[KTIME]: Introduce ktime_sub_ns and ktime_sub_us

First user will be the DCCP transport networking protocol.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Arnaldo Carvalho de Melo 2007-08-19 17:16:05 -07:00 committed by David S. Miller
parent e7a81c6d62
commit a272378d11
2 changed files with 45 additions and 0 deletions

View file

@ -102,6 +102,13 @@ static inline ktime_t ktime_set(const long secs, const unsigned long nsecs)
#define ktime_add_ns(kt, nsval) \
({ (ktime_t){ .tv64 = (kt).tv64 + (nsval) }; })
/*
* Subtract a scalar nanosecod from a ktime_t variable
* res = kt - nsval:
*/
#define ktime_sub_ns(kt, nsval) \
({ (ktime_t){ .tv64 = (kt).tv64 - (nsval) }; })
/* convert a timespec to ktime_t format: */
static inline ktime_t timespec_to_ktime(struct timespec ts)
{
@ -199,6 +206,15 @@ static inline ktime_t ktime_add(const ktime_t add1, const ktime_t add2)
*/
extern ktime_t ktime_add_ns(const ktime_t kt, u64 nsec);
/**
* ktime_sub_ns - Subtract a scalar nanoseconds value from a ktime_t variable
* @kt: minuend
* @nsec: the scalar nsec value to subtract
*
* Returns the subtraction of @nsec from @kt in ktime_t format
*/
extern ktime_t ktime_sub_ns(const ktime_t kt, u64 nsec);
/**
* timespec_to_ktime - convert a timespec to ktime_t format
* @ts: the timespec variable to convert
@ -289,6 +305,11 @@ static inline ktime_t ktime_add_us(const ktime_t kt, const u64 usec)
return ktime_add_ns(kt, usec * 1000);
}
static inline ktime_t ktime_sub_us(const ktime_t kt, const u64 usec)
{
return ktime_sub_ns(kt, usec * 1000);
}
/*
* The resolution of the clocks. The resolution value is returned in
* the clock_getres() system call to give application programmers an

View file

@ -277,6 +277,30 @@ ktime_t ktime_add_ns(const ktime_t kt, u64 nsec)
}
EXPORT_SYMBOL_GPL(ktime_add_ns);
/**
* ktime_sub_ns - Subtract a scalar nanoseconds value from a ktime_t variable
* @kt: minuend
* @nsec: the scalar nsec value to subtract
*
* Returns the subtraction of @nsec from @kt in ktime_t format
*/
ktime_t ktime_sub_ns(const ktime_t kt, u64 nsec)
{
ktime_t tmp;
if (likely(nsec < NSEC_PER_SEC)) {
tmp.tv64 = nsec;
} else {
unsigned long rem = do_div(nsec, NSEC_PER_SEC);
tmp = ktime_set((long)nsec, rem);
}
return ktime_sub(kt, tmp);
}
EXPORT_SYMBOL_GPL(ktime_sub_ns);
# endif /* !CONFIG_KTIME_SCALAR */
/*