[GIT PULL rcu/next] RCU commits for 4.5

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

Hello, Ingo,

The changes in this series include the following:

1.	Adding transitivity uniformly to rcu_node structure ->lock
	acquisitions.  (This is implemented by the first two commits
	on top of v4.4-rc2 due to the pervasive nature of this change.)

	http://article.gmane.org/gmane.linux.kernel/2100835

2.	Documentation updates, including RCU requirements.

	http://article.gmane.org/gmane.linux.kernel/2104628

3.	Expedited grace-period changes.

	http://article.gmane.org/gmane.linux.kernel/2104595

4.	Miscellaneous fixes.

	http://article.gmane.org/gmane.linux.kernel/2104612

5.	Linked-list fixes, courtesy of KTSAN.

	http://article.gmane.org/gmane.linux.kernel/2100875

6.	Torture-test updates.

	http://article.gmane.org/gmane.linux.kernel/2104652

7.	Late-breaking fix to sysrq-generated crash.

	http://article.gmane.org/gmane.linux.kernel/2111676

All of these changes have been subjected to 0day Test Robot and -next
testing, and are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git for-mingo

for you to fetch changes up to 984cf355aeaa8f2eda3861b50d0e8d3e3f77e83b:

  sysrq: Fix warning in sysrq generated crash. (2015-12-29 16:29:18 -0800)

----------------------------------------------------------------
Alexey Kardashevskiy (2):
      rcu: Fix comment for rcu_dereference_raw_notrace
      list: Add lockless list traversal primitives

Ani Sinha (1):
      sysrq: Fix warning in sysrq generated crash.

Chris Metcalf (1):
      Documentation/memory-barriers.txt: Fix ACCESS_ONCE thinko

Paul E. McKenney (41):
      list: Use WRITE_ONCE() when adding to lists and hlists
      list: Use READ_ONCE() when testing for empty lists
      rcu: Add transitivity to remaining rcu_node ->lock acquisitions
      rcu: Short-circuit synchronize_sched_expedited() if only one CPU
      rcu: Clarify role of ->expmaskinitnext
      rcu: Move smp_mb() from rcu_seq_snap() to rcu_exp_gp_seq_snap()
      rcu: Invert sync_rcu_exp_select_cpus() "if" statement
      rcu: Reduce expedited GP memory contention via per-CPU variables
      rcu: Make expedited grace periods resolve stall-warning ties
      rcu: Add more diagnostics to expedited stall warning messages.
      rcu: Add rcu_normal kernel parameter to suppress expediting
      rcu: Wire up rcu_end_inkernel_boot()
      rcu: Allow expedited grace periods to be disabled at init
      rcu: Move lock_class_key to local scope
      rcu: Simplify rcu_sched_qs() control flow
      rcu: Remove lock-acquisition loop from rcu_read_unlock_special()
      rcu: Fix obsolete rcu_bootup_announce_oddness() comment
      rcu: Avoid tick_nohz_active checks on NOCBs CPUs
      rcu: Stop disabling interrupts in scheduler fastpaths
      list: Use WRITE_ONCE() when initializing list_head structures
      documentation: Record RCU requirements
      Documentation: Record bottom-bit-zero guarantee for ->next
      documentation: Cover requirements controlling stall warnings
      documentation: Composability analogies
      documentation: Expand on scheduler/RCU deadlock requirements
      documentation: Clarify RCU memory barriers and requirements
      documentation: Update RCU requirements based on expedited changes
      rcutorture: Add batch number to script printout
      rcutorture: Flag nonexistent RCU GP kthread
      rcutorture:  Dump stack when GP kthread stalls
      rcutorture: Default grace period to three minutes, allow override
      rcutorture: Print symbolic name for rcu_torture_writer_state
      rcutorture: Print symbolic name for ->gp_state
      torture: Abbreviate console error dump
      torture: Place console.log files correctly from the get-go
      rcu: Remove TINY_RCU bloat from pointless boot parameters
      rcu: Eliminate unused rcu_init_one() argument
      rcu: Make cpu_needs_another_gp() be bool
      rcu: Don't redundantly disable irqs in rcu_irq_{enter,exit}()
      rcu: Make rcu_gp_init() be bool rather than int
      Merge branches 'doc.2015.12.05a', 'exp.2015.12.07a', 'fixes.2015.12.07a', 'list.2015.12.04b' and 'torture.2015.12.05a' into HEAD

