Message-ID: <4B2F2305.8030001@kernel.org>
Date: Mon, 21 Dec 2009 16:25:57 +0900
From: Tejun Heo <tj@kernel.org>
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To: Christoph Lameter <cl@linux-foundation.org>
CC: linux-kernel@vger.kernel.org, Mel Gorman <mel@csn.ul.ie>,
       Pekka Enberg <penberg@cs.helsinki.fi>,
       Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Subject: Re: [this_cpu_xx V8 09/16] Allow arch to provide inc/dec functionality
 for each size separately
References: <20091218222617.384355422@quilx.com> <20091218222652.446462888@quilx.com>
In-Reply-To: <20091218222652.446462888@quilx.com>
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On 12/19/2009 07:26 AM, Christoph Lameter wrote:
> Current this_cpu ops only allow an arch to specify add RMW operations or inc
> and dec for all sizes. Some arches can do more efficient inc and dec
> operations. Allow size specific override of fallback functions like with
> the other operations.

Wouldn't it be better to use __builtin_constant_p() and switching in
arch add/dec macros?  It just seems a bit extreme to define all those
different variants from generic header.  I'm quite unsure whether
providing overrides for all the different size variants from generic
header is necessary at all.  If an arch is gonna override the
operation, it's probably best to just let it override the whole thing.

Thanks.

-- 
tejun
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