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Date: Sun, 08 Nov 2009 08:34:43 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Stefani Seibold <stefani@seibold.net>
CC: Ingo Molnar <mingo@elte.hu>, linux-kernel <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@linux-foundation.org>,
       Americo Wang <xiyou.wangcong@gmail.com>,
       Thomas Gleixner <tglx@linutronix.de>, Andi Kleen <andi@firstfloor.org>
Subject: Re: [PATCH] RFC x86_64 more accurate KSTK_ESP implementation
References: <1257233486.22553.6.camel@wall-e>	 <20091103082843.GA27676@elte.hu> <1257239184.4889.15.camel@wall-e>	 <1257409189.26874.18.camel@wall-e> <20091108113546.GN11372@elte.hu>	 <1257684666.20579.9.camel@wall-e>  <20091108125527.GA19350@elte.hu> <1257688828.23062.0.camel@wall-e>
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On 11/08/2009 06:00 AM, Stefani Seibold wrote:
> 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.
> 
> There is no function smp_function_call()...
> 

smp_call_function().

	-hpa


-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.