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Date: Mon, 16 Jul 2007 11:26:46 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Nick Piggin <npiggin@suse.de>
Cc: Andi Kleen <ak@suse.de>, Linus Torvalds <torvalds@linux-foundation.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [rfc][patch 2/2] x86_64: FIFO ticket spinlocks
Message-ID: <20070716092646.GA18423@elte.hu>
References: <20070716045932.GA19914@wotan.suse.de> <20070716050134.GB19914@wotan.suse.de>
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* Nick Piggin <npiggin@suse.de> wrote:

> [...] trylock is more significantly slower, but they are relatively 
> rare.

trylock is the main thing that the spinlock debugging code uses, and 
SPINLOCK_DEBUG is frequently enabled by distro kernels. OTOH, the cost 
looks like to be +5 instructions, right? Still ...

	Ingo