[PATCH] examples/multi_process: add options to control port configuration

[Ma, WenwuX]

> -----Original Message-----
> From: Richardson, Bruce <bruce.richardson at intel.com>
> Sent: 2022年2月17日 17:06
> To: Ma, WenwuX <wenwux.ma at intel.com>
> Cc: Burakov, Anatoly <anatoly.burakov at intel.com>; dev at dpdk.org; Hu,
> Jiayu <jiayu.hu at intel.com>; Wang, Yinan <yinan.wang at intel.com>; He,
> Xingguang <xingguang.he at intel.com>
> Subject: Re: [PATCH] examples/multi_process: add options to control port
> configuration
> 
> On Thu, Feb 17, 2022 at 03:17:55PM +0000, Wenwu Ma wrote:
> > The default values of rx mq_mode and rx offloads for port will cause
> > symmetric_mp startup failure if the port do not support rss or csum.
> > Therefore, we added two new options --rx-mq-mode and --rx-offloads,
> > through which the user can set the values appropriately according to
> > the situation to make app startup normally.
> >
> > Signed-off-by: Wenwu Ma <wenwux.ma at intel.com> ---
> 
> The idea seems reasonable enough, but I think the implementation requiring
> the user to pass in special "magic numbers" for the offload values is not a
> good idea. Perhaps add in a separate flag for "no-csum" to disable that.
> 
> For the no-rss case, can you explain how you would see this app being used
> in the absense of RSS support to distribute traffic among the separate
> processes?

When app run in qemu vm and the backend is dpdk vhost, it will report error below:
"virtio_dev_configure(): RSS support requested but not supported by the device"