processor.c   [plain text]

/*
 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/* 
 * Mach Operating System
 * Copyright (c) 1991,1990,1989,1988 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 */

/*
 *	processor.c: processor and processor_set manipulation routines.
 */

#include <mach/boolean.h>
#include <mach/policy.h>
#include <mach/processor.h>
#include <mach/processor_info.h>
#include <mach/vm_param.h>
#include <kern/cpu_number.h>
#include <kern/host.h>
#include <kern/machine.h>
#include <kern/misc_protos.h>
#include <kern/processor.h>
#include <kern/sched.h>
#include <kern/task.h>
#include <kern/thread.h>
#include <kern/ipc_host.h>
#include <kern/ipc_tt.h>
#include <ipc/ipc_port.h>
#include <kern/kalloc.h>

/*
 * Exported interface
 */
#include <mach/mach_host_server.h>
#include <mach/processor_set_server.h>

/*
 *	Exported variables.
 */
struct processor_set	default_pset;

processor_t				processor_list;
unsigned int			processor_count;
static processor_t		processor_list_tail;
decl_simple_lock_data(,processor_list_lock)

processor_t	master_processor;
int 		master_cpu = 0;

/* Forwards */
kern_return_t	processor_set_base(
		processor_set_t 	pset,
		policy_t             	policy,
	        policy_base_t           base,
		boolean_t       	change);

kern_return_t	processor_set_limit(
		processor_set_t 	pset,
		policy_t		policy,
	        policy_limit_t    	limit,
		boolean_t       	change);

kern_return_t	processor_set_things(
		processor_set_t		pset,
		mach_port_t		**thing_list,
		mach_msg_type_number_t	*count,
		int			type);

void
processor_bootstrap(void)
{
	simple_lock_init(&processor_list_lock, 0);

	master_processor = cpu_to_processor(master_cpu);

	processor_init(master_processor, master_cpu);
}

/*
 *	Initialize the given processor_set structure.
 */

void
pset_init(
	register processor_set_t	pset)
{
	register int	i;

	/* setup run queue */
	pset->runq.highq = IDLEPRI;
	for (i = 0; i < NRQBM; i++)
	    pset->runq.bitmap[i] = 0;
	setbit(MAXPRI - IDLEPRI, pset->runq.bitmap); 
	pset->runq.urgency = pset->runq.count = 0;
	for (i = 0; i < NRQS; i++)
	    queue_init(&pset->runq.queues[i]);

	queue_init(&pset->idle_queue);
	pset->idle_count = 0;
	queue_init(&pset->active_queue);
	simple_lock_init(&pset->sched_lock, 0);
	pset->run_count = pset->share_count = 0;
	pset->mach_factor = pset->load_average = 0;
	pset->pri_shift = INT8_MAX;
	queue_init(&pset->processors);
	pset->processor_count = 0;
	queue_init(&pset->tasks);
	pset->task_count = 0;
	queue_init(&pset->threads);
	pset->thread_count = 0;
	pset->ref_count = 1;
	pset->active = TRUE;
	mutex_init(&pset->lock, 0);
	pset->pset_self = IP_NULL;
	pset->pset_name_self = IP_NULL;
	pset->timeshare_quanta = 1;
}

/*
 *	Initialize the given processor structure for the processor in
 *	the slot specified by slot_num.
 */
void
processor_init(
	register processor_t	p,
	int						slot_num)
{
	register int	i;

	/* setup run queue */
	p->runq.highq = IDLEPRI;
	for (i = 0; i < NRQBM; i++)
	    p->runq.bitmap[i] = 0;
	setbit(MAXPRI - IDLEPRI, p->runq.bitmap); 
	p->runq.urgency = p->runq.count = 0;
	for (i = 0; i < NRQS; i++)
	    queue_init(&p->runq.queues[i]);

	p->state = PROCESSOR_OFF_LINE;
	p->active_thread = p->next_thread = p->idle_thread = THREAD_NULL;
	p->processor_set = PROCESSOR_SET_NULL;
	p->current_pri = MINPRI;
	p->deadline = UINT64_MAX;
	timer_call_setup(&p->quantum_timer, thread_quantum_expire, p);
	p->timeslice = 0;
	simple_lock_init(&p->lock, 0);
	p->processor_self = IP_NULL;
	processor_data_init(p);
	PROCESSOR_DATA(p, slot_num) = slot_num;

	simple_lock(&processor_list_lock);
	if (processor_list == NULL)
		processor_list = p;
	else
		processor_list_tail->processor_list = p;
	processor_list_tail = p;
	processor_count++;
	p->processor_list = NULL;
	simple_unlock(&processor_list_lock);
}

