]> git.ipfire.org Git - thirdparty/kernel/stable.git/commitdiff
devlink: Extend devlink rate API with traffic classes bandwidth management
authorCarolina Jubran <cjubran@nvidia.com>
Sun, 29 Jun 2025 14:21:32 +0000 (17:21 +0300)
committerJakub Kicinski <kuba@kernel.org>
Wed, 2 Jul 2025 22:39:05 +0000 (15:39 -0700)
Introduce support for specifying relative bandwidth shares between
traffic classes (TC) in the devlink-rate API. This new option allows
users to allocate bandwidth across multiple traffic classes in a
single command.

This feature provides a more granular control over traffic management,
especially for scenarios requiring Enhanced Transmission Selection.

Users can now define a relative bandwidth share for each traffic class.
For example, assigning share values of 20 to TC0 (TCP/UDP) and 80 to TC5
(RoCE) will result in TC0 receiving 20% and TC5 receiving 80% of the
total bandwidth. The actual percentage each class receives depends on
the ratio of its share value to the sum of all shares.

Example:
DEV=pci/0000:08:00.0

$ devlink port function rate add $DEV/vfs_group tx_share 10Gbit \
  tx_max 50Gbit tc-bw 0:20 1:0 2:0 3:0 4:0 5:80 6:0 7:0

$ devlink port function rate set $DEV/vfs_group \
  tc-bw 0:20 1:0 2:0 3:0 4:0 5:20 6:60 7:0

Example usage with ynl:

./tools/net/ynl/cli.py --spec Documentation/netlink/specs/devlink.yaml \
  --do rate-set --json '{
  "bus-name": "pci",
  "dev-name": "0000:08:00.0",
  "port-index": 1,
  "rate-tc-bws": [
    {"rate-tc-index": 0, "rate-tc-bw": 50},
    {"rate-tc-index": 1, "rate-tc-bw": 50},
    {"rate-tc-index": 2, "rate-tc-bw": 0},
    {"rate-tc-index": 3, "rate-tc-bw": 0},
    {"rate-tc-index": 4, "rate-tc-bw": 0},
    {"rate-tc-index": 5, "rate-tc-bw": 0},
    {"rate-tc-index": 6, "rate-tc-bw": 0},
    {"rate-tc-index": 7, "rate-tc-bw": 0}
  ]
}'

./tools/net/ynl/cli.py --spec Documentation/netlink/specs/devlink.yaml \
  --do rate-get --json '{
  "bus-name": "pci",
  "dev-name": "0000:08:00.0",
  "port-index": 1
}'

output for rate-get:
{'bus-name': 'pci',
 'dev-name': '0000:08:00.0',
 'port-index': 1,
 'rate-tc-bws': [{'rate-tc-bw': 50, 'rate-tc-index': 0},
                 {'rate-tc-bw': 50, 'rate-tc-index': 1},
                 {'rate-tc-bw': 0, 'rate-tc-index': 2},
                 {'rate-tc-bw': 0, 'rate-tc-index': 3},
                 {'rate-tc-bw': 0, 'rate-tc-index': 4},
                 {'rate-tc-bw': 0, 'rate-tc-index': 5},
                 {'rate-tc-bw': 0, 'rate-tc-index': 6},
                 {'rate-tc-bw': 0, 'rate-tc-index': 7}],
 'rate-tx-max': 0,
 'rate-tx-priority': 0,
 'rate-tx-share': 0,
 'rate-tx-weight': 0,
 'rate-type': 'leaf'}

Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Link: https://patch.msgid.link/20250629142138.361537-3-mbloch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Documentation/netlink/specs/devlink.yaml
Documentation/networking/devlink/devlink-port.rst
include/net/devlink.h
include/uapi/linux/devlink.h
net/devlink/netlink_gen.c
net/devlink/netlink_gen.h
net/devlink/rate.c

index bfba466d694ad38dbe6f6ec00ef668581db9c682..1c4bb0cbe5f0998b3eb64b5b24ea85a1a923daaa 100644 (file)
@@ -224,6 +224,10 @@ definitions:
         value: 10
       -
         name: binary
+  -
+    name: rate-tc-index-max
+    type: const
+    value: 7
 
