ConnectX-4LX supports multiple packets within the single Tx
descriptor. This feature is named as "Legacy Multi-Packet Write"
and imposes a lot of limitations:
- no ACLs, it means no NIC Tx Flows are supported and Tx metadata
become meaningless
- the required minimal inline data must be zero
- no SR-IOV, it means no support in E-Switch configurations,
- no priority and dscp forcing
- no VLAN insertion
- no TSO
- all packets within MPW session must have the same size
This legacy MPW feature is mainly intended for test purposes.
To explicitly engage the feature on ConnectX-4LX the devargs
should be specified:
- txq_mpw_en=1
This feature was dropped in 19.08, this patch reverts it back.
Fixes: 18a1c20044c0 ("net/mlx5: implement Tx burst template")
Cc: stable@dpdk.org
Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
Acked-by: Matan Azrad <matan@mellanox.com>
82e75f8323