[PATCH 3/7] kvm,lapic: Justify use of swait_activate()

From: Davidlohr Bueso
Date: Wed Sep 13 2017 - 16:10:41 EST


A comment might serve future readers.

Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
---
arch/x86/kvm/lapic.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index aaf10b6f5380..69c5612be786 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1324,6 +1324,10 @@ static void apic_timer_expired(struct kvm_lapic *apic)
atomic_inc(&apic->lapic_timer.pending);
kvm_set_pending_timer(vcpu);

+ /*
+ * For x86, the atomic_inc() is serialized, thus
+ * using swait_active() is safe.
+ */
if (swait_active(q))
swake_up(q);

--
2.12.0