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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _LINUX_JIFFIES_H
2#define _LINUX_JIFFIES_H
3
Roman Zippelf8bd2252008-05-01 04:34:31 -07004#include <linux/math64.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07005#include <linux/kernel.h>
6#include <linux/types.h>
7#include <linux/time.h>
8#include <linux/timex.h>
9#include <asm/param.h> /* for HZ */
Nicholas Mc Guireca42aaf2015-05-18 14:19:13 +020010#include <generated/timeconst.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011
12/*
13 * The following defines establish the engineering parameters of the PLL
14 * model. The HZ variable establishes the timer interrupt frequency, 100 Hz
15 * for the SunOS kernel, 256 Hz for the Ultrix kernel and 1024 Hz for the
16 * OSF/1 kernel. The SHIFT_HZ define expresses the same value as the
17 * nearest power of two in order to avoid hardware multiply operations.
18 */
19#if HZ >= 12 && HZ < 24
20# define SHIFT_HZ 4
21#elif HZ >= 24 && HZ < 48
22# define SHIFT_HZ 5
23#elif HZ >= 48 && HZ < 96
24# define SHIFT_HZ 6
25#elif HZ >= 96 && HZ < 192
26# define SHIFT_HZ 7
27#elif HZ >= 192 && HZ < 384
28# define SHIFT_HZ 8
29#elif HZ >= 384 && HZ < 768
30# define SHIFT_HZ 9
31#elif HZ >= 768 && HZ < 1536
32# define SHIFT_HZ 10
Pavel Macheke118ade2008-01-25 21:08:34 +010033#elif HZ >= 1536 && HZ < 3072
34# define SHIFT_HZ 11
35#elif HZ >= 3072 && HZ < 6144
36# define SHIFT_HZ 12
37#elif HZ >= 6144 && HZ < 12288
38# define SHIFT_HZ 13
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#else
Robert P. J. Day37679012008-04-21 22:56:14 +000040# error Invalid value of HZ.
Linus Torvalds1da177e2005-04-16 15:20:36 -070041#endif
42
Lucas De Marchi25985ed2011-03-30 22:57:33 -030043/* Suppose we want to divide two numbers NOM and DEN: NOM/DEN, then we can
Linus Torvalds1da177e2005-04-16 15:20:36 -070044 * improve accuracy by shifting LSH bits, hence calculating:
45 * (NOM << LSH) / DEN
46 * This however means trouble for large NOM, because (NOM << LSH) may no
47 * longer fit in 32 bits. The following way of calculating this gives us
48 * some slack, under the following conditions:
49 * - (NOM / DEN) fits in (32 - LSH) bits.
50 * - (NOM % DEN) fits in (32 - LSH) bits.
51 */
Uwe Zeisberger0d94df52006-07-30 03:04:02 -070052#define SH_DIV(NOM,DEN,LSH) ( (((NOM) / (DEN)) << (LSH)) \
53 + ((((NOM) % (DEN)) << (LSH)) + (DEN) / 2) / (DEN))
Linus Torvalds1da177e2005-04-16 15:20:36 -070054
Catalin Marinasa7ea3bb2012-07-27 14:48:09 -040055/* LATCH is used in the interval timer and ftape setup. */
Arnd Bergmann015a8302012-09-28 23:36:17 +020056#define LATCH ((CLOCK_TICK_RATE + HZ/2) / HZ) /* For divider */
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
John Stultzb3c869d2012-09-04 12:42:27 -040058extern int register_refined_jiffies(long clock_tick_rate);
Linus Torvalds1da177e2005-04-16 15:20:36 -070059
John Stultz02ab20a2012-07-27 14:48:10 -040060/* TICK_NSEC is the time between ticks in nsec assuming SHIFTED_HZ */
John Stultzb3c869d2012-09-04 12:42:27 -040061#define TICK_NSEC ((NSEC_PER_SEC+HZ/2)/HZ)
Linus Torvalds1da177e2005-04-16 15:20:36 -070062
63/* TICK_USEC is the time between ticks in usec assuming fake USER_HZ */
64#define TICK_USEC ((1000000UL + USER_HZ/2) / USER_HZ)
65
Linus Torvalds1da177e2005-04-16 15:20:36 -070066/* some arch's have a small-data section that can be accessed register-relative
67 * but that can only take up to, say, 4-byte variables. jiffies being part of
68 * an 8-byte variable may not be correctly accessed unless we force the issue
69 */
70#define __jiffy_data __attribute__((section(".data")))
71
72/*
Chase Venters98c4f0c2006-11-30 04:53:49 +010073 * The 64-bit value is not atomic - you MUST NOT read it
John Stultzd6ad4182012-02-28 16:50:11 -080074 * without sampling the sequence number in jiffies_lock.
