/* [<][>][^][v][top][bottom][index][help] */
1 /*
2 * Copyright (c) 2000, 2001, 2002, 2003, 2004, 2005, 2008, 2009
3 * The President and Fellows of Harvard College.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE UNIVERSITY OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 #ifndef _CLOCK_H_
31 #define _CLOCK_H_
32
33 #include "opt-synchprobs.h"
34
35 /*
36 * Time-related definitions.
37 *
38 * hardclock() is called on every CPU HZ times a second, possibly only
39 * when the CPU is not idle, for scheduling.
40 *
41 * timerclock() is called on one CPU once a second to allow simple
42 * timed operations. (This is a fairly simpleminded interface.)
43 *
44 * gettime() may be used to fetch the current time of day.
45 * getinterval() computes the time from time1 to time2.
46 *
47 * XXX we have struct timespec now, let's use it.
48 */
49
50 /* hardclocks per second */
51 #if OPT_SYNCHPROBS
52 /* Make synchronization more exciting :) */
53 #define HZ 10000
54 #else
55 /* More realistic value */
56 #define HZ 100
57 #endif
58
59 void hardclock_bootstrap(void);
60
61 void hardclock(void);
62 void timerclock(void);
63
64 void gettime(time_t *seconds, uint32_t *nanoseconds);
65
66 void getinterval(time_t secs1, uint32_t nsecs,
67 time_t secs2, uint32_t nsecs2,
68 time_t *rsecs, uint32_t *rnsecs);
69
70 /*
71 * clocksleep() suspends execution for the requested number of seconds,
72 * like userlevel sleep(3). (Don't confuse it with wchan_sleep.)
73 */
74 void clocksleep(int seconds);
75
76
77 #endif /* _CLOCK_H_ */