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Date: Tue, 29 Nov 2011 12:45:59 +0530
From: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
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To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [RFC PATCH v2 1/4] cpuidle: (powerpc) Add cpu_idle_wait() to
 allow switching of idle routines
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On 11/29/2011 12:31 PM, Benjamin Herrenschmidt wrote:

> On Tue, 2011-11-29 at 12:12 +0530, Deepthi Dharwar wrote:
>>
>> Yes, this could be problematic as there is small window for the
>> race condition to occur . Otherwise we need to manually schedule
>> it by running a kernel thread but this would definitely have a
>> overhead and would be an overkill. 
> 
> Depends what this "window" is. IE. What are you trying to protect
> yourself against ? What's the risk ?
> 
> If it's just module unload, then stop_machine is probably your
> friend :-)
> 
> Cheers,
> Ben.
> 
> 


Yup, it is the module unload that I am worried about. Otherwise
manually doing it using kernel thread would be an overkill -:(

Regards,
Deepthi