mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-27 12:57:53 +00:00
d5ae8ecf38
Add tc-queue-filters.rst with notes on TC filters for selecting a set of queues and/or a queue. Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
37 lines
1.5 KiB
ReStructuredText
37 lines
1.5 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0
|
|
|
|
=========================
|
|
TC queue based filtering
|
|
=========================
|
|
|
|
TC can be used for directing traffic to either a set of queues or
|
|
to a single queue on both the transmit and receive side.
|
|
|
|
On the transmit side:
|
|
|
|
1) TC filter directing traffic to a set of queues is achieved
|
|
using the action skbedit priority for Tx priority selection,
|
|
the priority maps to a traffic class (set of queues) when
|
|
the queue-sets are configured using mqprio.
|
|
|
|
2) TC filter directs traffic to a transmit queue with the action
|
|
skbedit queue_mapping $tx_qid. The action skbedit queue_mapping
|
|
for transmit queue is executed in software only and cannot be
|
|
offloaded.
|
|
|
|
Likewise, on the receive side, the two filters for selecting set of
|
|
queues and/or a single queue are supported as below:
|
|
|
|
1) TC flower filter directs incoming traffic to a set of queues using
|
|
the 'hw_tc' option.
|
|
hw_tc $TCID - Specify a hardware traffic class to pass matching
|
|
packets on to. TCID is in the range 0 through 15.
|
|
|
|
2) TC filter with action skbedit queue_mapping $rx_qid selects a
|
|
receive queue. The action skbedit queue_mapping for receive queue
|
|
is supported only in hardware. Multiple filters may compete in
|
|
the hardware for queue selection. In such case, the hardware
|
|
pipeline resolves conflicts based on priority. On Intel E810
|
|
devices, TC filter directing traffic to a queue have higher
|
|
priority over flow director filter assigning a queue. The hash
|
|
filter has lowest priority.
|