[PATCH 4.9 16/38] KVM: lapic: Split out x2apic ldr calculation

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dr. David Alan Gilbert <dgilbert@xxxxxxxxxx>

commit e872fa94662d0644057c7c80b3071bdb9249e5ab upstream.

Split out the ldr calculation from kvm_apic_set_x2apic_id
since we're about to reuse it in the following patch.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 arch/x86/kvm/lapic.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -246,9 +246,14 @@ static inline void kvm_apic_set_ldr(stru
 	recalculate_apic_map(apic->vcpu->kvm);
 }
 
+static inline u32 kvm_apic_calc_x2apic_ldr(u32 id)
+{
+	return ((id >> 4) << 16) | (1 << (id & 0xf));
+}
+
 static inline void kvm_apic_set_x2apic_id(struct kvm_lapic *apic, u32 id)
 {
-	u32 ldr = ((id >> 4) << 16) | (1 << (id & 0xf));
+	u32 ldr = kvm_apic_calc_x2apic_ldr(id);
 
 	kvm_lapic_set_reg(apic, APIC_ID, id);
 	kvm_lapic_set_reg(apic, APIC_LDR, ldr);