Pull RCU changes from Paul E. McKenney:
- Expedited grace-period changes, most notably avoiding having
user threads drive expedited grace periods, using a workqueue
instead.
- Miscellaneous fixes, including a performance fix for lists
that was sent with the lists modifications (second URL below).
- CPU hotplug updates, most notably providing exact CPU-online
tracking for RCU. This will in turn allow removal of the
checks supporting RCU's prior heuristic that was based on the
assumption that CPUs would take no longer than one jiffy to
come online.
- Torture-test updates.
- Documentation updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>