3. Ethtool Sample Application

The Ethtool sample application shows an implementation of an ethtool-like API and provides a console environment that allows its use to query and change Ethernet card parameters. The sample is based upon a simple L2 frame reflector.

3.1. Compiling the Application

To compile the application:

  1. Go to the sample application directory:

    export RTE_SDK=/path/to/rte_sdk
cd ${RTE_SDK}/examples/ethtool

  2. Set the target (a default target is used if not specified). For example:

    export RTE_TARGET=x86_64-native-linuxapp-gcc

    See the DPDK Getting Started Guide for possible RTE_TARGET values.

  3. Build the application:

    make

3.2. Running the Application

The application requires an available core for each port, plus one. The only available options are the standard ones for the EAL:

./ethtool-app/ethtool-app/${RTE_TARGET}/ethtool [EAL options]

Refer to the DPDK Getting Started Guide for general information on running applications and the Environment Abstraction Layer (EAL) options.

3.3. Using the application

The application is console-driven using the cmdline DPDK interface:

EthApp>

From this interface the available commands and descriptions of what they do as as follows:

  • drvinfo: Print driver info
  • eeprom: Dump EEPROM to file
  • link: Print port link states
  • macaddr: Gets/sets MAC address
  • mtu: Set NIC MTU
  • open: Open port
  • pause: Get/set port pause state
  • portstats: Print port statistics
  • regs: Dump port register(s) to file
  • ringparam: Get/set ring parameters
  • rxmode: Toggle port Rx mode
  • stop: Stop port
  • validate: Check that given MAC address is valid unicast address
  • vlan: Add/remove VLAN id
  • quit: Exit program

3.4. Explanation

The sample program has two parts: A background packet reflector that runs on a slave core, and a foreground Ethtool Shell that runs on the master core. These are described below.

3.4.1. Packet Reflector

The background packet reflector is intended to demonstrate basic packet processing on NIC ports controlled by the Ethtool shim. Each incoming MAC frame is rewritten so that it is returned to the sender, using the port in question’s own MAC address as the source address, and is then sent out on the same port.

3.4.2. Ethtool Shell

The foreground part of the Ethtool sample is a console-based interface that accepts commands as described in using the application. Individual call-back functions handle the detail associated with each command, which make use of the functions defined in the Ethtool interface to the DPDK functions.

3.5. Ethtool interface

The Ethtool interface is built as a separate library, and implements the following functions:

  • rte_ethtool_get_drvinfo()
  • rte_ethtool_get_regs_len()
  • rte_ethtool_get_regs()
  • rte_ethtool_get_link()
  • rte_ethtool_get_eeprom_len()
  • rte_ethtool_get_eeprom()
  • rte_ethtool_set_eeprom()
  • rte_ethtool_get_pauseparam()
  • rte_ethtool_set_pauseparam()
  • rte_ethtool_net_open()
  • rte_ethtool_net_stop()
  • rte_ethtool_net_get_mac_addr()
  • rte_ethtool_net_set_mac_addr()
  • rte_ethtool_net_validate_addr()
  • rte_ethtool_net_change_mtu()
  • rte_ethtool_net_get_stats64()
  • rte_ethtool_net_vlan_rx_add_vid()
  • rte_ethtool_net_vlan_rx_kill_vid()
  • rte_ethtool_net_set_rx_mode()
  • rte_ethtool_get_ringparam()
  • rte_ethtool_set_ringparam()