Commit 68db0ff2 authored by Chia-Yu Chang's avatar Chia-Yu Chang Committed by Jakub Kicinski
Browse files

Documentation: netlink: specs: tc: Add DualPI2 specification 

Introduce the specification of tc qdisc DualPI2 stats and attributes,
which is the reference implementation of IETF RFC9332 DualQ Coupled AQM
(https://datatracker.ietf.org/doc/html/rfc9332

) providing two different
queues: low latency queue (L-queue) and classic queue (C-queue).

Signed-off-by: default avatarChia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Link: https://patch.msgid.link/20250722095915.24485-7-chia-yu.chang@nokia-bell-labs.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 032f0e9e

Documentation/netlink/specs/tc.yaml

+149 −2
Original line number Diff line number Diff line
@@ -56,6 +56,23 @@ definitions: 
      - tundf

      - tunoam

      - tuncrit

  -

    name: dualpi2-drop-overload

    type: enum

    entries: [overflow, drop]

  -

    name: dualpi2-drop-early

    type: enum

    entries: [drop-dequeue, drop-enqueue]

  -

    name: dualpi2-ecn-mask

    type: enum

    value-start: 1

    entries: [l4s-ect, cla-ect, any-ect]

  -

    name: dualpi2-split-gso

    type: enum

    entries: [no-split-gso, split-gso]

  -

    name: tc-stats

    type: struct
@@ -825,6 +842,58 @@ definitions: 
      -

        name: drop-overmemory

        type: u32

  -

    name: tc-dualpi2-xstats

    type: struct

    members:

      -

        name: prob

        type: u32

        doc: Current base PI probability

      -

        name: delay-c

        type: u32

        doc: Current C-queue delay in microseconds

      -

        name: delay-l

        type: u32

        doc: Current L-queue delay in microseconds

      -

        name: pkts-in-c

        type: u32

        doc: Number of packets enqueued in the C-queue

      -

        name: pkts-in-l

        type: u32

        doc: Number of packets enqueued in the L-queue

      -

        name: maxq

        type: u32

        doc: Maximum number of packets seen by the DualPI2

      -

        name: ecn-mark

        type: u32

        doc: All packets marked with ECN

      -

        name: step-mark

        type: u32

        doc: Only packets marked with ECN due to L-queue step AQM

      -

        name: credit

        type: s32

        doc: Current credit value for WRR

      -

        name: memory-used

        type: u32

        doc: Memory used in bytes by the DualPI2

      -

        name: max-memory-used

        type: u32

        doc: Maximum memory used in bytes by the DualPI2

      -

        name: memory-limit

        type: u32

        doc: Memory limit in bytes

  -

    name: tc-fq-pie-xstats

    type: struct
@@ -848,7 +917,7 @@ definitions: 
      -

        name: ecn-mark

        type: u32

        doc: Packets marked with ecn

        doc: Packets marked with ECN

      -

        name: new-flow-count

        type: u32
@@ -991,7 +1060,7 @@ definitions: 
      -

        name: ecn-mark

        type: u32

        doc: Packets marked with ecn

        doc: Packets marked with ECN

  -

    name: tc-red-xstats

    type: struct
@@ -2284,6 +2353,78 @@ attribute-sets: 
      -

        name: quantum

        type: u32

  -

    name: dualpi2-attrs

    name-prefix: tca-dualpi2-

    attributes:

      -

        name: limit

        type: u32

        doc: Limit of total number of packets in queue

      -

        name: memory-limit

        type: u32

        doc: Memory limit of total number of packets in queue

      -

        name: target

        type: u32

        doc: Classic target delay in microseconds

      -

        name: tupdate

        type: u32

        doc: Drop probability update interval time in microseconds

      -

        name: alpha

        type: u32

        doc: Integral gain factor in Hz for PI controller

      -

        name: beta

        type: u32

        doc: Proportional gain factor in Hz for PI controller

      -

        name: step-thresh-pkts

        type: u32

        doc: L4S step marking threshold in packets

      -

        name: step-thresh-us

        type: u32

        doc: L4S Step marking threshold in microseconds

      -

        name: min-qlen-step

        type: u32

        doc: Packets enqueued to the L-queue can apply the step threshold

             when the queue length of L-queue is larger than this value.

             (0 is recommended)

      -

        name: coupling

        type: u8

        doc: Probability coupling factor between Classic and L4S

             (2 is recommended)

      -

        name: drop-overload

        type: u8

        doc: Control the overload strategy (drop to preserve latency or

             let the queue overflow)

        enum: dualpi2-drop-overload

      -

        name: drop-early

        type: u8

        doc: Decide where the Classic packets are PI-based dropped or marked

        enum: dualpi2-drop-early

      -

        name: c-protection

        type: u8

        doc: Classic WRR weight in percentage (from 0 to 100)

      -

        name: ecn-mask

        type: u8

        doc: Configure the L-queue ECN classifier

        enum: dualpi2-ecn-mask

      -

        name: split-gso

        type: u8

        doc: Split aggregated skb or not

        enum: dualpi2-split-gso

  -

    name: ematch-attrs

    name-prefix: tca-ematch-
@@ -3708,6 +3849,9 @@ sub-messages: 
      -

        value: drr

        attribute-set: drr-attrs

      -

        value: dualpi2

        attribute-set: dualpi2-attrs

      -

        value: etf

        attribute-set: etf-attrs
@@ -3875,6 +4019,9 @@ sub-messages: 
      -

        value: codel

        fixed-header: tc-codel-xstats

      -

        value: dualpi2

        fixed-header: tc-dualpi2-xstats

      -

        value: fq

        fixed-header: tc-fq-qd-stats