From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [PATCH RFC -rt] updated synchronize_all_irqs implementation
Date: Wed, 26 Sep 2007 01:24:47 +0200
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Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
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To: Steven Rostedt <rostedt@goodmis.org>
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On Tue, 25 Sep 2007 16:02:45 -0400 (EDT) Steven Rostedt
<rostedt@goodmis.org> wrote:


> > This would of course require that synchronize_all_irqs() be in the
> > RCU code rather than the irq code so that it could access the static
> > wakeme_after_rcu() definition and the rcu_synchronize structure.
> >
> > Thoughts?
> >
> 
> I do like this better. Anyone else care to comment?
> 

I'm still wondering why the IRQ users cannot user proper RCU as it
stands:

  rcu_read_lock();
  foo = rcu_dereference(bar);
  if (foo)
    foo();
  rcu_read_unlock();

vs

  rcu_assign(foo, NULL);
  synchronize_rcu();

and the like.

The implicit rcu_read_lock() as placed in handle_IRQ_event() seems
misplaced.