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Message-ID: <4D0CCA77.2040701@kernel.org>
Date: Sat, 18 Dec 2010 15:51:35 +0100
From: Tejun Heo <tj@kernel.org>
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To: Christoph Lameter <cl@linux.com>
CC: akpm@linux-foundation.org, Pekka Enberg <penberg@cs.helsinki.fi>,
        linux-kernel@vger.kernel.org, Eric Dumazet <eric.dumazet@gmail.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Subject: Re: [cpuops cmpxchg double V1 1/4] Generic support for this_cpu_cmpxchg_double
References: <20101214174847.887713690@linux.com> <20101214174900.058235985@linux.com> <4D0CC982.3030905@kernel.org>
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On 12/18/2010 03:47 PM, Tejun Heo wrote:
> This is ugly. :-( I think we should have made this_cpu_*() ops take
> pointers from the beginning.  Anyways, that's too late, so is it
> completely impossible to make cmpxchg_double's take a scalar value?
> It can take the pointer all the same, no?

Also, the ratonale behind taking a scalar value instead of pointer was
that the operation changes what they do depending on the type of the
parameter (the size of the parameter), which is true for the double
ops too, so I think it would be better if we stick with lvalues.

Thanks.

-- 
tejun