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Subject: Re: [PATCH 01/13] powerpc: Add rcu_read_lock() to gup_fast()
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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Date: Fri, 16 Apr 2010 16:51:34 +1000
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On Mon, 2010-04-12 at 20:43 -0700, Paul E. McKenney wrote:
> > So we might have to support the interrupt assumption, at least in
> some
> > form, with those guys...
> 
> One way to make the interrupt assumption official is to use
> synchronize_sched() rather than synchronize_rcu().

Ok, so I'm a bit of a RCU newbie as you may know :-) Right now, we use
neither, we use call_rcu and we free the pages from the callback.

Ben.