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Subject: Re: [PATCH rcu/urgent 0/6] Fixes for RCU/scheduler/irq-threads
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From: Peter Zijlstra <peterz@infradead.org>
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Date: Wed, 20 Jul 2011 23:05:53 +0200
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On Wed, 2011-07-20 at 12:29 -0700, Paul E. McKenney wrote:

> Peter, does #4 (protect __rcu_read_unlock() against scheduler-using
> irq handlers) remove the need for #5 (Add irq_{enter,exit}() to
> scheduler_ipi()) and #6 (Inform RCU of irq_exit() activity)?  My guess is
> "no" for #5 and "yes" for #6.

More or less, we want to keep #5 for it does more than just fix RCU, but
yeah, I _think_ #4 obsoletes the direct need for #6.