- introduce ktime_t: nanosecond-resolution time format.

- eliminate the plain s64 scalar type, and always use the union.
  This simplifies the arithmetics. Idea from Roman Zippel.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>