timekeeping: create arch_gettimeoffset infrastructure
commit7d27558c4138ac6b3684dea35c2f4379b940a7dd
authorjohn stultz <johnstul@us.ibm.com>
Fri, 1 May 2009 20:10:26 +0000 (1 13:10 -0700)
committerThomas Gleixner <tglx@linutronix.de>
Sat, 2 May 2009 09:45:15 +0000 (2 11:45 +0200)
treec10f5cee4dda1e6bc7977d016db020377f97feab
parenta25cbd045a2ffc42787d4dbcbb9c7118f5f42732
timekeeping: create arch_gettimeoffset infrastructure

Some arches don't supply their own clocksource. This is mainly the
case in architectures that get their inter-tick times by reading the
counter on their interval timer.  Since these timers wrap every tick,
they're not really useful as clocksources.  Wrapping them to act like
one is possible but not very efficient. So we provide a callout these
arches can implement for use with the jiffies clocksource to provide
finer then tick granular time.

[ Impact: ease the migration to generic time keeping ]

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
include/linux/time.h
kernel/time/timekeeping.c