13f8de927a
Such deprecation was commenced in DPDK 21.11. Since then, no parties have objected. Remove. The patch breaks ABI. Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru> Reviewed-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru> Acked-by: Ori Kam <orika@nvidia.com>
875 lines
32 KiB
ReStructuredText
875 lines
32 KiB
ReStructuredText
.. SPDX-License-Identifier: BSD-3-Clause
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Copyright(c) 2018 6WIND S.A.
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.. _switch_representation:
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Switch Representation within DPDK Applications
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==============================================
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.. contents:: :local:
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Introduction
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------------
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Network adapters with multiple physical ports and/or SR-IOV capabilities
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usually support the offload of traffic steering rules between their virtual
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functions (VFs), sub functions (SFs), physical functions (PFs) and ports.
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Like for standard Ethernet switches, this involves a combination of
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automatic MAC learning and manual configuration. For most purposes it is
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managed by the host system and fully transparent to users and applications.
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On the other hand, applications typically found on hypervisors that process
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layer 2 (L2) traffic (such as OVS) need to steer traffic themselves
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according on their own criteria.
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Without a standard software interface to manage traffic steering rules
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between VFs, SFs, PFs and the various physical ports of a given device,
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applications cannot take advantage of these offloads; software processing is
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mandatory even for traffic which ends up re-injected into the device it
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originates from.
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This document describes how such steering rules can be configured through
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the DPDK flow API (**rte_flow**), with emphasis on the SR-IOV use case
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(PF/VF steering) using a single physical port for clarity, however the same
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logic applies to any number of ports without necessarily involving SR-IOV.
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Sub Function
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------------
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Besides SR-IOV, Sub function is a portion of the PCI device, a SF netdev
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has its own dedicated queues(txq, rxq). A SF netdev supports E-Switch
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representation offload similar to existing PF and VF representors.
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A SF shares PCI level resources with other SFs and/or with its parent PCI
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function.
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Sub function is created on-demand, coexists with VFs. Number of SFs is
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limited by hardware resources.
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Port Representors
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-----------------
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In many cases, traffic steering rules cannot be determined in advance;
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applications usually have to process a bit of traffic in software before
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thinking about offloading specific flows to hardware.
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Applications therefore need the ability to receive and inject traffic to
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various device endpoints (other VFs, SFs, PFs or physical ports) before
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connecting them together. Device drivers must provide means to hook the
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"other end" of these endpoints and to refer them when configuring flow
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rules.
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This role is left to so-called "port representors" (also known as "VF
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representors" in the specific context of VFs, "SF representors" in the
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specific context of SFs), which are to DPDK what the Ethernet switch
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device driver model (**switchdev**) [1]_ is to Linux, and which can be
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thought as a software "patch panel" front-end for applications.
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- DPDK port representors are implemented as additional virtual Ethernet
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device (**ethdev**) instances, spawned on an as needed basis through
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configuration parameters passed to the driver of the underlying
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device using devargs.
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::
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-a pci:dbdf,representor=vf0
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-a pci:dbdf,representor=vf[0-3]
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-a pci:dbdf,representor=vf[0,5-11]
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-a pci:dbdf,representor=sf1
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-a pci:dbdf,representor=sf[0-1023]
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-a pci:dbdf,representor=sf[0,2-1023]
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- As virtual devices, they may be more limited than their physical
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counterparts, for instance by exposing only a subset of device
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configuration callbacks and/or by not necessarily having Rx/Tx capability.
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- Among other things, they can be used to assign MAC addresses to the
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resource they represent.
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- Applications can tell port representors apart from other physical of virtual
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port by checking the dev_flags field within their device information
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structure for the RTE_ETH_DEV_REPRESENTOR bit-field.
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.. code-block:: c
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struct rte_eth_dev_info {
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...
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uint32_t dev_flags; /**< Device flags */
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...
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};
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- The device or group relationship of ports can be discovered using the
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switch ``domain_id`` field within the devices switch information structure. By
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default the switch ``domain_id`` of a port will be
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``RTE_ETH_DEV_SWITCH_DOMAIN_ID_INVALID`` to indicate that the port doesn't
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support the concept of a switch domain, but ports which do support the concept
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will be allocated a unique switch ``domain_id``, ports within the same switch
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domain will share the same ``domain_id``. The switch ``port_id`` is used to
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specify the port_id in terms of the switch, so in the case of SR-IOV devices
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the switch ``port_id`` would represent the virtual function identifier of the
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port.
