Add debug printout showing HCA capability lro_min_mss_size - the minimal size of TCP segment required for coalescing. MLX5 PMD documentation is updated to note this condition.
Signed-off-by: Dekel Peled <dek...@nvidia.com> Acked-by: Matan Azrad <ma...@nvidia.com> --- doc/guides/nics/mlx5.rst | 3 +++ drivers/common/mlx5/mlx5_devx_cmds.c | 2 ++ drivers/common/mlx5/mlx5_devx_cmds.h | 1 + drivers/net/mlx5/linux/mlx5_os.c | 3 +++ 4 files changed, 9 insertions(+) diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst index a071db2..f3afb24 100644 --- a/doc/guides/nics/mlx5.rst +++ b/doc/guides/nics/mlx5.rst @@ -304,6 +304,9 @@ Limitations eth (with or without vlan) / ipv4 or ipv6 / tcp / payload Other TCP packets (e.g. with MPLS label) received on Rx queue with LRO enabled, will be received with bad checksum. + - LRO packet aggregation is performed by HW only for packet size larger than + ``lro_min_mss_size``. This value is reported on device start, when debug + mode is enabled. - CRC: diff --git a/drivers/common/mlx5/mlx5_devx_cmds.c b/drivers/common/mlx5/mlx5_devx_cmds.c index fd4e3f2..d3e90b5 100644 --- a/drivers/common/mlx5/mlx5_devx_cmds.c +++ b/drivers/common/mlx5/mlx5_devx_cmds.c @@ -819,6 +819,8 @@ struct mlx5_devx_obj * MLX5_GET(per_protocol_networking_offload_caps, hcattr, lro_timer_supported_periods[i]); } + attr->lro_min_mss_size = MLX5_GET(per_protocol_networking_offload_caps, + hcattr, lro_min_mss_size); attr->tunnel_stateless_geneve_rx = MLX5_GET(per_protocol_networking_offload_caps, hcattr, tunnel_stateless_geneve_rx); diff --git a/drivers/common/mlx5/mlx5_devx_cmds.h b/drivers/common/mlx5/mlx5_devx_cmds.h index cfa7a7b..c2d089c 100644 --- a/drivers/common/mlx5/mlx5_devx_cmds.h +++ b/drivers/common/mlx5/mlx5_devx_cmds.h @@ -85,6 +85,7 @@ struct mlx5_hca_attr { uint32_t tunnel_lro_vxlan:1; uint32_t lro_max_msg_sz_mode:2; uint32_t lro_timer_supported_periods[MLX5_LRO_NUM_SUPP_PERIODS]; + uint16_t lro_min_mss_size; uint32_t flex_parser_protocols; uint32_t hairpin:1; uint32_t log_max_hairpin_queues:5; diff --git a/drivers/net/mlx5/linux/mlx5_os.c b/drivers/net/mlx5/linux/mlx5_os.c index 09d0944..e0a5a21 100644 --- a/drivers/net/mlx5/linux/mlx5_os.c +++ b/drivers/net/mlx5/linux/mlx5_os.c @@ -1071,6 +1071,9 @@ config->hca_attr.lro_timer_supported_periods[0]; DRV_LOG(DEBUG, "LRO session timeout set to %d usec", config->lro.timeout); + DRV_LOG(DEBUG, "LRO minimal size of TCP segment " + "required for coalescing is %d bytes", + config->hca_attr.lro_min_mss_size); } #if defined(HAVE_MLX5DV_DR) && defined(HAVE_MLX5_DR_CREATE_ACTION_FLOW_METER) if (config->hca_attr.qos.sup && -- 1.8.3.1