Expedited grace-period changes for 4.7

Hello!

This series contains updates for RCU's expedited grace-period facility:

1. Make expedited RCU-sched grace period immediately detect idle.

2. Make expedited RCU-preempt stall warnings count accurately.

3. Make cond_resched_rcu_qs() supply RCU-sched expedited QS.

4. Fix synchronize_rcu_expedited() header comment.

5. Add event tracing definitions for expedited grace periods.

6. Add funnel-locking tracing for expedited grace periods.

7. Add expedited-grace-period event tracing.

8. Remove expedited GP funnel-lock bypass.

9. Force boolean subscript for expedited stall warnings.

10. Shorten expedited_workdone* to exp_workdone*.

11. Enforce expedited-GP fairness via funnel wait queue.

12. Add exp_funnel_lock() fastpath for new funnel wait queue.

13. Consolidate expedited GP code into rcu_exp_wait_wake().

14. Consolidate expedited GP tracing into rcu_exp_gp_seq_snap().

15. Consolidate expedited GP code into exp_funnel_lock().

16. Overlap wakeups with next expedited grace period.

Thanx, Paul

------------------------------------------------------------------------

 Documentation/RCU/trace.txt |   10 -
 include/trace/events/rcu.h  |   83 ++++++++++-
 kernel/rcu/tree.c           |  317 +++++++++++++++++++++++++-------------------
 kernel/rcu/tree.h           |   20 +-
 kernel/rcu/tree_plugin.h    |   57 +++----
 kernel/rcu/tree_trace.c     |   13 -
 6 files changed, 312 insertions(+), 188 deletions(-)