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.. code-block:: c
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/**
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* Ethernet device associated switch information
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*/
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struct rte_eth_switch_info {
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const char *name; /**< switch name */
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uint16_t domain_id; /**< switch domain id */
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uint16_t port_id; /**< switch port id */
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};
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.. [1] `Ethernet switch device driver model (switchdev)
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<https://www.kernel.org/doc/Documentation/networking/switchdev.txt>`_
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- For some PMDs, memory usage of representors is huge when number of
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representor grows, mbufs are allocated for each descriptor of Rx queue.
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Polling large number of ports brings more CPU load, cache miss and
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latency. Shared Rx queue can be used to share Rx queue between PF and
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representors among same Rx domain. ``RTE_ETH_DEV_CAPA_RXQ_SHARE`` in
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device info is used to indicate the capability. Setting non-zero share
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group in Rx queue configuration to enable share, share_qid is used to
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identify the shared Rx queue in group. Polling any member port can
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receive packets of all member ports in the group, port ID is saved in
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``mbuf.port``.
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Basic SR-IOV
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------------
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"Basic" in the sense that it is not managed by applications, which
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nonetheless expect traffic to flow between the various endpoints and the
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outside as if everything was linked by an Ethernet hub.
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The following diagram pictures a setup involving a device with one PF, two
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VFs and one shared physical port
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::
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.-------------. .-------------. .-------------.
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| hypervisor | | VM 1 | | VM 2 |
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| application | | application | | application |
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`--+----------' `----------+--' `--+----------'
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.-----+-----. | |
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| port_id 3 | | |
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`-----+-----' | |
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.-+--. .---+--. .--+---.
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| PF | | VF 1 | | VF 2 |
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`-+--' `---+--' `--+---'
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`---------. .-----------------------' |
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| | .-------------------------'
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.--+-----+-----+--.
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| interconnection |
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`--------+--------'
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.----+-----.
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| physical |
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| port 0 |
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`----------'
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- A DPDK application running on the hypervisor owns the PF device, which is
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arbitrarily assigned port index 3.
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- Both VFs are assigned to VMs and used by unknown applications; they may be
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DPDK-based or anything else.
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- Interconnection is not necessarily done through a true Ethernet switch and
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may not even exist as a separate entity. The role of this block is to show
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that something brings PF, VFs and physical ports together and enables
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communication between them, with a number of built-in restrictions.
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Subsequent sections in this document describe means for DPDK applications
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running on the hypervisor to freely assign specific flows between PF, VFs
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and physical ports based on traffic properties, by managing this
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interconnection.
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Controlled SR-IOV
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-----------------
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Initialization
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~~~~~~~~~~~~~~
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When a DPDK application gets assigned a PF device and is deliberately not
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started in `basic SR-IOV`_ mode, any traffic coming from physical ports is
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received by PF according to default rules, while VFs remain isolated.
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::
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.-------------. .-------------. .-------------.
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| hypervisor | | VM 1 | | VM 2 |
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| application | | application | | application |
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`--+----------' `----------+--' `--+----------'
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.-----+-----. | |
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| port_id 3 | | |
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`-----+-----' | |
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.-+--. .---+--. .--+---.
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| PF | | VF 1 | | VF 2 |
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`-+--' `------' `------'
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`-----.
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.--+----------------------.
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| managed interconnection |
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`------------+------------'
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.----+-----.
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| physical |
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| port 0 |
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`----------'
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In this mode, interconnection must be configured by the application to
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enable VF communication, for instance by explicitly directing traffic with a
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given destination MAC address to VF 1 and allowing that with the same source
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MAC address to come out of it.
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For this to work, hypervisor applications need a way to refer to either VF 1
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or VF 2 in addition to the PF. This is addressed by `VF representors`_.
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VF Representors
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~~~~~~~~~~~~~~~
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VF representors are virtual but standard DPDK network devices (albeit with
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limited capabilities) created by PMDs when managing a PF device.
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Since they represent VF instances used by other applications, configuring
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them (e.g. assigning a MAC address or setting up promiscuous mode) affects
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interconnection accordingly. If supported, they may also be used as two-way
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communication ports with VFs (assuming **switchdev** topology)
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::
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.-------------. .-------------. .-------------.
