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Date: Tue, 20 Dec 2005 10:27:12 -0800 (PST)
From: Linus Torvalds <torvalds@osdl.org>
To: Nicolas Pitre <nico@cam.org>
cc: Nick Piggin <nickpiggin@yahoo.com.au>, Ingo Molnar <mingo@elte.hu>,
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Subject: Re: [patch 04/15] Generic Mutex Subsystem, add-atomic-call-func-x86_64.patch
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On Tue, 20 Dec 2005, Nicolas Pitre wrote:
>
> Sure, and we're now more costly than the current implementation with irq 
> disabling.

Do the timing. It may be more instructions, but I think it was you 
yourself that timed the current thing at 23 cycles, no?

Special registers are almost always slower than nicely cached accesses 
(and they all basically will be).

		Linus
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