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Date: Fri, 14 Oct 2005 20:04:14 +0200
From: Andi Kleen <ak@suse.de>
To: Chuck Ebbert <76306.1226@compuserve.com>
Cc: linux-kernel <linux-kernel@vger.kernel.org>, Andi Kleen <ak@suse.de>,
       Andrew Morton <akpm@osdl.org>, Linus Torvalds <torvalds@osdl.org>,
       Ingo Molnar <mingo@elte.hu>
Subject: Re: [patch 2.6.14-rc4] i386: spinlock optimization
Message-ID: <20051014180414.GD3502@verdi.suse.de>
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On Fri, Oct 14, 2005 at 01:47:09PM -0400, Chuck Ebbert wrote:
> Attempt to acquire spinlock sooner after spinning and then noticing
> it has become available.  Also adds a slight delay before testing the
> spinlock again when it's not available, reducing bus traffic.

I doubt your change adds any noticeable delay on a aggressive
OOO CPU, which are pretty much all modern x86s. It's probably
a nop.

-Andi