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Subject: Re: [PATCH] RFC x86_64 more accurate KSTK_ESP implementation
From: Stefani Seibold <stefani@seibold.net>
To: Ingo Molnar <mingo@elte.hu>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@linux-foundation.org>,
       "H. Peter Anvin" <hpa@zytor.com>,
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Date: Sun, 08 Nov 2009 15:00:28 +0100
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Am Sonntag, den 08.11.2009, 13:55 +0100 schrieb Ingo Molnar:
> * Stefani Seibold <stefani@seibold.net> wrote:
> 
> > > I'd suggest a competely different method: why dont you use an IPI to 
> > > sample the SP whenever someone wants to read it from /proc and we 
> > > see that the task is running on a CPU right now?
> > 
> > Sounds like a challenge, i like the idea. I will have a look on it...
> 
> It's not a fastpath, so smp_function_call() ought to do the trick.
> 
> 	Ingo

There is no function smp_function_call()...