[tip:sched/core] sched: Change position of resched_cpu() in load_balance()

[tip-bot for Joonsoo Kim]

Commit-ID:  f1cd0858100c67273f2c74344e0c464344c4a982
Gitweb:     http://git.kernel.org/tip/f1cd0858100c67273f2c74344e0c464344c4a982
Author:     Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
AuthorDate: Tue, 23 Apr 2013 17:27:37 +0900
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 24 Apr 2013 08:52:43 +0200

sched: Change position of resched_cpu() in load_balance()

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>
Tested-by: Jason Low <jason.low2@xxxxxx>
Acked-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Srivatsa Vaddagiri <vatsa@xxxxxxxxxxxxxxxxxx>
Cc: Davidlohr Bueso <davidlohr.bueso@xxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1366705662-3587-2-git-send-email-iamjoonsoo.kim@xxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 kernel/sched/fair.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 1c97735..25aaf93 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5080,17 +5080,17 @@ 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
--
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