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

From: Herbert Xu
Date: Wed Aug 15 2007 - 02:51:03 EST


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,
--
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@xxxxxxxxxxxxxxxxxxx>
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