> The "hotplugging", "flow control", and "Rx checksum offload" sections only > apply to 'dpdk' ports and are too detailed to include in a high-level > howto. Move them, reworking some aspects of this in the process. > > Signed-off-by: Stephen Finucane <step...@that.guru> > --- > v2: > - Split out vdev into its own document (and patch) > - Add cross-references from DPDK howto guide to detailed topic guides > - Add flow control > --- > Documentation/howto/dpdk.rst | 103 ++++++------------------------- > ----- > Documentation/topics/dpdk/index.rst | 11 ++-- > Documentation/topics/dpdk/phy.rst | 86 ++++++++++++++++++++++++++++++ > 3 files changed, 110 insertions(+), 90 deletions(-)
LGTM. Ian > > diff --git a/Documentation/howto/dpdk.rst b/Documentation/howto/dpdk.rst > index 388728363..531612880 100644 > --- a/Documentation/howto/dpdk.rst > +++ b/Documentation/howto/dpdk.rst > @@ -57,8 +57,12 @@ usage is suggested:: > $ ovs-vsctl add-port br0 dpdk-p1 -- set Interface dpdk-p1 type=dpdk \ > options:dpdk-devargs="class=eth,mac=00:11:22:33:44:55:02" > > -Note: such syntax won't support hotplug. The hotplug is supposed to work > with -future DPDK release, v18.05. > +.. important:: > + > + Hotplugging physical interfaces is not supported using the above > syntax. > + This is expected to change with the release of DPDK v18.05. For > information > + on hotplugging physical interfaces, you should instead refer to > + :ref:`port-hotplug`. > > After the DPDK ports get added to switch, a polling thread continuously > polls DPDK devices and consumes 100% of the core, as can be checked from > ``top`` and @@ -123,34 +127,6 @@ To clear the ingress policer > configuration from the port:: > > Refer to vswitch.xml for more details on ingress-policer. > > -Flow Control > ------------- > - > -Flow control can be enabled only on DPDK physical ports. To enable flow > control -support at tx side while adding a port, run:: > - > - $ ovs-vsctl add-port br0 dpdk-p0 -- set Interface dpdk-p0 type=dpdk \ > - options:dpdk-devargs=0000:01:00.0 options:tx-flow-ctrl=true > - > -Similarly, to enable rx flow control, run:: > - > - $ ovs-vsctl add-port br0 dpdk-p0 -- set Interface dpdk-p0 type=dpdk \ > - options:dpdk-devargs=0000:01:00.0 options:rx-flow-ctrl=true > - > -To enable flow control auto-negotiation, run:: > - > - $ ovs-vsctl add-port br0 dpdk-p0 -- set Interface dpdk-p0 type=dpdk \ > - options:dpdk-devargs=0000:01:00.0 options:flow-ctrl-autoneg=true > - > -To turn ON the tx flow control at run time for an existing port, run:: > - > - $ ovs-vsctl set Interface dpdk-p0 options:tx-flow-ctrl=true > - > -The flow control parameters can be turned off by setting ``false`` to the > -respective parameter. To disable the flow control at tx side, run:: > - > - $ ovs-vsctl set Interface dpdk-p0 options:tx-flow-ctrl=false > - > pdump > ----- > > @@ -236,16 +212,6 @@ largest frame size supported by Fortville NIC using > the DPDK i40e driver, but larger frames and other DPDK NIC drivers may be > supported. These cases are common for use cases involving East-West > traffic only. > > -Rx Checksum Offload > -------------------- > - > -By default, DPDK physical ports are enabled with Rx checksum offload. > - > -Rx checksum offload can offer performance improvement only for tunneling > -traffic in OVS-DPDK because the checksum validation of tunnel packets is > -offloaded to the NIC. Also enabling Rx checksum may slightly reduce the - > performance of non-tunnel traffic, specifically for smaller size packet. > - > .. _extended-statistics: > > Extended & Custom Statistics > @@ -278,52 +244,6 @@ Note about "Extended Statistics": vHost ports > supports only partial statistics. RX packet size based counter are only > supported and doesn't include TX packet size counters. > > -.. _port-hotplug: > - > -Port Hotplug > ------------- > - > -OVS supports port hotplugging, allowing the use of ports that were not > bound -to DPDK when vswitchd was started. > -In order to attach a port, it has to be bound to DPDK using the - > ``dpdk_nic_bind.py`` script:: > - > - $ $DPDK_DIR/tools/dpdk_nic_bind.py --bind=igb_uio 0000:01:00.0 > - > -Then it can be attached to OVS:: > - > - $ ovs-vsctl add-port br0 dpdkx -- set Interface dpdkx type=dpdk \ > - options:dpdk-devargs=0000:01:00.0 > - > -Detaching will be performed while processing del-port command:: > - > - $ ovs-vsctl del-port dpdkx > - > -Sometimes, the del-port command may not detach the device. > -Detaching can be confirmed by the appearance of an INFO log. > -For example:: > - > - INFO|Device '0000:04:00.1' has been detached > - > -If the log is not seen, then the port can be detached using:: > - > -$ ovs-appctl netdev-dpdk/detach 0000:01:00.0 > - > -Detaching can be confirmed by console output:: > - > - Device '0000:04:00.1' has been detached > - > -.. warning:: > - Detaching should not be done if a device is known to be non- > detachable, as > - this may cause the device to behave improperly when added back with > - add-port. The Chelsio Terminator adapters which use the cxgbe driver > seem > - to