Re: [GIT PULL rcu/next + tools/memory-model] RCU and LKMM commits for 5.3

[Ingo Molnar <mingo@kernel.org>]

* Paul E. McKenney <paulmck@linux.ibm.com> wrote:

> Hello, Ingo,
> 
> This pull request contains the following changes:
> 
> 1.	RCU flavor consolidation cleanups and optmizations.
> 
> 	http://lkml.kernel.org/r/20190530145204.GA28526@linux.ibm.com
> 
> 2.	Documentation updates.
> 
> 	http://lkml.kernel.org/r/20190530145504.GA29820@linux.ibm.com
> 
> 3.	Miscellaneous fixes.
> 
> 	http://lkml.kernel.org/r/20190530145942.GA30318@linux.ibm.com
> 
> 4.	SRCU updates.
> 
> 	http://lkml.kernel.org/r/20190530150347.GA31311@linux.ibm.com
> 
> 5.	RCU-sync flavor consolidation.
> 
> 	http://lkml.kernel.org/r/20190530150816.GA32130@linux.ibm.com
> 
> 6.	Torture-test updates.
> 
> 	http://lkml.kernel.org/r/20190530151650.GA422@linux.ibm.com
> 
> 7.	Linux-kernel memory-consistency-model updates, most notably
> 	the addition of plain C-language accesses.
> 
> 	http://lkml.kernel.org/r/20190530144202.GA26201@linux.ibm.com
> 	http://lkml.kernel.org/r/Pine.LNX.4.44L0.1906201151210.1512-100000@iolanthe.rowland.org
> 	http://lkml.kernel.org/r/Pine.LNX.4.44L0.1906201152370.1512-100000@iolanthe.rowland.org
> 	http://lkml.kernel.org/r/Pine.LNX.4.44L0.1906201153470.1512-100000@iolanthe.rowland.org
> 
> 	These last three were relatively late additions responding to
> 	LKML feedback.	However, the resulting memory model passes its
> 	rather large library of tests, and these changes are furthermore
> 	required to correctly model some tricky situations involving
> 	use of RCU without rcu_assign_pointer() and rcu_dereference().
> 	These tricky sequences are not theoretical in nature, but rather
> 	from fixes identified by Herbert Xu.  It therefore seems best
> 	to get these upstream sooner rather than later.
> 
> 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 b989ff070574ad8b8621d866de0a8e9a65d42c80:
> 
>   Merge LKMM and RCU commits (2019-06-24 09:12:39 -0700)
> 
> These changes do increase the size of the kernel by about 300 lines.
> About 150 of this was due largely to improvements in rcutorture's
> forward-progress testing.  Not quite another 100 of this was due to
> allowing Tree SRCU to be used from modules without needing to adjust the
> size of the reserved region.  Not quite an additional 100 of this was for
> cleanups after the RCU flavor consolidation effort, including accidentally
> fixing a self-deadlock encountered by Sebastian Siewior when booting
> with the threadirqs kernel parameter.  Finally, yet another not quite
> 100 of this was for adding LKMM's support for plain C-language accesses.
> This totals to more than 300 because other changes removed code.
> 
> ----------------------------------------------------------------
> Alan Stern (7):
>       tools/memory-model: Prepare for data-race detection
>       tools/memory-model: Add definitions of plain and marked accesses
>       tools/memory-model: Add data-race detection
>       Documentation: atomic_t.txt: Explain ordering provided by smp_mb__{before,after}_atomic()
>       tools/memory-model: Expand definition of barrier
>       tools/memory-model: Change definition of rcu-fence
>       tools/memory-model: Improve data-race detection
> 
> Andrea Parri (3):
>       rcu: Don't return a value from rcu_assign_pointer()
>       tools/memory-model: Fix comment in MP+poonceonces.litmus
>       tools/memory-model: Do not use "herd" to refer to "herd7"
> 
> Jiang Biao (2):
>       rcu: Remove unused rdp local from synchronize_rcu_expedited()
>       rcu: Make __call_srcu static
> 
> Joel Fernandes (Google) (7):
>       lockdep: Add assertion to check if in an interrupt
>       rcu: Add checks for dynticks counters in rcu_is_cpu_rrupt_from_idle()
