KVM: change the way how lowest priority vcpu is calculated
The new way does not require additional loop over vcpus to calculate
the one with lowest priority as one is chosen during delivery bitmap
construction.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
index e43701c..f5e059b 100644
--- a/virt/kvm/irq_comm.c
+++ b/virt/kvm/irq_comm.c
@@ -47,7 +47,7 @@
int dest_id, int dest_mode, bool low_prio, int short_hand,
unsigned long *deliver_bitmask)
{
- int i;
+ int i, lowest = -1;
struct kvm_vcpu *vcpu;
if (dest_mode == 0 && dest_id == 0xff && low_prio)
@@ -64,15 +64,18 @@
dest_mode))
continue;
- __set_bit(i, deliver_bitmask);
+ if (!low_prio) {
+ __set_bit(i, deliver_bitmask);
+ } else {
+ if (lowest < 0)
+ lowest = i;
+ if (kvm_apic_compare_prio(vcpu, kvm->vcpus[lowest]) < 0)
+ lowest = i;
+ }
}
- if (low_prio) {
- vcpu = kvm_get_lowest_prio_vcpu(kvm, 0, deliver_bitmask);
- bitmap_zero(deliver_bitmask, KVM_MAX_VCPUS);
- if (vcpu)
- __set_bit(vcpu->vcpu_id, deliver_bitmask);
- }
+ if (lowest != -1)
+ __set_bit(lowest, deliver_bitmask);
}
static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,