Patch "sched/deadline: Zero out positive runtime after throttling constrained tasks" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

sched/deadline: Zero out positive runtime after throttling constrained tasks

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
sched-deadline-zero-out-positive-runtime-after-throttling-constrained-tasks.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Xunlei Pang <[email protected]>
Date: Wed, 10 May 2017 21:03:37 +0800
Subject: sched/deadline: Zero out positive runtime after throttling constrained tasks

From: Xunlei Pang <[email protected]>

commit ae83b56a56f8d9643dedbee86b457fa1c5d42f59 upstream.

When a contrained task is throttled by dl_check_constrained_dl(), it may carry the remaining positive runtime, as a result when dl_task_timer() fires and calls replenish_dl_entity(), it will not be replenished correctly due to the positive dl_se->runtime.

This patch assigns its runtime to 0 if positive after throttling.

---
 kernel/sched/deadline.c |    2 ++
 1 file changed, 2 insertions(+)

@@ -723,6 +723,8 @@ static inline void dl_check_constrained_
 		if (unlikely(dl_se->dl_boosted || !start_dl_timer(p)))
 			return;
 		dl_se->dl_throttled = 1;
+		if (dl_se->runtime > 0)
+			dl_se->runtime = 0;
 	}
 }
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/sched-deadline-zero-out-positive-runtime-after-throttling-constrained-tasks.patch