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Date: Sat, 1 Dec 2001 15:37:23 -0800 (PST)
From: Davide Libenzi <davidel@xmailserver.org>
X-X-Sender: davide@blue1.dev.mcafeelabs.com
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
cc: lkml <linux-kernel@vger.kernel.org>,
        Shuji YAMAMURA <yamamura@flab.fujitsu.co.jp>
Subject: Re: [PATCH] task_struct colouring ...
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On Sat, 1 Dec 2001, Alan Cox wrote:

> > The point is why store kernel pointers in global registers when You can
> > achieve the same functionality, with a smaller patch, that does not need
> > to be recoded for each CPU, without using global registers.
>
> Because it is much much much faster

We'll see how much faster is the global register allocation against code
like :

movl %esp, %eax
andl $-8192, %eax
movl (%eax), %eax

Because you can justify a global register allocation only if this "much
much faster" translates to a number that has sense.




- Davide




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