[PATCH tip/core/rcu 0/7] Post RCU callbacks at early boot

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

Hello!  

This series, probably for v3.21, contains changes that allow RCU callbacks
to be posted at very early boot, as in before rcu_init() is called.
This was requested by the tracing folks.  This series applies against
tip/core/rcu, and probably not against current mainline.

The patches in this series are as follows:

1.	Abstract initialization of callback lists.

2.	Wire up the rcu_state structures' ->rda pointers at compile time.

3.	Prevent early boot callbacks from splatting.

4.	Refine diagnostics for lacking an rcuo kthread for no-CBs
	CPUs that have callbacks posted.

5.	Avoid clobbering lists of early boot callbacks.

6.	Move early boot callbacks as needed by no-CBs CPUs.

7.	Move early boot callbacks tests to beginning of rcu_init().

This passes modest rcutorture testing, but is probably missing a corner
case or two.

							Thanx, Paul

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

 b/kernel/rcu/tree.c        |   52 ++++++++++++++++++++++++++++++++-------------
 b/kernel/rcu/tree_plugin.h |   27 ++++++++++++-----------
 2 files changed, 51 insertions(+), 28 deletions(-)