/*
 *	pset_deallocate:
 *
 *	Remove one reference to the processor set.  Destroy processor_set
 *	if this was the last reference.
 */
void
pset_deallocate(
	processor_set_t	pset)
{
	if (pset == PROCESSOR_SET_NULL)
		return;

	assert(pset == &default_pset);
	return;
}

/*
 *	pset_reference:
 *
 *	Add one reference to the processor set.
 */
void
pset_reference(
	processor_set_t	pset)
{
	if (pset == PROCESSOR_SET_NULL)
  		return;

	assert(pset == &default_pset);
}

#define pset_reference_locked(pset) assert(pset == &default_pset)

/*
 *	pset_remove_processor() removes a processor from a processor_set.
 *	It can only be called on the current processor.  Caller must
 *	hold lock on current processor and processor set.
 */
void
pset_remove_processor(
	processor_set_t	pset,
	processor_t	processor)
{
	if (pset != processor->processor_set)
		panic("pset_remove_processor: wrong pset");

	queue_remove(&pset->processors, processor, processor_t, processors);
	processor->processor_set = PROCESSOR_SET_NULL;
	pset->processor_count--;
	timeshare_quanta_update(pset);
}

/*
 *	pset_add_processor() adds a  processor to a processor_set.
 *	It can only be called on the current processor.  Caller must
 *	hold lock on curent processor and on pset.  No reference counting on
 *	processors.  Processor reference to pset is implicit.
 */
void
pset_add_processor(
	processor_set_t	pset,
	processor_t	processor)
{
	queue_enter(&pset->processors, processor, processor_t, processors);
	processor->processor_set = pset;
	pset->processor_count++;
	timeshare_quanta_update(pset);
}

/*
 *	pset_remove_task() removes a task from a processor_set.
 *	Caller must hold locks on pset and task (unless task has
 *	no references left, in which case just the pset lock is
 *	needed).  Pset reference count is not decremented;
 *	caller must explicitly pset_deallocate.
 */
void
pset_remove_task(
	processor_set_t	pset,
	task_t		task)
{
	if (pset != task->processor_set)
		return;

	queue_remove(&pset->tasks, task, task_t, pset_tasks);
	pset->task_count--;
}

/*
 *	pset_add_task() adds a  task to a processor_set.
 *	Caller must hold locks on pset and task.  Pset references to
 *	tasks are implicit.
 */
void
pset_add_task(
	processor_set_t	pset,
	task_t		task)
{
	queue_enter(&pset->tasks, task, task_t, pset_tasks);
	task->processor_set = pset;
	pset->task_count++;
	pset_reference_locked(pset);
}

/*
 *	pset_remove_thread() removes a thread from a processor_set.
 *	Caller must hold locks on pset and thread (but only if thread
 *  has outstanding references that could be used to lookup the pset).
 *  The pset reference count is not decremented; caller must explicitly
 *  pset_deallocate.
 */
void
pset_remove_thread(
	processor_set_t	pset,
	thread_t	thread)
{
	queue_remove(&pset->threads, thread, thread_t, pset_threads);
	pset->thread_count--;
}

/*
 *	pset_add_thread() adds a  thread to a processor_set.
 *	Caller must hold locks on pset and thread.  Pset references to
 *	threads are implicit.
 */
void
pset_add_thread(
	processor_set_t	pset,
	thread_t	thread)
{
	queue_enter(&pset->threads, thread, thread_t, pset_threads);
	thread->processor_set = pset;
	pset->thread_count++;
	pset_reference_locked(pset);
}

