[PATCH net-next 05/15] net/mlx5: Manage TC arbiter nodes and implement full support for tc-bw

Tariq Toukan
2025-02-09T10:19:25Z

From: Carolina Jubran <cjubran@nvidia.com>

Introduce support for managing Traffic Class (TC) arbiter nodes and
associated vports TC nodes within the E-Switch QoS hierarchy. This
patch adds support for the new scheduling node type,
`SCHED_NODE_TYPE_VPORTS_TC_TSAR`, and implements full support for
setting tc-bw on both vports and nodes.

Key changes include:

- Introduced the new scheduling node type,
`SCHED_NODE_TYPE_VPORTS_TC_TSAR`, for managing vports within the TC
arbiter node.

- New helper functions for creating and destroying vports TC nodes
under the TC arbiter.

- Updated the minimum rate normalization function to skip nodes of type
`SCHED_NODE_TYPE_VPORTS_TC_TSAR`. Vports TC TSARs have bandwidth
shares configured on them but not minimum rates, so their `min_rate`
cannot be normalized.

- Implementation of `esw_qos_tc_arbiter_scheduling_setup()` and
`esw_qos_tc_arbiter_scheduling_teardown()` for initializing and
cleaning up TC arbiter scheduling elements. These functions now fully
support tc-bw configuration on TC arbiter nodes.

- Added `esw_qos_tc_arbiter_get_bw_shares()` and
`esw_qos_set_tc_arbiter_bw_shares()` to handle the settings of
bandwidth shares for vports traffic class TSARs.

- Refactored `mlx5_esw_devlink_rate_node_tc_bw_set()` and
`mlx5_esw_devlink_rate_leaf_tc_bw_set()` to fully support configuring
tc-bw on devlink rate nodes and vports, respectively.

Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
---
.../net/ethernet/mellanox/mlx5/core/esw/qos.c | 185 +++++++++++++++++-
1 file changed, 180 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c b/drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c
index 84f680aecfe2..097fda4d746b 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c
@@ -67,6 +67,7 @@ enum sched_node_type {
SCHED_NODE_TYPE_TC_ARBITER_TSAR,
SCHED_NODE_TYPE_RATE_LIMITER,
SCHED_NODE_TYPE_VPORT_TC,
+ SCHED_NODE_TYPE_VPORTS_TC_TSAR,
};

static const char * const sched_node_type_str[] = {
@@ -75,6 +76,7 @@ static const char * const sched_node_type_str[] = {
[SCHED_NODE_TYPE_TC_ARBITER_TSAR] = "TC Arbiter TSAR",
[SCHED_NODE_TYPE_RATE_LIMITER] = "Rate Limiter",
[SCHED_NODE_TYPE_VPORT_TC] = "vport TC",
+ [SCHED_NODE_TYPE_VPORTS_TC_TSAR] = "vports TC TSAR",
};

struct mlx5_esw_sched_node {
@@ -169,6 +171,11 @@ mlx5_esw_qos_vport_get_parent(const struct mlx5_vport *vport)
static void esw_qos_sched_elem_warn(struct mlx5_esw_sched_node *node, int err, const char *op)
{
switch (node->type) {
+ case SCHED_NODE_TYPE_VPORTS_TC_TSAR:
+ esw_warn(node->esw->dev,
+ "E-Switch %s %s scheduling element failed (tc=%d,err=%d)\n",
+ op, sched_node_type_str[node->type], node->tc, err);
+ break;
case SCHED_NODE_TYPE_VPORT_TC:
esw_warn(node->esw->dev,
"E-Switch %s %s scheduling element failed (vport=%d,tc=%d,err=%d)\n",
@@ -354,7 +361,11 @@ static void esw_qos_normalize_min_rate(struct mlx5_eswitch *esw,
if (node->esw != esw || node->ix == esw->qos.root_tsar_ix)
continue;

- esw_qos_update_sched_node_bw_share(node, divider, extack);
+ /* Vports TC TSARs don't have a minimum rate configured,
+ * so there's no need to update the bw_share on them.
+ */
+ if (node->type != SCHED_NODE_TYPE_VPORTS_TC_TSAR)
+ esw_qos_update_sched_node_bw_share(node, divider, extack);

if (list_empty(&node->children))
continue;
@@ -488,6 +499,129 @@ static void esw_qos_destroy_node(struct mlx5_esw_sched_node *node, struct netlin
__esw_qos_free_node(node);
}

