On Mon, 2018-04-09 at 15:15 +0000, Stokes, Ian wrote: > > 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 <[email protected]> > > Cc: Ciara Loftus <[email protected]> > > Cc: Kevin Traynor <[email protected]> > > --- > > 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 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. > > I think an example should be added here for when multiple ports share > the same bus slot function. > > Support for this was added in as part of OVS 2.9. > > If not added here then we need to flag clearly that it's supported > but that users need to consult the dpdk-binding-nic section for > specifics.
This is only a quick intro so I don't think it would belong here. However, we could definitely add this as another section. I'm not familiar with this feature so would it be possible to submit this as a follow-up? I'd be happy to review it from a docs perspective. Stephen > Ian > > + > > +.. _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>`__. > > + > > +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 > > -- > > 2.14.3 > > > > _______________________________________________ > > dev mailing list > > [email protected] > > https://mail.openvswitch.org/mailman/listinfo/ovs-dev _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
