Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck...

Pull RCU update from Paul E. McKenney:

" [...] one late-breaking commit.  This one was requested for 3.15 by Peter Zijlstra.
  It is low risk because it adds a new in-kernel API with minimal changes to the
  existing code.  Those minimal changes are the addition of memory barriers and
  ACCESS_ONCE() macro calls, neither of which should be able to break things.
  This commit has passed significant rcutorture testing, with these additional
  additions to rcutorture slated for 3.16.  This commit has also been exposed to
  -next testing. "

Signed-off-by: Ingo Molnar <mingo@kernel.org>