51 lines
1.7 KiB
ReStructuredText
51 lines
1.7 KiB
ReStructuredText
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.. SPDX-License-Identifier: BSD-3-Clause
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Copyright(c) 2019 Intel Corporation.
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AF_XDP Poll Mode Driver
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==========================
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AF_XDP is an address family that is optimized for high performance
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packet processing. AF_XDP sockets enable the possibility for XDP program to
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redirect packets to a memory buffer in userspace.
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For the full details behind AF_XDP socket, you can refer to
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`AF_XDP documentation in the Kernel
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<https://www.kernel.org/doc/Documentation/networking/af_xdp.rst>`_.
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This Linux-specific PMD driver creates the AF_XDP socket and binds it to a
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specific netdev queue, it allows a DPDK application to send and receive raw
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packets through the socket which would bypass the kernel network stack.
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Current implementation only supports single queue, multi-queues feature will
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be added later.
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Note that MTU of AF_XDP PMD is limited due to XDP lacks support for
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fragmentation.
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Options
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-------
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The following options can be provided to set up an af_xdp port in DPDK.
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* ``iface`` - name of the Kernel interface to attach to (required);
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* ``queue`` - netdev queue id (optional, default 0);
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Prerequisites
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-------------
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This is a Linux-specific PMD, thus the following prerequisites apply:
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* A Linux Kernel (version > v4.18) with XDP sockets configuration enabled;
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* libbpf (within kernel version > v5.1-rc4) with latest af_xdp support installed,
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User can install libbpf via `make install_lib` && `make install_headers` in
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<kernel src tree>/tools/lib/bpf;
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* A Kernel bound interface to attach to;
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Set up an af_xdp interface
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-----------------------------
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The following example will set up an af_xdp interface in DPDK:
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.. code-block:: console
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--vdev net_af_xdp,iface=ens786f1,queue=0
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