Merge 'Linux v3.0' into Litmus

Some notes:
* Litmus^RT scheduling class is the topmost scheduling class
  (above stop_sched_class).
* scheduler_ipi() function (e.g., in smp_reschedule_interrupt())
  may increase IPI latencies.
* Added path into schedule() to quickly re-evaluate scheduling
  decision without becoming preemptive again. This used to be
  a standard path before the removal of BKL.

Conflicts:
	Makefile
	arch/arm/kernel/calls.S
	arch/arm/kernel/smp.c
	arch/x86/include/asm/unistd_32.h
	arch/x86/kernel/smp.c
	arch/x86/kernel/syscall_table_32.S
	include/linux/hrtimer.h
	kernel/printk.c
	kernel/sched.c
	kernel/sched_fair.c

1 files changed, 6 insertions, 1 deletions

diff --git a/litmus/sched_litmus.c b/litmus/sched_litmus.c
index e6952896dc4b..cb705e7f0466 100644
--- a/litmus/sched_litmus.c
+++ b/litmus/sched_litmus.c
@@ -294,7 +294,12 @@ static int select_task_rq_litmus(struct rq *rq, struct task_struct *p,
 #endif
 
 static const struct sched_class litmus_sched_class = {
-        .next                   = &rt_sched_class,
+        /* From 34f971f6 the stop/migrate worker threads have a class on
+         * their own, which is the highest prio class. We don't support
+         * cpu-hotplug or cpu throttling. Allows Litmus to use up to 1.0
+         * CPU capacity.
+         */
+        .next                   = &stop_sched_class,
         .enqueue_task           = enqueue_task_litmus,
         .dequeue_task           = dequeue_task_litmus,
         .yield_task             = yield_task_litmus,