From mboxrd@z Thu Jan 1 00:00:00 1970 From: Davidlohr Bueso Subject: [PATCH 3/7] kvm,lapic: Justify use of swait_activate() Date: Wed, 13 Sep 2017 13:08:20 -0700 Message-ID: <20170913200824.28067-4-dave@stgolabs.net> References: <20170913200824.28067-1-dave@stgolabs.net> Cc: npiggin@gmail.com, paulmck@linux.vnet.ibm.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, dave@stgolabs.net, Davidlohr Bueso To: mingo@kernel.org, peterz@infradead.org, pbonzini@redhat.com Return-path: In-Reply-To: <20170913200824.28067-1-dave@stgolabs.net> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org A comment might serve future readers. Signed-off-by: Davidlohr Bueso --- 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