be an example of this behavior; check the driver documentation if > this > - is suspected. > - > -This feature does not work with some NICs. > -For more information please refer to the `DPDK Port Hotplug Framework - > <http://dpdk.org/doc/guides/prog_guide/port_hotplug_framework.html#hotplug > >`__. > - > .. _vdev-support: > > Vdev Support > @@ -653,3 +573,14 @@ devices to bridge ``br0``. Once complete, follow the > below steps: > Check traffic on multiple queues:: > > $ cat /proc/interrupts | grep virtio > + > +Further Reading > +--------------- > + > +More detailed information can be found in the :doc:`DPDK topics section > +</topics/dpdk/index>` of the documentation. These guides are listed > below. > + > +.. NOTE(stephenfin): Remember to keep this in sync with > +topics/dpdk/index > + > +.. include:: ../topics/dpdk/index.rst > + :start-line: 30 > diff --git a/Documentation/topics/dpdk/index.rst > b/Documentation/topics/dpdk/index.rst > index dfde88377..4b4dc119a 100644 > --- a/Documentation/topics/dpdk/index.rst > +++ b/Documentation/topics/dpdk/index.rst > @@ -25,10 +25,13 @@ > The DPDK Datapath > ================= > > +.. NOTE(stephenfin): Part of this doc is included in 'howto/dpdk'. > +Update that .. if you modify this document > + > .. toctree:: > :maxdepth: 2 > > - phy > - vhost-user > - ring > - pmd > + /topics/dpdk/phy > + /topics/dpdk/vhost-user > + /topics/dpdk/ring > + /topics/dpdk/pmd > diff --git a/Documentation/topics/dpdk/phy.rst > b/Documentation/topics/dpdk/phy.rst > index ad191dad0..929f394ea 100644 > --- a/Documentation/topics/dpdk/phy.rst > +++ b/Documentation/topics/dpdk/phy.rst > @@ -125,3 +125,89 @@ utilize is a requirement in order to deliver the > high-performance possible with DPDK acceleration. It is possible to > configure multiple Rx queues for ``dpdk`` ports, thus ensuring this is > not a bottleneck for performance. For information on configuring PMD > threads, refer to :doc:`pmd`. > + > +Flow Control > +------------ > + > +Flow control can be enabled only on DPDK physical ports. To enable flow > +control support at Tx side while adding a port, run:: > + > + $ ovs-vsctl add-port br0 dpdk-p0 -- set Interface dpdk-p0 type=dpdk \ > + options:dpdk-devargs=0000:01:00.0 options:tx-flow-ctrl=true > + > +Similarly, to enable Rx flow control, run:: > + > + $ ovs-vsctl add-port br0 dpdk-p0 -- set Interface dpdk-p0 type=dpdk \ > + options:dpdk-devargs=0000:01:00.0 options:rx-flow-ctrl=true > + > +To enable flow control auto-negotiation, run:: > + > + $ ovs-vsctl add-port br0 dpdk-p0 -- set Interface dpdk-p0 type=dpdk \ > + options:dpdk-devargs=0000:01:00.0 > + options:flow-ctrl-autoneg=true > + > +To turn on the Tx flow control at run time for an existing port, run:: > + > + $ ovs-vsctl set Interface dpdk-p0 options:tx-flow-ctrl=true > + > +The flow control parameters can be turned off by setting ``false`` to > +the respective parameter. To disable the flow control at Tx side, run:: > + > + $ ovs-vsctl set Interface dpdk-p0 options:tx-flow-ctrl=false > + > +Rx Checksum Offload > +------------------- > + > +By default, DPDK physical ports are enabled with Rx checksum offload. > + > +Rx checksum offload can offer performance improvement only for > +tunneling traffic in OVS-DPDK because the checksum validation of tunnel > +packets is offloaded to the NIC. Also enabling Rx checksum may slightly > +reduce the performance of non-tunnel traffic, specifically for smaller > size packet. > + > +.. _port-hotplug: > + > +Hotplugging > +----------- > + > +OVS supports port hotplugging, allowing the use of physical ports that > +were not bound to DPDK when ovs-vswitchd was started. > + > +.. warning:: > + > + This feature is not compatible with all NICs. Refer to vendor > documentation > + for more information. > + > +.. important:: > + > + Ports must be bound to DPDK. Refer to :ref:`dpdk-binding-nics` for > more > + information. > + > +To *hotplug* a port, simply add it like any other port:: > + > + $ ovs-vsctl add-port br0 dpdkx -- set Interface dpdkx type=dpdk \ > + options:dpdk-devargs=0000:01:00.0 > + > +Ports can be detached using the ``del-port`` command:: > + > + $ ovs-vsctl del-port dpdkx > + > +This should both delete the port and detach the device. If successful, > +you should see an ``INFO`` log. For example:: > + > + INFO|Device '0000:04:00.1' has been detached > + > +If the log is not seen then the port can be detached like so:: > + > + $ ovs-appctl netdev-dpdk/detach 0000:01:00.0 > + > +.. warning:: > + > + Detaching should not be done if a device is known to be non- > detachable, as > + this may cause the device to behave improperly when added back with > + add-port. The Chelsio Terminator adapters which use the cxgbe driver > seem > + to be an example of this behavior; check the driver documentation if > this > + is suspected. > + > +For more information please refer to the `DPDK Port Hotplug Framework`__. > + > +__ > +http://dpdk.org/doc/guides/prog_guide/port_hotplug_framework.html#hotpl > +ug > -- > 2.14.3 _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