Paul Gortmaker (1):
      kernel: Make rcu/tree_trace.c explicitly non-modular

Peter Zijlstra (2):
      rcu: Create transitive rnp->lock acquisition functions
      rcu: Move wakeup out from under rnp->lock

Petko Manolov (1):
      list: Introduces generic list_splice_tail_init_rcu()

Yang Shi (1):
      rcutorture: Remove CONFIG_RCU_USER_QS from rcutorture selftest doc

 .../RCU/Design/Requirements/2013-08-is-it-dead.png |  Bin 0 -> 100825 bytes
 .../Design/Requirements/GPpartitionReaders1.svg    |  374 +++
 .../RCU/Design/Requirements/RCUApplicability.svg   |  237 ++
 .../Design/Requirements/ReadersPartitionGP1.svg    |  639 +++++
 .../RCU/Design/Requirements/Requirements.html      | 2897 ++++++++++++++++++++
 .../RCU/Design/Requirements/Requirements.htmlx     | 2741 ++++++++++++++++++
 Documentation/RCU/Design/htmlqqz.sh                |  108 +
 Documentation/kernel-parameters.txt                |   29 +-
 Documentation/memory-barriers.txt                  |    8 +-
 drivers/tty/sysrq.c                                |    6 +
 include/linux/list.h                               |   14 +-
 include/linux/list_bl.h                            |    2 +-
 include/linux/list_nulls.h                         |    2 +-
 include/linux/rculist.h                            |  105 +-
 include/linux/rcupdate.h                           |   21 +-
 include/linux/rcutiny.h                            |    8 +
 include/linux/rcutree.h                            |    4 +-
 include/linux/tracepoint.h                         |    4 +-
 init/main.c                                        |    2 +
 kernel/ksysfs.c                                    |   26 +-
 kernel/rcu/rcutorture.c                            |   24 +-
 kernel/rcu/srcu.c                                  |    2 +-
 kernel/rcu/tree.c                                  |  313 ++-
 kernel/rcu/tree.h                                  |   61 +-
 kernel/rcu/tree_plugin.h                           |   66 +-
 kernel/rcu/tree_trace.c                            |   39 +-
 kernel/rcu/update.c                                |   22 +-
 kernel/sched/core.c                                |    6 +-
 lib/list_debug.c                                   |    2 +-
 .../selftests/rcutorture/bin/kvm-test-1-run.sh     |    9 +-
 tools/testing/selftests/rcutorture/bin/kvm.sh      |   22 +-
 .../selftests/rcutorture/bin/parse-console.sh      |   41 +-
 .../testing/selftests/rcutorture/doc/TINY_RCU.txt  |    1 -
 .../selftests/rcutorture/doc/TREE_RCU-kconfig.txt  |    4 -
 34 files changed, 7552 insertions(+), 287 deletions(-)
 create mode 100644 Documentation/RCU/Design/Requirements/2013-08-is-it-dead.png
 create mode 100644 Documentation/RCU/Design/Requirements/GPpartitionReaders1.svg
 create mode 100644 Documentation/RCU/Design/Requirements/RCUApplicability.svg
 create mode 100644 Documentation/RCU/Design/Requirements/ReadersPartitionGP1.svg
 create mode 100644 Documentation/RCU/Design/Requirements/Requirements.html
 create mode 100644 Documentation/RCU/Design/Requirements/Requirements.htmlx
 create mode 100755 Documentation/RCU/Design/htmlqqz.sh