/*
 *	thread_change_psets() changes the pset of a thread.  Caller must
 *	hold locks on both psets and thread.  The old pset must be
 *	explicitly pset_deallocat()'ed by caller.
 */
void
thread_change_psets(
	thread_t	thread,
	processor_set_t old_pset,
	processor_set_t new_pset)
{
	queue_remove(&old_pset->threads, thread, thread_t, pset_threads);
	old_pset->thread_count--;
	queue_enter(&new_pset->threads, thread, thread_t, pset_threads);
	thread->processor_set = new_pset;
	new_pset->thread_count++;
	pset_reference_locked(new_pset);
}	


kern_return_t
processor_info_count(
	processor_flavor_t		flavor,
	mach_msg_type_number_t	*count)
{
	switch (flavor) {

	case PROCESSOR_BASIC_INFO:
		*count = PROCESSOR_BASIC_INFO_COUNT;
		break;

	case PROCESSOR_CPU_LOAD_INFO:
		*count = PROCESSOR_CPU_LOAD_INFO_COUNT;
		break;

	default:
		return (cpu_info_count(flavor, count));
	}

	return (KERN_SUCCESS);
}


kern_return_t
processor_info(
	register processor_t	processor,
	processor_flavor_t		flavor,
	host_t					*host,
	processor_info_t		info,
	mach_msg_type_number_t	*count)
{
	register int	i, slot_num, state;
	kern_return_t	result;

	if (processor == PROCESSOR_NULL)
		return (KERN_INVALID_ARGUMENT);

	slot_num = PROCESSOR_DATA(processor, slot_num);

	switch (flavor) {

	case PROCESSOR_BASIC_INFO:
	{
		register processor_basic_info_t		basic_info;

		if (*count < PROCESSOR_BASIC_INFO_COUNT)
			return (KERN_FAILURE);

		basic_info = (processor_basic_info_t) info;
		basic_info->cpu_type = slot_type(slot_num);
		basic_info->cpu_subtype = slot_subtype(slot_num);
		state = processor->state;
		if (state == PROCESSOR_OFF_LINE)
			basic_info->running = FALSE;
		else
			basic_info->running = TRUE;
		basic_info->slot_num = slot_num;
		if (processor == master_processor) 
			basic_info->is_master = TRUE;
		else
			basic_info->is_master = FALSE;

		*count = PROCESSOR_BASIC_INFO_COUNT;
		*host = &realhost;

	    return (KERN_SUCCESS);
	}

	case PROCESSOR_CPU_LOAD_INFO:
	{
		register processor_cpu_load_info_t	cpu_load_info;
		register integer_t					*cpu_ticks;

	    if (*count < PROCESSOR_CPU_LOAD_INFO_COUNT)
			return (KERN_FAILURE);

	    cpu_load_info = (processor_cpu_load_info_t) info;
		cpu_ticks = PROCESSOR_DATA(processor, cpu_ticks);
	    for (i=0; i < CPU_STATE_MAX; i++)
			cpu_load_info->cpu_ticks[i] = cpu_ticks[i];

	    *count = PROCESSOR_CPU_LOAD_INFO_COUNT;
	    *host = &realhost;

	    return (KERN_SUCCESS);
	}

	default:
	    result = cpu_info(flavor, slot_num, info, count);
	    if (result == KERN_SUCCESS)
			*host = &realhost;		   

	    return (result);
	}
}

kern_return_t
processor_start(
	processor_t	processor)
{
	kern_return_t	result;
	thread_t		thread;   
	spl_t			s;

	if (processor == PROCESSOR_NULL)
		return (KERN_INVALID_ARGUMENT);

	if (processor == master_processor) {
		thread_t		self = current_thread();
		processor_t		prev;

		prev = thread_bind(self, processor);
		thread_block(THREAD_CONTINUE_NULL);

		result = cpu_start(PROCESSOR_DATA(processor, slot_num));

		thread_bind(self, prev);

		return (result);
	}

	s = splsched();
	processor_lock(processor);
	if (processor->state != PROCESSOR_OFF_LINE) {
		processor_unlock(processor);
		splx(s);

		return (KERN_FAILURE);
	}

	processor->state = PROCESSOR_START;
	processor_unlock(processor);
	splx(s);

