Subject: Re: [PATCH net-next 3/8] cadence: macb: Add page pool support handle multi-descriptor frame rx

From: Paolo Valerio <[email-masked]>
Date: Thu, 22 Jan 2026 23:24:05 +0100

On 16 Jan 2026 at 06:16:16 PM, Andrew Lunn <[email-masked]> wrote:

> On Thu, Jan 15, 2026 at 11:25:26PM +0100, Paolo Valerio wrote:
>> Use the page pool allocator for the data buffers and enable skb recycling
>> support, instead of relying on netdev_alloc_skb allocating the entire skb
>> during the refill.
>
> Do you have any benchmark numbers for this change? Often swapping to
> page pool improves the performance of the driver, and i use it as a
> selling point for doing the conversion, independent of XDP.
>

I finally got the chance to get my hands on the board.

On the rpi5 I simply run xdp-bench in skb-mode to drop and collect the
stats.

Page size is 4k and stats include the driver consuming a full page
setting mtu such that rx_buffer_size + overhead exceed half page and the
other way around for 2 fragments.

             |    64     |    128    |
  baseline   |  533,158  |  531,618  |
  pp page    |  530,929  |  529,682  |
  pp 2 frags |  530,781  |  529,116  |

> Thanks
> 	Andrew