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>

1 files changed, 95 insertions, 0 deletions

diff --git a/include/uapi/linux/net_shaper.h b/include/uapi/linux/net_shaper.h
new file mode 100644
index 000000000000..d8834b59f7d7
--- /dev/null
+++ b/include/uapi/linux/net_shaper.h
@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */
+/* Do not edit directly, auto-generated from: */
+/*	Documentation/netlink/specs/net_shaper.yaml */
+/* YNL-GEN uapi header */
+
+#ifndef _UAPI_LINUX_NET_SHAPER_H
+#define _UAPI_LINUX_NET_SHAPER_H
+
+#define NET_SHAPER_FAMILY_NAME		"net-shaper"
+#define NET_SHAPER_FAMILY_VERSION	1
+
+/**
+ * enum net_shaper_scope - Defines the shaper @id interpretation.
+ * @NET_SHAPER_SCOPE_UNSPEC: The scope is not specified.
+ * @NET_SHAPER_SCOPE_NETDEV: The main shaper for the given network device.
+ * @NET_SHAPER_SCOPE_QUEUE: The shaper is attached to the given device queue,
+ *   the @id represents the queue number.
+ * @NET_SHAPER_SCOPE_NODE: The shaper allows grouping of queues or other node
+ *   shapers; can be nested in either @netdev shapers or other @node shapers,
+ *   allowing placement in any location of the scheduling tree, except leaves
+ *   and root.
+ */
+enum net_shaper_scope {
+	NET_SHAPER_SCOPE_UNSPEC,
+	NET_SHAPER_SCOPE_NETDEV,
+	NET_SHAPER_SCOPE_QUEUE,
+	NET_SHAPER_SCOPE_NODE,
+
+	/* private: */
+	__NET_SHAPER_SCOPE_MAX,
+	NET_SHAPER_SCOPE_MAX = (__NET_SHAPER_SCOPE_MAX - 1)
+};
+
+/**
+ * enum net_shaper_metric - Different metric supported by the shaper.
+ * @NET_SHAPER_METRIC_BPS: Shaper operates on a bits per second basis.
+ * @NET_SHAPER_METRIC_PPS: Shaper operates on a packets per second basis.
+ */
+enum net_shaper_metric {
+	NET_SHAPER_METRIC_BPS,
+	NET_SHAPER_METRIC_PPS,
+};
+
+enum {
+	NET_SHAPER_A_HANDLE = 1,
+	NET_SHAPER_A_METRIC,
+	NET_SHAPER_A_BW_MIN,
+	NET_SHAPER_A_BW_MAX,
+	NET_SHAPER_A_BURST,
+	NET_SHAPER_A_PRIORITY,
+	NET_SHAPER_A_WEIGHT,
+	NET_SHAPER_A_IFINDEX,
+	NET_SHAPER_A_PARENT,
+	NET_SHAPER_A_LEAVES,
+
+	__NET_SHAPER_A_MAX,
+	NET_SHAPER_A_MAX = (__NET_SHAPER_A_MAX - 1)
+};
+
+enum {
+	NET_SHAPER_A_HANDLE_SCOPE = 1,
+	NET_SHAPER_A_HANDLE_ID,
+
+	__NET_SHAPER_A_HANDLE_MAX,
+	NET_SHAPER_A_HANDLE_MAX = (__NET_SHAPER_A_HANDLE_MAX - 1)
+};
+
+enum {
+	NET_SHAPER_A_CAPS_IFINDEX = 1,
+	NET_SHAPER_A_CAPS_SCOPE,
+	NET_SHAPER_A_CAPS_SUPPORT_METRIC_BPS,
+	NET_SHAPER_A_CAPS_SUPPORT_METRIC_PPS,
+	NET_SHAPER_A_CAPS_SUPPORT_NESTING,
+	NET_SHAPER_A_CAPS_SUPPORT_BW_MIN,
+	NET_SHAPER_A_CAPS_SUPPORT_BW_MAX,
+	NET_SHAPER_A_CAPS_SUPPORT_BURST,
+	NET_SHAPER_A_CAPS_SUPPORT_PRIORITY,
+	NET_SHAPER_A_CAPS_SUPPORT_WEIGHT,
+
+	__NET_SHAPER_A_CAPS_MAX,
+	NET_SHAPER_A_CAPS_MAX = (__NET_SHAPER_A_CAPS_MAX - 1)
+};
+
+enum {
+	NET_SHAPER_CMD_GET = 1,
+	NET_SHAPER_CMD_SET,
+	NET_SHAPER_CMD_DELETE,
+	NET_SHAPER_CMD_GROUP,
+	NET_SHAPER_CMD_CAP_GET,
+
+	__NET_SHAPER_CMD_MAX,
+	NET_SHAPER_CMD_MAX = (__NET_SHAPER_CMD_MAX - 1)
+};
+
+#endif /* _UAPI_LINUX_NET_SHAPER_H */