netdevsim devlink support

This document describes the devlink features supported by the netdevsim device driver.

Parameters

Generic parameters implemented

Name	Mode
max_macs	driverinit

The netdevsim driver also implements the following driver-specific parameters.

Driver-specific parameters implemented

Name	Type	Mode	Description
test1	Boolean	driverinit	Test parameter used to show how a driver-specific devlink parameter can be implemented.

The netdevsim driver supports reloading via DEVLINK_CMD_RELOAD

Regions

The netdevsim driver exposes a dummy region as an example of how the devlink-region interfaces work. A snapshot is taken whenever the take_snapshot debugfs file is written to.

Resources

The netdevsim driver exposes resources to control the number of FIB entries, FIB rule entries and nexthops that the driver will allow.

$ devlink resource set netdevsim/netdevsim0 path /IPv4/fib size 96
$ devlink resource set netdevsim/netdevsim0 path /IPv4/fib-rules size 16
$ devlink resource set netdevsim/netdevsim0 path /IPv6/fib size 64
$ devlink resource set netdevsim/netdevsim0 path /IPv6/fib-rules size 16
$ devlink resource set netdevsim/netdevsim0 path /nexthops size 16
$ devlink dev reload netdevsim/netdevsim0

Rate objects

The netdevsim driver supports rate objects management, which includes:

• registerging/unregistering leaf rate objects per VF devlink port;

• creation/deletion node rate objects;

• setting tx_share and tx_max rate values for any rate object type;

• setting parent node for any rate object type.

Rate nodes and their parameters are exposed in netdevsim debugfs in RO mode. For example created rate node with name some_group:

$ ls /sys/kernel/debug/netdevsim/netdevsim0/rate_groups/some_group
rate_parent  tx_max  tx_share

Same parameters are exposed for leaf objects in corresponding ports directories. For ex.:

$ ls /sys/kernel/debug/netdevsim/netdevsim0/ports/1
dev  ethtool  rate_parent  tx_max  tx_share

Driver-specific Traps

List of Driver-specific Traps Registered by netdevsim

Name	Type	Description
fid_miss	exception	When a packet enters the device it is classified to a filtering identifier (FID) based on the ingress port and VLAN. This trap is used to trap packets for which a FID could not be found