From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [RFC][PATCH 0/5] preempt_count rework
Date: Wed, 14 Aug 2013 08:43:12 -0700
Message-ID: <520BA590.2030808@zytor.com>
References: <20130814131539.790947874@chello.nl>  <520B8A81.1080405@zytor.com> <1376494751.7355.28.camel@marge.simpson.net>
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To: Mike Galbraith <bitbucket@online.de>
Cc: Peter Zijlstra <peterz@infradead.org>, Linus Torvalds <torvalds@linux-foundation.org>, Ingo Molnar <mingo@kernel.org>, Andi Kleen <ak@linux.intel.com>, Thomas Gleixner <tglx@linutronix.de>, Arjan van de Ven <arjan@linux.intel.com>, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org

On 08/14/2013 08:39 AM, Mike Galbraith wrote:
> 
> ..so could the rq = cpu_rq(cpu) sequence be improved cycle expenditure
> wise by squirreling rq pointer away in a percpu this_rq, and replacing
> cpu_rq(cpu) above with a __this_cpu_read(this_rq) version of this_rq()?
> 

Yes.

	-hpa