 attribute-sets:
   -
@@ -844,7 +848,23 @@ attribute-sets:
       -
         name: region-direct
         type: flag
-
+      -
+        name: rate-tc-bws
+        type: nest
+        multi-attr: true
+        nested-attributes: dl-rate-tc-bws
+      -
+        name: rate-tc-index
+        type: u8
+        checks:
+          max: rate-tc-index-max
+      -
+        name: rate-tc-bw
+        type: u32
+        doc: |
+             Specifies the bandwidth share assigned to the Traffic Class.
+             The bandwidth for the traffic class is determined
+             in proportion to the sum of the shares of all configured classes.
   -
     name: dl-dev-stats
     subset-of: devlink
@@ -1249,6 +1269,14 @@ attribute-sets:
       -
         name: flash
         type: flag
+  -
+    name: dl-rate-tc-bws
+    subset-of: devlink
+    attributes:
+      -
+        name: rate-tc-index
+      -
+        name: rate-tc-bw
 
 operations:
   enum-model: directional
@@ -2176,6 +2204,7 @@ operations:
             - rate-tx-priority
             - rate-tx-weight
             - rate-parent-node-name
+            - rate-tc-bws
 
     -
       name: rate-new
@@ -2196,6 +2225,7 @@ operations:
             - rate-tx-priority
             - rate-tx-weight
             - rate-parent-node-name
+            - rate-tc-bws
 
     -
       name: rate-del
index 9d22d41a7cd15986249d87a5c32ea3a67e4ab9e1..5e397798a40224754258f706272db229f1398775 100644 (file)
@@ -418,6 +418,14 @@ API allows to configure following rate object's parameters:
   to all node children limits. ``tx_max`` is an upper limit for children.
   ``tx_share`` is a total bandwidth distributed among children.
 
+``tc_bw``
+  Allow users to set the bandwidth allocation per traffic class on rate
+  objects. This enables fine-grained QoS configurations by assigning a relative
+  share value to each traffic class. The bandwidth is distributed in proportion
+  to the share value for each class, relative to the sum of all shares.
+  When applied to a non-leaf node, tc_bw determines how bandwidth is shared
+  among its child elements.
+
 ``tx_priority`` and ``tx_weight`` can be used simultaneously. In that case
 nodes with the same priority form a WFQ subgroup in the sibling group
 and arbitration among them is based on assigned weights.
index 63517646a497306f15565c44a5049a4cb8926d0b..d0ce5a7e984c53db7f4cc0513452ad1279574c08 100644 (file)
@@ -118,6 +118,8 @@ struct devlink_rate {
 
        u32 tx_priority;
        u32 tx_weight;
+
+       u32 tc_bw[DEVLINK_RATE_TCS_MAX];
 };
 
 struct devlink_port {
@@ -1486,6 +1488,9 @@ struct devlink_ops {
                                         u32 tx_priority, struct netlink_ext_ack *extack);
        int (*rate_leaf_tx_weight_set)(struct devlink_rate *devlink_rate, void *priv,
                                       u32 tx_weight, struct netlink_ext_ack *extack);
+       int (*rate_leaf_tc_bw_set)(struct devlink_rate *devlink_rate,
+                                  void *priv, u32 *tc_bw,
+                                  struct netlink_ext_ack *extack);
        int (*rate_node_tx_share_set)(struct devlink_rate *devlink_rate, void *priv,
                                      u64 tx_share, struct netlink_ext_ack *extack);
        int (*rate_node_tx_max_set)(struct devlink_rate *devlink_rate, void *priv,
@@ -1494,6 +1499,9 @@ struct devlink_ops {
                                         u32 tx_priority, struct netlink_ext_ack *extack);
        int (*rate_node_tx_weight_set)(struct devlink_rate *devlink_rate, void *priv,
                                       u32 tx_weight, struct netlink_ext_ack *extack);
+       int (*rate_node_tc_bw_set)(struct devlink_rate *devlink_rate,
+                                  void *priv, u32 *tc_bw,
+                                  struct netlink_ext_ack *extack);
        int (*rate_node_new)(struct devlink_rate *rate_node, void **priv,
                             struct netlink_ext_ack *extack);
        int (*rate_node_del)(struct devlink_rate *rate_node, void *priv,
index a5ee0f13740ab112986a86a2ae9f2d7897c32c50..e72bcc239afd6b098e047bd660d5b4735e9e9fcc 100644 (file)
@@ -221,6 +221,11 @@ enum devlink_port_flavour {
                                      */
 };
 
+/* IEEE 802.1Qaz standard supported values. */
+
+#define DEVLINK_RATE_TCS_MAX 8
+#define DEVLINK_RATE_TC_INDEX_MAX (DEVLINK_RATE_TCS_MAX - 1)
+
 enum devlink_rate_type {
        DEVLINK_RATE_TYPE_LEAF,
        DEVLINK_RATE_TYPE_NODE,
@@ -629,6 +634,10 @@ enum devlink_attr {
 
