1.. SPDX-License-Identifier: GPL-2.0 2 3========================= 4TC queue based filtering 5========================= 6 7TC can be used for directing traffic to either a set of queues or 8to a single queue on both the transmit and receive side. 9 10On the transmit side: 11 121) TC filter directing traffic to a set of queues is achieved 13 using the action skbedit priority for Tx priority selection, 14 the priority maps to a traffic class (set of queues) when 15 the queue-sets are configured using mqprio. 16 172) TC filter directs traffic to a transmit queue with the action 18 skbedit queue_mapping $tx_qid. The action skbedit queue_mapping 19 for transmit queue is executed in software only and cannot be 20 offloaded. 21 22Likewise, on the receive side, the two filters for selecting set of 23queues and/or a single queue are supported as below: 24 251) TC flower filter directs incoming traffic to a set of queues using 26 the 'hw_tc' option. 27 hw_tc $TCID - Specify a hardware traffic class to pass matching 28 packets on to. TCID is in the range 0 through 15. 29 302) TC filter with action skbedit queue_mapping $rx_qid selects a 31 receive queue. The action skbedit queue_mapping for receive queue 32 is supported only in hardware. Multiple filters may compete in 33 the hardware for queue selection. In such case, the hardware 34 pipeline resolves conflicts based on priority. On Intel E810 35 devices, TC filter directing traffic to a queue have higher 36 priority over flow director filter assigning a queue. The hash 37 filter has lowest priority. 38