xref: /xnu-10002.1.13/osfmk/kern/timer.h (revision 1031c584a5e37aff177559b9f69dbd3c8c3fd30a)
1*1031c584SApple OSS Distributions /*
2*1031c584SApple OSS Distributions  * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
3*1031c584SApple OSS Distributions  *
4*1031c584SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5*1031c584SApple OSS Distributions  *
6*1031c584SApple OSS Distributions  * This file contains Original Code and/or Modifications of Original Code
7*1031c584SApple OSS Distributions  * as defined in and that are subject to the Apple Public Source License
8*1031c584SApple OSS Distributions  * Version 2.0 (the 'License'). You may not use this file except in
9*1031c584SApple OSS Distributions  * compliance with the License. The rights granted to you under the License
10*1031c584SApple OSS Distributions  * may not be used to create, or enable the creation or redistribution of,
11*1031c584SApple OSS Distributions  * unlawful or unlicensed copies of an Apple operating system, or to
12*1031c584SApple OSS Distributions  * circumvent, violate, or enable the circumvention or violation of, any
13*1031c584SApple OSS Distributions  * terms of an Apple operating system software license agreement.
14*1031c584SApple OSS Distributions  *
15*1031c584SApple OSS Distributions  * Please obtain a copy of the License at
16*1031c584SApple OSS Distributions  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17*1031c584SApple OSS Distributions  *
18*1031c584SApple OSS Distributions  * The Original Code and all software distributed under the License are
19*1031c584SApple OSS Distributions  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20*1031c584SApple OSS Distributions  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21*1031c584SApple OSS Distributions  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22*1031c584SApple OSS Distributions  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23*1031c584SApple OSS Distributions  * Please see the License for the specific language governing rights and
24*1031c584SApple OSS Distributions  * limitations under the License.
25*1031c584SApple OSS Distributions  *
26*1031c584SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27*1031c584SApple OSS Distributions  */
28*1031c584SApple OSS Distributions /*
29*1031c584SApple OSS Distributions  * @OSF_COPYRIGHT@
30*1031c584SApple OSS Distributions  */
31*1031c584SApple OSS Distributions /*
32*1031c584SApple OSS Distributions  * Mach Operating System
33*1031c584SApple OSS Distributions  * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
34*1031c584SApple OSS Distributions  * All Rights Reserved.
35*1031c584SApple OSS Distributions  *
36*1031c584SApple OSS Distributions  * Permission to use, copy, modify and distribute this software and its
37*1031c584SApple OSS Distributions  * documentation is hereby granted, provided that both the copyright
38*1031c584SApple OSS Distributions  * notice and this permission notice appear in all copies of the
39*1031c584SApple OSS Distributions  * software, derivative works or modified versions, and any portions
40*1031c584SApple OSS Distributions  * thereof, and that both notices appear in supporting documentation.
41*1031c584SApple OSS Distributions  *
42*1031c584SApple OSS Distributions  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
43*1031c584SApple OSS Distributions  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
44*1031c584SApple OSS Distributions  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
45*1031c584SApple OSS Distributions  *
46*1031c584SApple OSS Distributions  * Carnegie Mellon requests users of this software to return to
47*1031c584SApple OSS Distributions  *
48*1031c584SApple OSS Distributions  *  Software Distribution Coordinator  or  [email protected]
49*1031c584SApple OSS Distributions  *  School of Computer Science
50*1031c584SApple OSS Distributions  *  Carnegie Mellon University
51*1031c584SApple OSS Distributions  *  Pittsburgh PA 15213-3890
52*1031c584SApple OSS Distributions  *
53*1031c584SApple OSS Distributions  * any improvements or extensions that they make and grant Carnegie Mellon
54*1031c584SApple OSS Distributions  * the rights to redistribute these changes.
55*1031c584SApple OSS Distributions  */
56*1031c584SApple OSS Distributions /*
57*1031c584SApple OSS Distributions  */
58*1031c584SApple OSS Distributions 
59*1031c584SApple OSS Distributions #ifndef _KERN_TIMER_H_
60*1031c584SApple OSS Distributions #define _KERN_TIMER_H_
61*1031c584SApple OSS Distributions 
62*1031c584SApple OSS Distributions #include <kern/kern_types.h>
63*1031c584SApple OSS Distributions 
64*1031c584SApple OSS Distributions /*
65*1031c584SApple OSS Distributions  * Definitions for high resolution timers.
