Re: [PATCH 04/10] net: pad skb data and shinfo as a whole rather than individually

Eric Dumazet
2012-04-10T15:01:40Z

On Tue, 2012-04-10 at 15:26 +0100, Ian Campbell wrote:
> This reduces the minimum overhead required for this allocation such that the
> shinfo can be grown in the following patch without overflowing 2048 bytes for a
> 1500 byte frame.
>
> Reducing this overhead while also growing the shinfo means that sometimes the
> tail end of the data can end up in the same cache line as the beginning of the
> shinfo. Specifically in the case of the 64 byte cache lines on a 64 bit system
> the first 8 bytes of shinfo can overlap the tail cacheline of the data. In many
> cases the allocation slop means that there is no overlap.
>
> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Eric Dumazet <eric.dumazet@gmail.com>
> ---

Acked-by: Eric Dumazet <eric.dumazet@gmail.com>