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Date: Tue, 24 Feb 2015 10:37:47 -0600
From: "Suresh E. Warrier" <warrier@linux.vnet.ibm.com>
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To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [PATCH] powerpc: Export __spin_yield
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On 02/23/2015 09:38 PM, Benjamin Herrenschmidt wrote:
> On Mon, 2015-02-23 at 18:10 -0600, Suresh E. Warrier wrote:
>> Export __spin_yield so that the arch_spin_unlock() function
>> can be invoked from a module.
> 
> Make it EXPORT_SYMBOL_GPL. Also explain why a module might need it
> 

Sure, I will change that to EXPORT_SYMBOL_GPL. Just curious, though, 
there is another symbol arch_spin_unlock_wait that is exported from
the file without the _GPL prefix. Any idea why?

I have mentioned that this needs to be exported to call the 
arch_spin_unlock() function from a module. What additional information
do you think will be useful here ? Are you looking at something
that explains why a module might need to call arch_spin_unlock()?

Thanks.
-suresh