sched: align rq to cacheline boundary

Align the per cpu runqueue to the cacheline boundary.  This will minimize
the number of cachelines touched during remote wakeup.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Ravikiran G Thirumalai <kiran@scalex86.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/sched.c

@@ -304,7 +304,7 @@ struct rq {
 	struct lock_class_key rq_lock_key;
 };
 
-static DEFINE_PER_CPU(struct rq, runqueues);
+static DEFINE_PER_CPU(struct rq, runqueues) ____cacheline_aligned_in_smp;
 
 static inline int cpu_of(struct rq *rq)
 {