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diff --git a/src/spdk/dpdk/doc/guides/nics/kni.rst b/src/spdk/dpdk/doc/guides/nics/kni.rst new file mode 100644 index 000000000..90d3040cf --- /dev/null +++ b/src/spdk/dpdk/doc/guides/nics/kni.rst @@ -0,0 +1,170 @@ +.. SPDX-License-Identifier: BSD-3-Clause + Copyright(c) 2017 Intel Corporation. + +KNI Poll Mode Driver +====================== + +KNI PMD is wrapper to the :ref:`librte_kni <kni>` library. + +This PMD enables using KNI without having a KNI specific application, +any forwarding application can use PMD interface for KNI. + +Sending packets to any DPDK controlled interface or sending to the +Linux networking stack will be transparent to the DPDK application. + +To create a KNI device ``net_kni#`` device name should be used, and this +will create ``kni#`` Linux virtual network interface. + +There is no physical device backend for the virtual KNI device. + +Packets sent to the KNI Linux interface will be received by the DPDK +application, and DPDK application may forward packets to a physical NIC +or to a virtual device (like another KNI interface or PCAP interface). + +To forward any traffic from physical NIC to the Linux networking stack, +an application should control a physical port and create one virtual KNI port, +and forward between two. + +Using this PMD requires KNI kernel module be inserted. + + +Usage +----- + +EAL ``--vdev`` argument can be used to create KNI device instance, like:: + + testpmd --vdev=net_kni0 --vdev=net_kn1 -- -i + +Above command will create ``kni0`` and ``kni1`` Linux network interfaces, +those interfaces can be controlled by standard Linux tools. + +When testpmd forwarding starts, any packets sent to ``kni0`` interface +forwarded to the ``kni1`` interface and vice versa. + +There is no hard limit on number of interfaces that can be created. + + +Default interface configuration +------------------------------- + +``librte_kni`` can create Linux network interfaces with different features, +feature set controlled by a configuration struct, and KNI PMD uses a fixed +configuration: + + .. code-block:: console + + Interface name: kni# + force bind kernel thread to a core : NO + mbuf size: (rte_pktmbuf_data_room_size(pktmbuf_pool) - RTE_PKTMBUF_HEADROOM) + mtu: (conf.mbuf_size - RTE_ETHER_HDR_LEN) + +KNI control path is not supported with the PMD, since there is no physical +backend device by default. + + +PMD arguments +------------- + +``no_request_thread``, by default PMD creates a pthread for each KNI interface +to handle Linux network interface control commands, like ``ifconfig kni0 up`` + +With ``no_request_thread`` option, pthread is not created and control commands +not handled by PMD. + +By default request thread is enabled. And this argument should not be used +most of the time, unless this PMD used with customized DPDK application to handle +requests itself. + +Argument usage:: + + testpmd --vdev "net_kni0,no_request_thread=1" -- -i + + +PMD log messages +---------------- + +If KNI kernel module (rte_kni.ko) not inserted, following error log printed:: + + "KNI: KNI subsystem has not been initialized. Invoke rte_kni_init() first" + + +PMD testing +----------- + +It is possible to test PMD quickly using KNI kernel module loopback feature: + +* Insert KNI kernel module with loopback support: + + .. code-block:: console + + insmod build/kmod/rte_kni.ko lo_mode=lo_mode_fifo_skb + +* Start testpmd with no physical device but two KNI virtual devices: + + .. code-block:: console + + ./testpmd --vdev net_kni0 --vdev net_kni1 -- -i + + .. code-block:: console + + ... + Configuring Port 0 (socket 0) + KNI: pci: 00:00:00 c580:b8 + Port 0: 1A:4A:5B:7C:A2:8C + Configuring Port 1 (socket 0) + KNI: pci: 00:00:00 600:b9 + Port 1: AE:95:21:07:93:DD + Checking link statuses... + Port 0 Link Up - speed 10000 Mbps - full-duplex + Port 1 Link Up - speed 10000 Mbps - full-duplex + Done + testpmd> + +* Observe Linux interfaces + + .. code-block:: console + + $ ifconfig kni0 && ifconfig kni1 + kni0: flags=4098<BROADCAST,MULTICAST> mtu 1500 + ether ae:8e:79:8e:9b:c8 txqueuelen 1000 (Ethernet) + RX packets 0 bytes 0 (0.0 B) + RX errors 0 dropped 0 overruns 0 frame 0 + TX packets 0 bytes 0 (0.0 B) + TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 + + kni1: flags=4098<BROADCAST,MULTICAST> mtu 1500 + ether 9e:76:43:53:3e:9b txqueuelen 1000 (Ethernet) + RX packets 0 bytes 0 (0.0 B) + RX errors 0 dropped 0 overruns 0 frame 0 + TX packets 0 bytes 0 (0.0 B) + TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 + + +* Start forwarding with tx_first: + + .. code-block:: console + + testpmd> start tx_first + +* Quit and check forwarding stats: + + .. code-block:: console + + testpmd> quit + Telling cores to stop... + Waiting for lcores to finish... + + ---------------------- Forward statistics for port 0 ---------------------- + RX-packets: 35637905 RX-dropped: 0 RX-total: 35637905 + TX-packets: 35637947 TX-dropped: 0 TX-total: 35637947 + ---------------------------------------------------------------------------- + + ---------------------- Forward statistics for port 1 ---------------------- + RX-packets: 35637915 RX-dropped: 0 RX-total: 35637915 + TX-packets: 35637937 TX-dropped: 0 TX-total: 35637937 + ---------------------------------------------------------------------------- + + +++++++++++++++ Accumulated forward statistics for all ports+++++++++++++++ + RX-packets: 71275820 RX-dropped: 0 RX-total: 71275820 + TX-packets: 71275884 TX-dropped: 0 TX-total: 71275884 + ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |