/*
* include/linux/ktime.h
*
* ktime_t - nanosecond-resolution time format.
*
* Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
* Copyright(C) 2005, Red Hat, Inc., Ingo Molnar
*
* data type definitions, declarations, prototypes and macros.
*
* Started by: Thomas Gleixner and Ingo Molnar
*
* Credits:
*
* Roman Zippel provided the ideas and primary code snippets of
* the ktime_t union and further simplifications of the original
* code.
*
* For licencing details see kernel-base/COPYING
*/
#ifndef _LINUX_KTIME_H
#define _LINUX_KTIME_H
#include <linux/time.h>
#include <linux/jiffies.h>
/* Nanosecond scalar representation for kernel time values */
typedef s64 ktime_t;
/**
* ktime_set - Set a ktime_t variable from a seconds/nanoseconds value
* @secs: seconds to set
* @nsecs: nanoseconds to set
*
* Return: The ktime_t representation of the value.
*/
static inline ktime_t ktime_set(const s64 secs, const unsigned long nsecs)
{
if (unlikely(secs >= KTIME_SEC_MAX))
return KTIME_MAX;
return secs * NSEC_PER_SEC + (s64)nsecs;
}
/* Subtract two ktime_t variables. rem = lhs -rhs: */
#define ktime_sub(lhs, rhs) ((lhs) - (rhs))
/* Add two ktime_t variables. res = lhs + rhs: */
#define ktime_add(lhs, rhs) ((lhs) + (rhs))
/*
* Same as ktime_add(), but avoids undefined behaviour on overflow; however,
* this means that you must check the result for overflow yourself.
*/
#define ktime_add_unsafe(lhs, rhs) ((u64) (lhs) + (rhs))
/*
* Add a ktime_t variable and a scalar nanosecond value.
* res = kt + nsval:
*/
#define ktime_add_ns(kt, nsval) ((kt) + (nsval))
/*
* Subtract a scalar nanosecod from a ktime_t variable
* res = kt - nsval:
*/
#define ktime_sub_ns(kt, nsval) ((kt) - (nsval))
/* convert a timespec to ktime_t format: */
static inline ktime_t timespec_to_ktime(struct timespec ts)
{
return ktime_set(ts.tv_sec, ts.tv_nsec);
}
/* convert a timespec64 to ktime_t format: */
static inline ktime_t timespec64_to_ktime(struct timespec64 ts)
{
return ktime_set(ts.tv_sec, ts.tv_nsec);
}
/* convert a timeval to ktime_t format: */
static inline ktime_t timeval_to_ktime(struct timeval tv)
{
return ktime_set(tv.tv_sec, tv.tv_usec * NSEC_PER_USEC);
}
/* Map the ktime_t to timespec conversion to ns_to_timespec function */
#define ktime_to_timespec(kt) ns_to_timespec((kt))
/* Map the ktime_t to timespec conversion to ns_to_timespec function */
#define ktime_to_timespec64(kt) ns_to_timespec64((kt))
/* Map the ktime_t to timeval conversion to ns_to_timeval function */
#define ktime_to_timeval(kt) ns_to_timeval((kt))
/* Convert ktime_t to nanoseconds */
static inline s64 ktime_to_ns(const ktime_t kt)
{
return kt;
}
/**
* ktime_compare - Compares two ktime_t variables for less, greater or equal
* @cmp1: comparable1
* @cmp2: comparable2
*
* Return: ...
* cmp1 < cmp2: return <0
* cmp1 == cmp2: return 0
* cmp1 > cmp2: return >0
*/
static inline int ktime_compare(const ktime_t cmp1, const ktime_t cmp2)
{
if (cmp1 < cmp2)
return -1;
if (cmp1 > cmp2)
return 1;
return 0;
}
/**
* ktime_after - Compare if a ktime_t value is bigger than another one.
* @cmp1: comparable1
* @cmp2: comparable2
*
* Return: true if cmp1 happened after cmp2.
*/
static inline bool ktime_after(const ktime_t cmp1, const ktime_t cmp2)
{
return ktime_compare(cmp1, cmp2) > 0;
}
/**
* ktime_before - Compare if a ktime_t value is smaller than another one.
