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Date: Mon, 20 Aug 2007 09:15:11 -0400
From: Chris Snook <csnook@redhat.com>
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Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all
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To: Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds wrote:
> So the only reason to add back "volatile" to the atomic_read() sequence is 
> not to fix bugs, but to _hide_ the bugs better. They're still there, they 
> are just a lot harder to trigger, and tend to be a lot subtler.

What about barrier removal?  With consistent semantics we could optimize a fair 
amount of code.  Whether or not that constitutes "premature" optimization is 
open to debate, but there's no question we could reduce our register wiping in 
some places.

	-- Chris