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Subject: Re: [PATCH 01/13] powerpc: Add rcu_read_lock() to gup_fast()
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Date: Wed, 14 Apr 2010 15:51:50 +0200
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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().

Well, call_rcu_sched() then, because the current usage is to use
call_rcu() to free the page directories.

Paul, here is a call_rcu_sched() available in kernel/rcutree.c, but am I
right in reading that code that that would not be available for
preemptible RCU?