[PATCH 03/12] sched: Fix task_hot() test order

[Peter Zijlstra <a.p.zijlstra@chello.nl>]

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Make sure not to access sched_fair fields before verifying it is
indeed a sched_fair task.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: stable@kernel.org
---
 kernel/sched.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Index: linux-2.6/kernel/sched.c
===================================================================
--- linux-2.6.orig/kernel/sched.c
+++ linux-2.6/kernel/sched.c
@@ -2044,6 +2044,9 @@ task_hot(struct task_struct *p, u64 now,
 {
 	s64 delta;
 
+	if (p->sched_class != &fair_sched_class)
+		return 0;
+
 	/*
 	 * Buddy candidates are cache hot:
 	 */
@@ -2052,9 +2055,6 @@ task_hot(struct task_struct *p, u64 now,
 			 &p->se == cfs_rq_of(&p->se)->last))
 		return 1;
 
-	if (p->sched_class != &fair_sched_class)
-		return 0;
-
 	if (sysctl_sched_migration_cost == -1)
 		return 1;
 	if (sysctl_sched_migration_cost == 0)

--