RCU commits for 3.8

Hello, Ingo,

The major features of this series are:

1. A first version of no-callbacks CPUs. This version prohibits
offlining CPU 0, but only when enabled via CONFIG_RCU_NOCB_CPU=y. Relaxing this constraint is in progress, but not yet ready for prime time. These commits were posted to LKML at
https://lkml.org/lkml/2012/10/30/724, and are at branch rcu/nocb.

2. Changes to SRCU that allows statically initialized srcu_struct

	structures.  These commits were posted to LKML at
	https://lkml.org/lkml/2012/10/30/296, and are at branch rcu/srcu.

3. Restructuring of RCU's debugfs output. These commits were posted

	to LKML at https://lkml.org/lkml/2012/10/30/341, and are at
	branch rcu/tracing.

4. Additional CPU-hotplug/RCU improvements, posted to LKML at
https://lkml.org/lkml/2012/10/30/327, and are at branch rcu/hotplug. Note that the commit eliminating __stop_machine() was judged to be too-high of risk, so is deferred to 3.9.

5. Changes to RCU's idle interface, most notably a new module
parameter that redirects normal grace-period operations to their expedited equivalents. These were posted to LKML at
https://lkml.org/lkml/2012/10/30/739, and are at branch rcu/idle.

6. Additional diagnostics for RCU's CPU stall warning facility,
posted to LKML at https://lkml.org/lkml/2012/10/30/315, and are at branch rcu/stall. The most notable change reduces the default RCU CPU stall-warning time from 60 seconds to 21 seconds, so that it once again happens sooner than the softlockup timeout.

7. Documentation updates, which were posted to LKML at

	https://lkml.org/lkml/2012/10/30/280, and are at branch rcu/doc.
	A couple of late-breaking changes were posted at
	https://lkml.org/lkml/2012/11/16/634 and
	https://lkml.org/lkml/2012/11/16/547.

8. Miscellaneous fixes, which were posted to LKML at

	https://lkml.org/lkml/2012/10/30/309, along with a late-breaking
	change posted at Fri, 16 Nov 2012 11:26:25 -0800 with message-ID
	<[email protected]>, but which lkml.org
	seems to have missed.  These are at branch rcu/fixes.

9. Finally, a fix for an lockdep-RCU splat was posted to LKML

	at https://lkml.org/lkml/2012/11/7/486.  This is at rcu/next.

All executable code in these commits have been subject to -next testing. (Fixes to trailing whitespace problems in one of the Documentation files has not yet been, but as far as I know -next testing does not do anything with Documentation files -- and testing will happen as soon as -next testing restarts.)

These changes are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git rcu/next

Thanx, Paul

------------------>
Antti P Miettinen (1):
rcu: Add a module parameter to force use of expedited RCU primitives

Dhaval Giani (1):
rcu: Correct the name of a reference in list of RCU papers

Eric Dumazet (1):
rcu: Fix batch-limit size problem

Frederic Weisbecker (2):
rcu: Remove rcu_switch()
rcu: Fix unrecovered RCU user mode in syscall_trace_leave()

Kees Cook (1):
rcu: Update docs to include kfree_rcu()

Lai Jiangshan (4):
srcu: Credit Lai Jiangshan with SRCU rewrite
srcu: Export process_srcu()
srcu: Add DEFINE_SRCU()
rcutorture: Use DEFINE_STATIC_SRCU()

Michael Wang (12):
rcu: Create directory for each flavor of rcu
rcu: Fundamental facility for 'CPU units sequence reading'
rcu: Optimize the 'rcudata' for RCU trace
rcu: Optimize the 'rcudata.csv' for RCU trace
rcu: Optimize the 'rcu_pending' for RCU trace
rcu: Replace the old interface with the new one
rcu: Remove the interface "rcudata.csv"
rcu: split 'rcubarrier' to each flavor
rcu: split 'rcuboost' to each flavor
rcu: split 'rcugp' to each flavor
rcu: split 'rcuhier' to each flavor
rcu: Remove old debugfs interfaces and also RCU flavor name

