xref: /xnu-10063.121.3/osfmk/kern/timer.h (revision 2c2f96dc2b9a4408a43d3150ae9c105355ca3daa)
1*2c2f96dcSApple OSS Distributions /*
2*2c2f96dcSApple OSS Distributions  * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
3*2c2f96dcSApple OSS Distributions  *
4*2c2f96dcSApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5*2c2f96dcSApple OSS Distributions  *
6*2c2f96dcSApple OSS Distributions  * This file contains Original Code and/or Modifications of Original Code
7*2c2f96dcSApple OSS Distributions  * as defined in and that are subject to the Apple Public Source License
8*2c2f96dcSApple OSS Distributions  * Version 2.0 (the 'License'). You may not use this file except in
9*2c2f96dcSApple OSS Distributions  * compliance with the License. The rights granted to you under the License
10*2c2f96dcSApple OSS Distributions  * may not be used to create, or enable the creation or redistribution of,
11*2c2f96dcSApple OSS Distributions  * unlawful or unlicensed copies of an Apple operating system, or to
12*2c2f96dcSApple OSS Distributions  * circumvent, violate, or enable the circumvention or violation of, any
13*2c2f96dcSApple OSS Distributions  * terms of an Apple operating system software license agreement.
14*2c2f96dcSApple OSS Distributions  *
15*2c2f96dcSApple OSS Distributions  * Please obtain a copy of the License at
16*2c2f96dcSApple OSS Distributions  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17*2c2f96dcSApple OSS Distributions  *
18*2c2f96dcSApple OSS Distributions  * The Original Code and all software distributed under the License are
19*2c2f96dcSApple OSS Distributions  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20*2c2f96dcSApple OSS Distributions  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21*2c2f96dcSApple OSS Distributions  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22*2c2f96dcSApple OSS Distributions  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23*2c2f96dcSApple OSS Distributions  * Please see the License for the specific language governing rights and
24*2c2f96dcSApple OSS Distributions  * limitations under the License.
25*2c2f96dcSApple OSS Distributions  *
26*2c2f96dcSApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27*2c2f96dcSApple OSS Distributions  */
28*2c2f96dcSApple OSS Distributions /*
29*2c2f96dcSApple OSS Distributions  * @OSF_COPYRIGHT@
30*2c2f96dcSApple OSS Distributions  */
31*2c2f96dcSApple OSS Distributions /*
32*2c2f96dcSApple OSS Distributions  * Mach Operating System
33*2c2f96dcSApple OSS Distributions  * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
34*2c2f96dcSApple OSS Distributions  * All Rights Reserved.
35*2c2f96dcSApple OSS Distributions  *
36*2c2f96dcSApple OSS Distributions  * Permission to use, copy, modify and distribute this software and its
37*2c2f96dcSApple OSS Distributions  * documentation is hereby granted, provided that both the copyright
38*2c2f96dcSApple OSS Distributions  * notice and this permission notice appear in all copies of the
39*2c2f96dcSApple OSS Distributions  * software, derivative works or modified versions, and any portions
40*2c2f96dcSApple OSS Distributions  * thereof, and that both notices appear in supporting documentation.
41*2c2f96dcSApple OSS Distributions  *
42*2c2f96dcSApple OSS Distributions  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
43*2c2f96dcSApple OSS Distributions  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
44*2c2f96dcSApple OSS Distributions  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
45*2c2f96dcSApple OSS Distributions  *
46*2c2f96dcSApple OSS Distributions  * Carnegie Mellon requests users of this software to return to
47*2c2f96dcSApple OSS Distributions  *
48*2c2f96dcSApple OSS Distributions  *  Software Distribution Coordinator  or  [email protected]
49*2c2f96dcSApple OSS Distributions  *  School of Computer Science
50*2c2f96dcSApple OSS Distributions  *  Carnegie Mellon University
51*2c2f96dcSApple OSS Distributions  *  Pittsburgh PA 15213-3890
52*2c2f96dcSApple OSS Distributions  *
53*2c2f96dcSApple OSS Distributions  * any improvements or extensions that they make and grant Carnegie Mellon
54*2c2f96dcSApple OSS Distributions  * the rights to redistribute these changes.
55*2c2f96dcSApple OSS Distributions  */
56*2c2f96dcSApple OSS Distributions /*
57*2c2f96dcSApple OSS Distributions  */
58*2c2f96dcSApple OSS Distributions 
59*2c2f96dcSApple OSS Distributions #ifndef _KERN_TIMER_H_
60*2c2f96dcSApple OSS Distributions #define _KERN_TIMER_H_
61*2c2f96dcSApple OSS Distributions 
62*2c2f96dcSApple OSS Distributions #include <kern/kern_types.h>
63*2c2f96dcSApple OSS Distributions 
64*2c2f96dcSApple OSS Distributions /*
65*2c2f96dcSApple OSS Distributions  * Definitions for high resolution timers.
