Latency: the radical approach

Ingo Molnar's realtime preemption patch
Turn all spinlocks into semaphores
All kernel code becomes preemptible

Move interrupt handling to kernel threads
Priorities of interrupts can be adjusted
Interrupt handlers are preemptible

Change some locking methods
Per-CPU variables
Read-copy-update

This is a huge, intrusive change
Expect a major debate before it's merged
if ever
Could be a motivation for 2.7