sched: Unthrottle rt runqueues in __disable_runtime()

migrate_tasks() uses _pick_next_task_rt() to get tasks from the
real-time runqueues to be migrated. When rt_rq is throttled
_pick_next_task_rt() won't return anything, in which case
migrate_tasks() can't move all threads over and gets stuck in an
infinite loop.

Instead unthrottle rt runqueues before migrating tasks.

Additionally: move unthrottle_offline_cfs_rqs() to rq_offline_fair()

Signed-off-by: Peter Boonstoppel <pboonstoppel@nvidia.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Turner <pjt@google.com>
Link: http://lkml.kernel.org/r/5FBF8E85CA34454794F0F7ECBA79798F379D3648B7@HQMAIL04.nvidia.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 944cb68420e9..e0b7ba9c040f 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -691,6 +691,7 @@ balanced:
                  * runtime - in which case borrowing doesn't make sense.
                  */
                 rt_rq->rt_runtime = RUNTIME_INF;
+                rt_rq->rt_throttled = 0;
                 raw_spin_unlock(&rt_rq->rt_runtime_lock);
                 raw_spin_unlock(&rt_b->rt_runtime_lock);
         }