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

[Herbert Xu]

Chris Snook <csnook@xxxxxxxxxx> wrote:
> 
> Because atomic operations are generally used for synchronization, which requires 
> volatile behavior.  Most such codepaths currently use an inefficient barrier(). 
>  Some forget to and we get bugs, because people assume that atomic_read() 
> actually reads something, and atomic_write() actually writes something.  Worse, 
> these are architecture-specific, even compiler version-specific bugs that are 
> often difficult to track down.

I'm yet to see a single example from the current tree where
this patch series is the correct solution.  So far the only
example has been a buggy piece of code which has since been
fixed with a cpu_relax.

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