| From ae83b56a56f8d9643dedbee86b457fa1c5d42f59 Mon Sep 17 00:00:00 2001 |
| From: Xunlei Pang <xlpang@redhat.com> |
| Date: Wed, 10 May 2017 21:03:37 +0800 |
| Subject: sched/deadline: Zero out positive runtime after throttling constrained tasks |
| |
| From: Xunlei Pang <xlpang@redhat.com> |
| |
| 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. |
| |
| Signed-off-by: Xunlei Pang <xlpang@redhat.com> |
| Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> |
| Acked-by: Daniel Bristot de Oliveira <bristot@redhat.com> |
| Cc: Juri Lelli <juri.lelli@arm.com> |
| Cc: Linus Torvalds <torvalds@linux-foundation.org> |
| Cc: Luca Abeni <luca.abeni@santannapisa.it> |
| Cc: Mike Galbraith <efault@gmx.de> |
| Cc: Peter Zijlstra <peterz@infradead.org> |
| Cc: Steven Rostedt <rostedt@goodmis.org> |
| Cc: Thomas Gleixner <tglx@linutronix.de> |
| Fixes: df8eac8cafce ("sched/deadline: Throttle a constrained deadline task activated after the deadline) |
| Link: http://lkml.kernel.org/r/1494421417-27550-1-git-send-email-xlpang@redhat.com |
| Signed-off-by: Ingo Molnar <mingo@kernel.org> |
| Cc: Ben Hutchings <ben.hutchings@codethink.co.uk> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| kernel/sched/deadline.c | 2 ++ |
| 1 file changed, 2 insertions(+) |
| |
| --- a/kernel/sched/deadline.c |
| +++ b/kernel/sched/deadline.c |
| @@ -732,6 +732,8 @@ 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; |
| } |
| } |
| |
