[apple/xnu.git] / bsd / kern / kern_synch.c

/*
 * Copyright (c) 2000-2016 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The 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, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/* 
 * Mach Operating System
 * Copyright (c) 1987 Carnegie-Mellon University
 * All rights reserved.  The CMU software License Agreement specifies
 * the terms and conditions for use and redistribution.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc_internal.h>
#include <sys/user.h>
#include <sys/file_internal.h>
#include <sys/vnode.h>
#include <sys/kernel.h>

#include <machine/spl.h>

#include <kern/queue.h>
#include <sys/lock.h>
#include <kern/thread.h>
#include <kern/sched_prim.h>
#include <kern/ast.h>

#include <kern/cpu_number.h>
#include <vm/vm_kern.h>

#include <kern/task.h>
#include <mach/time_value.h>
#include <kern/locks.h>
#include <kern/policy_internal.h>

#include <sys/systm.h>			/* for unix_syscall_return() */
#include <libkern/OSAtomic.h>

extern void compute_averunnable(void *);	/* XXX */

__attribute__((noreturn))
static void
_sleep_continue( __unused void *parameter, wait_result_t wresult)
{
	struct proc *p = current_proc();
	thread_t self  = current_thread();
	struct uthread * ut;
	int sig, catch;
	int error = 0;
	int dropmutex, spinmutex;

	ut = get_bsdthread_info(self);
	catch     = ut->uu_pri & PCATCH;
	dropmutex = ut->uu_pri & PDROP;
	spinmutex = ut->uu_pri & PSPIN;

	switch (wresult) {
		case THREAD_TIMED_OUT:
			error = EWOULDBLOCK;
			break;
		case THREAD_AWAKENED:
			/*
			 * Posix implies any signal should be delivered
			 * first, regardless of whether awakened due
			 * to receiving event.
			 */
			if (!catch)
				break;
			/* else fall through */
		case THREAD_INTERRUPTED:
			if (catch) {
				if (thread_should_abort(self)) {
					error = EINTR;
				} else if (SHOULDissignal(p,ut)) {
					if ((sig = CURSIG(p)) != 0) {
						if (p->p_sigacts->ps_sigintr & sigmask(sig))
							error = EINTR;
						else
							error = ERESTART;
					}
					if (thread_should_abort(self)) {
						error = EINTR;
					}
				} else if( (ut->uu_flag & ( UT_CANCELDISABLE | UT_CANCEL | UT_CANCELED)) == UT_CANCEL) {
                                        /* due to thread cancel */
                                        error = EINTR;
                                }
			}  else
				error = EINTR;
			break;
	}

	if (error == EINTR || error == ERESTART)
		act_set_astbsd(self);

	if (ut->uu_mtx && !dropmutex) {
		if (spinmutex)
			lck_mtx_lock_spin(ut->uu_mtx);
		else
			lck_mtx_lock(ut->uu_mtx);
	}
	ut->uu_wchan = NULL;
	ut->uu_wmesg = NULL;

	unix_syscall_return((*ut->uu_continuation)(error));
}

/*
 * Give up the processor till a wakeup occurs
 * on chan, at which time the process
 * enters the scheduling queue at priority pri.
 * The most important effect of pri is that when
 * pri<=PZERO a signal cannot disturb the sleep;
 * if pri>PZERO signals will be processed.
 * If pri&PCATCH is set, signals will cause sleep
 * to return 1, rather than longjmp.
 * Callers of this routine must be prepared for
 * premature return, and check that the reason for
 * sleeping has gone away.
 *
 * if msleep was the entry point, than we have a mutex to deal with
 *
 * The mutex is unlocked before the caller is blocked, and
 * relocked before msleep returns unless the priority includes the PDROP
 * flag... if PDROP is specified, _sleep returns with the mutex unlocked
 * regardless of whether it actually blocked or not.
 */

static int
_sleep(
	caddr_t		chan,
	int		pri,
	const char	*wmsg,
	u_int64_t	abstime,
	int		(*continuation)(int),
        lck_mtx_t	*mtx)
{
	struct proc *p;
	thread_t self = current_thread();
	struct uthread * ut;
	int sig, catch;
	int dropmutex  = pri & PDROP;
	int spinmutex  = pri & PSPIN;
	int wait_result;
	int error = 0;

	ut = get_bsdthread_info(self);

	p = current_proc();
	p->p_priority = pri & PRIMASK;
	/* It can still block in proc_exit() after the teardown. */
	if (p->p_stats != NULL)
		OSIncrementAtomicLong(&p->p_stats->p_ru.ru_nvcsw);
	
	if (pri & PCATCH)
		catch = THREAD_ABORTSAFE;
	else
		catch = THREAD_UNINT;