+static int esw_qos_create_vports_tc_node(struct mlx5_esw_sched_node *parent, u8 tc,
+ struct netlink_ext_ack *extack)
+{
+ u32 tsar_ctx[MLX5_ST_SZ_DW(scheduling_context)] = {};
+ struct mlx5_core_dev *dev = parent->esw->dev;
+ struct mlx5_esw_sched_node *vports_tc_node;
+ void *attr;
+ int err;
+
+ if (!mlx5_qos_element_type_supported(dev,
+ SCHEDULING_CONTEXT_ELEMENT_TYPE_TSAR,
+ SCHEDULING_HIERARCHY_E_SWITCH) ||
+ !mlx5_qos_tsar_type_supported(dev,
+ TSAR_ELEMENT_TSAR_TYPE_DWRR,
+ SCHEDULING_HIERARCHY_E_SWITCH))
+ return -EOPNOTSUPP;
+
+ vports_tc_node = __esw_qos_alloc_node(parent->esw, 0, SCHED_NODE_TYPE_VPORTS_TC_TSAR,
+ parent);
+ if (!vports_tc_node) {
+ NL_SET_ERR_MSG_MOD(extack, "E-Switch alloc node failed");
+ esw_warn(dev, "Failed to alloc vports TC node (tc=%d)\n", tc);
+ return -ENOMEM;
+ }
+
+ attr = MLX5_ADDR_OF(scheduling_context, tsar_ctx, element_attributes);
+ MLX5_SET(tsar_element, attr, tsar_type, TSAR_ELEMENT_TSAR_TYPE_DWRR);
+ MLX5_SET(tsar_element, attr, traffic_class, tc);
+ MLX5_SET(scheduling_context, tsar_ctx, parent_element_id, parent->ix);
+ MLX5_SET(scheduling_context, tsar_ctx, element_type, SCHEDULING_CONTEXT_ELEMENT_TYPE_TSAR);
+
+ err = esw_qos_node_create_sched_element(vports_tc_node, tsar_ctx, extack);
+ if (err)
+ goto err_create_sched_element;
+
+ vports_tc_node->tc = tc;
+
+ return 0;
+
+err_create_sched_element:
+ __esw_qos_free_node(vports_tc_node);
+ return err;
+}
+
+static void
+esw_qos_tc_arbiter_get_bw_shares(struct mlx5_esw_sched_node *tc_arbiter_node, u32 *tc_bw)
+{
+ struct mlx5_esw_sched_node *vports_tc_node;
+
+ list_for_each_entry(vports_tc_node, &tc_arbiter_node->children, entry)
+ tc_bw[vports_tc_node->tc] = vports_tc_node->bw_share;
+}
+
+static void esw_qos_set_tc_arbiter_bw_shares(struct mlx5_esw_sched_node *tc_arbiter_node,
+ u32 *tc_bw, struct netlink_ext_ack *extack)
+{
+ struct mlx5_esw_sched_node *vports_tc_node;
+
+ list_for_each_entry(vports_tc_node, &tc_arbiter_node->children, entry) {
+ u32 bw_share;
+ u8 tc;
+
+ tc = vports_tc_node->tc;
+ bw_share = tc_bw[tc] ?: MLX5_MIN_BW_SHARE;
+ esw_qos_sched_elem_config(vports_tc_node, 0, bw_share, extack);
+ }
+}
+
+static void esw_qos_destroy_vports_tc_nodes(struct mlx5_esw_sched_node *tc_arbiter_node,
+ struct netlink_ext_ack *extack)
+{
+ struct mlx5_esw_sched_node *vports_tc_node, *tmp;
+
+ list_for_each_entry_safe(vports_tc_node, tmp, &tc_arbiter_node->children, entry)
+ esw_qos_destroy_node(vports_tc_node, extack);
+}
+
+static int esw_qos_create_vports_tc_nodes(struct mlx5_esw_sched_node *tc_arbiter_node,
+ struct netlink_ext_ack *extack)
+{
+ struct mlx5_eswitch *esw = tc_arbiter_node->esw;
+ int err, i, num_tcs = esw_qos_num_tcs(esw->dev);
+
+ for (i = 0; i < num_tcs; i++) {
+ err = esw_qos_create_vports_tc_node(tc_arbiter_node, i, extack);
+ if (err)
+ goto err_tc_node_create;
+ }
+
+ return 0;
+
+err_tc_node_create:
+ esw_qos_destroy_vports_tc_nodes(tc_arbiter_node, NULL);
+ return err;
+}
+
+static int esw_qos_create_tc_arbiter_sched_elem(struct mlx5_esw_sched_node *tc_arbiter_node,
+ struct netlink_ext_ack *extack)
+{
+ u32 tsar_ctx[MLX5_ST_SZ_DW(scheduling_context)] = {};
+ u32 tsar_parent_ix;
+ void *attr;
+
+ if (!mlx5_qos_tsar_type_supported(tc_arbiter_node->esw->dev,
+ TSAR_ELEMENT_TSAR_TYPE_TC_ARB,
+ SCHEDULING_HIERARCHY_E_SWITCH)) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "E-Switch TC Arbiter scheduling element is not supported");
+ return -EOPNOTSUPP;
+ }
+
+ attr = MLX5_ADDR_OF(scheduling_context, tsar_ctx, element_attributes);
+ MLX5_SET(tsar_element, attr, tsar_type, TSAR_ELEMENT_TSAR_TYPE_TC_ARB);
+ tsar_parent_ix = tc_arbiter_node->parent ? tc_arbiter_node->parent->ix :
+ tc_arbiter_node->esw->qos.root_tsar_ix;
+ MLX5_SET(scheduling_context, tsar_ctx, parent_element_id, tsar_parent_ix);
+ MLX5_SET(scheduling_context, tsar_ctx, element_type, SCHEDULING_CONTEXT_ELEMENT_TYPE_TSAR);
+ MLX5_SET(scheduling_context, tsar_ctx, max_average_bw, tc_arbiter_node->max_rate);
+ MLX5_SET(scheduling_context, tsar_ctx, bw_share, tc_arbiter_node->bw_share);
+
+ return esw_qos_node_create_sched_element(tc_arbiter_node, tsar_ctx, extack);
+}
+
static struct mlx5_esw_sched_node *
__esw_qos_create_vports_sched_node(struct mlx5_eswitch *esw, struct mlx5_esw_sched_node *parent,
struct netlink_ext_ack *extack)
@@ -551,6 +685,9 @@ static void __esw_qos_destroy_node(struct mlx5_esw_sched_node *node, struct netl
{
struct mlx5_eswitch *esw = node->esw;

