[PATCH 1/8] sched: change position of resched_cpu() in load_balance()

From: Joonsoo Kim
Date: Thu Feb 14 2013 - 00:49:27 EST


cur_ld_moved is reset if env.flags hit LBF_NEED_BREAK.
So, there is possibility that we miss doing resched_cpu().
Correct it as changing position of resched_cpu()
before checking LBF_NEED_BREAK.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 81fa536..6f72851 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5070,17 +5070,17 @@ more_balance:
double_rq_unlock(env.dst_rq, busiest);
local_irq_restore(flags);

- if (env.flags & LBF_NEED_BREAK) {
- env.flags &= ~LBF_NEED_BREAK;
- goto more_balance;
- }
-
/*
* some other cpu did the load balance for us.
*/
if (cur_ld_moved && env.dst_cpu != smp_processor_id())
resched_cpu(env.dst_cpu);

+ if (env.flags & LBF_NEED_BREAK) {
+ env.flags &= ~LBF_NEED_BREAK;
+ goto more_balance;
+ }
+
/*
* Revisit (affine) tasks on src_cpu that couldn't be moved to
* us and move them to an alternate dst_cpu in our sched_group
--
1.7.9.5

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