	/* set wait message & channel */
	ut->uu_wchan = chan;
	ut->uu_wmesg = wmsg ? wmsg : "unknown";

	if (mtx != NULL && chan != NULL && (thread_continue_t)continuation == THREAD_CONTINUE_NULL) {
		int	flags;

		if (dropmutex)
			flags = LCK_SLEEP_UNLOCK;
		else
			flags = LCK_SLEEP_DEFAULT;

		if (spinmutex)
			flags |= LCK_SLEEP_SPIN;

		if (abstime)
			wait_result = lck_mtx_sleep_deadline(mtx, flags, chan, catch, abstime);
		else
			wait_result = lck_mtx_sleep(mtx, flags, chan, catch);
	}
	else {
		if (chan != NULL)
			assert_wait_deadline(chan, catch, abstime);
		if (mtx)
			lck_mtx_unlock(mtx);

		if (catch == THREAD_ABORTSAFE) {
			if (SHOULDissignal(p,ut)) {
				if ((sig = CURSIG(p)) != 0) {
					if (clear_wait(self, THREAD_INTERRUPTED) == KERN_FAILURE)
						goto block;
					if (p->p_sigacts->ps_sigintr & sigmask(sig))
						error = EINTR;
					else
						error = ERESTART;
					if (mtx && !dropmutex) {
						if (spinmutex)
							lck_mtx_lock_spin(mtx);
						else
							lck_mtx_lock(mtx);
					}
					goto out;
				}
			}
			if (thread_should_abort(self)) {
				if (clear_wait(self, THREAD_INTERRUPTED) == KERN_FAILURE)
					goto block;
				error = EINTR;

				if (mtx && !dropmutex) {
					if (spinmutex)
						lck_mtx_lock_spin(mtx);
					else
						lck_mtx_lock(mtx);
				}
				goto out;
			}
		}		


block:
		if ((thread_continue_t)continuation != THREAD_CONTINUE_NULL) {
		        ut->uu_continuation = continuation;
			ut->uu_pri  = pri;
			ut->uu_timo = abstime? 1: 0;
			ut->uu_mtx  = mtx;
			(void) thread_block(_sleep_continue);
			/* NOTREACHED */
		}
		
		wait_result = thread_block(THREAD_CONTINUE_NULL);

		if (mtx && !dropmutex) {
			if (spinmutex)
				lck_mtx_lock_spin(mtx);
			else
				lck_mtx_lock(mtx);
		}
	}

	switch (wait_result) {
		case THREAD_TIMED_OUT:
			error = EWOULDBLOCK;
			break;
		case THREAD_AWAKENED:
		case THREAD_RESTART:
			/*
			 * Posix implies any signal should be delivered
			 * first, regardless of whether awakened due
			 * to receiving event.
			 */
			if (catch != THREAD_ABORTSAFE)
				break;
			/* else fall through */
		case THREAD_INTERRUPTED:
			if (catch == THREAD_ABORTSAFE) {
				if (thread_should_abort(self)) {
					error = EINTR;
				} else if (SHOULDissignal(p, ut)) {
					if ((sig = CURSIG(p)) != 0) {
						if (p->p_sigacts->ps_sigintr & sigmask(sig))
							error = EINTR;
						else
							error = ERESTART;
					}
					if (thread_should_abort(self)) {
						error = EINTR;
					}
				} else if( (ut->uu_flag & ( UT_CANCELDISABLE | UT_CANCEL | UT_CANCELED)) == UT_CANCEL) {
                                        /* due to thread cancel */
                                        error = EINTR;
                                }
			}  else
				error = EINTR;
			break;
	}
out:
	if (error == EINTR || error == ERESTART)
		act_set_astbsd(self);
	ut->uu_wchan = NULL;
	ut->uu_wmesg = NULL;

	return (error);
}

int
sleep(
	void	*chan,
	int		pri)
{
	return _sleep((caddr_t)chan, pri, (char *)NULL, 0, (int (*)(int))0, (lck_mtx_t *)0);
}

