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SubjectRe: [PATCH v2 16/18] x86: io: implement dummy relaxed accessor macros for writes
On 05/22/2014 09:47 AM, Will Deacon wrote:
> write{b,w,l,q}_relaxed are implemented by some architectures in order to
> permit memory-mapped I/O accesses with weaker barrier semantics than the
> non-relaxed variants.
>
> This patch adds dummy macros for the read and write accessors to x86,
> which simply expand to the non-relaxed variants. Note that this
> strengthens the relaxed read accessors, since they are now ordered with
> respect to each other by way of a compiler barrier.

OK, do we want/need that compiler barrier? And you say "strengthens" -
strengthens with respect to what if we didn't have them before?

-hpa



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