Commit a272378d authored by Arnaldo Carvalho de Melo's avatar Arnaldo Carvalho de Melo Committed by David S. Miller
Browse files

[KTIME]: Introduce ktime_sub_ns and ktime_sub_us 



First user will be the DCCP transport networking protocol.

Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e7a81c6d

include/linux/ktime.h

+21 −0
Original line number Diff line number Diff line
@@ -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

kernel/hrtimer.c

+24 −0
Original line number Diff line number Diff line
@@ -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 */



/*