Linus Torvalds1da177e2005-04-16 15:20:36 -070075 * get_jiffies_64() will do this for you as appropriate.
76 */
77extern u64 __jiffy_data jiffies_64;
78extern unsigned long volatile __jiffy_data jiffies;
79
80#if (BITS_PER_LONG < 64)
81u64 get_jiffies_64(void);
82#else
83static inline u64 get_jiffies_64(void)
84{
85 return (u64)jiffies;
86}
87#endif
88
89/*
90 * These inlines deal with timer wrapping correctly. You are
91 * strongly encouraged to use them
92 * 1. Because people otherwise forget
93 * 2. Because if the timer wrap changes in future you won't have to
94 * alter your driver code.
95 *
96 * time_after(a,b) returns true if the time a is after time b.
97 *
98 * Do this with "<0" and ">=0" to only test the sign of the result. A
99 * good compiler would generate better code (and a really good compiler
100 * wouldn't care). Gcc is currently neither.
101 */
102#define time_after(a,b) \
103 (typecheck(unsigned long, a) && \
104 typecheck(unsigned long, b) && \
Paul E. McKenney5a581b32013-07-27 03:53:54 -0700105 ((long)((b) - (a)) < 0))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106#define time_before(a,b) time_after(b,a)
107
108#define time_after_eq(a,b) \
109 (typecheck(unsigned long, a) && \
110 typecheck(unsigned long, b) && \
Paul E. McKenney5a581b32013-07-27 03:53:54 -0700111 ((long)((a) - (b)) >= 0))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112#define time_before_eq(a,b) time_after_eq(b,a)
113
Peter Staubach64672d52008-12-23 15:21:56 -0500114/*
115 * Calculate whether a is in the range of [b, c].
116 */
Fabio Olive Leitec7e15962007-07-26 22:59:00 -0300117#define time_in_range(a,b,c) \
118 (time_after_eq(a,b) && \
119 time_before_eq(a,c))
120
Peter Staubach64672d52008-12-23 15:21:56 -0500121/*
122 * Calculate whether a is in the range of [b, c).
123 */
124#define time_in_range_open(a,b,c) \
125 (time_after_eq(a,b) && \
126 time_before(a,c))
127
Dmitriy Zavin3b171672006-09-26 10:52:42 +0200128/* Same as above, but does so with platform independent 64bit types.
129 * These must be used when utilizing jiffies_64 (i.e. return value of
130 * get_jiffies_64() */
131#define time_after64(a,b) \
132 (typecheck(__u64, a) && \
133 typecheck(__u64, b) && \
Paul E. McKenney5a581b32013-07-27 03:53:54 -0700134 ((__s64)((b) - (a)) < 0))
Dmitriy Zavin3b171672006-09-26 10:52:42 +0200135#define time_before64(a,b) time_after64(b,a)
136
137#define time_after_eq64(a,b) \
138 (typecheck(__u64, a) && \
139 typecheck(__u64, b) && \
Paul E. McKenney5a581b32013-07-27 03:53:54 -0700140 ((__s64)((a) - (b)) >= 0))
Dmitriy Zavin3b171672006-09-26 10:52:42 +0200141#define time_before_eq64(a,b) time_after_eq64(b,a)
142
Eliezer Tamir1bc27742013-07-02 23:22:47 +0300143#define time_in_range64(a, b, c) \
144 (time_after_eq64(a, b) && \
145 time_before_eq64(a, c))
146
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147/*
Dave Young3f34d022008-04-18 13:38:57 -0700148 * These four macros compare jiffies and 'a' for convenience.
