Add QOS example configuration along with tc-htb commands Signed-off-by: Hariprasad Kelam <hkelam@xxxxxxxxxxx> Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxx> --- .../ethernet/marvell/octeontx2.rst | 45 +++++++++++++++++++ 1 file changed, 45 insertions(+) diff --git a/Documentation/networking/device_drivers/ethernet/marvell/octeontx2.rst b/Documentation/networking/device_drivers/ethernet/marvell/octeontx2.rst index 5ba9015336e2..bfd233cfac35 100644 --- a/Documentation/networking/device_drivers/ethernet/marvell/octeontx2.rst +++ b/Documentation/networking/device_drivers/ethernet/marvell/octeontx2.rst @@ -13,6 +13,7 @@ Contents - `Drivers`_ - `Basic packet flow`_ - `Devlink health reporters`_ +- `Quality of service`_ Overview ======== @@ -287,3 +288,47 @@ For example:: NIX_AF_ERR: NIX Error Interrupt Reg : 64 Rx on unmapped PF_FUNC + + +Quality of service +================== + + +Hardware algorithms used in scheduling +-------------------------------------- + +octeontx2 silicon and CN10K transmit interface consists of five transmit levels +starting from SMQ/MDQ, TL4 to TL1. Each packet will traverse MDQ, TL4 to TL1 +levels. Each level contains an array of queues to support scheduling and shaping. +The hardware uses the below algorithms depending on the priority of scheduler queues. +once the usercreates tc classes with different priorities, the driver configures +schedulers allocated to the class with specified priority along with rate-limiting +configuration. + +1. Strict Priority + + - Once packets are submitted to MDQ, hardware picks all active MDQs having different priority + using strict priority. + +2. Round Robin + + - Active MDQs having the same priority level are chosen using round robin. + + +Setup HTB offload +----------------- + +1. Enable HW TC offload on the interface:: + + # ethtool -K <interface> hw-tc-offload on + +2. Crate htb root:: + + # tc qdisc add dev <interface> clsact + # tc qdisc replace dev <interface> root handle 1: htb offload + +3. Create tc classes with different priorities:: + + # tc class add dev <interface> parent 1: classid 1:1 htb rate 10Gbit prio 1 + + # tc class add dev <interface> parent 1: classid 1:2 htb rate 10Gbit prio 7 -- 2.17.1
