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Date: Wed, 7 May 2008 15:35:38 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andi Kleen <andi@firstfloor.org>, Matthew Wilcox <matthew@wil.cx>,
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       Alexander Viro <viro@ftp.linux.org.uk>,
       Andrew Morton <akpm@linux-foundation.org>
Subject: Re: AIM7 40% regression with 2.6.26-rc1
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> But my preferred option would indeed be just turning it back into a 
> spinlock - and screw latency and BKL preemption - and having the RT people 
> who care deeply just work on removing the BKL in the long run.

It isn't as if the RT build can't use a different lock type to the
default build.

> Is BKL preemption worth it? Sounds very dubious. Sounds even more dubious 
> when we now apparently have even more reason to aim for removing the BKL 
> rather than trying to mess around with it.

We have some horrible long lasting BKL users left unfortunately.

Alan