[PATCH net-next] net/mlx5e: Add hds-thresh query support via ethtool

From: Tariq Toukan

Date: Tue Mar 17 2026 - 06:54:58 EST


From: Nimrod Oren <noren@xxxxxxxxxx>

Add support for reporting HDS (Header-Data Split) threshold via
ethtool. When applicable, mlx5 hardware splits packets of all sizes with
no configurable threshold, so report both hds-thresh and hds-thresh-max
as 0 (i.e. always split regardless of size).

Signed-off-by: Nimrod Oren <noren@xxxxxxxxxx>
Reviewed-by: Carolina Jubran <cjubran@xxxxxxxxxx>
Reviewed-by: Dragos Tatulea <dtatulea@xxxxxxxxxx>
Signed-off-by: Tariq Toukan <tariqt@xxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
index 4a8dc85d5924..bb61e2179078 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
@@ -371,6 +371,9 @@ void mlx5e_ethtool_get_ringparam(struct mlx5e_priv *priv,
param->tx_max_pending = 1 << MLX5E_PARAMS_MAXIMUM_LOG_SQ_SIZE;
param->rx_pending = 1 << priv->channels.params.log_rq_mtu_frames;
param->tx_pending = 1 << priv->channels.params.log_sq_size;
+
+ kernel_param->hds_thresh = 0;
+ kernel_param->hds_thresh_max = 0;
}

static void mlx5e_get_ringparam(struct net_device *dev,
@@ -2735,7 +2738,8 @@ const struct ethtool_ops mlx5e_ethtool_ops = {
ETHTOOL_COALESCE_USE_ADAPTIVE |
ETHTOOL_COALESCE_USE_CQE,
.supported_input_xfrm = RXH_XFRM_SYM_OR_XOR,
- .supported_ring_params = ETHTOOL_RING_USE_TCP_DATA_SPLIT,
+ .supported_ring_params = ETHTOOL_RING_USE_TCP_DATA_SPLIT |
+ ETHTOOL_RING_USE_HDS_THRS,
.get_drvinfo = mlx5e_get_drvinfo,
.get_link = ethtool_op_get_link,
.get_link_ext_state = mlx5e_get_link_ext_state,

base-commit: 348baefbb635cbb448e154f38c93657d4cf23936
--
2.44.0