Re: [PATCH v7 net-next] octeontx2-pf: add mqprio bandwidth offload for NIX TX schedulers

On 2026-08-11 at 14:20:50, Ratheesh Kannoth (rkannoth@marvell.com) wrote:

Add TC_SETUP_QDISC_MQPRIO handling to offload per-queue MDQ CIR/PIR
shaping for mqprio channel mode with TC_MQPRIO_SHAPER_BW_RATE. When
bandwidth offload is enabled, allocate one SMQ per non-QoS transmit
queue, parent all MDQs under TL4[0], and program min/max rates by
dividing each traffic class byte/s limit across its queues.

Setting up or tearing down the offload restarts the netdev via
ndo_stop()/ndo_open() to rebuild the TX scheduler hierarchy. That
clears carrier, tears down IRQ/NAPI and drops in-flight traffic; if
ndo_open() fails the interface is left administratively down. Offload
setup is rejected unless the interface is already running.

Reject incompatible configurations (HTB, PFC, XDP, SDP rep, missing
CIR+PIR support) and out-of-range rates. Validate queue mappings
against hw.non_qos_queues and reject per-TC rates smaller than the
queue count that integer division would truncate to zero. Track offload
state in mqprio_rate_limit instead of pfvf->flags to avoid races with
the mbox up-handler, skip spurious teardown on tc qdisc replace, and
clear all MDQ shapers before applying a new mapping so queues dropped
from a TC layout do not retain stale limits. Restore cached shapers
across routine netdev stop/open via otx2_mqprio_up().

Will address sashiko issues in v8

https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260811085050.3212280-1-rkannoth%40marvell.com

pw-bot: changes-requested