[dpdk-dev] [PATCH 00/11] net/vhostpci: A new vhostpci PMD supporting VM2VM scenario

[Tan, Jianfeng]

Hi,

> -----Original Message-----
> From: Yang, Zhiyong
> Sent: Wednesday, December 20, 2017 9:52 AM
> To: Maxime Coquelin; dev at dpdk.org; yliu at fridaylinux.org
> Cc: Wang, Wei W; Tan, Jianfeng
> Subject: RE: [PATCH 00/11] net/vhostpci: A new vhostpci PMD supporting
> VM2VM scenario
> 
> Hi Maxime,
> 
> > -----Original Message-----
> > From: Maxime Coquelin [mailto:maxime.coquelin at redhat.com]
> > Sent: Tuesday, December 19, 2017 7:15 PM
> > To: Yang, Zhiyong <zhiyong.yang at intel.com>; dev at dpdk.org;
> > yliu at fridaylinux.org
> > Cc: Wang, Wei W <wei.w.wang at intel.com>; Tan, Jianfeng
> > <jianfeng.tan at intel.com>
> > Subject: Re: [PATCH 00/11] net/vhostpci: A new vhostpci PMD supporting
> > VM2VM scenario
> >
> 
> <snip>
> 
> > Thanks for the RFC.
> > It seems there is a lot of code duplication between this series and libvhost-
> user.
> >
> > Does the non-RFC would make reuse of libvhost-user? I'm thinking of all
> the
> > code copied from virtio-net.c for example.
> >
> > If not, I think this is problematic as it will double the maintenance cost.
> 
> Thank you for paying attention to the patchset . TX/RX logic basically comes
> from vhost user code.
> but some function interfaces and data structures are different,  So can not
> reuse them directly,
> code duplicate should be removed, I'm aware of this point too, when I was
> writing the vhostpci PMD.
>  But We should modify the  libvhost-user firstly,  let libvhostuser become
> more generic.
> It looks like that more and more PMDs are becoming the member of virtio
> family or are on the road.

Trying to draw a conclusion here, there are two kinds of code duplication in net/vhost-pci.
- For pci operations in guest driver, it has some duplicated code with virtio-net pmd.
- For the enqueue/dequeuer operations, it has some duplicated code with vhost-user lib.

Right?

Thanks,
Jianfeng

> 
> Thanks
> Zhiyong
> 
> >
> > Cheers,
> > Maxime