tree addbfb1207d816b1e1f5e4ab75f95a08c7b15202
parent 464b75273f64be7c81fee975bd6ca9593df3427b
author Peter Zijlstra <a.p.zijlstra@chello.nl> 1224839176 +0200
committer Ingo Molnar <mingo@elte.hu> 1224845463 +0200

sched: virtual time buddy preemption

Since we moved wakeup preemption back to virtual time, it makes sense to move
the buddy stuff back as well. The purpose of the buddy scheduling is to allow
a quickly scheduling pair of tasks to run away from the group as far as a
regular busy task would be allowed under wakeup preemption.

This has the advantage that the pair can ping-pong for a while, enjoying
cache-hotness. Without buddy scheduling other tasks would interleave destroying
the cache.

Also, it saves a word in cfs_rq.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>