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| hypervisor | | VM 1 | | VM 2 |
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| application | | application | | application |
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`--+---+---+--' `----------+--' `--+----------'
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| | | | |
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| | `-------------------. | |
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| `---------. | | |
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.-----+-----. .-----+-----. .-----+-----. | |
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| port_id 3 | | port_id 4 | | port_id 5 | | |
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`-----+-----' `-----+-----' `-----+-----' | |
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.-+--. .-----+-----. .-----+-----. .---+--. .--+---.
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| PF | | VF 1 rep. | | VF 2 rep. | | VF 1 | | VF 2 |
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`-+--' `-----+-----' `-----+-----' `---+--' `--+---'
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| | .---------' | |
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`-----. | | .-----------------' |
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| | | | .---------------------'
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.--+-------+---+---+---+--.
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| managed interconnection |
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`------------+------------'
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.----+-----.
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| physical |
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| port 0 |
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`----------'
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- VF representors are assigned arbitrary port indices 4 and 5 in the
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hypervisor application and are respectively associated with VF 1 and VF 2.
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- They can't be dissociated; even if VF 1 and VF 2 were not connected,
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representors could still be used for configuration.
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- In this context, port index 3 can be thought as a representor for physical
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port 0.
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As previously described, the "interconnection" block represents a logical
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concept. Interconnection occurs when hardware configuration enables traffic
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flows from one place to another (e.g. physical port 0 to VF 1) according to
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some criteria.
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This is discussed in more detail in `traffic steering`_.
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Traffic Steering
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~~~~~~~~~~~~~~~~
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In the following diagram, each meaningful traffic origin or endpoint as seen
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by the hypervisor application is tagged with a unique letter from A to F.
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::
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.-------------. .-------------. .-------------.
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| hypervisor | | VM 1 | | VM 2 |
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| application | | application | | application |
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`--+---+---+--' `----------+--' `--+----------'
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| | `-------------------. | |
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| `---------. | | |
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.----(A)----. .----(B)----. .----(C)----. | |
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| port_id 3 | | port_id 4 | | port_id 5 | | |
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`-----+-----' `-----+-----' `-----+-----' | |
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.-+--. .-----+-----. .-----+-----. .---+--. .--+---.
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| PF | | VF 1 rep. | | VF 2 rep. | | VF 1 | | VF 2 |
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`-+--' `-----+-----' `-----+-----' `--(D)-' `-(E)--'
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| | | | |
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| | .---------' | |
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`-----. | | .-----------------' |
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| | | | .---------------------'
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.--+-------+---+---+---+--.
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| managed interconnection |
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`------------+------------'
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.---(F)----.
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| physical |
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| port 0 |
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`----------'
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- **A**: PF device.
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- **B**: port representor for VF 1.
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- **C**: port representor for VF 2.
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- **D**: VF 1 proper.
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- **E**: VF 2 proper.
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- **F**: physical port.
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Although uncommon, some devices do not enforce a one to one mapping between
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PF and physical ports. For instance, by default all ports of **mlx4**
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adapters are available to all their PF/VF instances, in which case
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additional ports appear next to **F** in the above diagram.
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Assuming no interconnection is provided by default in this mode, setting up
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a `basic SR-IOV`_ configuration involving physical port 0 could be broken
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down as:
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PF:
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- **A to F**: let everything through.
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- **F to A**: PF MAC as destination.
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VF 1:
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- **A to D**, **E to D** and **F to D**: VF 1 MAC as destination.
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- **D to A**: VF 1 MAC as source and PF MAC as destination.
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- **D to E**: VF 1 MAC as source and VF 2 MAC as destination.
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- **D to F**: VF 1 MAC as source.
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VF 2:
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- **A to E**, **D to E** and **F to E**: VF 2 MAC as destination.
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- **E to A**: VF 2 MAC as source and PF MAC as destination.
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- **E to D**: VF 2 MAC as source and VF 1 MAC as destination.
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- **E to F**: VF 2 MAC as source.
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Devices may additionally support advanced matching criteria such as
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IPv4/IPv6 addresses or TCP/UDP ports.
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The combination of matching criteria with target endpoints fits well with
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**rte_flow** [6]_, which expresses flow rules as combinations of patterns
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and actions.
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Enhancing **rte_flow** with the ability to make flow rules match and target
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these endpoints provides a standard interface to manage their
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interconnection without introducing new concepts and whole new API to
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implement them. This is described in `flow API (rte_flow)`_.
