Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures

From: Herbert Xu
Date: Thu Aug 16 2007 - 04:12:49 EST


On Thu, Aug 16, 2007 at 10:06:31AM +0200, Stefan Richter wrote:
> >
> > Do you (or anyone else for that matter) have an example of this?
>
> The only code I somewhat know, the ieee1394 subsystem, was perhaps
> authored and is currently maintained with the expectation that each
> occurrence of atomic_read actually results in a load operation, i.e. is
> not optimized away. This means all atomic_t (bus generation, packet and
> buffer refcounts, and some other state variables)* and likewise all
> atomic bitops in that subsystem.

Can you find an actual atomic_read code snippet there that is
broken without the volatile modifier?

Thanks,
--
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