2.6.35-longterm review patch.  If anyone has any objections, please let me know.

------------------
Commit: ef8002f6848236de5adc613063ebeabddea8a6fb upstream

This patch adds a check in task_hot to return if the task has SCHED_IDLE
policy. SCHED_IDLE tasks have very low weight, and when run with regular
workloads, are typically scheduled many milliseconds apart. There is no
need to consider these tasks hot for load balancing.

Signed-off-by: Nikhil Rao <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Signed-off-by: Andi Kleen <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Mike Galbraith <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 kernel/sched.c |    3 +++
 1 file changed, 3 insertions(+)

Index: linux-2.6.35.y/kernel/sched.c
===================================================================
--- linux-2.6.35.y.orig/kernel/sched.c  2011-03-29 23:02:59.968300981 -0700
+++ linux-2.6.35.y/kernel/sched.c       2011-03-29 23:55:02.689398361 -0700
@@ -1972,6 +1972,9 @@
        if (p->sched_class != &fair_sched_class)
                return 0;
 
+       if (unlikely(p->policy == SCHED_IDLE))
+               return 0;
+
        /*
         * Buddy candidates are cache hot:
         */

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