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.. [6] :doc:`Generic flow API (rte_flow) <rte_flow>`
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Flow API (rte_flow)
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-------------------
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Extensions
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~~~~~~~~~~
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Compared to creating a brand new dedicated interface, **rte_flow** was
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deemed flexible enough to manage representor traffic only with minor
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extensions:
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- Using physical ports, PF, SF, VF or port representors as targets.
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- Affecting traffic that is not necessarily addressed to the DPDK port ID a
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flow rule is associated with (e.g. forcing VF traffic redirection to PF).
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For advanced uses:
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- Rule-based packet counters.
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- The ability to combine several identical actions for traffic duplication
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(e.g. VF representor in addition to a physical port).
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- Dedicated actions for traffic encapsulation / decapsulation before
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reaching an endpoint.
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Traffic Direction
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~~~~~~~~~~~~~~~~~
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From an application standpoint, "ingress" and "egress" flow rule attributes
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apply to the DPDK port ID they are associated with. They select a traffic
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direction for matching patterns, but have no impact on actions.
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When matching traffic coming from or going to a different place than the
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immediate port ID a flow rule is associated with, these attributes keep
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their meaning while applying to the chosen origin, as highlighted by the
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following diagram
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::
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.-------------. .-------------. .-------------.
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| hypervisor | | VM 1 | | VM 2 |
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| application | | application | | application |
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`--+---+---+--' `----------+--' `--+----------'
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| | `-------------------. | |
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| `---------. | | |
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| ^ | ^ | ^ | |
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| | ingress | | ingress | | ingress | |
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| | egress | | egress | | egress | |
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| v | v | v | |
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.----(A)----. .----(B)----. .----(C)----. | |
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| port_id 3 | | port_id 4 | | port_id 5 | | |
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`-----+-----' `-----+-----' `-----+-----' | |
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| | | | |
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.-+--. .-----+-----. .-----+-----. .---+--. .--+---.
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| PF | | VF 1 rep. | | VF 2 rep. | | VF 1 | | VF 2 |
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`-+--' `-----+-----' `-----+-----' `--(D)-' `-(E)--'
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| | | ^ | | ^
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| | | egress | | | | egress
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| | | ingress | | | | ingress
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| | .---------' v | | v
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`-----. | | .-----------------' |
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| | | | .---------------------'
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.--+-------+---+---+---+--.
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| managed interconnection |
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`------------+------------'
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^ |
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ingress | |
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egress | |
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v |
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.---(F)----.
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| physical |
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| port 0 |
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`----------'
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Ingress and egress are defined as relative to the application creating the
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flow rule.
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For instance, matching traffic sent by VM 2 would be done through an ingress
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flow rule on VF 2 (**E**). Likewise for incoming traffic on physical port
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(**F**). This also applies to **C** and **A** respectively.
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Transferring Traffic
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~~~~~~~~~~~~~~~~~~~~
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Without Port Representors
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^^^^^^^^^^^^^^^^^^^^^^^^^
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`Traffic direction`_ describes how an application could match traffic coming
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from or going to a specific place reachable from a DPDK port ID. This makes
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sense when the traffic in question is normally seen (i.e. sent or received)
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by the application creating the flow rule.
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However, if there is an entity (VF **D**, for instance) not associated with
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a DPDK port (representor), the application (**A**) won't be able to match
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traffic generated by such entity. The traffic goes directly to its
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default destination (to physical port **F**, for instance).
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::
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.-------------. .-------------.
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| hypervisor | | VM 1 |
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| application | | application |
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`------+------' `--+----------'
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| | | traffic
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.----(A)----. | v
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| port_id 3 | |
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`-----+-----' |
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| |
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.-+--. .---+--.
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| PF | | VF 1 |
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`-+--' `--(D)-'
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| | | traffic
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| | v
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.--+-----------+--.
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| interconnection |
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`--------+--------'
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| | traffic
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| v
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.---(F)----.
