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jiffies.h revision 1.12 
      1 /*	$NetBSD: jiffies.h,v 1.12 2018/08/27 13:57:50 riastradh Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2013 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Taylor R. Campbell.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #ifndef _LINUX_JIFFIES_H_
     33 #define _LINUX_JIFFIES_H_
     34 
     35 #include <sys/param.h>
     36 #include <sys/kernel.h>
     37 
     38 #define	jiffies		hardclock_ticks
     39 #define	jiffies_64	hardclock_ticks /* XXX */
     40 
     41 /* XXX Er, what?  */
     42 #define	MAX_JIFFY_OFFSET	((INT_MAX >> 1) - 1)
     43 
     44 static inline uint64_t
     45 get_jiffies_64(void)
     46 {
     47 
     48 	return (uint64_t)(unsigned)hardclock_ticks;
     49 }
     50 
     51 static inline uint64_t
     52 nsecs_to_jiffies64(uint64_t nsec)
     53 {
     54 
     55 	/* XXX Arbitrary cutoff, should review the arithmetic.  */
     56 	if (((1000000000 % hz) == 0) || (nsec >= 20000000000ul))
     57 		return (nsec/1000000000)*hz;
     58 	else
     59 		return (nsec*hz)/1000000000;
     60 }
     61 
     62 static inline uint32_t
     63 nsecs_to_jiffies(uint64_t nsec)
     64 {
     65 
     66 	/* XXX Not sure what else to do but truncate...  */
     67 	return (uint32_t)nsecs_to_jiffies64(nsec);
     68 }
     69 
     70 static inline unsigned int
     71 msecs_to_jiffies(unsigned int msec)
     72 {
     73 	return mstohz(msec);
     74 }
     75 
     76 static inline unsigned int
     77 jiffies_to_msecs(unsigned int j)
     78 {
     79 	return hztoms(j);
     80 }
     81 
     82 static inline unsigned int
     83 usecs_to_jiffies(unsigned int usec)
     84 {
     85 	const struct timeval tv = {
     86 		.tv_sec = usec / 1000000,
     87 		.tv_usec = usec % 1000000,
     88 	};
     89 
     90 	return tvtohz(&tv);
     91 }
     92 
     93 static inline unsigned int
     94 jiffies_to_usecs(unsigned int j)
     95 {
     96 
     97 	/* XXX Do better arithmetic.  */
     98 	return (unsigned int)((unsigned long)j*1000000/hz);
     99 }
    100 
    101 static inline unsigned int
    102 timespec_to_jiffies(const struct timespec *ts)
    103 {
    104 	return tstohz(ts);
    105 }
    106 
    107 /* XXX long is the wrong type here times...  */
    108 
    109 #define	__linux_time_compare(A, OP, B)	(((long)(A) - (long)(B)) OP 0)
    110 
    111 static inline bool
    112 time_after(unsigned long a, unsigned long b)
    113 {
    114 	return __linux_time_compare(a, >, b);
    115 }
    116 
    117 static inline bool
    118 time_after_eq(unsigned long a, unsigned long b)
    119 {
    120 	return __linux_time_compare(a, >=, b);
    121 }
    122 
    123 static inline bool
    124 time_before(unsigned long a, unsigned long b)
    125 {
    126 	return __linux_time_compare(a, <, b);
    127 }
    128 
    129 static inline bool
    130 time_before_eq(unsigned long a, unsigned long b)
    131 {
    132 	return __linux_time_compare(a, <=, b);
    133 }
    134 
    135 #endif  /* _LINUX_JIFFIES_H_ */
    136