149 */
150
151/* time_is_before_jiffies(a) return true if a is before jiffies */
152#define time_is_before_jiffies(a) time_after(jiffies, a)
153
154/* time_is_after_jiffies(a) return true if a is after jiffies */
155#define time_is_after_jiffies(a) time_before(jiffies, a)
156
157/* time_is_before_eq_jiffies(a) return true if a is before or equal to jiffies*/
158#define time_is_before_eq_jiffies(a) time_after_eq(jiffies, a)
159
160/* time_is_after_eq_jiffies(a) return true if a is after or equal to jiffies*/
161#define time_is_after_eq_jiffies(a) time_before_eq(jiffies, a)
162
163/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164 * Have the 32 bit jiffies value wrap 5 minutes after boot
165 * so jiffies wrap bugs show up earlier.
166 */
167#define INITIAL_JIFFIES ((unsigned long)(unsigned int) (-300*HZ))
168
169/*
170 * Change timeval to jiffies, trying to avoid the
171 * most obvious overflows..
172 *
173 * And some not so obvious.
174 *
Ingo Molnar9f907c02007-02-16 01:27:29 -0800175 * Note that we don't want to return LONG_MAX, because
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 * for various timeout reasons we often end up having
177 * to wait "jiffies+1" in order to guarantee that we wait
178 * at _least_ "jiffies" - so "jiffies+1" had better still
179 * be positive.
180 */
Ingo Molnar9f907c02007-02-16 01:27:29 -0800181#define MAX_JIFFY_OFFSET ((LONG_MAX >> 1)-1)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182
Randy Dunlapbfe8df32007-10-16 01:23:46 -0700183extern unsigned long preset_lpj;
184
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185/*
186 * We want to do realistic conversions of time so we need to use the same
187 * values the update wall clock code uses as the jiffies size. This value
188 * is: TICK_NSEC (which is defined in timex.h). This
Li Zefan3eb05672008-02-08 04:19:25 -0800189 * is a constant and is in nanoseconds. We will use scaled math
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 * with a set of scales defined here as SEC_JIFFIE_SC, USEC_JIFFIE_SC and
191 * NSEC_JIFFIE_SC. Note that these defines contain nothing but
192 * constants and so are computed at compile time. SHIFT_HZ (computed in
193 * timex.h) adjusts the scaling for different HZ values.
194
195 * Scaled math??? What is that?
196 *
197 * Scaled math is a way to do integer math on values that would,
198 * otherwise, either overflow, underflow, or cause undesired div
199 * instructions to appear in the execution path. In short, we "scale"
200 * up the operands so they take more bits (more precision, less
201 * underflow), do the desired operation and then "scale" the result back
202 * by the same amount. If we do the scaling by shifting we avoid the
203 * costly mpy and the dastardly div instructions.
204
205 * Suppose, for example, we want to convert from seconds to jiffies
206 * where jiffies is defined in nanoseconds as NSEC_PER_JIFFIE. The
207 * simple math is: jiff = (sec * NSEC_PER_SEC) / NSEC_PER_JIFFIE; We
208 * observe that (NSEC_PER_SEC / NSEC_PER_JIFFIE) is a constant which we
209 * might calculate at compile time, however, the result will only have
210 * about 3-4 bits of precision (less for smaller values of HZ).
211 *
212 * So, we scale as follows:
213 * jiff = (sec) * (NSEC_PER_SEC / NSEC_PER_JIFFIE);
214 * jiff = ((sec) * ((NSEC_PER_SEC * SCALE)/ NSEC_PER_JIFFIE)) / SCALE;
215 * Then we make SCALE a power of two so:
216 * jiff = ((sec) * ((NSEC_PER_SEC << SCALE)/ NSEC_PER_JIFFIE)) >> SCALE;
217 * Now we define:
218 * #define SEC_CONV = ((NSEC_PER_SEC << SCALE)/ NSEC_PER_JIFFIE))
219 * jiff = (sec * SEC_CONV) >> SCALE;
220 *
221 * Often the math we use will expand beyond 32-bits so we tell C how to
222 * do this and pass the 64-bit result of the mpy through the ">> SCALE"
223 * which should take the result back to 32-bits. We want this expansion
224 * to capture as much precision as possible. At the same time we don't
225 * want to overflow so we pick the SCALE to avoid this. In this file,
226 * that means using a different scale for each range of HZ values (as
227 * defined in timex.h).
