Re: [PATCH V2 net 3/8] net/mlx5e: Preserve tc-bw during parent changes

ChaosEsque Team
2025-10-02T16:26:37Z

Mark Bloch.
Finally a normal name on this list.

(the rest is "Massive Dong Wang", and similar)

On Wed, Aug 20, 2025 at 10:03 AM Mark Bloch <mbloch@nvidia.com> wrote:
>
> From: Carolina Jubran <cjubran@nvidia.com>
>
> When changing parent of a node/leaf with tc-bw configured, the code
> saves and restores tc-bw values. However, it was reading the converted
> hardware bw_share values (where 0 becomes 1) instead of the original
> user values, causing incorrect tc-bw calculations after parent change.
>
> Store original tc-bw values in the node structure and use them directly
> for save/restore operations.
>
> Fixes: cf7e73770d1b ("net/mlx5: Manage TC arbiter nodes and implement full support for tc-bw")
> Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
> Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
> Signed-off-by: Mark Bloch <mbloch@nvidia.com>
> ---
> .../net/ethernet/mellanox/mlx5/core/esw/qos.c | 24 +++++++++----------
> 1 file changed, 12 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c b/drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c
> index cd58d3934596..4ed5968f1638 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c
> @@ -102,6 +102,8 @@ struct mlx5_esw_sched_node {
> u8 level;
> /* Valid only when this node represents a traffic class. */
> u8 tc;
> + /* Valid only for a TC arbiter node or vport TC arbiter. */
> + u32 tc_bw[DEVLINK_RATE_TCS_MAX];
> };
>
> static void esw_qos_node_attach_to_parent(struct mlx5_esw_sched_node *node)
> @@ -609,10 +611,7 @@ 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;
> + memcpy(tc_bw, tc_arbiter_node->tc_bw, sizeof(tc_arbiter_node->tc_bw));
> }
>
> static void
> @@ -629,6 +628,7 @@ esw_qos_set_tc_arbiter_bw_shares(struct mlx5_esw_sched_node *tc_arbiter_node,
> u8 tc = vports_tc_node->tc;
> u32 bw_share;
>
> + tc_arbiter_node->tc_bw[tc] = tc_bw[tc];
> bw_share = tc_bw[tc] * fw_max_bw_share;
> bw_share = esw_qos_calc_bw_share(bw_share, divider,
> fw_max_bw_share);
> @@ -1060,6 +1060,7 @@ static void esw_qos_vport_disable(struct mlx5_vport *vport, struct netlink_ext_a
> esw_qos_vport_tc_disable(vport, extack);
>
> vport_node->bw_share = 0;
> + memset(vport_node->tc_bw, 0, sizeof(vport_node->tc_bw));
> list_del_init(&vport_node->entry);
> esw_qos_normalize_min_rate(vport_node->esw, vport_node->parent, extack);
>
> @@ -1231,8 +1232,9 @@ static int esw_qos_vport_update(struct mlx5_vport *vport,
> struct mlx5_esw_sched_node *parent,
> struct netlink_ext_ack *extack)
> {
> - struct mlx5_esw_sched_node *curr_parent = vport->qos.sched_node->parent;
> - enum sched_node_type curr_type = vport->qos.sched_node->type;
> + struct mlx5_esw_sched_node *vport_node = vport->qos.sched_node;
> + struct mlx5_esw_sched_node *curr_parent = vport_node->parent;
> + enum sched_node_type curr_type = vport_node->type;
> u32 curr_tc_bw[DEVLINK_RATE_TCS_MAX] = {0};
> int err;
>
> @@ -1244,10 +1246,8 @@ static int esw_qos_vport_update(struct mlx5_vport *vport,
> 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);
> - }
> + if (curr_type == SCHED_NODE_TYPE_TC_ARBITER_TSAR && curr_type == type)
> + esw_qos_tc_arbiter_get_bw_shares(vport_node, curr_tc_bw);
>
> esw_qos_vport_disable(vport, extack);
>
> @@ -1258,8 +1258,8 @@ static int esw_qos_vport_update(struct mlx5_vport *vport,
> }
>
> 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);
> + esw_qos_set_tc_arbiter_bw_shares(vport_node, curr_tc_bw,
> + extack);
> }
>
> return err;
> --
> 2.34.1
>
>