	/*
	 *	Create the idle processor thread.
	 */
	if (processor->idle_thread == THREAD_NULL) {
		result = idle_thread_create(processor);
		if (result != KERN_SUCCESS) {
			s = splsched();
			processor_lock(processor);
			processor->state = PROCESSOR_OFF_LINE;
			processor_unlock(processor);
			splx(s);

			return (result);
		}
	}

	/*
	 *	If there is no active thread, the processor
	 *	has never been started.  Create a dedicated
	 *	start up thread.
	 */
	if (	processor->active_thread == THREAD_NULL		&&
			processor->next_thread == THREAD_NULL		) {
		result = kernel_thread_create((thread_continue_t)processor_start_thread, NULL, MAXPRI_KERNEL, &thread);
		if (result != KERN_SUCCESS) {
			s = splsched();
			processor_lock(processor);
			processor->state = PROCESSOR_OFF_LINE;
			processor_unlock(processor);
			splx(s);

			return (result);
		}

		s = splsched();
		thread_lock(thread);
		thread->bound_processor = processor;
		processor->next_thread = thread;
		thread->state = TH_RUN;
		thread_unlock(thread);
		splx(s);

		thread_deallocate(thread);
	}

	if (processor->processor_self == IP_NULL)
		ipc_processor_init(processor);

	result = cpu_start(PROCESSOR_DATA(processor, slot_num));
	if (result != KERN_SUCCESS) {
		s = splsched();
		processor_lock(processor);
		processor->state = PROCESSOR_OFF_LINE;
		timer_call_shutdown(processor);
		processor_unlock(processor);
		splx(s);

		return (result);
	}

	ipc_processor_enable(processor);

	return (KERN_SUCCESS);
}

kern_return_t
processor_exit(
	processor_t	processor)
{
	if (processor == PROCESSOR_NULL)
		return(KERN_INVALID_ARGUMENT);

	return(processor_shutdown(processor));
}

kern_return_t
processor_control(
	processor_t		processor,
	processor_info_t	info,
	mach_msg_type_number_t	count)
{
	if (processor == PROCESSOR_NULL)
		return(KERN_INVALID_ARGUMENT);

	return(cpu_control(PROCESSOR_DATA(processor, slot_num), info, count));
}

/*
 *	Calculate the appropriate timesharing quanta based on set load.
 */

void
timeshare_quanta_update(
	processor_set_t		pset)
{
	int		pcount = pset->processor_count;
	int		i = pset->runq.count;

	if (i >= pcount)
		i = 1;
	else
	if (i <= 1)
		i = pcount;
	else
		i = (pcount + (i / 2)) / i;

	pset->timeshare_quanta = i;
}
	    
kern_return_t
processor_set_create(
	__unused host_t		host,
	__unused processor_set_t	*new_set,
	__unused processor_set_t	*new_name)
{
	return(KERN_FAILURE);
}

kern_return_t
processor_set_destroy(
	__unused processor_set_t	pset)
{
	return(KERN_FAILURE);
}

kern_return_t
processor_get_assignment(
	processor_t	processor,
	processor_set_t	*pset)
{
    	int state;

	state = processor->state;
	if (state == PROCESSOR_SHUTDOWN || state == PROCESSOR_OFF_LINE)
		return(KERN_FAILURE);

	*pset = processor->processor_set;
	pset_reference(*pset);
	return(KERN_SUCCESS);
}

kern_return_t
processor_set_info(
	processor_set_t		pset,
	int			flavor,
	host_t			*host,
	processor_set_info_t	info,
	mach_msg_type_number_t	*count)
{
	if (pset == PROCESSOR_SET_NULL)
		return(KERN_INVALID_ARGUMENT);

	if (flavor == PROCESSOR_SET_BASIC_INFO) {
		register processor_set_basic_info_t	basic_info;

		if (*count < PROCESSOR_SET_BASIC_INFO_COUNT)
			return(KERN_FAILURE);

		basic_info = (processor_set_basic_info_t) info;
		basic_info->processor_count = pset->processor_count;
		basic_info->default_policy = POLICY_TIMESHARE;

