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2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
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27 * Mach Operating System
28 * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
29 * All Rights Reserved.
31 * Permission to use, copy, modify and distribute this software and its
32 * documentation is hereby granted, provided that both the copyright
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34 * software, derivative works or modified versions, and any portions
35 * thereof, and that both notices appear in supporting documentation.
37 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
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39 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
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44 * School of Computer Science
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48 * any improvements or extensions that they make and grant Carnegie Mellon
49 * the rights to redistribute these changes.
54 #include <stat_time.h>
55 #include <machine_timer_routines.h>
57 #include <mach/kern_return.h>
58 #include <mach/port.h>
59 #include <kern/queue.h>
60 #include <kern/processor.h>
61 #include <kern/thread.h>
62 #include <kern/sched_prim.h>
63 #include <kern/timer.h>
66 * timer_init initializes a timer.
74 timer
->high_bits_check
= 0;
77 #endif /* STAT_TIME */
81 * Calculate the difference between a timer
82 * and saved value, and update the saved value.
89 uint64_t new, old
= *save
;
91 *save
= new = timer_grab(timer
);
99 * Update the current timer (if any)
100 * and start the new timer, which
101 * could be either the same or NULL.
103 * Called with interrupts disabled.
110 processor_t processor
= current_processor();
112 uint32_t old_low
, low
;
115 * Update current timer.
117 timer
= PROCESSOR_DATA(processor
, current_timer
);
119 old_low
= timer
->low_bits
;
120 low
= old_low
+ tstamp
- timer
->tstamp
;
122 timer_update(timer
, timer
->high_bits
+ 1, low
);
124 timer
->low_bits
= low
;
130 PROCESSOR_DATA(processor
, current_timer
) = new_timer
;
131 if (new_timer
!= NULL
)
132 new_timer
->tstamp
= tstamp
;
135 #if MACHINE_TIMER_ROUTINES
138 * Machine-dependent code implements the timer event routine.
141 #else /* MACHINE_TIMER_ROUTINES */
144 * Update the current timer and start
145 * the new timer. Requires a current
148 * Called with interrupts disabled.
155 processor_t processor
= current_processor();
157 uint32_t old_low
, low
;
160 * Update current timer.
162 timer
= PROCESSOR_DATA(processor
, current_timer
);
163 old_low
= timer
->low_bits
;
164 low
= old_low
+ tstamp
- timer
->tstamp
;
166 timer_update(timer
, timer
->high_bits
+ 1, low
);
168 timer
->low_bits
= low
;
173 PROCESSOR_DATA(processor
, current_timer
) = new_timer
;
174 new_timer
->tstamp
= tstamp
;
177 #endif /* MACHINE_TIMER_ROUTINES */
179 #endif /* STAT_TIME */