int
msleep0(
	void		*chan,
	lck_mtx_t	*mtx,
	int		pri,
	const char	*wmsg,
	int		timo,
	int		(*continuation)(int))
{
	u_int64_t	abstime = 0;

	if (timo)
		clock_interval_to_deadline(timo, NSEC_PER_SEC / hz, &abstime);

	return _sleep((caddr_t)chan, pri, wmsg, abstime, continuation, mtx);
}

int
msleep(
	void		*chan,
	lck_mtx_t	*mtx,
	int		pri,
	const char	*wmsg,
	struct timespec		*ts)
{
	u_int64_t	abstime = 0;

	if (ts && (ts->tv_sec || ts->tv_nsec)) {
		nanoseconds_to_absolutetime((uint64_t)ts->tv_sec * NSEC_PER_SEC + ts->tv_nsec,  &abstime );
		clock_absolutetime_interval_to_deadline( abstime, &abstime );
	}

	return _sleep((caddr_t)chan, pri, wmsg, abstime, (int (*)(int))0, mtx);
}

int
msleep1(
	void		*chan,
	lck_mtx_t	*mtx,
	int		pri,
	const char	*wmsg,
	u_int64_t	abstime)
{
	return _sleep((caddr_t)chan, pri, wmsg, abstime, (int (*)(int))0, mtx);
}

int
tsleep(
	void		*chan,
	int		pri,
	const char	*wmsg,
	int		timo)
{
	u_int64_t	abstime = 0;

	if (timo)
		clock_interval_to_deadline(timo, NSEC_PER_SEC / hz, &abstime);
	return _sleep((caddr_t)chan, pri, wmsg, abstime, (int (*)(int))0, (lck_mtx_t *)0);
}

int
tsleep0(
	void		*chan,
	int		pri,
	const char	*wmsg,
	int		timo,
	int		(*continuation)(int))
{			
	u_int64_t	abstime = 0;

	if (timo)
		clock_interval_to_deadline(timo, NSEC_PER_SEC / hz, &abstime);
	return _sleep((caddr_t)chan, pri, wmsg, abstime, continuation, (lck_mtx_t *)0);
}

int
tsleep1(
	void		*chan,
	int		pri,
	const char	*wmsg,
	u_int64_t	abstime,
	int		(*continuation)(int))
{			
	return _sleep((caddr_t)chan, pri, wmsg, abstime, continuation, (lck_mtx_t *)0);
}

/*
 * Wake up all processes sleeping on chan.
 */
void
wakeup(void *chan)
{
	thread_wakeup((caddr_t)chan);
}

/*
 * Wake up the first process sleeping on chan.
 *
 * Be very sure that the first process is really
 * the right one to wakeup.
 */
void
wakeup_one(caddr_t chan)
{
	thread_wakeup_one((caddr_t)chan);
}

/*
 * Compute the priority of a process when running in user mode.
 * Arrange to reschedule if the resulting priority is better
 * than that of the current process.
 */
void
resetpriority(struct proc *p)
{
	(void)task_importance(p->task, -p->p_nice);
}

struct loadavg averunnable =
	{ {0, 0, 0}, FSCALE };		/* load average, of runnable procs */
/*
 * Constants for averages over 1, 5, and 15 minutes
 * when sampling at 5 second intervals.
 */
static fixpt_t cexp[3] = {
    (fixpt_t)(0.9200444146293232 * FSCALE),    /* exp(-1/12) */
    (fixpt_t)(0.9834714538216174 * FSCALE),    /* exp(-1/60) */
    (fixpt_t)(0.9944598480048967 * FSCALE),    /* exp(-1/180) */
};

void
compute_averunnable(void *arg)
{
	unsigned int		nrun = *(unsigned int *)arg;
	struct loadavg		*avg = &averunnable;
	int		i;

