[PATCH] rcu: Allow calls to rcu_exit_user_irq from nesting irqs

[Frederic Weisbecker]

On Tue, Jun 05, 2012 at 04:46:40PM -0700, Paul E. McKenney wrote:
> Here you go:
> 
> git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git rcu/idle

So I've rebased my nohz cpusets patchset and applied these patches.
During testing I found a bug and realized I need to make rcu_exit_user_irq()
callable from any irq nesting level.

Here is a fix:

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