Re: [RFC] net/vhost: support asynchronous data path

[Maxime Coquelin]

Hi,

On 1/6/23 10:08, Wang, YuanX wrote:

Hi Maxime,

Sorry about not being clear about the intentions.
The patch is for a whitepaper, we use it for tests and we need to attach the 
patch link.

Thanks for the clarification.

Maybe I should set the patch state to superseded?

I think setting it to rejected would be the appropriate state, as there
are no patch that supersedes it.

Thanks,
Maxime

Thanks,
Yuan

-----Original Message-----
From: Maxime Coquelin <maxime.coque...@redhat.com>
Sent: Monday, January 2, 2023 6:59 PM
To: Wang, YuanX <yuanx.w...@intel.com>; dev@dpdk.org
Cc: Hu, Jiayu <jiayu...@intel.com>
Subject: Re: [RFC] net/vhost: support asynchronous data path

Hi Yuan,

On 12/16/22 03:00, Yuan Wang wrote:

Vhost asynchronous data-path offloads packet copy from the CPU to the
DMA engine. As a result, large packet copy can be accelerated by the
DMA engine, and vhost can free CPU cycles for higher level functions.

In this patch, we enable asynchronous data-path for vhostpmd.
Asynchronous data path is enabled per tx/rx queue, and users need to
specify the DMA device used by the tx/rx queue. Each tx/rx queue only
supports to use one DMA device, but one DMA device can be shared

among

multiple tx/rx queues of different vhost PMD ports.

Two PMD parameters are added:
- dmas: specify the used DMA device for a tx/rx queue.
        (Default: no queues enable asynchronous data path)
- dma-ring-size: DMA ring size.
        (Default: 4096).

Here is an example:
--vdev

'eth_vhost0,iface=./s0,dmas=[txq0@0000:00.01.0;rxq0@0000:00.01.1],dma-
ring-size=4096'

Signed-off-by: Jiayu Hu <jiayu...@intel.com>
Signed-off-by: Yuan Wang <yuanx.w...@intel.com>
Signed-off-by: Wenwu Ma <wenwux...@intel.com>
---
   drivers/net/vhost/meson.build     |   1 +
   drivers/net/vhost/rte_eth_vhost.c | 512

++++++++++++++++++++++++++++--

   drivers/net/vhost/rte_eth_vhost.h |  15 +
   drivers/net/vhost/version.map     |   7 +
   drivers/net/vhost/vhost_testpmd.c |  67 ++++
   5 files changed, 569 insertions(+), 33 deletions(-)
   create mode 100644 drivers/net/vhost/vhost_testpmd.c

This RFC is identical to the v5 that you sent for last release, and so the
comments I made on it are still valid.

Is this intentionally re-sent?

Regards,
Maxime