    for (i = 0; i < 3; i++)
        avg->ldavg[i] = (cexp[i] * avg->ldavg[i] +
            nrun * FSCALE * (FSCALE - cexp[i])) >> FSHIFT;
}
Commit	Line	Data
1c79356b	1	/*
39037602	2	* Copyright (c) 2000-2016 Apple Computer, Inc. All rights reserved.
1c79356b	3	*
2d21ac55	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b	5	*
2d21ac55 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
8f6c56a5	14	*
2d21ac55 A	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
8f6c56a5 A	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
8f6c56a5 A	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55 A	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
8f6c56a5	25	*
2d21ac55	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
1c79356b A	27	*/
	28	/*
	29	* Mach Operating System
	30	* Copyright (c) 1987 Carnegie-Mellon University
	31	* All rights reserved. The CMU software License Agreement specifies
	32	* the terms and conditions for use and redistribution.
	33	*/
	34
	35	#include <sys/param.h>
	36	#include <sys/systm.h>
91447636	37	#include <sys/proc_internal.h>
1c79356b	38	#include <sys/user.h>
91447636	39	#include <sys/file_internal.h>
1c79356b A	40	#include <sys/vnode.h>
1c79356b A	41	#include <sys/kernel.h>
1c79356b A	42
	43	#include <machine/spl.h>
	44
	45	#include <kern/queue.h>
	46	#include <sys/lock.h>
	47	#include <kern/thread.h>
9bccf70c	48	#include <kern/sched_prim.h>
1c79356b A	49	#include <kern/ast.h>
	50
	51	#include <kern/cpu_number.h>
	52	#include <vm/vm_kern.h>
	53
	54	#include <kern/task.h>
	55	#include <mach/time_value.h>
fe8ab488	56	#include <kern/locks.h>
39037602	57	#include <kern/policy_internal.h>
91447636	58
2d21ac55 A	59	#include <sys/systm.h> /* for unix_syscall_return() */
	60	#include <libkern/OSAtomic.h>
	61
2d21ac55 A	62	extern void compute_averunnable(void ); / XXX */
2d21ac55 A	63
39037602	64	__attribute__((noreturn))
9bccf70c	65	static void
2d21ac55	66	_sleep_continue( __unused void *parameter, wait_result_t wresult)
1c79356b	67	{
2d21ac55 A	68	struct proc *p = current_proc();
2d21ac55 A	69	thread_t self = current_thread();
1c79356b A	70	struct uthread * ut;
	71	int sig, catch;
	72	int error = 0;
b0d623f7	73	int dropmutex, spinmutex;
1c79356b	74
55e303ae	75	ut = get_bsdthread_info(self);
91447636 A	76	catch = ut->uu_pri & PCATCH;
91447636 A	77	dropmutex = ut->uu_pri & PDROP;
b0d623f7	78	spinmutex = ut->uu_pri & PSPIN;
1c79356b	79
91447636	80	switch (wresult) {
1c79356b A	81	case THREAD_TIMED_OUT:
	82	error = EWOULDBLOCK;
	83	break;
	84	case THREAD_AWAKENED:
	85	/*
	86	* Posix implies any signal should be delivered
	87	* first, regardless of whether awakened due
	88	* to receiving event.
	89	*/
	90	if (!catch)
	91	break;
	92	/* else fall through */
	93	case THREAD_INTERRUPTED:
	94	if (catch) {
55e303ae	95	if (thread_should_abort(self)) {
1c79356b A	96	error = EINTR;
1c79356b A	97	} else if (SHOULDissignal(p,ut)) {
2d21ac55	98	if ((sig = CURSIG(p)) != 0) {
1c79356b A	99	if (p->p_sigacts->ps_sigintr & sigmask(sig))
	100	error = EINTR;
	101	else
	102	error = ERESTART;
	103	}
55e303ae	104	if (thread_should_abort(self)) {
1c79356b A	105	error = EINTR;
1c79356b A	106	}
91447636 A	107	} else if( (ut->uu_flag & ( UT_CANCELDISABLE \| UT_CANCEL \| UT_CANCELED)) == UT_CANCEL) {
	108	/* due to thread cancel */
	109	error = EINTR;
	110	}
