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

From: Herbert Xu
Date: Tue Aug 14 2007 - 03:27:49 EST


On Tue, Aug 14, 2007 at 03:34:25PM +1000, Nick Piggin wrote:
>
> What do you think of this crazy idea?
>
> /* Enforce a compiler barrier for only operations to location X.
> * Call multiple times to provide an ordering between multiple
> * memory locations. Other memory operations can be assumed by
> * the compiler to remain unchanged and may be reordered
> */
> #define order(x) asm volatile("" : "+m" (x))

Yes this is a very good idea. This also makes it explicit
that the coder is depending on this rather than the more
vague connotations of atomic_read.

Cheers,
--
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Email: Herbert Xu ~{PmV>HI~} <herbert@xxxxxxxxxxxxxxxxxxx>
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