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| physical |
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| port 0 |
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`----------'
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With Port Representors
|
|
^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
When port representors exist, implicit flow rules with the "transfer"
|
|
attribute (described in `without port representors`_) are be assumed to
|
|
exist between them and their represented resources. These may be immutable.
|
|
|
|
In this case, traffic is received by default through the representor and
|
|
neither the "transfer" attribute nor traffic origin in flow rule patterns
|
|
are necessary. They simply have to be created on the representor port
|
|
directly and may target a different representor as described
|
|
in `PORT_REPRESENTOR Action`_.
|
|
|
|
Implicit traffic flow with port representor
|
|
|
|
::
|
|
|
|
.-------------. .-------------.
|
|
| hypervisor | | VM 1 |
|
|
| application | | application |
|
|
`--+-------+--' `----------+--'
|
|
| | ^ | | traffic
|
|
| | | traffic | v
|
|
| `-----. |
|
|
| | |
|
|
.----(A)----. .----(B)----. |
|
|
| port_id 3 | | port_id 4 | |
|
|
`-----+-----' `-----+-----' |
|
|
| | |
|
|
.-+--. .-----+-----. .---+--.
|
|
| PF | | VF 1 rep. | | VF 1 |
|
|
`-+--' `-----+-----' `--(D)-'
|
|
| | |
|
|
.--|-------------|-----------|--.
|
|
| | | | |
|
|
| | `-----------' |
|
|
| | <-- traffic |
|
|
`--|----------------------------'
|
|
|
|
|
.---(F)----.
|
|
| physical |
|
|
| port 0 |
|
|
`----------'
|
|
|
|
Pattern Items And Actions
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
PORT_REPRESENTOR Pattern Item
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Matches traffic entering the embedded switch from the given ethdev.
|
|
|
|
- Matches **A**, **B** or **C** in `traffic steering`_.
|
|
|
|
PORT_REPRESENTOR Action
|
|
^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
At embedded switch level, sends matching traffic to the given ethdev.
|
|
|
|
- Targets **A**, **B** or **C** in `traffic steering`_.
|
|
|
|
REPRESENTED_PORT Pattern Item
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Matches traffic entering the embedded switch from
|
|
the entity represented by the given ethdev.
|
|
|
|
- Matches **D**, **E** or **F** in `traffic steering`_.
|
|
|
|
REPRESENTED_PORT Action
|
|
^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
At embedded switch level, send matching traffic to
|
|
the entity represented by the given ethdev.
|
|
|
|
- Targets **D**, **E** or **F** in `traffic steering`_.
|
|
|
|
PORT Pattern Item
|
|
^^^^^^^^^^^^^^^^^
|
|
|
|
Matches traffic originating from (ingress) or going to (egress) a physical
|
|
port of the underlying device.
|
|
|
|
Using this pattern item without specifying a port index matches the physical
|
|
port associated with the current DPDK port ID by default. As described in
|
|
`traffic steering`_, specifying it should be rarely needed.
|
|
|
|
- Matches **F** in `traffic steering`_.
|
|
|
|
PORT Action
|
|
^^^^^^^^^^^
|
|
|
|
Directs matching traffic to a given physical port index.
|
|
|
|
- Targets **F** in `traffic steering`_.
|
|
|
|
PORT_ID Pattern Item
|
|
^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Matches traffic originating from (ingress) or going to (egress) a given DPDK
|
|
port ID.
|
|
|
|
Normally only supported if the port ID in question is known by the
|
|
underlying PMD and related to the device the flow rule is created against.
|
|
|
|
This must not be confused with the `PORT pattern item`_ which refers to the
|
|
physical port of a device. ``PORT_ID`` refers to a ``struct rte_eth_dev``
|
|
object on the application side (also known as "port representor" depending
|
|
on the kind of underlying device).
|
|
|
|
- Matches **A**, **B** or **C** in `traffic steering`_.
|
|
|
|
PORT_ID Action
|
|
^^^^^^^^^^^^^^
|
|
|
|
Directs matching traffic to a given DPDK port ID.
|
|
|
|
Same restrictions as `PORT_ID pattern item`_.
|
|
|
|
- Targets **A**, **B** or **C** in `traffic steering`_.
|
|
|
|
PF Action
|
|
^^^^^^^^^
|
|
|
|
Directs matching traffic to the physical function of the current device.
|
|
|
|
- Targets **A** in `traffic steering`_.
|
|
|
|
VF Pattern Item
|
|
^^^^^^^^^^^^^^^
|
|
|
|
Matches traffic originating from (ingress) or going to (egress) a given
|
|
virtual function of the current device.
|
|
|
|
If supported, should work even if the virtual function is not managed by
|
|
the application and thus not associated with a DPDK port ID. Its behavior is
|
|
otherwise similar to `PORT_ID pattern item`_ using VF port ID.
