Re: [dpdk-dev] [PATCH 0/5] new mlx4 Tx datapath bypassing ibverbs

["Nélio Laranjeiro" <nelio.laranjeiro@6wind.com>]

Hi Moti,

Small comments/question to clarify the situation for any user of this
series.

On Thu, Aug 24, 2017 at 06:54:05PM +0300, Moti Haimovsky wrote:
> This series of patches implements the mlx4-pmd with Tx data path that directly
> access the device queues for transmitting packets, bypassing the ibverbs Tx
> data path altogether.
> Using this scheme allows the PMD to work with upstream rdma-core package
> instead of the Mellanox OFED one without sacrificing Tx functionality.
> 
> These patches should be applied in the order listed below as each depends on
> its predecessor to work.
> 
> This implementation allows rapid deployment of new features without the need to
> update the underlying OFED.

Seems this explanation is wrong, the PMD still relies on Verbs for
control plane configuration and thus for new features it will still
require an update of the underlying layers i.e RDMA-Core or MLNX_OFED >=
4.2 and the associated Linux Kernel Mellanox drivers.

> This work depends on
>         http://dpdk.org/ml/archives/dev/2017-August/072281.html
>         [dpdk-dev] [PATCH v1 00/48] net/mlx4: trim and refactor entire PMD
> by Adrien Mazarguil
> 
> It had been built and tested using rdma-core-15-1 from
>  https://github.com/linux-rdma/rdma-core
> and kernel-ml-4.12.0-1.el7.elrepo.x86_64
> 
> It had been built and tested using rdma-core-15-1 from
>  https://github.com/linux-rdma/rdma-core

Seems this version (15-1) does not exists on this repository the latest
being v15.
Does this series compiles and work on this version, or should the user
use some point above the v15?

> and kernel-ml-4.12.0-1.el7.elrepo.x86_64
> 
> Moti Haimovsky (5):
>   net/mlx4: add simple Tx bypassing ibverbs
>   net/mlx4: support multi-segments Tx
>   net/mlx4: refine setting Tx completion flag
>   net/mlx4: add Tx checksum offloads
>   net/mlx4: add loopback Tx from VF
> 
>  drivers/net/mlx4/mlx4.c        |   7 +
>  drivers/net/mlx4/mlx4.h        |   2 +
>  drivers/net/mlx4/mlx4_ethdev.c |   6 +
>  drivers/net/mlx4/mlx4_prm.h    | 249 ++++++++++++++++++++++
>  drivers/net/mlx4/mlx4_rxtx.c   | 456 +++++++++++++++++++++++++++++++++--------
>  drivers/net/mlx4/mlx4_rxtx.h   |  39 +++-
>  drivers/net/mlx4/mlx4_txq.c    |  66 +++++-
>  mk/rte.app.mk                  |   2 +-
>  8 files changed, 734 insertions(+), 93 deletions(-)
>  create mode 100644 drivers/net/mlx4/mlx4_prm.h
> 
> -- 
> 1.8.3.1

Thanks,

-- 
Nélio Laranjeiro
6WIND