A PCI device can be associated with a specific NUMA node. Later, when
a guest is pinned to one NUMA node the PCI device can be assigned on
different NUMA node. This makes DMA transfers travel across nodes and
thus results in suboptimal performance. We should expose the NUMA node
locality for PCI devices so management applications can make better
decisions.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This includes adding it to the nodedev parser and formatter, docs, and
test.
An example of the new iommuGroup element that is a part of the output
from "virsh nodedev-dumpxml" (virNodeDeviceGetXMLDesc()):
<device>
<name>pci_0000_02_00_1</name>
<capability type='pci'>
...
<iommuGroup number='12'>
<address domain='0x0000' bus='0x02' slot='0x00' function='0x0'/>
<address domain='0x0000' bus='0x02' slot='0x00' function='0x1'/>
</iommuGroup>
</capability>
</device>
