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Date: Thu, 16 Aug 2007 13:05:03 +1000
From: Paul Mackerras <paulus@samba.org>
To: Satyam Sharma <satyam@infradead.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>,
       Christoph Lameter <clameter@sgi.com>,
       "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
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Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all
 architectures
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Satyam Sharma writes:

> I can't speak for this particular case, but there could be similar code
> examples elsewhere, where we do the atomic ops on an atomic_t object
> inside a higher-level locking scheme that would take care of the kind of
> problem you're referring to here. It would be useful for such or similar
> code if the compiler kept the value of that atomic object in a register.

If there is a higher-level locking scheme then there is no point to
using atomic_t variables.  Atomic_t is specifically for the situation
where multiple CPUs are updating a variable without locking.

Paul.
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