netdev_dpdk.c: Add QoS functionality.

This patch provides the modifications required in netdev-dpdk.c and
vswitch.xml to allow for a DPDK user space QoS algorithm.

This patch adds a QoS configuration structure for netdev-dpdk and
expected QoS operations 'dpdk_qos_ops'. Various helper functions
are also supplied.

Also included are the modifications required for vswitch.xml to allow a
new QoS implementation for netdev-dpdk devices. This includes a new QoS type
`egress-policer` as well as its expected QoS table entries.

The QoS functionality implemented for DPDK devices is `egress-policer`.
This can be used to drop egress packets at a configurable rate.

The INSTALL.DPDK.md guide has also been modified to provide an example
configuration of `egress-policer` QoS.

Signed-off-by: Ian Stokes <ian.stokes@intel.com>
Acked-by: Flavio Leitner <fbl@sysclose.org>
Acked-by: Daniele Di Proietto <diproiettod@vmware.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/INSTALL.DPDK.md b/INSTALL.DPDK.md
index dca79bd35..b33f75e3c 100644
--- a/INSTALL.DPDK.md
+++ b/INSTALL.DPDK.md
@@ -207,6 +207,26 @@ Using the DPDK with ovs-vswitchd:
    ./ovs-ofctl add-flow br0 in_port=2,action=output:1
    ```
 
+8. QoS usage example
+
+   Assuming you have a vhost-user port transmitting traffic consisting of
+   packets of size 64 bytes, the following command would limit the egress
+   transmission rate of the port to ~1,000,000 packets per second:
+
+   `ovs-vsctl set port vhost-user0 qos=@newqos -- --id=@newqos create qos
+   type=egress-policer other-config:cir=46000000 other-config:cbs=2048`
+
+   To examine the QoS configuration of the port:
+
+   `ovs-appctl -t ovs-vswitchd qos/show vhost-user0`
+
+   To clear the QoS configuration from the port and ovsdb use the following:
+
+   `ovs-vsctl destroy QoS vhost-user0 -- clear Port vhost-user0 qos`
+
+   For more details regarding egress-policer parameters please refer to the
+   vswitch.xml.
+
 Performance Tuning:
 -------------------