From: Keir Fraser <keir.fraser@citrix.com>
Date: Tue, 29 Jul 2008 09:42:30 +0000 (+0100)
Subject: x86: reprogram LAPIC timer in pit_broadcast_exit
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~14165^2~94
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/success//%22http:/www.example.com/cgi/success/?a=commitdiff_plain;h=5c23498926626385ea51a774ea1a5d0e5c35ab77;p=xen.git

x86: reprogram LAPIC timer in pit_broadcast_exit

Thus to remove possible timer expiring delay caused by deep C state
LAPIC timer stopping.

Signed-off-by: Wei Gang <gang.wei@intel.com>
---

diff --git a/xen/arch/x86/time.c b/xen/arch/x86/time.c
index 570a630884..1c73840b61 100644
--- a/xen/arch/x86/time.c
+++ b/xen/arch/x86/time.c
@@ -1135,7 +1135,10 @@ void pit_broadcast_enter(void)
 
 void pit_broadcast_exit(void)
 {
-    cpu_clear(smp_processor_id(), pit_broadcast_mask);
+    int cpu = smp_processor_id();
+
+    if ( cpu_test_and_clear(cpu, pit_broadcast_mask) )
+        reprogram_timer(per_cpu(timer_deadline, cpu));
 }
 
 int pit_broadcast_is_available(void)