KVM: Drop useless atomic test from timer function

The current code tries to optimize the setting of
KVM_REQ_PENDING_TIMER but used atomic_inc_and_test - which always
returns true unless pending had the invalid value of -1 on entry. This
patch drops the test part preserving the original semantic but
expressing it less confusingly.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

diff --git a/arch/x86/kvm/timer.c b/arch/x86/kvm/timer.c
index 1baed41..eea4043 100644 (file)
--- a/arch/x86/kvm/timer.c
+++ b/arch/x86/kvm/timer.c
@@ -15,9 +15,9 @@ static int __kvm_timer_fn(struct kvm_vcpu *vcpu, struct kvm_timer *ktimer)
         * case anyway.
         */
        if (ktimer->reinject || !atomic_read(&ktimer->pending)) {
+               atomic_inc(&ktimer->pending);
                /* FIXME: this code should not know anything about vcpus */
-               if (!atomic_inc_and_test(&ktimer->pending))
-                       set_bit(KVM_REQ_PENDING_TIMER, &vcpu->requests);
+               set_bit(KVM_REQ_PENDING_TIMER, &vcpu->requests);
        }
 
        if (waitqueue_active(q))