>       doc/rcuref: Document real world examples in kernel
>       srcu: Remove unused vmlinux srcu linker entries
>       module: Make srcu_struct ptr array as read-only
>       rcutorture: Select from only online CPUs
>       rcutorture: Add cpu0 to the set of CPUs to add jitter
> 
> Neeraj Upadhyay (2):
>       rcu: Dump specified number of blocked tasks
>       rcu: Correctly unlock root node in rcu_check_gp_start_stall()
> 
> Oleg Nesterov (4):
>       rcu/sync: Kill rcu_sync_type/gp_type
>       uprobes: Use DEFINE_STATIC_PERCPU_RWSEM() to initialize dup_mmap_sem
>       locking/percpu-rwsem: Add DEFINE_PERCPU_RWSEM(), use it to initialize cgroup_threadgroup_rwsem
>       rcu/sync: Simplify the state machine
> 
> Paul E. McKenney (34):
>       rcu: Check for wakeup-safe conditions in rcu_read_unlock_special()
>       rcu: Only do rcu_read_unlock_special() wakeups if expedited
>       rcu: Allow rcu_read_unlock_special() to raise_softirq() if in_irq()
>       rcu: Use irq_work to get scheduler's attention in clean context
>       rcu: Inline invoke_rcu_callbacks() into its sole remaining caller
>       rcu: Avoid self-IPI in sync_rcu_exp_select_node_cpus()
>       rcu: Avoid self-IPI in sync_sched_exp_online_cleanup()
>       rcu: Rename rcu_data's ->deferred_qs to ->exp_deferred_qs
>       rcu: Make kfree_rcu() ignore NULL pointers
>       rcu: Set a maximum limit for back-to-back callback invocation
>       doc: Remove ".vnet" from paulmck email addresses
>       srcu: Allocate per-CPU data for DEFINE_SRCU() in modules
>       rcutorture: Add cond_resched() to forward-progress free-up loop
>       rcutorture: Fix stutter_wait() return value and freelist checks
>       torture: Allow inter-stutter interval to be specified
>       torture: Make kvm-find-errors.sh and kvm-recheck.sh provide exit status
>       rcutorture: Provide rudimentary Makefile
>       rcutorture: Exempt tasks RCU from timely draining of grace periods
>       rcutorture: Exempt TREE01 from forward-progress testing
>       rcutorture: Give the scheduler a chance on PREEMPT && NO_HZ_FULL kernels
>       rcutorture: Halt forward-progress checks at end of run
>       rcutorture: Add trivial RCU implementation
>       torture: Capture qemu output
>       torture: Add function graph-tracing cheat sheet
>       torture: Run kernel build in source directory
>       torture: Make --cpus override idleness calculations
>       torture: Add --trust-make to suppress "make clean"
>       rcutorture: Dump trace buffer for callback pipe drain failures
>       torture: Suppress propagating trace_printk() warning
>       rcutorture: Upper case solves the case of the vanishing NULL pointer
>       rcu: Upgrade sync_exp_work_done() to smp_mb()
>       rcu: Fix irritating whitespace error in rcu_assign_pointer()
>       Merge branches 'consolidate.2019.05.28a', 'doc.2019.05.28a', 'fixes.2019.06.13a', 'srcu.2019.05.28a', 'sync.2019.05.28a' and 'torture.2019.05.28a' into HEAD
>       Merge LKMM and RCU commits
> 
> Sebastian Andrzej Siewior (2):
>       rcu: Enable elimination of Tree-RCU softirq processing
>       rcutorture: Tweak kvm options
> 
> Waiman Long (1):
>       rcu: Force inlining of rcu_read_lock()
> 
> Zhenzhong Duan (1):
>       doc: Fixup definition of rcupdate.rcu_task_stall_timeout
> 
>  Documentation/RCU/rcuref.txt                       |  21 +-
>  Documentation/RCU/stallwarn.txt                    |   2 +-
>  Documentation/RCU/whatisRCU.txt                    |   8 +-
>  Documentation/admin-guide/kernel-parameters.txt    |   6 +
>  Documentation/atomic_t.txt                         |  17 +-
>  Documentation/core-api/circular-buffers.rst        |   2 +-
>  Documentation/memory-barriers.txt                  |   2 +-