228 *
229 * For those who want to know, gcc will give a 64-bit result from a "*"
230 * operator if the result is a long long AND at least one of the
231 * operands is cast to long long (usually just prior to the "*" so as
232 * not to confuse it into thinking it really has a 64-bit operand,
Li Zefan3eb05672008-02-08 04:19:25 -0800233 * which, buy the way, it can do, but it takes more code and at least 2
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234 * mpys).
235
236 * We also need to be aware that one second in nanoseconds is only a
237 * couple of bits away from overflowing a 32-bit word, so we MUST use
238 * 64-bits to get the full range time in nanoseconds.
239
240 */
241
242/*
243 * Here are the scales we will use. One for seconds, nanoseconds and
244 * microseconds.
245 *
246 * Within the limits of cpp we do a rough cut at the SEC_JIFFIE_SC and
247 * check if the sign bit is set. If not, we bump the shift count by 1.
248 * (Gets an extra bit of precision where we can use it.)
249 * We know it is set for HZ = 1024 and HZ = 100 not for 1000.
250 * Haven't tested others.
251
252 * Limits of cpp (for #if expressions) only long (no long long), but
253 * then we only need the most signicant bit.
254 */
255
256#define SEC_JIFFIE_SC (31 - SHIFT_HZ)
257#if !((((NSEC_PER_SEC << 2) / TICK_NSEC) << (SEC_JIFFIE_SC - 2)) & 0x80000000)
258#undef SEC_JIFFIE_SC
259#define SEC_JIFFIE_SC (32 - SHIFT_HZ)
260#endif
261#define NSEC_JIFFIE_SC (SEC_JIFFIE_SC + 29)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262#define SEC_CONVERSION ((unsigned long)((((u64)NSEC_PER_SEC << SEC_JIFFIE_SC) +\
263 TICK_NSEC -1) / (u64)TICK_NSEC))
264
265#define NSEC_CONVERSION ((unsigned long)((((u64)1 << NSEC_JIFFIE_SC) +\
266 TICK_NSEC -1) / (u64)TICK_NSEC))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267/*
268 * The maximum jiffie value is (MAX_INT >> 1). Here we translate that
269 * into seconds. The 64-bit case will overflow if we are not careful,
270 * so use the messy SH_DIV macro to do it. Still all constants.
271 */
272#if BITS_PER_LONG < 64
273# define MAX_SEC_IN_JIFFIES \
274 (long)((u64)((u64)MAX_JIFFY_OFFSET * TICK_NSEC) / NSEC_PER_SEC)
275#else /* take care of overflow on 64 bits machines */
276# define MAX_SEC_IN_JIFFIES \
277 (SH_DIV((MAX_JIFFY_OFFSET >> SEC_JIFFIE_SC) * TICK_NSEC, NSEC_PER_SEC, 1) - 1)
278
279#endif
280
281/*
Ingo Molnar8b9365d2007-02-16 01:27:27 -0800282 * Convert various time units to each other:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 */
Ingo Molnar8b9365d2007-02-16 01:27:27 -0800284extern unsigned int jiffies_to_msecs(const unsigned long j);
285extern unsigned int jiffies_to_usecs(const unsigned long j);
Kevin Hilman8fe8ff02014-01-15 14:51:38 +0100286
287static inline u64 jiffies_to_nsecs(const unsigned long j)
288{
289 return (u64)jiffies_to_usecs(j) * NSEC_PER_USEC;
290}
291
Nicholas Mc Guireca42aaf2015-05-18 14:19:13 +0200292extern unsigned long __msecs_to_jiffies(const unsigned int m);
293#if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ)
294/*
295 * HZ is equal to or smaller than 1000, and 1000 is a nice round
296 * multiple of HZ, divide with the factor between them, but round
297 * upwards:
298 */
299static inline unsigned long _msecs_to_jiffies(const unsigned int m)
300{
Thomas Gleixner4e3d9cb2015-05-19 17:14:51 +0200301 return (m + (MSEC_PER_SEC / HZ) - 1) / (MSEC_PER_SEC / HZ);
Nicholas Mc Guireca42aaf2015-05-18 14:19:13 +0200302}
303#elif HZ > MSEC_PER_SEC && !(HZ % MSEC_PER_SEC)
304/*
305 * HZ is larger than 1000, and HZ is a nice round multiple of 1000 -
306 * simply multiply with the factor between them.
