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Subject[PATCH 3/6] kvm,lapic: Justify use of swait_activate()
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A comment might serve future readers.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
arch/x86/kvm/lapic.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 589dcc117086..fb8be28c7093 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1326,6 +1326,12 @@ static void apic_timer_expired(struct kvm_lapic *apic)
atomic_inc(&apic->lapic_timer.pending);
kvm_set_pending_timer(vcpu);

+ /*
+ * The above kvm_set_pending_timer implies a wmb
+ * which pairs with the swaiter side. Either way,
+ * the atomic_inc() is also serialized so using
+ * swait_active() is safe.
+ */
if (swait_active(q))
swake_up(q);

--
2.12.0
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