From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Lameter <clameter@sgi.com>
Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all
 architectures
Date: Tue, 14 Aug 2007 16:14:21 -0700 (PDT)
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Cc: Satyam Sharma <satyam@infradead.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	linux-arch@vger.kernel.org, torvalds@linux-foundation.org,
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To: Chris Snook <csnook@redhat.com>
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On Tue, 14 Aug 2007, Chris Snook 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.

Looks like we need to have lock and unlock semantics?

atomic_read()

which has no barrier or volatile implications.

atomic_read_for_lock

	Acquire semantics?


atomic_read_for_unlock

	Release semantics?