[RFC] net/vhost: support asynchronous data path

[Wang, YuanX]

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.
Maybe I should set the patch state to superseded?

Thanks,
Yuan

> -----Original Message-----
> From: Maxime Coquelin <maxime.coquelin at redhat.com>
> Sent: Monday, January 2, 2023 6:59 PM
> To: Wang, YuanX <yuanx.wang at intel.com>; dev at dpdk.org
> Cc: Hu, Jiayu <jiayu.hu at 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 at 0000:00.01.0;rxq0 at 0000:00.01.1],dma-
> ring-size=4096'
> >
> > Signed-off-by: Jiayu Hu <jiayu.hu at intel.com>
> > Signed-off-by: Yuan Wang <yuanx.wang at intel.com>
> > Signed-off-by: Wenwu Ma <wenwux.ma at 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