tree 62e0ba3e3b031ded8187b1c37681015ec920ebe2
parent e59717550e5cf0e7159c5b7af1d1ead35fef49dd
author Michael S. Tsirkin <mst@redhat.com> 1334159395 +0300
committer Marcelo Tosatti <mtosatti@redhat.com> 1334619398 -0300

KVM: dont clear TMR on EOI

Intel spec says that TMR needs to be set/cleared
when IRR is set, but kvm also clears it on  EOI.

I did some tests on a real (AMD based) system,
and I see same TMR values both before
and after EOI, so I think it's a minor bug in kvm.

This patch fixes TMR to be set/cleared on IRR set
only as per spec.

And now that we don't clear TMR, we can save
an atomic read of TMR on EOI that's not propagated
to ioapic, by checking whether ioapic needs
a specific vector first and calculating
the mode afterwards.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>