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Date: Fri, 02 Sep 2005 18:05:49 +1000
From: Nick Piggin <nickpiggin@yahoo.com.au>
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To: "David S. Miller" <davem@davemloft.net>
Cc: linux-arch@vger.kernel.org
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David S. Miller wrote:
> Sparc32 lacks compare and exchange.  I think PARISC lacks it
> as well.
> 
> For these older SMP systems, at best you can assume there
> is some kind of spinlock and perhaps a straight atomic
> exchange instruction.  You really can't assume the existance
> of compare-and-swap.
> 

Thanks David, I suspected as much.

PARISC emulates cmpxchg. I suspect sparc could do the same?
(provided all access goes through the atomic_xxx accessors)

Nick

-- 
SUSE Labs, Novell Inc.

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