307 *
308 * But first make sure the multiplication result cannot overflow:
309 */
310static inline unsigned long _msecs_to_jiffies(const unsigned int m)
311{
Thomas Gleixner4e3d9cb2015-05-19 17:14:51 +0200312 if (m > jiffies_to_msecs(MAX_JIFFY_OFFSET))
313 return MAX_JIFFY_OFFSET;
314 return m * (HZ / MSEC_PER_SEC);
Nicholas Mc Guireca42aaf2015-05-18 14:19:13 +0200315}
316#else
317/*
318 * Generic case - multiply, round and divide. But first check that if
319 * we are doing a net multiplication, that we wouldn't overflow:
320 */
321static inline unsigned long _msecs_to_jiffies(const unsigned int m)
322{
Thomas Gleixner4e3d9cb2015-05-19 17:14:51 +0200323 if (HZ > MSEC_PER_SEC && m > jiffies_to_msecs(MAX_JIFFY_OFFSET))
324 return MAX_JIFFY_OFFSET;
Nicholas Mc Guireca42aaf2015-05-18 14:19:13 +0200325
Thomas Gleixner4e3d9cb2015-05-19 17:14:51 +0200326 return (MSEC_TO_HZ_MUL32 * m + MSEC_TO_HZ_ADJ32) >> MSEC_TO_HZ_SHR32;
Nicholas Mc Guireca42aaf2015-05-18 14:19:13 +0200327}
328#endif
329/**
330 * msecs_to_jiffies: - convert milliseconds to jiffies
331 * @m: time in milliseconds
332 *
333 * conversion is done as follows:
334 *
335 * - negative values mean 'infinite timeout' (MAX_JIFFY_OFFSET)
336 *
337 * - 'too large' values [that would result in larger than
338 * MAX_JIFFY_OFFSET values] mean 'infinite timeout' too.
339 *
340 * - all other values are converted to jiffies by either multiplying
341 * the input value by a factor or dividing it with a factor and
342 * handling any 32-bit overflows.
343 * for the details see __msecs_to_jiffies()
344 *
Nicholas Mc Guiredaa67b42015-05-18 14:19:14 +0200345 * msecs_to_jiffies() checks for the passed in value being a constant
346 * via __builtin_constant_p() allowing gcc to eliminate most of the
347 * code, __msecs_to_jiffies() is called if the value passed does not
348 * allow constant folding and the actual conversion must be done at
349 * runtime.
350 * the HZ range specific helpers _msecs_to_jiffies() are called both
351 * directly here and from __msecs_to_jiffies() in the case where
352 * constant folding is not possible.
Nicholas Mc Guireca42aaf2015-05-18 14:19:13 +0200353 */
Denys Vlasenkoaccd0b92015-08-04 16:15:16 +0200354static __always_inline unsigned long msecs_to_jiffies(const unsigned int m)
Nicholas Mc Guireca42aaf2015-05-18 14:19:13 +0200355{
Nicholas Mc Guiredaa67b42015-05-18 14:19:14 +0200356 if (__builtin_constant_p(m)) {
357 if ((int)m < 0)
358 return MAX_JIFFY_OFFSET;
359 return _msecs_to_jiffies(m);
360 } else {
361 return __msecs_to_jiffies(m);
362 }
Nicholas Mc Guireca42aaf2015-05-18 14:19:13 +0200363}
364
Nicholas Mc Guireae60d6a2015-05-28 19:09:55 +0200365extern unsigned long __usecs_to_jiffies(const unsigned int u);
Frederic Weisbeckere0758672014-10-10 02:44:01 +0200366#if !(USEC_PER_SEC % HZ)
Nicholas Mc Guireae60d6a2015-05-28 19:09:55 +0200367static inline unsigned long _usecs_to_jiffies(const unsigned int u)
368{
369 return (u + (USEC_PER_SEC / HZ) - 1) / (USEC_PER_SEC / HZ);
370}
Nicholas Mc Guireae60d6a2015-05-28 19:09:55 +0200371#else
372static inline unsigned long _usecs_to_jiffies(const unsigned int u)
373{
374 return (USEC_TO_HZ_MUL32 * u + USEC_TO_HZ_ADJ32)
375 >> USEC_TO_HZ_SHR32;
376}
377#endif
378
Nicholas Mc Guirec569a232015-05-28 19:09:56 +0200379/**
380 * usecs_to_jiffies: - convert microseconds to jiffies
381 * @u: time in microseconds
382 *
383 * conversion is done as follows:
384 *
385 * - 'too large' values [that would result in larger than
386 * MAX_JIFFY_OFFSET values] mean 'infinite timeout' too.