1c79356b A	111	} else
	112	error = EINTR;
	113	break;
	114	}
	115
9bccf70c	116	if (error == EINTR \|\| error == ERESTART)
55e303ae	117	act_set_astbsd(self);
9bccf70c	118
b0d623f7 A	119	if (ut->uu_mtx && !dropmutex) {
	120	if (spinmutex)
	121	lck_mtx_lock_spin(ut->uu_mtx);
	122	else
	123	lck_mtx_lock(ut->uu_mtx);
	124	}
2d21ac55 A	125	ut->uu_wchan = NULL;
	126	ut->uu_wmesg = NULL;
	127
1c79356b A	128	unix_syscall_return((*ut->uu_continuation)(error));
	129	}
	130
	131	/*
	132	* Give up the processor till a wakeup occurs
	133	* on chan, at which time the process
	134	* enters the scheduling queue at priority pri.
	135	* The most important effect of pri is that when
	136	* pri<=PZERO a signal cannot disturb the sleep;
	137	* if pri>PZERO signals will be processed.
	138	* If pri&PCATCH is set, signals will cause sleep
	139	* to return 1, rather than longjmp.
	140	* Callers of this routine must be prepared for
	141	* premature return, and check that the reason for
	142	* sleeping has gone away.
91447636 A	143	*
	144	* if msleep was the entry point, than we have a mutex to deal with
	145	*
	146	* The mutex is unlocked before the caller is blocked, and
	147	* relocked before msleep returns unless the priority includes the PDROP
	148	* flag... if PDROP is specified, _sleep returns with the mutex unlocked
	149	* regardless of whether it actually blocked or not.
1c79356b A	150	*/
1c79356b A	151
9bccf70c A	152	static int
	153	_sleep(
	154	caddr_t chan,
91447636 A	155	int pri,
91447636 A	156	const char *wmsg,
9bccf70c	157	u_int64_t abstime,
91447636 A	158	int (*continuation)(int),
91447636 A	159	lck_mtx_t *mtx)
1c79356b	160	{
2d21ac55 A	161	struct proc *p;
2d21ac55 A	162	thread_t self = current_thread();
1c79356b	163	struct uthread * ut;
6d2010ae	164	int sig, catch;
91447636	165	int dropmutex = pri & PDROP;
b0d623f7	166	int spinmutex = pri & PSPIN;
9bccf70c	167	int wait_result;
1c79356b	168	int error = 0;
1c79356b	169
55e303ae	170	ut = get_bsdthread_info(self);
91447636	171
1c79356b	172	p = current_proc();
1c79356b	173	p->p_priority = pri & PRIMASK;
2d21ac55 A	174	/* It can still block in proc_exit() after the teardown. */
2d21ac55 A	175	if (p->p_stats != NULL)
b0d623f7	176	OSIncrementAtomicLong(&p->p_stats->p_ru.ru_nvcsw);
6d2010ae A	177
	178	if (pri & PCATCH)
	179	catch = THREAD_ABORTSAFE;
	180	else
	181	catch = THREAD_UNINT;
2d21ac55 A	182
	183	/* set wait message & channel */
	184	ut->uu_wchan = chan;
	185	ut->uu_wmesg = wmsg ? wmsg : "unknown";
91447636 A	186
91447636 A	187	if (mtx != NULL && chan != NULL && (thread_continue_t)continuation == THREAD_CONTINUE_NULL) {
6d2010ae A	188	int flags;
	189
	190	if (dropmutex)
	191	flags = LCK_SLEEP_UNLOCK;
	192	else
	193	flags = LCK_SLEEP_DEFAULT;
	194
	195	if (spinmutex)
	196	flags \|= LCK_SLEEP_SPIN;
91447636 A	197
91447636 A	198	if (abstime)
6d2010ae	199	wait_result = lck_mtx_sleep_deadline(mtx, flags, chan, catch, abstime);
91447636	200	else
6d2010ae	201	wait_result = lck_mtx_sleep(mtx, flags, chan, catch);
91447636 A	202	}
	203	else {
	204	if (chan != NULL)
6d2010ae	205	assert_wait_deadline(chan, catch, abstime);
91447636 A	206	if (mtx)
91447636 A	207	lck_mtx_unlock(mtx);
6d2010ae A	208
6d2010ae A	209	if (catch == THREAD_ABORTSAFE) {
91447636	210	if (SHOULDissignal(p,ut)) {
2d21ac55	211	if ((sig = CURSIG(p)) != 0) {
