commit 8db559b83009bed92e1b5dd13a651ff273d9ff62
author Paul E. McKenney <paulmck@linux.vnet.ibm.com> Mon May 12 21:21:05 2008 +0200
committer Ingo Molnar <mingo@elte.hu> Mon May 19 10:01:36 2008 +0200
tree b25e521434747cc11e958a71ad24c47117db4e08
parent 4446a36ff8c74ac3b32feb009b651048e129c6af

rcu: add memory barriers and comments to rcu_check_callbacks()

Add comments to the logic that infers quiescent states when interrupting
from either user mode or the idle loop.  Also add a memory barrier: it
appears that James Huang was in fact onto something, as the scheduler
is much less synchronization happy than it once was, so we can no longer
rely on its memory barriers in all cases.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reported-by: James Huang <jamesclhuang@yahoo.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>