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To: linux-kernel@vger.kernel.org, rogelio.serrano@gmail.com
Date: Tue, 23 Dec 2014 03:08:10 +0100
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Subject: Re: atomic_inc and spin_lock_irq
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On 18 Dec 2014 at 21:07, Rogelio M. Serrano Jr. wrote:

> whats the difference between:
> 
> atomic_inc(&port->count);
> 
> and
> 
> spin_lock_irq(&port->lock);
> ++port->count;
> spin_unlock_irq(&port->lock);

in PaX this kind of change brings the ->count accesses under the coverage
of the REFCOUNT feature. if the kernel had a non-atomic refcount type and
corresponding accessors, they'd be used here instead.