virtio_ccw: pass a cookie value to kvm hypercall
authorMichael S. Tsirkin <mst@redhat.com>
Thu, 28 Feb 2013 11:33:16 +0000 (12:33 +0100)
committerMarcelo Tosatti <mtosatti@redhat.com>
Tue, 5 Mar 2013 22:12:09 +0000 (19:12 -0300)
commit07e169335ff0570c6e67b5ccf74d793f00ab0834
treef96290e4e141305498fe5cb97a9efffc958c0d7a
parent503cd0c50ac7161eb5c3891b48b620cb0a5521cd
virtio_ccw: pass a cookie value to kvm hypercall

Lookups by channel/vq pair on host during virtio notifications might be
expensive.  Interpret hypercall return value as a cookie which host can
use to do device lookups for the next notification more efficiently.

[CH: Fix line > 80 chars]
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
drivers/s390/kvm/virtio_ccw.c