Multi Channel DMA Intel® FPGA IP for PCI Express Design Example User Guide

ID 683517
Date 10/28/2022
Public

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3.5.2.6.6.2. Transmit Packet Steering (XPS)

Transmit Packet Steering is a mechanism for selecting which transmit queue to use when transmitting a packet on a multi-queue device.

When using XPS, you can map multiple cores to a queue.

Configuration

  • Disable IFC_SELECT_QUEUE_ALGO flag in driver/kmod/mcdma-netdev-driver/Makefile.
  • Map Tx queues to cores:
    echo cpu_mask > /sys/class/net/ifc_mcdma0/queues/tx-i
    cat /sys/class/net/ifc_mcdma0/queues/tx-i
    
    Example
    Map core 0, 1, and 2 to transmit queue 5.
    echo 7 > /sys/class/net/ifc_mcdma0/queues/tx-5