+ if (node->type == SCHED_NODE_TYPE_TC_ARBITER_TSAR)
+ esw_qos_destroy_vports_tc_nodes(node, extack);
+
trace_mlx5_esw_node_qos_destroy(esw->dev, node, node->ix);
esw_qos_destroy_node(node, extack);
esw_qos_normalize_min_rate(esw, NULL, extack);
@@ -640,13 +777,38 @@ static void esw_qos_put(struct mlx5_eswitch *esw)

static void esw_qos_tc_arbiter_scheduling_teardown(struct mlx5_esw_sched_node *node,
struct netlink_ext_ack *extack)
-{}
+{
+ /* Clean up all Vports TC nodes within the TC arbiter node. */
+ esw_qos_destroy_vports_tc_nodes(node, extack);
+ /* Destroy the scheduling element for the TC arbiter node itself. */
+ esw_qos_node_destroy_sched_element(node, extack);
+}

static int esw_qos_tc_arbiter_scheduling_setup(struct mlx5_esw_sched_node *node,
struct netlink_ext_ack *extack)
{
- NL_SET_ERR_MSG_MOD(extack, "TC arbiter elements are not supported.");
- return -EOPNOTSUPP;
+ u32 curr_ix = node->ix;
+ int err;
+
+ err = esw_qos_create_tc_arbiter_sched_elem(node, extack);
+ if (err)
+ return err;
+ /* Initialize the vports TC nodes within created TC arbiter TSAR. */
+ err = esw_qos_create_vports_tc_nodes(node, extack);
+ if (err)
+ goto err_vports_tc_nodes;
+
+ node->type = SCHED_NODE_TYPE_TC_ARBITER_TSAR;
+
+ return 0;
+
+err_vports_tc_nodes:
+ /* If initialization fails, clean up the scheduling element
+ * for the TC arbiter node.
+ */
+ esw_qos_node_destroy_sched_element(node, NULL);
+ node->ix = curr_ix;
+ return err;
}

static int esw_qos_create_vport_tc_sched_node(struct mlx5_vport *vport,
@@ -977,6 +1139,7 @@ static int esw_qos_vport_update(struct mlx5_vport *vport, enum sched_node_type t
{
struct mlx5_esw_sched_node *curr_parent = vport->qos.sched_node->parent;
enum sched_node_type curr_type = vport->qos.sched_node->type;
+ u32 curr_tc_bw[IEEE_8021QAZ_MAX_TCS] = {0};
int err;

esw_assert_qos_lock_held(vport->dev->priv.eswitch);
@@ -988,11 +1151,19 @@ static int esw_qos_vport_update(struct mlx5_vport *vport, enum sched_node_type t
if (err)
return err;

+ if (curr_type == SCHED_NODE_TYPE_TC_ARBITER_TSAR && curr_type == type)
+ esw_qos_tc_arbiter_get_bw_shares(vport->qos.sched_node, curr_tc_bw);
+
esw_qos_vport_disable(vport, extack);

err = esw_qos_vport_enable(vport, type, parent, extack);
- if (err)
+ if (err) {
esw_qos_vport_enable(vport, curr_type, curr_parent, NULL);
+ extack = NULL;
+ }
+
+ if (curr_type == SCHED_NODE_TYPE_TC_ARBITER_TSAR && curr_type == type)
+ esw_qos_set_tc_arbiter_bw_shares(vport->qos.sched_node, curr_tc_bw, extack);

return err;
}
@@ -1429,6 +1600,8 @@ int mlx5_esw_devlink_rate_leaf_tc_bw_set(struct devlink_rate *rate_leaf, void *p
} else {
err = esw_qos_vport_update(vport, SCHED_NODE_TYPE_TC_ARBITER_TSAR, NULL, extack);
}
+ if (!err)
+ esw_qos_set_tc_arbiter_bw_shares(vport_node, tc_bw, extack);
unlock:
esw_qos_unlock(esw);
return err;
@@ -1455,6 +1628,8 @@ int mlx5_esw_devlink_rate_node_tc_bw_set(struct devlink_rate *rate_node, void *p
}

err = esw_qos_node_enable_tc_arbitration(node, extack);
+ if (!err)
+ esw_qos_set_tc_arbiter_bw_shares(node, tc_bw, extack);
unlock:
esw_qos_unlock(esw);
return err;
--
2.45.0