virtio-scsi: enable MSI-X support

While virtio-scsi does support multiqueue, the default number of
interrupt vectors is not enough to actually enable usage of
multiple queues in the driver; this is because with only 2
vectors the driver will not be able to use a separate
interrupt for each request queue.  Derive the desired number
of vectors from the number of request queues.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2012-07-27 14:38:03 +02:00
parent 3f910904ec
commit 4c205d0cb1
1 changed files with 4 additions and 2 deletions

View File

@ -1023,7 +1023,9 @@ static int virtio_scsi_init_pci(PCIDevice *pci_dev)
return -EINVAL;
}
vdev->nvectors = proxy->nvectors;
vdev->nvectors = proxy->nvectors == DEV_NVECTORS_UNSPECIFIED
? proxy->scsi.num_queues + 3
: proxy->nvectors;
virtio_init_pci(proxy, vdev);
/* make the actual value visible */
@ -1041,7 +1043,7 @@ static int virtio_scsi_exit_pci(PCIDevice *pci_dev)
static Property virtio_scsi_properties[] = {
DEFINE_PROP_BIT("ioeventfd", VirtIOPCIProxy, flags, VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, true),
DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors, 2),
DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors, DEV_NVECTORS_UNSPECIFIED),
DEFINE_VIRTIO_SCSI_PROPERTIES(VirtIOPCIProxy, host_features, scsi),
DEFINE_PROP_END_OF_LIST(),
};