From: Meng Xu <mengxu@cis.upenn.edu>
Date: Sat, 22 Oct 2016 02:12:02 +0000 (-0400)
Subject: xen: rtds: always clear the flag when replenishing a depleted vcpu
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~148
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=1b843b2097e89d0fae18123cde88da9d167d9a0c;p=xen.git

xen: rtds: always clear the flag when replenishing a depleted vcpu

We should clear the __RTDS_depleted bit once a VCPU budget is replenished.
Because repl_timer_handler may be called after rt_schedule
but before rt_context_saved, the VCPU may be not on CPU or on queue
when the VCPU is the middle of context switch

Signed-off-by: Meng Xu <mengxu@cis.upenn.edu>
Acked-by: Dario Faggioli <dario.faggioli@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
---

diff --git a/xen/common/sched_rt.c b/xen/common/sched_rt.c
index d95f79818f..d61804a1ce 100644
--- a/xen/common/sched_rt.c
+++ b/xen/common/sched_rt.c
@@ -1480,8 +1480,8 @@ static void repl_timer_handler(void *data){
             if ( svc->cur_deadline > next_on_runq->cur_deadline )
                 runq_tickle(ops, next_on_runq);
         }
-        else if ( vcpu_on_q(svc) &&
-                  __test_and_clear_bit(__RTDS_depleted, &svc->flags) )
+        else if ( __test_and_clear_bit(__RTDS_depleted, &svc->flags) &&
+                  vcpu_on_q(svc) )
             runq_tickle(ops, svc);
 
         list_del(&svc->replq_elem);