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: Thu, 16 Aug 2007 11:48:23 -0700 (PDT)
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Cc: Herbert Xu <herbert@gondor.apana.org.au>,
	Satyam Sharma <satyam@infradead.org>,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
	Stefan Richter <stefanr@s5r6.in-berlin.de>,
	Chris Snook <csnook@redhat.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	linux-arch@vger.kernel.org,
	Linus Torvalds <torvalds@linux-foundation.org>,
	netdev@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>,
	ak@suse.de, heiko.carstens@de.ibm.com, davem@davemloft.net,
	schwidefsky@de.ibm.com, wensong@linux-vs.org, horms@verge.net.au,
	wjiang@resilience.com, cfriesen@nortel.com, zlynx@acm.org,
	rpjday@mindspring.com, jesper.juhl@gmail.com,
	segher@kernel.crashing.org
To: Paul Mackerras <paulus@samba.org>
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On Thu, 16 Aug 2007, Paul Mackerras wrote:

> 
> It seems that there could be a lot of places where atomic_t is used in
> a non-atomic fashion, and that those uses are either buggy, or there
> is some lock held at the time which guarantees that other CPUs aren't
> changing the value.  In both cases there is no point in using
> atomic_t; we might as well just use an ordinary int.

The point of atomic_t is to do atomic *changes* to the variable.