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Date: Sun, 6 Jan 2002 19:34:36 -0800 (PST)
From: Linus Torvalds <torvalds@transmeta.com>
To: Davide Libenzi <davidel@xmailserver.org>
cc: Richard Henderson <rth@twiddle.net>, Alan Cox <alan@lxorguk.ukuu.org.uk>,
        Ingo Molnar <mingo@elte.hu>, lkml <linux-kernel@vger.kernel.org>
Subject: Re: [announce] [patch] ultra-scalable O(1) SMP and UP scheduler
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On Sun, 6 Jan 2002, Davide Libenzi wrote:
>
> 32 bit words lookup can be easily done in few clock cycles in most cpus
> by using tuned assembly code.

I tried to time "bsfl", it showed up as one cycle more than "nothing" on
my PII.

It used to be something like 7+n cycles on a i386, if I remember
correctly. It's just not an issue any more - trying to use clever code to
avoid it is just silly.

		Linus

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