91447636 A	212	if (clear_wait(self, THREAD_INTERRUPTED) == KERN_FAILURE)
91447636 A	213	goto block;
91447636 A	214	if (p->p_sigacts->ps_sigintr & sigmask(sig))
	215	error = EINTR;
	216	else
	217	error = ERESTART;
b0d623f7 A	218	if (mtx && !dropmutex) {
	219	if (spinmutex)
	220	lck_mtx_lock_spin(mtx);
	221	else
	222	lck_mtx_lock(mtx);
	223	}
1c79356b A	224	goto out;
1c79356b A	225	}
91447636 A	226	}
	227	if (thread_should_abort(self)) {
	228	if (clear_wait(self, THREAD_INTERRUPTED) == KERN_FAILURE)
	229	goto block;
	230	error = EINTR;
	231
b0d623f7 A	232	if (mtx && !dropmutex) {
	233	if (spinmutex)
	234	lck_mtx_lock_spin(mtx);
	235	else
	236	lck_mtx_lock(mtx);
	237	}
1c79356b A	238	goto out;
1c79356b A	239	}
91447636	240	}
1c79356b	241
55e303ae	242
91447636 A	243	block:
	244	if ((thread_continue_t)continuation != THREAD_CONTINUE_NULL) {
	245	ut->uu_continuation = continuation;
	246	ut->uu_pri = pri;
	247	ut->uu_timo = abstime? 1: 0;
	248	ut->uu_mtx = mtx;
	249	(void) thread_block(_sleep_continue);
	250	/* NOTREACHED */
	251	}
	252
	253	wait_result = thread_block(THREAD_CONTINUE_NULL);
1c79356b	254
b0d623f7 A	255	if (mtx && !dropmutex) {
	256	if (spinmutex)
	257	lck_mtx_lock_spin(mtx);
	258	else
	259	lck_mtx_lock(mtx);
	260	}
1c79356b A	261	}
1c79356b A	262
9bccf70c	263	switch (wait_result) {
1c79356b A	264	case THREAD_TIMED_OUT:
	265	error = EWOULDBLOCK;
	266	break;
	267	case THREAD_AWAKENED:
39037602	268	case THREAD_RESTART:
1c79356b A	269	/*
	270	* Posix implies any signal should be delivered
	271	* first, regardless of whether awakened due
	272	* to receiving event.
	273	*/
6d2010ae	274	if (catch != THREAD_ABORTSAFE)
1c79356b A	275	break;
	276	/* else fall through */
	277	case THREAD_INTERRUPTED:
6d2010ae	278	if (catch == THREAD_ABORTSAFE) {
55e303ae	279	if (thread_should_abort(self)) {
1c79356b	280	error = EINTR;
91447636	281	} else if (SHOULDissignal(p, ut)) {
2d21ac55	282	if ((sig = CURSIG(p)) != 0) {
1c79356b A	283	if (p->p_sigacts->ps_sigintr & sigmask(sig))
	284	error = EINTR;
	285	else
	286	error = ERESTART;
	287	}
55e303ae	288	if (thread_should_abort(self)) {
1c79356b A	289	error = EINTR;
1c79356b A	290	}
b0d623f7 A	291	} else if( (ut->uu_flag & ( UT_CANCELDISABLE \| UT_CANCEL \| UT_CANCELED)) == UT_CANCEL) {
	292	/* due to thread cancel */
	293	error = EINTR;
	294	}
1c79356b A	295	} else
	296	error = EINTR;
	297	break;
	298	}
	299	out:
9bccf70c	300	if (error == EINTR \|\| error == ERESTART)
55e303ae	301	act_set_astbsd(self);
2d21ac55 A	302	ut->uu_wchan = NULL;
2d21ac55 A	303	ut->uu_wmesg = NULL;
91447636	304
1c79356b A	305	return (error);
	306	}
	307
9bccf70c A	308	int
	309	sleep(
	310	void *chan,
	311	int pri)
1c79356b	312	{
91447636 A	313	return _sleep((caddr_t)chan, pri, (char )NULL, 0, (int ()(int))0, (lck_mtx_t *)0);
	314	}
	315
	316	int
	317	msleep0(
	318	void *chan,
	319	lck_mtx_t *mtx,
	320	int pri,
	321	const char *wmsg,
	322	int timo,
	323	int (*continuation)(int))
	324	{
	325	u_int64_t abstime = 0;
	326
	327	if (timo)
	328	clock_interval_to_deadline(timo, NSEC_PER_SEC / hz, &abstime);
	329
	330	return _sleep((caddr_t)chan, pri, wmsg, abstime, continuation, mtx);
	331	}
	332
	333	int
	334	msleep(
	335	void *chan,
	336	lck_mtx_t *mtx,
	337	int pri,
	338	const char *wmsg,
	339	struct timespec *ts)
	340	{
	341	u_int64_t abstime = 0;
	342