        DEVLINK_ATTR_REGION_DIRECT,             /* flag */
 
+       DEVLINK_ATTR_RATE_TC_BWS,               /* nested */
+       DEVLINK_ATTR_RATE_TC_INDEX,             /* u8 */
+       DEVLINK_ATTR_RATE_TC_BW,                /* u32 */
+
        /* Add new attributes above here, update the spec in
         * Documentation/netlink/specs/devlink.yaml and re-generate
         * net/devlink/netlink_gen.c.
index e340d955cf3bce69c031325a2af25ec6fe2a6adc..c50436433c187c7342f8252d32e0a50ead08580f 100644 (file)
@@ -45,6 +45,11 @@ const struct nla_policy devlink_dl_port_function_nl_policy[DEVLINK_PORT_FN_ATTR_
        [DEVLINK_PORT_FN_ATTR_CAPS] = NLA_POLICY_BITFIELD32(15),
 };
 
+const struct nla_policy devlink_dl_rate_tc_bws_nl_policy[DEVLINK_ATTR_RATE_TC_BW + 1] = {
+       [DEVLINK_ATTR_RATE_TC_INDEX] = NLA_POLICY_MAX(NLA_U8, DEVLINK_RATE_TC_INDEX_MAX),
+       [DEVLINK_ATTR_RATE_TC_BW] = { .type = NLA_U32, },
+};
+
 const struct nla_policy devlink_dl_selftest_id_nl_policy[DEVLINK_ATTR_SELFTEST_ID_FLASH + 1] = {
        [DEVLINK_ATTR_SELFTEST_ID_FLASH] = { .type = NLA_FLAG, },
 };
@@ -523,7 +528,7 @@ static const struct nla_policy devlink_rate_get_dump_nl_policy[DEVLINK_ATTR_DEV_
 };
 
 /* DEVLINK_CMD_RATE_SET - do */
-static const struct nla_policy devlink_rate_set_nl_policy[DEVLINK_ATTR_RATE_TX_WEIGHT + 1] = {
+static const struct nla_policy devlink_rate_set_nl_policy[DEVLINK_ATTR_RATE_TC_BWS + 1] = {
        [DEVLINK_ATTR_BUS_NAME] = { .type = NLA_NUL_STRING, },
        [DEVLINK_ATTR_DEV_NAME] = { .type = NLA_NUL_STRING, },
        [DEVLINK_ATTR_RATE_NODE_NAME] = { .type = NLA_NUL_STRING, },
@@ -532,10 +537,11 @@ static const struct nla_policy devlink_rate_set_nl_policy[DEVLINK_ATTR_RATE_TX_W
        [DEVLINK_ATTR_RATE_TX_PRIORITY] = { .type = NLA_U32, },
        [DEVLINK_ATTR_RATE_TX_WEIGHT] = { .type = NLA_U32, },
        [DEVLINK_ATTR_RATE_PARENT_NODE_NAME] = { .type = NLA_NUL_STRING, },
+       [DEVLINK_ATTR_RATE_TC_BWS] = NLA_POLICY_NESTED(devlink_dl_rate_tc_bws_nl_policy),
 };
 
 /* DEVLINK_CMD_RATE_NEW - do */
-static const struct nla_policy devlink_rate_new_nl_policy[DEVLINK_ATTR_RATE_TX_WEIGHT + 1] = {
+static const struct nla_policy devlink_rate_new_nl_policy[DEVLINK_ATTR_RATE_TC_BWS + 1] = {
        [DEVLINK_ATTR_BUS_NAME] = { .type = NLA_NUL_STRING, },
        [DEVLINK_ATTR_DEV_NAME] = { .type = NLA_NUL_STRING, },
        [DEVLINK_ATTR_RATE_NODE_NAME] = { .type = NLA_NUL_STRING, },
@@ -544,6 +550,7 @@ static const struct nla_policy devlink_rate_new_nl_policy[DEVLINK_ATTR_RATE_TX_W
        [DEVLINK_ATTR_RATE_TX_PRIORITY] = { .type = NLA_U32, },
        [DEVLINK_ATTR_RATE_TX_WEIGHT] = { .type = NLA_U32, },
        [DEVLINK_ATTR_RATE_PARENT_NODE_NAME] = { .type = NLA_NUL_STRING, },
+       [DEVLINK_ATTR_RATE_TC_BWS] = NLA_POLICY_NESTED(devlink_dl_rate_tc_bws_nl_policy),
 };
 
