timekeeping: Increase granularity of read_persistent_clock()

The persistent clock of some architectures (e.g. s390) have a
better granularity than seconds. To reduce the delta between the
host clock and the guest clock in a virtualized system change the 
read_persistent_clock function to return a struct timespec.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Daniel Walker <dwalker@fifo99.com>
LKML-Reference: <20090814134811.013873340@de.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 2 insertions, 3 deletions

diff --git a/arch/xtensa/kernel/time.c b/arch/xtensa/kernel/time.c
index 8848120d291b..19085ff0484a 100644
--- a/arch/xtensa/kernel/time.c
+++ b/arch/xtensa/kernel/time.c
@@ -59,9 +59,8 @@ static struct irqaction timer_irqaction = {
 
 void __init time_init(void)
 {
-        xtime.tv_nsec = 0;
-        xtime.tv_sec = read_persistent_clock();
-
+        /* FIXME: xtime&wall_to_monotonic are set in timekeeping_init. */
+        read_persistent_clock(&xtime);
         set_normalized_timespec(&wall_to_monotonic,
                 -xtime.tv_sec, -xtime.tv_nsec);