KVM: x86: Simplify kvm timer handler

The vcpu reference of a kvm_timer can't become NULL while the timer is
valid, so drop this redundant test. This also makes it pointless to
carry a separate __kvm_timer_fn, fold it into kvm_timer_fn.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

arch/x86/kvm/timer.c

@@ -18,9 +18,10 @@
 #include <linux/atomic.h>
 #include "kvm_timer.h"
 
-static int __kvm_timer_fn(struct kvm_vcpu *vcpu, struct kvm_timer *ktimer)
+enum hrtimer_restart kvm_timer_fn(struct hrtimer *data)
 {
-	int restart_timer = 0;
+	struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer);
+	struct kvm_vcpu *vcpu = ktimer->vcpu;
 	wait_queue_head_t *q = &vcpu->wq;
 
 	/*
@@ -40,26 +41,7 @@ static int __kvm_timer_fn(struct kvm_vcpu *vcpu, struct kvm_timer *ktimer)
 
 	if (ktimer->t_ops->is_periodic(ktimer)) {
 		hrtimer_add_expires_ns(&ktimer->timer, ktimer->period);
-		restart_timer = 1;
-	}
-
-	return restart_timer;
-}
-
-enum hrtimer_restart kvm_timer_fn(struct hrtimer *data)
-{
-	int restart_timer;
-	struct kvm_vcpu *vcpu;
-	struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer);
-
-	vcpu = ktimer->vcpu;
-	if (!vcpu)
-		return HRTIMER_NORESTART;
-
-	restart_timer = __kvm_timer_fn(vcpu, ktimer);
-	if (restart_timer)
 		return HRTIMER_RESTART;
-	else
+	} else
 		return HRTIMER_NORESTART;
 }
-