Subject: Re: [PATCH net-next v2 12/33] hv_netvsc: add XDP frame size to driver

From: Jesper Dangaard Brouer <[email-masked]>
Date: Fri, 1 May 2020 16:47:03 +0200

On Thu, 30 Apr 2020 14:20:20 +0000
Haiyang Zhang <[email-masked]> wrote:
> > -----Original Message-----
> > From: Jesper Dangaard Brouer <[email-masked]>
> > 
> > The hyperv NIC drivers XDP implementation is rather disappointing as it will
> > be a slowdown to enable XDP on this driver, given it will allocate a new page
> > for each packet and copy over the payload, before invoking the XDP BPF-
> > prog.  
>
> This needs correction. As I said previously -- 
> This statement is not accurate -- The data path of netvsc driver does memory 
> allocation and copy even without XDP, so it's not "a slowdown to enable XDP".

Okay, I have changed the paragraph text to:

 The hyperv NIC driver does memory allocation and copy even without XDP.
 In XDP mode it will allocate a new page for each packet and copy over
 the payload, before invoking the XDP BPF-prog.

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer