From: Davidlohr Bueso <dave@stgolabs.net>
Date: Wed, 13 Sep 2017 20:08:20 +0000 (-0700)
Subject: kvm,lapic: Justify use of swait_active()
X-Git-Tag: v4.14-rc1~10^2~7
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=cc1b46803a671047be22f7832ef4a2bb3f63dd94;p=platform%2Fkernel%2Flinux-exynos.git

kvm,lapic: Justify use of swait_active()

A comment might serve future readers.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index aaf10b6..69c5612 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);