>  .../translations/ko_KR/memory-barriers.txt         |   2 +-
>  include/linux/lockdep.h                            |   7 +
>  include/linux/module.h                             |   5 +
>  include/linux/percpu-rwsem.h                       |  10 +-
>  include/linux/rcu_sync.h                           |  40 ++--
>  include/linux/rcupdate.h                           |  21 +-
>  include/linux/sched.h                              |   2 +-
>  include/linux/srcutree.h                           |  14 +-
>  include/linux/torture.h                            |   2 +-
>  kernel/cgroup/cgroup.c                             |   3 +-
>  kernel/events/uprobes.c                            |   4 +-
>  kernel/locking/locktorture.c                       |   2 +-
>  kernel/locking/percpu-rwsem.c                      |   2 +-
>  kernel/module.c                                    |   5 +
>  kernel/rcu/rcu.h                                   |   5 +
>  kernel/rcu/rcutorture.c                            |  96 +++++++--
>  kernel/rcu/srcutree.c                              |  69 ++++++-
>  kernel/rcu/sync.c                                  | 214 ++++++++++-----------
>  kernel/rcu/tree.c                                  | 164 +++++++++++++---
>  kernel/rcu/tree.h                                  |   6 +-
>  kernel/rcu/tree_exp.h                              |  53 +++--
>  kernel/rcu/tree_plugin.h                           | 195 ++++++-------------
>  kernel/rcu/tree_stall.h                            |   4 +-
>  kernel/rcu/update.c                                |  13 ++
>  kernel/torture.c                                   |  23 ++-
>  tools/include/linux/rcu.h                          |   4 +-
>  tools/memory-model/linux-kernel.bell               |   6 +
>  tools/memory-model/linux-kernel.cat                | 102 +++++++---
>  tools/memory-model/linux-kernel.def                |   1 +
>  .../litmus-tests/MP+poonceonces.litmus             |   2 +-
>  tools/memory-model/litmus-tests/README             |   2 +-
>  tools/memory-model/lock.cat                        |   2 +-
>  tools/memory-model/scripts/README                  |   4 +-
>  tools/memory-model/scripts/checkalllitmus.sh       |   2 +-
>  tools/memory-model/scripts/checklitmus.sh          |   2 +-
>  tools/memory-model/scripts/parseargs.sh            |   2 +-
>  tools/memory-model/scripts/runlitmushist.sh        |   2 +-
>  tools/testing/radix-tree/linux/rcupdate.h          |   2 +-
>  tools/testing/selftests/rcutorture/Makefile        |   3 +
>  .../testing/selftests/rcutorture/bin/configinit.sh |  39 ++--
>  tools/testing/selftests/rcutorture/bin/cpus2use.sh |   5 +
>  .../testing/selftests/rcutorture/bin/functions.sh  |  13 +-
>  tools/testing/selftests/rcutorture/bin/jitter.sh   |  13 +-
>  .../testing/selftests/rcutorture/bin/kvm-build.sh  |   9 +-
>  .../selftests/rcutorture/bin/kvm-find-errors.sh    |   3 +
>  .../selftests/rcutorture/bin/kvm-recheck.sh        |  13 +-
>  .../selftests/rcutorture/bin/kvm-test-1-run.sh     |  23 +--
>  tools/testing/selftests/rcutorture/bin/kvm.sh      |  14 +-
>  .../selftests/rcutorture/bin/parse-build.sh        |   2 +-
>  .../selftests/rcutorture/bin/parse-console.sh      |   1 +
>  .../selftests/rcutorture/configs/rcu/CFcommon      |   3 +
>  .../selftests/rcutorture/configs/rcu/TREE01.boot   |   1 +
>  .../selftests/rcutorture/configs/rcu/TRIVIAL       |  14 ++
>  .../selftests/rcutorture/configs/rcu/TRIVIAL.boot  |   3 +
>  61 files changed, 845 insertions(+), 466 deletions(-)
>  create mode 100644 tools/testing/selftests/rcutorture/Makefile
>  create mode 100644 tools/testing/selftests/rcutorture/configs/rcu/TRIVIAL
>  create mode 100644 tools/testing/selftests/rcutorture/configs/rcu/TRIVIAL.boot

Pulled, thanks a lot Paul!

	Ingo