Subject: Re: [net-next, RFC, 4/8] net: core: add recycle capabilities on skbs via page_pool API

From: Florian Westphal <[email-masked]>
Date: Sat, 8 Dec 2018 10:57:58 +0100

Jesper Dangaard Brouer <[email-masked]> wrote:
> From: Ilias Apalodimas <[email-masked]>
> 
> This patch is changing struct sk_buff, and is thus per-definition
> controversial.
> 
> Place a new member 'mem_info' of type struct xdp_mem_info, just after
> members (flags) head_frag and pfmemalloc, And not in between
> headers_start/end to ensure skb_copy() and pskb_copy() work as-is.
> Copying mem_info during skb_clone() is required.  This makes sure that
> pages are correctly freed or recycled during the altered
> skb_free_head() invocation.

I read this to mean that this 'info' isn't accessed/needed until skb
is freed.  Any reason its not added at the end?

This would avoid moving other fields that are probably accessed
more frequently during processing.