66*1031c584SApple OSS Distributions  */
67*1031c584SApple OSS Distributions 
68*1031c584SApple OSS Distributions #if __LP64__
69*1031c584SApple OSS Distributions #define TIMER_ALIGNMENT
70*1031c584SApple OSS Distributions #else
71*1031c584SApple OSS Distributions #define TIMER_ALIGNMENT __attribute__((packed, aligned(4)))
72*1031c584SApple OSS Distributions #endif
73*1031c584SApple OSS Distributions 
74*1031c584SApple OSS Distributions struct timer {
75*1031c584SApple OSS Distributions 	uint64_t tstamp;
76*1031c584SApple OSS Distributions #if defined(__LP64__)
77*1031c584SApple OSS Distributions 	uint64_t all_bits;
78*1031c584SApple OSS Distributions #else /* defined(__LP64__) */
79*1031c584SApple OSS Distributions 	/* A check word on the high portion allows atomic updates. */
80*1031c584SApple OSS Distributions 	uint32_t low_bits;
81*1031c584SApple OSS Distributions 	uint32_t high_bits;
82*1031c584SApple OSS Distributions 	uint32_t high_bits_check;
83*1031c584SApple OSS Distributions #endif /* !defined(__LP64__) */
84*1031c584SApple OSS Distributions } TIMER_ALIGNMENT;
85*1031c584SApple OSS Distributions 
86*1031c584SApple OSS Distributions typedef struct timer timer_data_t, *timer_t;
87*1031c584SApple OSS Distributions 
88*1031c584SApple OSS Distributions /*
89*1031c584SApple OSS Distributions  * Initialize the `timer`.
90*1031c584SApple OSS Distributions  */
91*1031c584SApple OSS Distributions void timer_init(timer_t timer);
92*1031c584SApple OSS Distributions 
93*1031c584SApple OSS Distributions /*
94*1031c584SApple OSS Distributions  * Start the `timer` at time `tstamp`.
95*1031c584SApple OSS Distributions  */
96*1031c584SApple OSS Distributions void timer_start(timer_t timer, uint64_t tstamp);
97*1031c584SApple OSS Distributions 
98*1031c584SApple OSS Distributions /*
99*1031c584SApple OSS Distributions  * Stop the `timer` and update it with time `tstamp`.
100*1031c584SApple OSS Distributions  */
101*1031c584SApple OSS Distributions void timer_stop(timer_t timer, uint64_t tstamp);
102*1031c584SApple OSS Distributions 
103*1031c584SApple OSS Distributions /*
104*1031c584SApple OSS Distributions  * Update the `timer` at time `tstamp`, leaving it running.
105*1031c584SApple OSS Distributions  */
106*1031c584SApple OSS Distributions void timer_update(timer_t timer, uint64_t tstamp);
107*1031c584SApple OSS Distributions 
108*1031c584SApple OSS Distributions /*
109*1031c584SApple OSS Distributions  * Read the accumulated time of `timer`.
110*1031c584SApple OSS Distributions  */
111*1031c584SApple OSS Distributions #if defined(__LP64__)
112*1031c584SApple OSS Distributions static inline
113*1031c584SApple OSS Distributions uint64_t
timer_grab(timer_t timer)114*1031c584SApple OSS Distributions timer_grab(timer_t timer)
115*1031c584SApple OSS Distributions {
116*1031c584SApple OSS Distributions 	return timer->all_bits;
117*1031c584SApple OSS Distributions }
118*1031c584SApple OSS Distributions #else /* defined(__LP64__) */
119*1031c584SApple OSS Distributions uint64_t timer_grab(timer_t timer);
120*1031c584SApple OSS Distributions #endif /* !defined(__LP64__) */
121*1031c584SApple OSS Distributions 
122*1031c584SApple OSS Distributions #endif /* _KERN_TIMER_H_ */
123