Paul E. McKenney (27):
rcu: Accelerate callbacks for CPU initiating a grace period
Documentation: Fix memory-barriers.txt example
rcu: Fix comment about _rcu_barrier()/orphanage exclusion
rcu: Make rcutorture give diagnostics if CPU offline fails
rcu: Update RCU_FAST_NO_HZ help text
rcu: Fix precedence error in cpu_needs_another_gp()
rcu: Print remote CPU's stacks in stall warnings
rcu: Add grace-period information to RCU CPU stall warnings
rcu: Dump number of callbacks in stall warning messages
rcu: Document alternative RCU/reference-count algorithms
rcu: Rename ->onofflock to ->orphan_lock
rcu: Avoid counter wrap in synchronize_sched_expedited()
rcu: Move synchronize_sched_expedited() state to rcu_state
rcu: Instrument synchronize_rcu_expedited() for debugfs tracing
rcu: Fix tracing formatting
rcu: Add tracing for synchronize_sched_expedited()
rcu: Remove list_for_each_continue_rcu()
rcu: Add new rcutorture module parameters to start/end test messages
rcu: Clarify memory-ordering properties of grace-period primitives
rcu: Fix TINY_RCU rcu_is_cpu_rrupt_from_idle check
rcu: Reduce default RCU CPU stall warning timeout
rcu: Update documentation for TREE_RCU debugfs tracing
rcu: Add documentation for the new rcuexp debugfs trace file
Merge branches 'urgent.2012.10.27a', 'doc.2012.11.16a', 'fixes.2012.11.13a', 'srcu.2012.10.27a', 'stall.2012.11.13a', 'tracing.2012.11.08a' and 'idle.2012.10.24a' into HEAD
rcu: Add callback-free CPUs
rcu: Separate accounting of callbacks from callback-free CPUs
sched: Mark RCU reader in sched_show_task()

Paul Gortmaker (1):
rcu: Wordsmith help text for RCU_USER_QS kernel parameter

 Documentation/RCU/RTFP.txt          |    2 +-
 Documentation/RCU/checklist.txt     |   17 +-
 Documentation/RCU/listRCU.txt       |    2 +-
 Documentation/RCU/rcuref.txt        |   61 +++++-
 Documentation/RCU/trace.txt         |  396 ++++++++++++++++++---------------
 Documentation/RCU/whatisRCU.txt     |   17 +-
 Documentation/kernel-parameters.txt |   21 ++
 Documentation/memory-barriers.txt   |    9 +-
 arch/um/drivers/mconsole_kern.c     |    2 +-
 arch/x86/kernel/ptrace.c            |    7 +
 include/linux/rculist.h             |   17 --
 include/linux/rcupdate.h            |   27 +++
 include/linux/sched.h               |   10 +-
 include/linux/srcu.h                |   34 +++
 include/trace/events/rcu.h          |    1 +
 init/Kconfig                        |   41 +++-
 kernel/ksysfs.c                     |   18 ++
 kernel/rcu.h                        |    2 +
 kernel/rcupdate.c                   |    3 +
 kernel/rcutiny.c                    |    2 +-
 kernel/rcutiny_plugin.h             |    5 +-
 kernel/rcutorture.c                 |   54 ++---
 kernel/rcutree.c                    |  283 ++++++++++++++++++------
 kernel/rcutree.h                    |   67 ++++++-
 kernel/rcutree_plugin.h             |  415 ++++++++++++++++++++++++++++++++++-
 kernel/rcutree_trace.c              |  330 ++++++++++++++--------------
 kernel/sched/core.c                 |   14 +-
 kernel/srcu.c                       |   16 +-
 lib/Kconfig.debug                   |    2 +-
 29 files changed, 1352 insertions(+), 523 deletions(-)

Pulled into tip:core/rcu, thanks a lot Paul!

There was a minor conflict in arch/x86/kernel/ptrace.c that I've resolved.

Thanks,

Ingo