xref: /xnu-12377.1.9/osfmk/kern/timer.c (revision f6217f891ac0bb64f3d375211650a4c1ff8ca1ea)

/*
 * Copyright (c) 2000-2018 Apple Inc. All rights reserved.
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 * @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
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/*
 * @OSF_COPYRIGHT@
 */
/*
 * Mach Operating System
 * Copyright (c) 1991,1990,1989,1988,1987 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  [email protected]
 *  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.
 */

#include <mach/kern_return.h>
#include <mach/port.h>
#include <kern/queue.h>
#include <kern/processor.h>
#include <kern/thread.h>
#include <kern/sched_prim.h>
#include <kern/timer.h>

#include <machine/config.h>

void
timer_init(timer_t timer)
{
	memset(timer, 0, sizeof(*timer));
}

static void
timer_advance(timer_t timer, uint64_t delta)
{
#if defined(__LP64__)
	timer->all_bits += delta;
#else /* defined(__LP64__) */
	extern void timer_advance_internal_32(timer_t timer, uint32_t high,
	    uint32_t low);
	uint64_t low = delta + timer->low_bits;
	if (low >> 32) {
		timer_advance_internal_32(timer,
		    (uint32_t)(timer->high_bits + (low >> 32)), (uint32_t)low);
	} else {
		timer->low_bits = (uint32_t)low;
	}
#endif /* defined(__LP64__) */
}

void
timer_start(timer_t timer, uint64_t tstamp)
{
	timer->tstamp = tstamp;
}

void
timer_stop(timer_t timer, uint64_t tstamp)
{
	timer_advance(timer, tstamp - timer->tstamp);
}

void
timer_update(timer_t timer, uint64_t tstamp)
{
	timer_advance(timer, tstamp - timer->tstamp);
	timer->tstamp = tstamp;
}