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Message-ID: <1424812311.12891.51.camel@kernel.crashing.org>
Subject: Re: [PATCH] powerpc: Export __spin_yield
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "Suresh E. Warrier" <warrier@linux.vnet.ibm.com>
Date: Wed, 25 Feb 2015 08:11:51 +1100
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On Tue, 2015-02-24 at 10:37 -0600, Suresh E. Warrier wrote:
> 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?

Nope. Not sure how come we did that.

> 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()?

What kind of module might need it...

Cheers,
Ben.