Hi Stephen, Stephen Finucane <step...@that.guru> writes:
> These ports are used to allow ingress/egress from the host and are > therefore _reasonably_ important. However, there is no clear overview of > what these ports actually are or why things are done the way they are. > Start closing this gap by providing a standalone example of using these > ports along with a little more detailed overview of the binding process. > > There is additional cleanup to be done for the DPDK howto, but that will > be done separately. > > Signed-off-by: Stephen Finucane <step...@that.guru> > Cc: Ciara Loftus <ciara.lof...@intel.com> > Cc: Kevin Traynor <ktray...@redhat.com> > --- > Documentation/topics/dpdk/index.rst | 1 + > Documentation/topics/dpdk/phy.rst | 111 > ++++++++++++++++++++++++++++++++++++ > 2 files changed, 112 insertions(+) > create mode 100644 Documentation/topics/dpdk/phy.rst > > diff --git a/Documentation/topics/dpdk/index.rst > b/Documentation/topics/dpdk/index.rst > index da148b323..5f836a6e9 100644 > --- a/Documentation/topics/dpdk/index.rst > +++ b/Documentation/topics/dpdk/index.rst > @@ -28,5 +28,6 @@ The DPDK Datapath > .. toctree:: > :maxdepth: 2 > > + phy > vhost-user > ring > diff --git a/Documentation/topics/dpdk/phy.rst > b/Documentation/topics/dpdk/phy.rst > new file mode 100644 > index 000000000..1c18e4e3d > --- /dev/null > +++ b/Documentation/topics/dpdk/phy.rst > @@ -0,0 +1,111 @@ > +.. > + Copyright 2018, Red Hat, Inc. > + > + Licensed under the Apache License, Version 2.0 (the "License"); you may > + not use this file except in compliance with the License. You may obtain > + a copy of the License at > + > + http://www.apache.org/licenses/LICENSE-2.0 > + > + Unless required by applicable law or agreed to in writing, software > + distributed under the License is distributed on an "AS IS" BASIS, > WITHOUT > + WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See > the > + License for the specific language governing permissions and limitations > + under the License. > + > + Convention for heading levels in Open vSwitch documentation: > + > + ======= Heading 0 (reserved for the title in a document) > + ------- Heading 1 > + ~~~~~~~ Heading 2 > + +++++++ Heading 3 > + ''''''' Heading 4 > + > + Avoid deeper levels because they do not render well. > + > +=================== > +DPDK Physical Ports > +=================== > + > +The DPDK datapath provides a way to attach DPDK-backed physical > interfaces to I think it may make more sense: The netdev datapath allows attaching DPDK-backed physical interfaces... > +allow high-performance ingress/egress from the host. > + > +.. versionchanged:: 2.7.0 > + > + Before Open vSwitch 2.7.0, it was necessary to prefix port names with a > + ``dpdk`` prefix. Starting with 2.7.0, this is no longer necessary. > + > +Quick Example > +------------- > + > +This example demonstrates how to bind two ``dpdk`` ports, bound to physical > +interfaces identified by hardware IDs ``0000:01:00.0`` and ``0000:01:00.1``, > to > +an existing bridge called ``br0``:: > + > + $ ovs-vsctl add-port br0 dpdk-p0 \ > + -- set Interface dpdk-p0 type=dpdk options:dpdk-devargs=0000:01:00.0 > + $ ovs-vsctl add-port br0 dpdk-p1 \ > + -- set Interface dpdk-p1 type=dpdk options:dpdk-devargs=0000:01:00.1 > + > +For the above example to work, the two physical interfaces must be bound to > +the DPDK poll-mode drivers in userspace rather than the traditional kernel > +drivers. See the `binding NIC drivers <dpdk-binding-nics>` section for > details. > + > +.. _dpdk-binding-nics: > + > +Binding NIC Drivers > +------------------- > + > +DPDK operates entirely in userspace and, as a result, requires use of its own > +poll-mode drivers in user space for physical interfaces and a > passthrough-style > +driver for the devices in kernel space. > + > +There are two different tools for binding drivers: :command:`driverctl` which > +is a generic tool for persistently configuring alternative device drivers, > and > +:command:`dpdk-devbind` which is a DPDK-specific tool and whose changes do > not > +persist across reboots. In addition, there are two options available for this > +kernel space driver - VFIO (Virtual Function I/O) and UIO (Userspace I/O) - > +along with a number of drivers for each option. We will demonstrate examples > of > +both tools and will use the ``vfio-pci`` driver, which is the more secure, > +robust driver of those available. More information can be found in the `DPDK > +documentation <dpdk-drivers>`__. Just commentary - really happy to see driverctl getting some love. > + > +To list devices using :command:`driverctl`, run:: > + > + $ driverctl -v list-devices | grep -i net > + 0000:07:00.0 igb (I350 Gigabit Network Connection (Ethernet Server > Adapter I350-T2)) > + 0000:07:00.1 igb (I350 Gigabit Network Connection (Ethernet Server > Adapter I350-T2)) > + > +You can then bind one or more of these devices using the same tool:: > + > + $ driverctl set-override 0000:07:00.0 vfio-pci > + > +Alternatively, to list devices using :command:`dpdk-devbind`, run:: > + > + $ dpdk-devbind --status > + Network devices using DPDK-compatible driver > + ============================================ > + <none> > + > + Network devices using kernel driver > + =================================== > + 0000:07:00.0 'I350 Gigabit Network Connection 1521' if=enp7s0f0 drv=igb > unused=igb_uio > + 0000:07:00.1 'I350 Gigabit Network Connection 1521' if=enp7s0f1 drv=igb > unused=igb_uio > + > + Other Network devices > + ===================== > + ... > + > +Once again, you can then bind one or more of these devices using the same > +tool:: > + > + $ dpdk-devbind --bind=vfio-pci 0000:07:00.0 > + > +.. versionchanged:: 2.6.0 > + > + Open vSwitch 2.6.0 added support for DPDK 16.07, which in turn renamed the > + former ``dpdk_nic_bind`` tool to ``dpdk-devbind``. > + > +For more information, refer to the `DPDK documentation <dpdk-drivers>`__. > + > +.. _dpdk-drivers: http://dpdk.org/doc/guides/linux_gsg/linux_drivers.html _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
