[PATCH tip/core/rcu 0/9] CPU-hotplug updates for 4.2

["Paul E. McKenney" <paulmck@linux.vnet.ibm.com>]

Hello!

The following series improves RCU's handling of CPU hotplug.  It also
contains a couple of ARM placeholder patches in case someone gets caught
out by tighter diagnostics.

1.	Eliminate a HOTPLUG_CPU #ifdef in favor of IS_ENABLED()

2.	Adjust rcu_read_unlock_special()'s acquisition of the
	task's lock to start allowing for the fact that blocked
	tasks are no longer migrated to the root rcu_node structure.
	If the warning does not trigger, a later patch will eliminate
	the loop.

3.	Rmove dead code from force_qs_rnp().

4.	Remove redundant offline check.

5.	Correctly initialize ->rcu_qs_ctr_snap at online time to get the
	code out of its current "working by accident" state.

6.	Move smpboot_unpark_threads() handling into a notifier for
	uniformity.

7.	[Placeholder for ARM64]  Use common code for ARM64 CPU-offline
	notification.

8.	[Placeholder for ARM]  Use common code for ARM CPU-offline
	notification.

9.	Remove extraneous __cpuinit, courtesy of Paul Gortmaker.

							Thanx, Paul

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

 b/arch/arm/kernel/smp.c    |    6 +----
 b/arch/arm64/kernel/smp.c  |    6 +----
 b/kernel/cpu.c             |    4 +--
 b/kernel/rcu/tree.c        |   47 ++++++++++++++-------------------------------
 b/kernel/rcu/tree_plugin.h |    9 +++++---
 5 files changed, 27 insertions(+), 45 deletions(-)