		*count = PROCESSOR_SET_BASIC_INFO_COUNT;
		*host = &realhost;
		return(KERN_SUCCESS);
	}
	else if (flavor == PROCESSOR_SET_TIMESHARE_DEFAULT) {
		register policy_timeshare_base_t	ts_base;

		if (*count < POLICY_TIMESHARE_BASE_COUNT)
			return(KERN_FAILURE);

		ts_base = (policy_timeshare_base_t) info;
		ts_base->base_priority = BASEPRI_DEFAULT;

		*count = POLICY_TIMESHARE_BASE_COUNT;
		*host = &realhost;
		return(KERN_SUCCESS);
	}
	else if (flavor == PROCESSOR_SET_FIFO_DEFAULT) {
		register policy_fifo_base_t		fifo_base;

		if (*count < POLICY_FIFO_BASE_COUNT)
			return(KERN_FAILURE);

		fifo_base = (policy_fifo_base_t) info;
		fifo_base->base_priority = BASEPRI_DEFAULT;

		*count = POLICY_FIFO_BASE_COUNT;
		*host = &realhost;
		return(KERN_SUCCESS);
	}
	else if (flavor == PROCESSOR_SET_RR_DEFAULT) {
		register policy_rr_base_t		rr_base;

		if (*count < POLICY_RR_BASE_COUNT)
			return(KERN_FAILURE);

		rr_base = (policy_rr_base_t) info;
		rr_base->base_priority = BASEPRI_DEFAULT;
		rr_base->quantum = 1;

		*count = POLICY_RR_BASE_COUNT;
		*host = &realhost;
		return(KERN_SUCCESS);
	}
	else if (flavor == PROCESSOR_SET_TIMESHARE_LIMITS) {
		register policy_timeshare_limit_t	ts_limit;

		if (*count < POLICY_TIMESHARE_LIMIT_COUNT)
			return(KERN_FAILURE);

		ts_limit = (policy_timeshare_limit_t) info;
		ts_limit->max_priority = MAXPRI_KERNEL;

		*count = POLICY_TIMESHARE_LIMIT_COUNT;
		*host = &realhost;
		return(KERN_SUCCESS);
	}
	else if (flavor == PROCESSOR_SET_FIFO_LIMITS) {
		register policy_fifo_limit_t		fifo_limit;

		if (*count < POLICY_FIFO_LIMIT_COUNT)
			return(KERN_FAILURE);

		fifo_limit = (policy_fifo_limit_t) info;
		fifo_limit->max_priority = MAXPRI_KERNEL;

		*count = POLICY_FIFO_LIMIT_COUNT;
		*host = &realhost;
		return(KERN_SUCCESS);
	}
	else if (flavor == PROCESSOR_SET_RR_LIMITS) {
		register policy_rr_limit_t		rr_limit;

		if (*count < POLICY_RR_LIMIT_COUNT)
			return(KERN_FAILURE);

		rr_limit = (policy_rr_limit_t) info;
		rr_limit->max_priority = MAXPRI_KERNEL;

		*count = POLICY_RR_LIMIT_COUNT;
		*host = &realhost;
		return(KERN_SUCCESS);
	}
	else if (flavor == PROCESSOR_SET_ENABLED_POLICIES) {
		register int				*enabled;

		if (*count < (sizeof(*enabled)/sizeof(int)))
			return(KERN_FAILURE);

		enabled = (int *) info;
		*enabled = POLICY_TIMESHARE | POLICY_RR | POLICY_FIFO;

		*count = sizeof(*enabled)/sizeof(int);
		*host = &realhost;
		return(KERN_SUCCESS);
	}


