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, 3 insertions, 0 deletions

diff --git a/include/linux/sysrq.h b/include/linux/sysrq.h
index 387fa7d05c98..7faf933cced7 100644
--- a/include/linux/sysrq.h
+++ b/include/linux/sysrq.h
@@ -17,6 +17,9 @@
 #include <linux/errno.h>
 #include <linux/types.h>
 
+/* Enable/disable SYSRQ support by default (0==no, 1==yes). */
+#define SYSRQ_DEFAULT_ENABLE    1
+
 /* Possible values of bitmask for enabling sysrq functions */
 /* 0x0001 is reserved for enable everything */
 #define SYSRQ_ENABLE_LOG        0x0002