Re: [PATCH 6/24] make atomic_read() behave consistently on frv

[Chris Snook]

David Howells wrote:
> Chris Snook <csnook@xxxxxxxxxx> wrote:
>
> > To head off the criticism, I admit this is an oversimplification, and true
> > busy-waiters should be using cpu_relax(), which contains a barrier.
>
> Why would you want to use cpu_relax()?  That's there to waste time efficiently,
> isn't it?  Shouldn't you be using smp_rmb() or something like that?
>
> David

cpu_relax() contains a barrier, so it should do the right thing.  For 
non-smp architectures, I'm concerned about interacting with interrupt 
handlers.  Some drivers do use atomic_* operations.

	-- Chris
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