On Thu, Aug 16, 2007 at 01:20:26PM -0700, Christoph Lameter wrote:
> On Thu, 16 Aug 2007, Chris Snook wrote:
>
> > atomic_dec() already has volatile behavior everywhere, so this is
> > semantically
> > okay, but this code (and any like it) should be calling cpu_relax() each
> > iteration through the loop, unless there's a compelling reason not to. I'll
> > allow that for some hardware drivers (possibly this one) such a compelling
> > reason may exist, but hardware-independent core subsystems probably have no
> > excuse.
>
> No it does not have any volatile semantics. atomic_dec() can be reordered
> at will by the compiler within the current basic unit if you do not add a
> barrier.
Yep. Or you can use atomic_dec_return() instead of using a barrier.
Thanx, Paul
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