 /* DEVLINK_CMD_RATE_DEL - do */
@@ -1191,7 +1198,7 @@ const struct genl_split_ops devlink_nl_ops[74] = {
                .doit           = devlink_nl_rate_set_doit,
                .post_doit      = devlink_nl_post_doit,
                .policy         = devlink_rate_set_nl_policy,
-               .maxattr        = DEVLINK_ATTR_RATE_TX_WEIGHT,
+               .maxattr        = DEVLINK_ATTR_RATE_TC_BWS,
                .flags          = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
        },
        {
@@ -1201,7 +1208,7 @@ const struct genl_split_ops devlink_nl_ops[74] = {
                .doit           = devlink_nl_rate_new_doit,
                .post_doit      = devlink_nl_post_doit,
                .policy         = devlink_rate_new_nl_policy,
-               .maxattr        = DEVLINK_ATTR_RATE_TX_WEIGHT,
+               .maxattr        = DEVLINK_ATTR_RATE_TC_BWS,
                .flags          = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
        },
        {
index 8f2bd50ddf5e2774b23860130502d05bd38a9414..fb733b5d4ff1da2675b34071a9d9a2fd822f3e81 100644 (file)
@@ -13,6 +13,7 @@
 
 /* Common nested types */
 extern const struct nla_policy devlink_dl_port_function_nl_policy[DEVLINK_PORT_FN_ATTR_CAPS + 1];
+extern const struct nla_policy devlink_dl_rate_tc_bws_nl_policy[DEVLINK_ATTR_RATE_TC_BW + 1];
 extern const struct nla_policy devlink_dl_selftest_id_nl_policy[DEVLINK_ATTR_SELFTEST_ID_FLASH + 1];
 
 /* Ops table for devlink */
index 8828ffaf6cbc0372115674e52d754bd9ed65dca9..d39300a9b3d4184bd7c10eeb938f98aea10543d7 100644 (file)
@@ -80,6 +80,29 @@ devlink_rate_get_from_info(struct devlink *devlink, struct genl_info *info)
                return ERR_PTR(-EINVAL);
 }
 
+static int devlink_rate_put_tc_bws(struct sk_buff *msg, u32 *tc_bw)
+{
+       struct nlattr *nla_tc_bw;
+       int i;
+
+       for (i = 0; i < DEVLINK_RATE_TCS_MAX; i++) {
+               nla_tc_bw = nla_nest_start(msg, DEVLINK_ATTR_RATE_TC_BWS);
+               if (!nla_tc_bw)
+                       return -EMSGSIZE;
+
+               if (nla_put_u8(msg, DEVLINK_ATTR_RATE_TC_INDEX, i) ||
+                   nla_put_u32(msg, DEVLINK_ATTR_RATE_TC_BW, tc_bw[i]))
+                       goto nla_put_failure;
+
+               nla_nest_end(msg, nla_tc_bw);
+       }
+       return 0;
+
+nla_put_failure:
+       nla_nest_cancel(msg, nla_tc_bw);
+       return -EMSGSIZE;
+}
+
 static int devlink_nl_rate_fill(struct sk_buff *msg,
                                struct devlink_rate *devlink_rate,
                                enum devlink_command cmd, u32 portid, u32 seq,
@@ -129,6 +152,9 @@ static int devlink_nl_rate_fill(struct sk_buff *msg,
                                   devlink_rate->parent->name))
                        goto nla_put_failure;
 
+       if (devlink_rate_put_tc_bws(msg, devlink_rate->tc_bw))
+               goto nla_put_failure;
+
        genlmsg_end(msg, hdr);
        return 0;
 
@@ -316,6 +342,87 @@ devlink_nl_rate_parent_node_set(struct devlink_rate *devlink_rate,
        return 0;
 }
 