* @cmp1: comparable1
* @cmp2: comparable2
*
* Return: true if cmp1 happened before cmp2.
*/
static inline bool ktime_before(const ktime_t cmp1, const ktime_t cmp2)
{
return ktime_compare(cmp1, cmp2) < 0;
}
#if BITS_PER_LONG < 64
extern s64 __ktime_divns(const ktime_t kt, s64 div);
static inline s64 ktime_divns(const ktime_t kt, s64 div)
{
/*
* Negative divisors could cause an inf loop,
* so bug out here.
*/
BUG_ON(div < 0);
if (__builtin_constant_p(div) && !(div >> 32)) {
s64 ns = kt;
u64 tmp = ns < 0 ? -ns : ns;
do_div(tmp, div);
return ns < 0 ? -tmp : tmp;
} else {
return __ktime_divns(kt, div);
}
}
#else /* BITS_PER_LONG < 64 */
static inline s64 ktime_divns(const ktime_t kt, s64 div)
{
/*
* 32-bit implementation cannot handle negative divisors,
* so catch them on 64bit as well.
*/
WARN_ON(div < 0);
return kt / div;
}
#endif
static inline s64 ktime_to_us(const ktime_t kt)
{
return ktime_divns(kt, NSEC_PER_USEC);
}
static inline s64 ktime_to_ms(const ktime_t kt)
{
return ktime_divns(kt, NSEC_PER_MSEC);
}
static inline s64 ktime_us_delta(const ktime_t later, const ktime_t earlier)
{
return ktime_to_us(ktime_sub(later, earlier));
}
static inline s64 ktime_ms_delta(const ktime_t later, const ktime_t earlier)
{
return ktime_to_ms(ktime_sub(later, earlier));
}
static inline ktime_t ktime_add_us(const ktime_t kt, const u64 usec)
{
return ktime_add_ns(kt, usec * NSEC_PER_USEC);
}
static inline ktime_t ktime_add_ms(const ktime_t kt, const u64 msec)
{
return ktime_add_ns(kt, msec * NSEC_PER_MSEC);
}
static inline ktime_t ktime_sub_us(const ktime_t kt, const u64 usec)
{
return ktime_sub_ns(kt, usec * NSEC_PER_USEC);
}
static inline ktime_t ktime_sub_ms(const ktime_t kt, const u64 msec)
{
return ktime_sub_ns(kt, msec * NSEC_PER_MSEC);
}
extern ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs);
/**
* ktime_to_timespec_cond - convert a ktime_t variable to timespec
* format only if the variable contains data
* @kt: the ktime_t variable to convert
* @ts: the timespec variable to store the result in
*
* Return: %true if there was a successful conversion, %false if kt was 0.
*/
static inline __must_check bool ktime_to_timespec_cond(const ktime_t kt,
struct timespec *ts)
{
if (kt) {
*ts = ktime_to_timespec(kt);
return true;
} else {
return false;
}
}
/**
* ktime_to_timespec64_cond - convert a ktime_t variable to timespec64
* format only if the variable contains data
* @kt: the ktime_t variable to convert
* @ts: the timespec variable to store the result in
*
* Return: %true if there was a successful conversion, %false if kt was 0.
*/
static inline __must_check bool ktime_to_timespec64_cond(const ktime_t kt,
struct timespec64 *ts)
{
if (kt) {
*ts = ktime_to_timespec64(kt);
return true;
} else {
return false;
}
}
/*
* The resolution of the clocks. The resolution value is returned in
* the clock_getres() system call to give application programmers an
* idea of the (in)accuracy of timers. Timer values are rounded up to
* this resolution values.
*/
#define LOW_RES_NSEC TICK_NSEC
#define KTIME_LOW_RES (LOW_RES_NSEC)
static inline ktime_t ns_to_ktime(u64 ns)
{
return ns;
}
static inline ktime_t ms_to_ktime(u64 ms)
{
return ms * NSEC_PER_MSEC;
}
# include <linux/timekeeping.h>
# include <linux/timekeeping32.h>
#endif