|
|
|
|
Note this pattern item does not match VF representors traffic which, as
|
|
separate entities, should be addressed through their own port IDs.
|
|
|
|
- Matches **D** or **E** in `traffic steering`_.
|
|
|
|
VF Action
|
|
^^^^^^^^^
|
|
|
|
Directs matching traffic to a given virtual function of the current device.
|
|
|
|
Same restrictions as `VF pattern item`_.
|
|
|
|
- Targets **D** or **E** in `traffic steering`_.
|
|
|
|
\*_ENCAP actions
|
|
^^^^^^^^^^^^^^^^
|
|
|
|
These actions are named according to the protocol they encapsulate traffic
|
|
with (e.g. ``VXLAN_ENCAP``) and using specific parameters (e.g. VNI for
|
|
VXLAN).
|
|
|
|
While they modify traffic and can be used multiple times (order matters),
|
|
unlike `PORT_REPRESENTOR Action`_ and friends, they don't impact on steering.
|
|
|
|
As described in `actions order and repetition`_ this means they are useless
|
|
if used alone in an action list, the resulting traffic gets dropped unless
|
|
combined with either ``PASSTHRU`` or other endpoint-targeting actions.
|
|
|
|
\*_DECAP actions
|
|
^^^^^^^^^^^^^^^^
|
|
|
|
They perform the reverse of `\*_ENCAP actions`_ by popping protocol headers
|
|
from traffic instead of pushing them. They can be used multiple times as
|
|
well.
|
|
|
|
Note that using these actions on non-matching traffic results in undefined
|
|
behavior. It is recommended to match the protocol headers to decapsulate on
|
|
the pattern side of a flow rule in order to use these actions or otherwise
|
|
make sure only matching traffic goes through.
|
|
|
|
Actions Order and Repetition
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
Flow rules are currently restricted to at most a single action of each
|
|
supported type, performed in an unpredictable order (or all at once). To
|
|
repeat actions in a predictable fashion, applications have to make rules
|
|
pass-through and use priority levels.
|
|
|
|
It's now clear that PMD support for chaining multiple non-terminating flow
|
|
rules of varying priority levels is prohibitively difficult to implement
|
|
compared to simply allowing multiple identical actions performed in a
|
|
defined order by a single flow rule.
|
|
|
|
- This change is required to support protocol encapsulation offloads and the
|
|
ability to perform them multiple times (e.g. VLAN then VXLAN).
|
|
|
|
- It makes the ``DUP`` action redundant since multiple ``QUEUE`` actions can
|
|
be combined for duplication.
|
|
|
|
- The (non-)terminating property of actions must be discarded. Instead, flow
|
|
rules themselves must be considered terminating by default (i.e. dropping
|
|
traffic if there is no specific target) unless a ``PASSTHRU`` action is
|
|
also specified.
|
|
|
|
Switching Examples
|
|
------------------
|
|
|
|
This section provides practical examples based on the established testpmd
|
|
flow command syntax [2]_, in the context described in `traffic steering`_
|
|
|
|
::
|
|
|
|
.-------------. .-------------. .-------------.
|
|
| hypervisor | | VM 1 | | VM 2 |
|
|
| application | | application | | application |
|
|
`--+---+---+--' `----------+--' `--+----------'
|
|
| | | | |
|
|
| | `-------------------. | |
|
|
| `---------. | | |
|
|
| | | | |
|
|
.----(A)----. .----(B)----. .----(C)----. | |
|
|
| port_id 3 | | port_id 4 | | port_id 5 | | |
|
|
`-----+-----' `-----+-----' `-----+-----' | |
|
|
| | | | |
|
|
.-+--. .-----+-----. .-----+-----. .---+--. .--+---.
|
|
| PF | | VF 1 rep. | | VF 2 rep. | | VF 1 | | VF 2 |
|
|
`-+--' `-----+-----' `-----+-----' `--(D)-' `-(E)--'
|
|
| | | | |
|
|
| | .---------' | |
|
|
`-----. | | .-----------------' |
|
|
| | | | .---------------------'
|
|
| | | | |
|
|
.--|-------|---|---|---|--.
|
|
| | | `---|---' |
|
|
| | `-------' |
|
|
| `---------. |
|
|
`------------|------------'
|
|
|
|
|
.---(F)----.
