[PATCH] synchronize_irq needs a barrier

[Herbert Xu]

Benjamin Herrenschmidt <benh at kernel.crashing.org> wrote:
> 
> Note that some kind of read barrier or compiler barrier should be needed
> regardless, or we are just not sync'ing with anything at all (we may
> have loaded the value ages ago and thus operate on a totally stale
> value). I prefer a full barrier to also ensure all previous stores are
> pushed out.

We already have a compiler barrier there in the form of cpu_relax.

Cheers,
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert at gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt