Re: [PATCH] arp_queue: serializing unlink + kfree_skb

David S. Miller
2005-02-11T03:48:36Z

On Thu, 10 Feb 2005 15:56:47 +1100
Herbert Xu <herbert@gondor.apana.org.au> wrote:

> > ? If yes, is this a good idea ?
>
> Dave mentioned that on sparc64, atomic_inc_and_test is much more
> expensive than the second variant.

Actually, besides the memory barriers themselves, all variants
are equally expensive.

On old i386 chips, the test variants are indeed more expensive.
Linus told me this and there is a note about this in the
atomic_ops.txt file if you look at the current copy :-)