Messages in this thread | | | Date | Thu, 16 Aug 2007 13:20:26 -0700 (PDT) | From | Christoph Lameter <> | Subject | Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures |
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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. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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