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

From: Denys Vlasenko
Date: Fri Aug 24 2007 - 08:52:28 EST


On Thursday 16 August 2007 00:22, Paul Mackerras wrote:
> Satyam Sharma writes:
> In the kernel we use atomic variables in precisely those situations
> where a variable is potentially accessed concurrently by multiple
> CPUs, and where each CPU needs to see updates done by other CPUs in a
> timely fashion. That is what they are for. Therefore the compiler
> must not cache values of atomic variables in registers; each
> atomic_read must result in a load and each atomic_set must result in a
> store. Anything else will just lead to subtle bugs.

Amen.
--
vda
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