+static int devlink_nl_rate_tc_bw_parse(struct nlattr *parent_nest, u32 *tc_bw,
+                                      unsigned long *bitmap,
+                                      struct netlink_ext_ack *extack)
+{
+       struct nlattr *tb[DEVLINK_ATTR_MAX + 1];
+       u8 tc_index;
+       int err;
+
+       err = nla_parse_nested(tb, DEVLINK_ATTR_MAX, parent_nest,
+                              devlink_dl_rate_tc_bws_nl_policy, extack);
+       if (err)
+               return err;
+
+       if (!tb[DEVLINK_ATTR_RATE_TC_INDEX]) {
+               NL_SET_ERR_ATTR_MISS(extack, parent_nest,
+                                    DEVLINK_ATTR_RATE_TC_INDEX);
+               return -EINVAL;
+       }
+
+       tc_index = nla_get_u8(tb[DEVLINK_ATTR_RATE_TC_INDEX]);
+
+       if (!tb[DEVLINK_ATTR_RATE_TC_BW]) {
+               NL_SET_ERR_ATTR_MISS(extack, parent_nest,
+                                    DEVLINK_ATTR_RATE_TC_BW);
+               return -EINVAL;
+       }
+
+       if (test_and_set_bit(tc_index, bitmap)) {
+               NL_SET_ERR_MSG_FMT(extack,
+                                  "Duplicate traffic class index specified (%u)",
+                                  tc_index);
+               return -EINVAL;
+       }
+
+       tc_bw[tc_index] = nla_get_u32(tb[DEVLINK_ATTR_RATE_TC_BW]);
+
+       return 0;
+}
+
+static int devlink_nl_rate_tc_bw_set(struct devlink_rate *devlink_rate,
+                                    struct genl_info *info)
+{
+       DECLARE_BITMAP(bitmap, DEVLINK_RATE_TCS_MAX) = {};
+       struct devlink *devlink = devlink_rate->devlink;
+       const struct devlink_ops *ops = devlink->ops;
+       u32 tc_bw[DEVLINK_RATE_TCS_MAX] = {};
+       int rem, err = -EOPNOTSUPP, i;
+       struct nlattr *attr;
+
+       nlmsg_for_each_attr_type(attr, DEVLINK_ATTR_RATE_TC_BWS, info->nlhdr,
+                                GENL_HDRLEN, rem) {
+               err = devlink_nl_rate_tc_bw_parse(attr, tc_bw, bitmap,
+                                                 info->extack);
+               if (err)
+                       return err;
+       }
+
+       for (i = 0; i < DEVLINK_RATE_TCS_MAX; i++) {
+               if (!test_bit(i, bitmap)) {
+                       NL_SET_ERR_MSG_FMT(info->extack,
+                                          "Bandwidth values must be specified for all %u traffic classes",
+                                          DEVLINK_RATE_TCS_MAX);
+                       return -EINVAL;
+               }
+       }
+
+       if (devlink_rate_is_leaf(devlink_rate))
+               err = ops->rate_leaf_tc_bw_set(devlink_rate, devlink_rate->priv,
+                                              tc_bw, info->extack);
+       else if (devlink_rate_is_node(devlink_rate))
+               err = ops->rate_node_tc_bw_set(devlink_rate, devlink_rate->priv,
+                                              tc_bw, info->extack);
+
+       if (err)
+               return err;
+
+       memcpy(devlink_rate->tc_bw, tc_bw, sizeof(tc_bw));
+
+       return 0;
+}
+
 static int devlink_nl_rate_set(struct devlink_rate *devlink_rate,
                               const struct devlink_ops *ops,
                               struct genl_info *info)
@@ -388,6 +495,12 @@ static int devlink_nl_rate_set(struct devlink_rate *devlink_rate,
                        return err;
        }
 
+       if (attrs[DEVLINK_ATTR_RATE_TC_BWS]) {
+               err = devlink_nl_rate_tc_bw_set(devlink_rate, info);
+               if (err)
+                       return err;
+       }
+
        return 0;
 }
 
@@ -423,6 +536,13 @@ static bool devlink_rate_set_ops_supported(const struct devlink_ops *ops,
                                            "TX weight set isn't supported for the leafs");
                        return false;
                }
+               if (attrs[DEVLINK_ATTR_RATE_TC_BWS] &&
+                   !ops->rate_leaf_tc_bw_set) {
+                       NL_SET_ERR_MSG_ATTR(info->extack,
+                                           attrs[DEVLINK_ATTR_RATE_TC_BWS],
+                                           "TC bandwidth set isn't supported for the leafs");
+                       return false;
+               }
        } else if (type == DEVLINK_RATE_TYPE_NODE) {
                if (attrs[DEVLINK_ATTR_RATE_TX_SHARE] && !ops->rate_node_tx_share_set) {
                        NL_SET_ERR_MSG(info->extack, "TX share set isn't supported for the nodes");
@@ -449,6 +569,13 @@ static bool devlink_rate_set_ops_supported(const struct devlink_ops *ops,
                                            "TX weight set isn't supported for the nodes");
                        return false;
                }
+               if (attrs[DEVLINK_ATTR_RATE_TC_BWS] &&
+                   !ops->rate_node_tc_bw_set) {
+                       NL_SET_ERR_MSG_ATTR(info->extack,
+                                           attrs[DEVLINK_ATTR_RATE_TC_BWS],
+                                           "TC bandwidth set isn't supported for the nodes");
+                       return false;
+               }
        } else {
                WARN(1, "Unknown type of rate object");
                return false;