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

From: Christoph Lameter <clameter@xxxxxxx>
Date: Thu, 16 Aug 2007 13:20:26 -0700 (PDT)

On Thu, 16 Aug 2007, Chris Snook wrote:

atomic_dec() already has volatile behavior everywhere, so this is semantically
okay, but this code (and any like it) should be calling cpu_relax() each
iteration through the loop, unless there's a compelling reason not to. I'll
allow that for some hardware drivers (possibly this one) such a compelling
reason may exist, but hardware-independent core subsystems probably have no
excuse.

No it does not have any volatile semantics. atomic_dec() can be reordered
at will by the compiler within the current basic unit if you do not add a
barrier.
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Follow-Ups:
- Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures
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- Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures
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References:
- Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures
  - From: Paul E. McKenney
- Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures
  - From: Christoph Lameter
- Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures
  - From: Paul Mackerras
- Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures
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  - From: Paul Mackerras
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  - From: Satyam Sharma
- Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures
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- Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures
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