	343	if (ts && (ts->tv_sec \|\| ts->tv_nsec)) {
	344	nanoseconds_to_absolutetime((uint64_t)ts->tv_sec * NSEC_PER_SEC + ts->tv_nsec, &abstime );
	345	clock_absolutetime_interval_to_deadline( abstime, &abstime );
	346	}
	347
	348	return _sleep((caddr_t)chan, pri, wmsg, abstime, (int (*)(int))0, mtx);
	349	}
	350
	351	int
	352	msleep1(
	353	void *chan,
	354	lck_mtx_t *mtx,
	355	int pri,
	356	const char *wmsg,
	357	u_int64_t abstime)
	358	{
	359	return _sleep((caddr_t)chan, pri, wmsg, abstime, (int (*)(int))0, mtx);
1c79356b A	360	}
1c79356b A	361
9bccf70c A	362	int
9bccf70c A	363	tsleep(
91447636	364	void *chan,
9bccf70c	365	int pri,
91447636	366	const char *wmsg,
9bccf70c A	367	int timo)
	368	{
	369	u_int64_t abstime = 0;
	370
	371	if (timo)
	372	clock_interval_to_deadline(timo, NSEC_PER_SEC / hz, &abstime);
91447636	373	return _sleep((caddr_t)chan, pri, wmsg, abstime, (int ()(int))0, (lck_mtx_t )0);
1c79356b A	374	}
1c79356b A	375
9bccf70c A	376	int
9bccf70c A	377	tsleep0(
91447636	378	void *chan,
9bccf70c	379	int pri,
91447636	380	const char *wmsg,
9bccf70c A	381	int timo,
9bccf70c A	382	int (*continuation)(int))
1c79356b	383	{
9bccf70c A	384	u_int64_t abstime = 0;
	385
	386	if (timo)
	387	clock_interval_to_deadline(timo, NSEC_PER_SEC / hz, &abstime);
91447636	388	return _sleep((caddr_t)chan, pri, wmsg, abstime, continuation, (lck_mtx_t *)0);
0b4e3aa0 A	389	}
0b4e3aa0 A	390
9bccf70c A	391	int
	392	tsleep1(
	393	void *chan,
91447636 A	394	int pri,
91447636 A	395	const char *wmsg,
9bccf70c	396	u_int64_t abstime,
91447636	397	int (*continuation)(int))
0b4e3aa0	398	{
91447636	399	return _sleep((caddr_t)chan, pri, wmsg, abstime, continuation, (lck_mtx_t *)0);
1c79356b A	400	}
	401
	402	/*
	403	* Wake up all processes sleeping on chan.
	404	*/
	405	void
2d21ac55	406	wakeup(void *chan)
1c79356b	407	{
6d2010ae	408	thread_wakeup((caddr_t)chan);
1c79356b A	409	}
	410
	411	/*
	412	* Wake up the first process sleeping on chan.
	413	*
	414	* Be very sure that the first process is really
	415	* the right one to wakeup.
	416	*/
9bccf70c	417	void
2d21ac55	418	wakeup_one(caddr_t chan)
1c79356b	419	{
6d2010ae	420	thread_wakeup_one((caddr_t)chan);
1c79356b A	421	}
	422
	423	/*
	424	* Compute the priority of a process when running in user mode.
	425	* Arrange to reschedule if the resulting priority is better
	426	* than that of the current process.
	427	*/
	428	void
2d21ac55	429	resetpriority(struct proc *p)
1c79356b	430	{
0b4e3aa0	431	(void)task_importance(p->task, -p->p_nice);
1c79356b	432	}
9bccf70c A	433
	434	struct loadavg averunnable =
	435	{ {0, 0, 0}, FSCALE }; /* load average, of runnable procs */
	436	/*
	437	* Constants for averages over 1, 5, and 15 minutes
	438	* when sampling at 5 second intervals.
	439	*/
	440	static fixpt_t cexp[3] = {
	441	(fixpt_t)(0.9200444146293232 * FSCALE), /* exp(-1/12) */
	442	(fixpt_t)(0.9834714538216174 * FSCALE), /* exp(-1/60) */
	443	(fixpt_t)(0.9944598480048967 * FSCALE), /* exp(-1/180) */
	444	};
	445
	446	void
2d21ac55	447	compute_averunnable(void *arg)
9bccf70c	448	{
91447636	449	unsigned int nrun = (unsigned int )arg;
9bccf70c	450	struct loadavg *avg = &averunnable;
2d21ac55	451	int i;
9bccf70c A	452
	453	for (i = 0; i < 3; i++)
	454	avg->ldavg[i] = (cexp[i] * avg->ldavg[i] +
	455	nrun * FSCALE * (FSCALE - cexp[i])) >> FSHIFT;
	456	}