Merge branch 'net-introduce-tx-h-w-shaping-api'

Paolo Abeni says:

====================
net: introduce TX H/W shaping API

We have a plurality of shaping-related drivers API, but none flexible
enough to meet existing demand from vendors[1].

This series introduces new device APIs to configure in a flexible way
TX H/W shaping. The new functionalities are exposed via a newly
defined generic netlink interface and include introspection
capabilities. Some self-tests are included, on top of a dummy
netdevsim implementation. Finally a basic implementation for the iavf
driver is provided.

Some usage examples:

* Configure shaping on a given queue:

./tools/net/ynl/cli.py --spec Documentation/netlink/specs/shaper.yaml \
	--do set --json '{"ifindex": '$IFINDEX',
			  "shaper": {"handle":
				     {"scope": "queue", "id":'$QUEUEID'},
			  "bw-max": 2000000}}'

* Container B/W sharing

The orchestration infrastructure wants to group the
container-related queues under a RR scheduling and limit the aggregate
bandwidth:

./tools/net/ynl/cli.py --spec Documentation/netlink/specs/shaper.yaml \
	--do group --json '{"ifindex": '$IFINDEX',
			"leaves": [
			  {"handle": {"scope": "queue", "id":'$QID1'},
			   "weight": '$W1'},
			  {"handle": {"scope": "queue", "id":'$QID2'},
			   "weight": '$W2'}],
			  {"handle": {"scope": "queue", "id":'$QID3'},
			   "weight": '$W3'}],
			"handle": {"scope":"node"},
			"bw-max": 10000000}'
{'ifindex': $IFINDEX, 'handle': {'scope': 'node', 'id': 0}}

Q1 \
    \
Q2 -- node 0 -------  netdev
    / (bw-max: 10M)
Q3 /

* Delegation

A containers wants to limit the aggregate B/W bandwidth of 2 of the 3
queues it owns - the starting configuration is the one from the
previous point:

SPEC=Documentation/netlink/specs/net_shaper.yaml
./tools/net/ynl/cli.py --spec $SPEC \
	--do group --json '{"ifindex": '$IFINDEX',
			"leaves": [
			  {"handle": {"scope": "queue", "id":'$QID1'},
			   "weight": '$W1'},
			  {"handle": {"scope": "queue", "id":'$QID2'},
			   "weight": '$W2'}],
			"handle": {"scope": "node"},
			"bw-max": 5000000 }'
{'ifindex': $IFINDEX, 'handle': {'scope': 'node', 'id': 1}}

Q1 -- node 1 --------\
    / (bw-max: 5M)    \
Q2 /                   node 0 -------  netdev
                      /(bw-max: 10M)
Q3 ------------------/

In a group operation, when prior to the op itself, the leaves have
different parents, the user must specify the parent handle for the
group. I.e., starting from the previous config:

./tools/net/ynl/cli.py --spec $SPEC \
	--do group --json '{"ifindex": '$IFINDEX',
			"leaves": [
			  {"handle": {"scope": "queue", "id":'$QID1'},
			   "weight": '$W1'},
			  {"handle": {"scope": "queue", "id":'$QID3'},
			   "weight": '$W3'}],
			"handle": {"scope": "node"},
			"bw-max": 3000000 }'
Netlink error: Invalid argument
nl_len = 96 (80) nl_flags = 0x300 nl_type = 2
	error: -22
	extack: {'msg': 'All the leaves shapers must have the same old parent'}

./tools/net/ynl/cli.py --spec $SPEC \
	--do group --json '{"ifindex": '$IFINDEX',
			"leaves": [
			  {"handle": {"scope": "queue", "id":'$QID1'},
			   "weight": '$W1'},
			  {"handle": {"scope": "queue", "id":'$QID3'},
			   "weight": '$W3'}],
			"handle": {"scope": "node"},
			"parent": {"scope": "node", "id": 1},
			"bw-max": 3000000 }
{'ifindex': $IFINDEX, 'handle': {'scope': 'node', 'id': 2}}

Q1 -- node 2 ---
    /(bw-max:3M)\
Q3 /             \
         ---- node 1 \
        / (bw-max: 5M)\
      Q2              node 0 -------  netdev
                      (bw-max: 10M)

* Cleanup:

Still starting from config 1To delete a single queue shaper

./tools/net/ynl/cli.py --spec $SPEC --do delete --json \
	'{"ifindex": '$IFINDEX',
	  "handle": {"scope": "queue", "id":'$QID3'}}'

Q1 -- node 2 ---
     (bw-max:3M)\
                 \
         ---- node 1 \
        / (bw-max: 5M)\
      Q2              node 0 -------  netdev
                      (bw-max: 10M)

Deleting a node shaper relinks all its leaves to the node's parent:

./tools/net/ynl/cli.py --spec $SPEC --do delete --json \
	'{"ifindex": '$IFINDEX',
	  "handle": {"scope": "node", "id":2}}'

Q1 ---\
       \
        node 1----- \
       / (bw-max: 5M)\
Q2----/              node 0 -------  netdev
                     (bw-max: 10M)

Deleting the last shaper under a node shaper deletes the node, too:

./tools/net/ynl/cli.py --spec $SPEC --do delete --json \
	'{"ifindex": '$IFINDEX',
	  "handle": {"scope": "queue", "id":'$QID1'}}'
./tools/net/ynl/cli.py --spec $SPEC --do delete --json \
	'{"ifindex": '$IFINDEX',
	  "handle": {"scope": "queue", "id":'$QID2'}}'
./tools/net/ynl/cli.py --spec $SPEC --do get --json \
	'{"ifindex": '$IFINDEX',
	  "handle": {"scope": "node", "id": 1}}'
Netlink error: No such file or directory
nl_len = 44 (28) nl_flags = 0x300 nl_type = 2
	error: -2
	extack: {'bad-attr': '.handle'}

Such delete recurses on parents that are left over with no leaves:

./tools/net/ynl/cli.py --spec $SPEC --do get --json \
	'{"ifindex": '$IFINDEX',
	  "handle": {"scope": "node", "id": 0}}'
Netlink error: No such file or directory
nl_len = 44 (28) nl_flags = 0x300 nl_type = 2
	error: -2
	extack: {'bad-attr': '.handle'}

v8: https://lore.kernel.org/cover.1727704215.git.pabeni@redhat.com
v7: https://lore.kernel.org/cover.1725919039.git.pabeni@redhat.com
v6: https://lore.kernel.org/cover.1725457317.git.pabeni@redhat.com
v5: https://lore.kernel.org/cover.1724944116.git.pabeni@redhat.com
v4: https://lore.kernel.org/cover.1724165948.git.pabeni@redhat.com
v3: https://lore.kernel.org/cover.1722357745.git.pabeni@redhat.com
RFC v2: https://lore.kernel.org/cover.1721851988.git.pabeni@redhat.com
RFC v1: https://lore.kernel.org/cover.1719518113.git.pabeni@redhat.com
====================

Link: https://patch.msgid.link/cover.1728460186.git.pabeni@redhat.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>