	*host = HOST_NULL;
	return(KERN_INVALID_ARGUMENT);
}

/*
 *	processor_set_statistics
 *
 *	Returns scheduling statistics for a processor set. 
 */
kern_return_t 
processor_set_statistics(
	processor_set_t         pset,
	int                     flavor,
	processor_set_info_t    info,
	mach_msg_type_number_t	*count)
{
        if (pset == PROCESSOR_SET_NULL)
                return (KERN_INVALID_PROCESSOR_SET);

        if (flavor == PROCESSOR_SET_LOAD_INFO) {
                register processor_set_load_info_t     load_info;

                if (*count < PROCESSOR_SET_LOAD_INFO_COUNT)
                        return(KERN_FAILURE);

                load_info = (processor_set_load_info_t) info;

                pset_lock(pset);
                load_info->task_count = pset->task_count;
                load_info->thread_count = pset->thread_count;
                load_info->mach_factor = pset->mach_factor;
                load_info->load_average = pset->load_average;
                pset_unlock(pset);

                *count = PROCESSOR_SET_LOAD_INFO_COUNT;
                return(KERN_SUCCESS);
        }

        return(KERN_INVALID_ARGUMENT);
}

/*
 *	processor_set_max_priority:
 *
 *	Specify max priority permitted on processor set.  This affects
 *	newly created and assigned threads.  Optionally change existing
 * 	ones.
 */
kern_return_t
processor_set_max_priority(
	__unused processor_set_t	pset,
	__unused int			max_priority,
	__unused boolean_t		change_threads)
{
	return (KERN_INVALID_ARGUMENT);
}

/*
 *	processor_set_policy_enable:
 *
 *	Allow indicated policy on processor set.
 */

kern_return_t
processor_set_policy_enable(
	__unused processor_set_t	pset,
	__unused int			policy)
{
	return (KERN_INVALID_ARGUMENT);
}

/*
 *	processor_set_policy_disable:
 *
 *	Forbid indicated policy on processor set.  Time sharing cannot
 *	be forbidden.
 */
kern_return_t
processor_set_policy_disable(
	__unused processor_set_t	pset,
	__unused int			policy,
	__unused boolean_t		change_threads)
{
	return (KERN_INVALID_ARGUMENT);
}

#define THING_TASK	0
#define THING_THREAD	1

/*
 *	processor_set_things:
 *
 *	Common internals for processor_set_{threads,tasks}
 */
kern_return_t
processor_set_things(
	processor_set_t			pset,
	mach_port_t				**thing_list,
	mach_msg_type_number_t	*count,
	int						type)
{
	unsigned int actual;	/* this many things */
	unsigned int maxthings;
	unsigned int i;

	vm_size_t size, size_needed;
	void  *addr;

	if (pset == PROCESSOR_SET_NULL)
		return (KERN_INVALID_ARGUMENT);

	size = 0; addr = 0;

	for (;;) {
		pset_lock(pset);
		if (!pset->active) {
			pset_unlock(pset);

			return (KERN_FAILURE);
		}

		if (type == THING_TASK)
			maxthings = pset->task_count;
		else
			maxthings = pset->thread_count;

		/* do we have the memory we need? */

		size_needed = maxthings * sizeof (mach_port_t);
		if (size_needed <= size)
			break;

		/* unlock the pset and allocate more memory */
		pset_unlock(pset);

		if (size != 0)
			kfree(addr, size);

		assert(size_needed > 0);
		size = size_needed;

		addr = kalloc(size);
		if (addr == 0)
			return (KERN_RESOURCE_SHORTAGE);
	}

	/* OK, have memory and the processor_set is locked & active */

	actual = 0;
	switch (type) {

	case THING_TASK:
	{
		task_t		task, *tasks = (task_t *)addr;

		for (task = (task_t)queue_first(&pset->tasks);
				!queue_end(&pset->tasks, (queue_entry_t)task);
					task = (task_t)queue_next(&task->pset_tasks)) {
			task_reference_internal(task);
			tasks[actual++] = task;
		}

		break;
	}

	case THING_THREAD:
	{
		thread_t	thread, *threads = (thread_t *)addr;