66*2c2f96dcSApple OSS Distributions  */
67*2c2f96dcSApple OSS Distributions 
68*2c2f96dcSApple OSS Distributions #if __LP64__
69*2c2f96dcSApple OSS Distributions #define TIMER_ALIGNMENT
70*2c2f96dcSApple OSS Distributions #else
71*2c2f96dcSApple OSS Distributions #define TIMER_ALIGNMENT __attribute__((packed, aligned(4)))
72*2c2f96dcSApple OSS Distributions #endif
73*2c2f96dcSApple OSS Distributions 
74*2c2f96dcSApple OSS Distributions struct timer {
75*2c2f96dcSApple OSS Distributions 	uint64_t tstamp;
76*2c2f96dcSApple OSS Distributions #if defined(__LP64__)
77*2c2f96dcSApple OSS Distributions 	uint64_t all_bits;
78*2c2f96dcSApple OSS Distributions #else /* defined(__LP64__) */
79*2c2f96dcSApple OSS Distributions 	/* A check word on the high portion allows atomic updates. */
80*2c2f96dcSApple OSS Distributions 	uint32_t low_bits;
81*2c2f96dcSApple OSS Distributions 	uint32_t high_bits;
82*2c2f96dcSApple OSS Distributions 	uint32_t high_bits_check;
83*2c2f96dcSApple OSS Distributions #endif /* !defined(__LP64__) */
84*2c2f96dcSApple OSS Distributions } TIMER_ALIGNMENT;
85*2c2f96dcSApple OSS Distributions 
86*2c2f96dcSApple OSS Distributions typedef struct timer timer_data_t, *timer_t;
87*2c2f96dcSApple OSS Distributions 
88*2c2f96dcSApple OSS Distributions /*
89*2c2f96dcSApple OSS Distributions  * Initialize the `timer`.
90*2c2f96dcSApple OSS Distributions  */
91*2c2f96dcSApple OSS Distributions void timer_init(timer_t timer);
92*2c2f96dcSApple OSS Distributions 
93*2c2f96dcSApple OSS Distributions /*
94*2c2f96dcSApple OSS Distributions  * Start the `timer` at time `tstamp`.
95*2c2f96dcSApple OSS Distributions  */
96*2c2f96dcSApple OSS Distributions void timer_start(timer_t timer, uint64_t tstamp);
97*2c2f96dcSApple OSS Distributions 
98*2c2f96dcSApple OSS Distributions /*
99*2c2f96dcSApple OSS Distributions  * Stop the `timer` and update it with time `tstamp`.
100*2c2f96dcSApple OSS Distributions  */
101*2c2f96dcSApple OSS Distributions void timer_stop(timer_t timer, uint64_t tstamp);
102*2c2f96dcSApple OSS Distributions 
103*2c2f96dcSApple OSS Distributions /*
104*2c2f96dcSApple OSS Distributions  * Update the `timer` at time `tstamp`, leaving it running.
105*2c2f96dcSApple OSS Distributions  */
106*2c2f96dcSApple OSS Distributions void timer_update(timer_t timer, uint64_t tstamp);
107*2c2f96dcSApple OSS Distributions 
108*2c2f96dcSApple OSS Distributions /*
109*2c2f96dcSApple OSS Distributions  * Read the accumulated time of `timer`.
110*2c2f96dcSApple OSS Distributions  */
111*2c2f96dcSApple OSS Distributions #if defined(__LP64__)
112*2c2f96dcSApple OSS Distributions static inline
113*2c2f96dcSApple OSS Distributions uint64_t
timer_grab(timer_t timer)114*2c2f96dcSApple OSS Distributions timer_grab(timer_t timer)
115*2c2f96dcSApple OSS Distributions {
116*2c2f96dcSApple OSS Distributions 	return timer->all_bits;
117*2c2f96dcSApple OSS Distributions }
118*2c2f96dcSApple OSS Distributions #else /* defined(__LP64__) */
119*2c2f96dcSApple OSS Distributions uint64_t timer_grab(timer_t timer);
120*2c2f96dcSApple OSS Distributions #endif /* !defined(__LP64__) */
121*2c2f96dcSApple OSS Distributions 
122*2c2f96dcSApple OSS Distributions #endif /* _KERN_TIMER_H_ */
123