[GIT PULL] locking changes for v5.8

[Ingo Molnar]

Linus,

Please pull the latest locking/core git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git locking-core-2020-06-01

   # HEAD: 19f545b6e07f753c4dc639c2f0ab52345733b6a8 zram: Use local lock to protect per-CPU data

The biggest change to core locking facilities in this cycle is the introduction
of local_lock_t - this primitive comes from the -rt project and identifies
CPU-local locking dependencies normally handled opaquely beind preempt_disable()
or local_irq_save/disable() critical sections.

The generated code on mainline kernels doesn't change as a result, but still there
are benefits: improved debugging and better documentation of data structure
accesses.

The new local_lock_t primitives are introduced and then utilized in a couple of
kernel subsystems. No change in functionality is intended.

There's also other smaller changes and cleanups.

 Thanks,

	Ingo

------------------>
Alex Shi (1):
      locking/rtmutex: Remove unused rt_mutex_cmpxchg_relaxed()

Gustavo A. R. Silva (1):
      locking/lockdep: Replace zero-length array with flexible-array

Ingo Molnar (1):
      mm/swap: Use local_lock for protection

Julia Cartwright (1):
      squashfs: Make use of local lock in multi_cpu decompressor

Mike Galbraith (2):
      connector/cn_proc: Protect send_msg() with a local lock
      zram: Use local lock to protect per-CPU data

Sebastian Andrzej Siewior (2):
      radix-tree: Use local_lock for protection
      zram: Allocate struct zcomp_strm as per-CPU memory

Thomas Gleixner (1):
      locking: Introduce local_lock()


 Documentation/locking/locktypes.rst     | 215 ++++++++++++++++++++++++++++++--
 drivers/block/zram/zcomp.c              |  44 +++----
 drivers/block/zram/zcomp.h              |   5 +-
 drivers/connector/cn_proc.c             |  21 ++--
 fs/squashfs/decompressor_multi_percpu.c |  21 ++--
 include/linux/idr.h                     |   2 +-
 include/linux/local_lock.h              |  54 ++++++++
 include/linux/local_lock_internal.h     |  90 +++++++++++++
 include/linux/radix-tree.h              |  11 +-
 include/linux/swap.h                    |   1 +
 kernel/locking/lockdep.c                |   2 +-
 kernel/locking/rtmutex.c                |   2 -
 lib/radix-tree.c                        |  20 ++-
 mm/compaction.c                         |   6 +-
 mm/swap.c                               | 118 ++++++++++++------
 15 files changed, 502 insertions(+), 110 deletions(-)
 create mode 100644 include/linux/local_lock.h
 create mode 100644 include/linux/local_lock_internal.h