6. NFP vDPA driver
The NFP vDPA (vhost data path acceleration) driver (librte_nfp_vdpa) provides support for the Netronome and Corigine’s NFP-6xxx, NFP-4xxx and NFP-38xx product lines.
6.1. NFP vDPA implementation
NFP VF device can be configured in the net device or vDPA mode. Adding “class=vdpa” parameter helps to specify that this device is to be used in vDPA mode. If this parameter is not specified, device will be probed by net/nfp driver and will used as a VF net device.
This PMD uses (common/nfp) code to access the device firmware.
6.1.1. Software Live Migration
Now the NFP vDPA driver only supports software assisted live migration mode. In this mode, the driver will setup a software relay thread when live migration happens, this thread will help device to log dirty pages. Although this mode does not require hardware to implement a dirty page logging function block, it will consume percentage of CPU resource depending on the network throughput.
6.1.2. Per-Device Parameters
The following per-device parameters can be passed via EAL PCI device allow-list option like “-a 02:00.0,arg1=value1,…”.
class[net|vdpa] (default net)Choose the mode of operation of nfp device. net device will work as network device and will be probed by net/nfp driver. vdpa device will work as vdpa device and will be probed by vdpa/nfp driver. If this parameter is not specified then nfp device will operate as network device.
6.1.3. Dynamic Logging Parameters
One may leverage EAL option “–log-level” to change default levels for the log types supported by the driver. The option is used with an argument typically consisting of two parts separated by a colon.
Level value is the last part which takes a symbolic name (or integer). Log type is the former part which may shell match syntax. Depending on the choice of the expression, the given log level may be used either for some specific log type or for a subset of types.
NFP vDPA PMD provides the following log types available for control:
pmd.vdpa.nfp.vdpa(default level is notice)Affects driver-wide messages unrelated to any particular devices.
pmd.vdpa.nfp.core(default level is notice)Affects the core logic of this PMD.