Adds support for the node daemon managing SR-IOV PF and VF instances.
PFs are added to Zookeeper automatically based on the config at startup
during network configuration, and are otherwise completely static. PFs
are automatically removed from Zookeeper, along with all coresponding
VFs, should the PF phy device be removed from the configuration.
VFs are configured based on the (autocreated) VFs of each PF device,
added to Zookeeper, and then a new class instance, SRIOVVFInstance, is
used to watch them for configuration changes. This will enable the
runtime management of VF settings by the API. The set of keys ensures
that both configuration and details of the NIC can be tracked.
Most keys are self-explanatory, especially for PFs and the basic keys
for VFs. The configuration tree is also self-explanatory, being based
entirely on the options available in the `ip link set {dev} vf` command.
Two additional keys are also present: `used` and `used_by`, which will
be able to track the (boolean) state of usage, as well as the VM that
uses a given VIF. Since the VM side implementation will support both
macvtap and direct "hostdev" assignments, this will ensure that this
state can be tracked on both the VF and the VM side.
Adds configuration values for enabled flag and SR-IOV devices to the
configuration and sets up the initial SR-IOV configuration on daemon
startup (inserting the module, configuring the VF count, etc.).
Instead of exiting and trusting systemd to restart us, instead leverage
the os.execv() call to reload the process in the current PID context.
Also improves the log messages so it's very clear what's going on.
A hot reload isn't possible due to DataWatch and ChildrenWatch
constructs, so we instead need to terminate the daemon to "apply" the
schema update. Thus we use exit code 150 (Application defined in LSB)
and reorder some of the elements of the schema validation to ensure
things happen in the right order.
Joshua Boniface