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Date: Mon, 28 Apr 2008 18:47:50 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Linus Torvalds <torvalds@linux-foundation.org>
cc: Harvey Harrison <harvey.harrison@gmail.com>, Ingo Molnar <mingo@elte.hu>,
       Andrew Morton <akpm@linux-foundation.org>,
       LKML <linux-kernel@vger.kernel.org>, David Miller <davem@davemloft.net>
Subject: Re: [PATCH] bitops: simplify generic bit finding functions
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On Mon, 28 Apr 2008, Linus Torvalds wrote:
> >
> > How about making the optimization controlled by a config switch so
> > arch maintainers can decide whether they want to enable the constant
> > optimization or unconditionally call the lib function ?
> 
> No.
> 
> This is just making that damn header line look worse and worse.
> 
> Is there a _reason_ to optimize this stupid function this way?

On architectures which have a find bit instruction we can replace the
call to the library function by a single instruction when the size of
the bitmap is less/equal bits per long and when the bitnr is a
constant.

Thanks,
	tglx