		for (i = 0, thread = (thread_t)queue_first(&pset->threads);
				!queue_end(&pset->threads, (queue_entry_t)thread);
					thread = (thread_t)queue_next(&thread->pset_threads)) {
			thread_reference_internal(thread);
			threads[actual++] = thread;
		}

		break;
	}
	}
		
	pset_unlock(pset);

	if (actual < maxthings)
		size_needed = actual * sizeof (mach_port_t);

	if (actual == 0) {
		/* no things, so return null pointer and deallocate memory */
		*thing_list = 0;
		*count = 0;

		if (size != 0)
			kfree(addr, size);
	}
	else {
		/* if we allocated too much, must copy */

		if (size_needed < size) {
			void *newaddr;

			newaddr = kalloc(size_needed);
			if (newaddr == 0) {
				switch (type) {

				case THING_TASK:
				{
					task_t		*tasks = (task_t *)addr;

					for (i = 0; i < actual; i++)
						task_deallocate(tasks[i]);
					break;
				}

				case THING_THREAD:
				{
					thread_t	*threads = (thread_t *)addr;

					for (i = 0; i < actual; i++)
						thread_deallocate(threads[i]);
					break;
				}
				}

				kfree(addr, size);
				return (KERN_RESOURCE_SHORTAGE);
			}

			bcopy((void *) addr, (void *) newaddr, size_needed);
			kfree(addr, size);
			addr = newaddr;
		}

		*thing_list = (mach_port_t *)addr;
		*count = actual;

		/* do the conversion that Mig should handle */

		switch (type) {

		case THING_TASK:
		{
			task_t		*tasks = (task_t *)addr;

			for (i = 0; i < actual; i++)
				(*thing_list)[i] = convert_task_to_port(tasks[i]);
			break;
		}

		case THING_THREAD:
		{
			thread_t	*threads = (thread_t *)addr;

			for (i = 0; i < actual; i++)
			  	(*thing_list)[i] = convert_thread_to_port(threads[i]);
			break;
		}
		}
	}

	return (KERN_SUCCESS);
}


/*
 *	processor_set_tasks:
 *
 *	List all tasks in the processor set.
 */
kern_return_t
processor_set_tasks(
	processor_set_t		pset,
	task_array_t		*task_list,
	mach_msg_type_number_t	*count)
{
    return(processor_set_things(pset, (mach_port_t **)task_list, count, THING_TASK));
}

/*
 *	processor_set_threads:
 *
 *	List all threads in the processor set.
 */
kern_return_t
processor_set_threads(
	processor_set_t		pset,
	thread_array_t		*thread_list,
	mach_msg_type_number_t	*count)
{
    return(processor_set_things(pset, (mach_port_t **)thread_list, count, THING_THREAD));
}

/*
 *      processor_set_base:
 *
 *      Specify per-policy base priority for a processor set.  Set processor
 *	set default policy to the given policy. This affects newly created
 *      and assigned threads.  Optionally change existing ones.
 */
kern_return_t
processor_set_base(
	__unused processor_set_t 	pset,
	__unused policy_t		policy,
	__unused policy_base_t	base,
	__unused boolean_t       	change)
{
	return (KERN_INVALID_ARGUMENT);
}

/*
 *      processor_set_limit:
 *
 *      Specify per-policy limits for a processor set.  This affects
 *      newly created and assigned threads.  Optionally change existing
 *      ones.
 */
kern_return_t
processor_set_limit(
	__unused processor_set_t 	pset,
	__unused policy_t		policy,
	__unused policy_limit_t    	limit,
	__unused boolean_t       	change)
{
	return (KERN_POLICY_LIMIT);
}

/*
 *	processor_set_policy_control
 *
 *	Controls the scheduling attributes governing the processor set.
 *	Allows control of enabled policies, and per-policy base and limit
 *	priorities.
 */
kern_return_t
processor_set_policy_control(
	__unused processor_set_t		pset,
	__unused int				flavor,
	__unused processor_set_info_t	policy_info,
	__unused mach_msg_type_number_t	count,
	__unused boolean_t			change)
{
	return (KERN_INVALID_ARGUMENT);
}