Re: [PATCH 1/3] skb: Drop bad code from pskb_expand_head

From: Eric Dumazet <redacted>
Date: Sat, 05 May 2012 07:35:30 +0200

On Fri, 2012-05-04 at 17:26 -0700, Alexander Duyck wrote:

quoted

The fast-path for pskb_expand_head contains a check where the size plus the
unaligned size of skb_shared_info is compared against the size of the data
buffer.  This code path has two issues.  First is the fact that after the
recent changes by Eric Dumazet to __alloc_skb and build_skb the shared info
is always placed in the optimal spot for a buffer size making this check
unnecessary.  The second issue is the fact that the check doesn't take into
account the aligned size of shared info.  As a result the code burns cycles
doing a memcpy with nothing actually being shifted.

Signed-off-by: Alexander Duyck <redacted>

 ...

Acked-by: Eric Dumazet <edumazet@google.com>

Applied.