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>
---
doc/guides/nics/mlx5.rst | 4 +++-
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(+), 1 deletion(-)
diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst
index b0614ae..f4632dc 100644
--- a/doc/guides/nics/mlx5.rst
+++ b/doc/guides/nics/mlx5.rst
@@ -302,8 +302,10 @@ Limitations
it with size limited to max LRO size, not to max RX packet length.
- LRO can be used with outer header of TCP packets of the standard format:
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 7c81ae1..224f72c 100644
--- a/drivers/common/mlx5/mlx5_devx_cmds.c
+++ b/drivers/common/mlx5/mlx5_devx_cmds.c
@@ -792,6 +792,8 @@ 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 1c84cea..1834132 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 487714f..5bf460a 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
