232. Fortville: Support of RX Packet Filtering using VMDQ & DCB Features

The Intel Network Interface Card(e.g. XL710), supports a number of packet filtering functions which can be used to distribute incoming packets into a number of reception (RX) queues. VMDQ & DCB is a pair of such filtering functions which operate on VLAN-tagged packets to distribute those packets to RX queues.

The feature itself works by:

  • splitting the incoming packets up into different “pools” - each with its own set of RX queues - based upon the VLAN ID within the VLAN tag of the packet.
  • assigning each packet to a specific queue within the pool, based upon the user priority field within the VLAN tag.

The VMDQ & DCB features are enabled in the vmdq_dcb example application contained in the DPDK, and this application should be used to validate the feature.

232.1. Prerequisites

  • The DPDK is compiled for the appropriate target type in each case, and the VMDQ & DCB example application is compiled and linked with that DPDK instance
  • Two ports are connected to the test system, one to be used for packet reception, the other for transmission
  • The traffic generator being used is configured to send to the application RX port a stream of packets with VLAN tags, where the VLAN IDs increment from 0 to the pools numbers(inclusive) and the VLAN user priority field increments from 0 to 7 (inclusive) for each VLAN ID.
  • Build vmdq_dcb example, make -C examples/vmdq_dcb RTE_SDK=`pwd` T=x86_64-native-linuxapp-gcc

232.2. Test Case 1: Verify VMDQ & DCB with 32 Pools and 4 TCs

  1. Run the application as the following:

    ./examples/vmdq_dcb/build/vmdq_dcb_app -c 0xff -n 4 -- -p 0x3 --nb-pools 32 --nb-tcs 4 --enable-rss

  2. Start traffic transmission using approx 10% of line rate.

  3. After a number of seconds, e.g. 15, stop traffic, and ensure no traffic loss (<0.001%) has occurred.

  4. Send a hangup signal (SIGHUP) to the application to have it print out the statistics of how many packets were received per RX queue:

    kill -s SIGHUP  `pgrep -fl vmdq_dcb_app | awk '{print $1}'`

Expected Result:

  • No packet loss is expected.
  • Every RX queue should have received approximately (+/-15%) the same number of incoming packets
  • verify queue id should be equal “vlan user priority value % 4”.

232.3. Test Case 2: Verify VMDQ & DCB with 16 Pools and 8 TCs

  1. change CONFIG_RTE_LIBRTE_I40E_QUEUE_NUM_PER_VM to 8 in ”./config/common_linuxapp”, rebuild DPDK.

  2. Repeat Test Case 1, with –nb-pools 16 and –nb-tcs 8 of the sample application:

    ./examples/vmdq_dcb/build/vmdq_dcb_app -c 0xff -n 4 -- -p 0x3 --nb-pools 16 --nb-tcs 8 --enable-rss

Expected result: - No packet loss is expected - Every RX queue should have received approximately (+/-15%) the same number of incoming packets - verify queue should be equal “vlan user priority value”

  1. change CONFIG_RTE_LIBRTE_I40E_QUEUE_NUM_PER_VM to 16 in ”./config/common_linuxapp”, rebuild DPDK.

  2. Repeat Test Case 1, with –nb-pools 16 and –nb-tcs 8 of the sample application:

    ./examples/vmdq_dcb/build/vmdq_dcb_app -c 0xff -n 4 -- -p 0x3 --nb-pools 16 --nb-tcs 8 --enable-rss

Expected result: - No packet loss is expected - Every RX queue should have received approximately (+/-15%) the same number of incoming packets - verify queue id should be in [vlan user priority value * 2, vlan user priority value * 2 + 1]

(NOTE: SIGHUP output will obviously change to show 8 columns per row, with only 16 rows)