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Subject: Re: [patch] IBM HDAPS accelerometer driver, with probing.
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Robert Love <rml@novell.com>, dtor_core@ameritech.net,
       Andrew Morton <akpm@osdl.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Date: Sat, 27 Aug 2005 15:45:52 +0100
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On Sad, 2005-08-27 at 02:29 -0300, Arnaldo Carvalho de Melo wrote:
> > unlikely() can result in better, smaller, faster code.  and it acts as a
> > nice directive to programmers reading the code.
> 
> Agreed, keep them :-)

If the unlikely() hints are being used correctly and the compiler is
doing the right thing then it ought to be worthwhile, if not then fix
the compiler.

Remember however unlikely() does have a code size cost on some
processors and a small performance cost so it really has to mean
very_unlikely().