387 *
388 * - all other values are converted to jiffies by either multiplying
389 * the input value by a factor or dividing it with a factor and
390 * handling any 32-bit overflows as for msecs_to_jiffies.
391 *
392 * usecs_to_jiffies() checks for the passed in value being a constant
393 * via __builtin_constant_p() allowing gcc to eliminate most of the
394 * code, __usecs_to_jiffies() is called if the value passed does not
395 * allow constant folding and the actual conversion must be done at
396 * runtime.
397 * the HZ range specific helpers _usecs_to_jiffies() are called both
398 * directly here and from __msecs_to_jiffies() in the case where
399 * constant folding is not possible.
400 */
Denys Vlasenkoaccd0b92015-08-04 16:15:16 +0200401static __always_inline unsigned long usecs_to_jiffies(const unsigned int u)
Nicholas Mc Guireae60d6a2015-05-28 19:09:55 +0200402{
Nicholas Mc Guirec569a232015-05-28 19:09:56 +0200403 if (__builtin_constant_p(u)) {
404 if (u > jiffies_to_usecs(MAX_JIFFY_OFFSET))
405 return MAX_JIFFY_OFFSET;
406 return _usecs_to_jiffies(u);
407 } else {
408 return __usecs_to_jiffies(u);
409 }
Nicholas Mc Guireae60d6a2015-05-28 19:09:55 +0200410}
411
Baolin Wang9ca30852015-07-29 20:18:31 +0800412extern unsigned long timespec64_to_jiffies(const struct timespec64 *value);
413extern void jiffies_to_timespec64(const unsigned long jiffies,
414 struct timespec64 *value);
415static inline unsigned long timespec_to_jiffies(const struct timespec *value)
416{
417 struct timespec64 ts = timespec_to_timespec64(*value);
418
419 return timespec64_to_jiffies(&ts);
420}
421
422static inline void jiffies_to_timespec(const unsigned long jiffies,
423 struct timespec *value)
424{
425 struct timespec64 ts;
426
427 jiffies_to_timespec64(jiffies, &ts);
428 *value = timespec64_to_timespec(ts);
429}
430
Ingo Molnar8b9365d2007-02-16 01:27:27 -0800431extern unsigned long timeval_to_jiffies(const struct timeval *value);
432extern void jiffies_to_timeval(const unsigned long jiffies,
433 struct timeval *value);
Eric Dumazeta399a802012-08-08 21:13:53 +0000434
hankcbbc7192011-09-20 13:53:39 -0700435extern clock_t jiffies_to_clock_t(unsigned long x);
Eric Dumazeta399a802012-08-08 21:13:53 +0000436static inline clock_t jiffies_delta_to_clock_t(long delta)
437{
438 return jiffies_to_clock_t(max(0L, delta));
439}
440
Ingo Molnar8b9365d2007-02-16 01:27:27 -0800441extern unsigned long clock_t_to_jiffies(unsigned long x);
442extern u64 jiffies_64_to_clock_t(u64 x);
443extern u64 nsec_to_clock_t(u64 x);
Venkatesh Pallipadia1dabb62010-12-21 17:09:01 -0800444extern u64 nsecs_to_jiffies64(u64 n);
Hidetoshi Setob7b20df92009-11-26 14:49:27 +0900445extern unsigned long nsecs_to_jiffies(u64 n);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446
Ingo Molnar8b9365d2007-02-16 01:27:27 -0800447#define TIMESTAMP_SIZE 30
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448
449#endif