|
|
| physical |
|
|
| port 0 |
|
|
`----------'
|
|
|
|
By default, PF (**A**) can communicate with the physical port it is
|
|
associated with (**F**), while VF 1 (**D**) and VF 2 (**E**) are isolated
|
|
and restricted to communicate with the hypervisor application through their
|
|
respective representors (**B** and **C**) if supported.
|
|
|
|
Examples in subsequent sections apply to hypervisor applications only and
|
|
are based on port representors **A**, **B** and **C**.
|
|
|
|
.. [2] :ref:`Flow syntax <testpmd_rte_flow>`
|
|
|
|
Associating VF 1 with Physical Port 0
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
Assign all port traffic (**F**) to VF 1 (**D**) indiscriminately through
|
|
their representors
|
|
|
|
::
|
|
|
|
flow create 3 transfer
|
|
pattern represented_port ethdev_port_id is 3 / end
|
|
actions represented_port ethdev_port_id 4 / end
|
|
|
|
::
|
|
|
|
flow create 3 transfer
|
|
pattern represented_port ethdev_port_id is 4 / end
|
|
actions represented_port ethdev_port_id 3 / end
|
|
|
|
|
|
Sharing Broadcasts
|
|
~~~~~~~~~~~~~~~~~~
|
|
|
|
From outside to PF and VFs
|
|
|
|
::
|
|
|
|
flow create 3 transfer
|
|
pattern
|
|
represented_port ethdev_port_id is 3 /
|
|
eth dst is ff:ff:ff:ff:ff:ff /
|
|
end
|
|
actions
|
|
port_representor ethdev_port_id 3 /
|
|
represented_port ethdev_port_id 4 /
|
|
represented_port ethdev_port_id 5 /
|
|
end
|
|
|
|
Note ``port_representor ethdev_port_id 3`` is necessary otherwise only VFs would receive matching
|
|
traffic.
|
|
|
|
From PF to outside and VFs
|
|
|
|
::
|
|
|
|
flow create 3 transfer
|
|
pattern
|
|
port_representor ethdev_port_id is 3 /
|
|
eth dst is ff:ff:ff:ff:ff:ff /
|
|
end
|
|
actions
|
|
represented_port ethdev_port_id 3 /
|
|
represented_port ethdev_port_id 4 /
|
|
represented_port ethdev_port_id 5 /
|
|
end
|
|
|
|
From VFs to outside and PF
|
|
|
|
::
|
|
|
|
flow create 3 transfer
|
|
pattern
|
|
represented_port ethdev_port_id is 4 /
|
|
eth dst is ff:ff:ff:ff:ff:ff /
|
|
end
|
|
actions
|
|
represented_port ethdev_port_id 3 /
|
|
port_representor ethdev_port_id 3 /
|
|
end
|
|
|
|
flow create 3 transfer
|
|
pattern
|
|
represented_port ethdev_port_id is 5 /
|
|
eth dst is ff:ff:ff:ff:ff:ff /
|
|
end
|
|
actions
|
|
represented_port ethdev_port_id 3 /
|
|
port_representor ethdev_port_id 3 /
|
|
end
|
|
|
|
Similar ``33:33:*`` rules based on known MAC addresses should be added for
|
|
IPv6 traffic.
|
|
|
|
Encapsulating VF 2 Traffic in VXLAN
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
Assuming pass-through flow rules are supported
|
|
|
|
::
|
|
|
|
flow create 5 ingress
|
|
pattern eth / end
|
|
actions vxlan_encap vni 42 / passthru / end
|
|
|
|
::
|
|
|
|
flow create 5 egress
|
|
pattern vxlan vni is 42 / end
|
|
actions vxlan_decap / passthru / end
|
|
|
|
Here ``passthru`` is needed since as described in `actions order and
|
|
repetition`_, flow rules are otherwise terminating; if supported, a rule
|
|
without a target endpoint will drop traffic.
|
|
|
|
Without pass-through support, ingress encapsulation on the destination
|
|
endpoint might not be supported and action list must provide one
|
|
|
|
::
|
|
|
|
flow create 3 transfer
|
|
pattern represented_port ethdev_port_id is 5 / end
|
|
actions vxlan_encap vni 42 / represented_port ethdev_port_id 3 / end
|
|
|
|
flow create 3 transfer
|
|
pattern
|
|
represented_port ethdev_port_id is 3 /
|
|
vxlan vni is 42 /
|
|
end
|
|
actions vxlan_decap / represented_port ethdev_port_id 5 / end
|