAILURE);
	}

    new_thread->task = parent_task;

	thread_lock_init(new_thread);
	wake_lock_init(new_thread);

	lck_mtx_init(&new_thread->mutex, &thread_lck_grp, &thread_lck_attr);

	ipc_thread_init(new_thread);
	queue_init(&new_thread->held_ulocks);

	new_thread->continuation = continuation;

	lck_mtx_lock(&tasks_threads_lock);
	task_lock(parent_task);

	if (	!parent_task->active || parent_task->halting ||
			((options & TH_OPTION_NOSUSP) != 0 &&
			 	parent_task->suspend_count > 0)	||
			(parent_task->thread_count >= task_threadmax &&
				parent_task != kernel_task)		) {
		task_unlock(parent_task);
		lck_mtx_unlock(&tasks_threads_lock);

#ifdef MACH_BSD
		{
			void *ut = new_thread->uthread;

			new_thread->uthread = NULL;
			uthread_cleanup(parent_task, ut, parent_task->bsd_info);
			/* cred free may not be necessary */
			uthread_cred_free(ut);
			uthread_zone_free(ut);
		}
#endif  /* MACH_BSD */
		ipc_thread_disable(new_thread);
		ipc_thread_terminate(new_thread);
		lck_mtx_destroy(&new_thread->mutex, &thread_lck_grp);
		machine_thread_destroy(new_thread);
		zfree(thread_zone, new_thread);
		return (KERN_FAILURE);
	}

	/* New threads inherit any default state on the task */
	machine_thread_inherit_taskwide(new_thread, parent_task);

	task_reference_internal(parent_task);

	/* Cache the task's map */
	new_thread->map = parent_task->map;

	/* Chain the thread onto the task's list */
	queue_enter(&parent_task->threads, new_thread, thread_t, task_threads);
	parent_task->thread_count++;
	
	/* So terminating threads don't need to take the task lock to decrement */
	hw_atomic_add(&parent_task->active_thread_count, 1);

	/* Protected by the tasks_threads_lock */
	new_thread->thread_id = ++thread_unique_id;

	queue_enter(&threads, new_thread, thread_t, threads);
	threads_count++;

	timer_call_setup(&new_thread->wait_timer, thread_timer_expire, new_thread);
	timer_call_setup(&new_thread->depress_timer, thread_depress_expire, new_thread);

#if CONFIG_COUNTERS
	/*
	 * If parent task has any reservations, they need to be propagated to this
	 * thread.
	 */
	new_thread->t_chud = (TASK_PMC_FLAG == (parent_task->t_chud & TASK_PMC_FLAG)) ? 
		THREAD_PMC_FLAG : 0U;
#endif

	/* Set the thread's scheduling parameters */
	if (parent_task != kernel_task)
		new_thread->sched_mode |= TH_MODE_TIMESHARE;
	new_thread->max_priority = parent_task->max_priority;
	new_thread->task_priority = parent_task->priority;
	new_thread->priority = (priority < 0)? parent_task->priority: priority;
	if (new_thread->priority > new_thread->max_priority)
		new_thread->priority = new_thread->max_priority;
	new_thread->importance =
					new_thread->priority - new_thread->task_priority;
	new_thread->sched_stamp = sched_tick;
	new_thread->pri_shift = sched_pri_shift;
	compute_priority(new_thread, FALSE);

	new_thread->active = TRUE;

	*out_thread = new_thread;

	{
		long	dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4;

		kdbg_trace_data(parent_task->bsd_info, &dbg_arg2);

		KERNEL_DEBUG_CONSTANT(
					TRACEDBG_CODE(DBG_TRACE_DATA, 1) | DBG_FUNC_NONE,
							(vm_address_t)(uintptr_t)thread_tid(new_thread), dbg_arg2, 0, 0, 0);

		kdbg_trace_string(parent_task->bsd_info,
							&dbg_arg1, &dbg_arg2, &dbg_arg3, &dbg_arg4);

		KERNEL_DEBUG_CONSTANT(
					TRACEDBG_CODE(DBG_TRACE_STRING, 1) | DBG_FUNC_NONE,
							dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4, 0);
	}

	DTRACE_PROC1(lwp__create, thread_t, *out_thread);

	return (KERN_SUCCESS);
}