Pull locking updates from Ingo Molnar:

 - Core locking & atomics:

     - Convert all architectures to ARCH_ATOMIC: move every architecture
       to ARCH_ATOMIC, then get rid of ARCH_ATOMIC and all the
       transitory facilities and #ifdefs.

       Much reduction in complexity from that series:

           63 files changed, 756 insertions(+), 4094 deletions(-)

     - Self-test enhancements

 - Futexes:

     - Add the new FUTEX_LOCK_PI2 ABI, which is a variant that doesn't
       set FLAGS_CLOCKRT (.e. uses CLOCK_MONOTONIC).

       [ The temptation to repurpose FUTEX_LOCK_PI's implicit setting of
         FLAGS_CLOCKRT & invert the flag's meaning to avoid having to
         introduce a new variant was resisted successfully. ]

     - Enhance futex self-tests

 - Lockdep:

     - Fix dependency path printouts

     - Optimize trace saving

     - Broaden & fix wait-context checks

 - Misc cleanups and fixes.

* tag 'locking-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
  locking/lockdep: Correct the description error for check_redundant()
  futex: Provide FUTEX_LOCK_PI2 to support clock selection
  futex: Prepare futex_lock_pi() for runtime clock selection
  lockdep/selftest: Remove wait-type RCU_CALLBACK tests
  lockdep/selftests: Fix selftests vs PROVE_RAW_LOCK_NESTING
  lockdep: Fix wait-type for empty stack
  locking/selftests: Add a selftest for check_irq_usage()
  lockding/lockdep: Avoid to find wrong lock dep path in check_irq_usage()
  locking/lockdep: Remove the unnecessary trace saving
  locking/lockdep: Fix the dep path printing for backwards BFS
  selftests: futex: Add futex compare requeue test
  selftests: futex: Add futex wait test
  seqlock: Remove trailing semicolon in macros
  locking/lockdep: Reduce LOCKDEP dependency list
  locking/lockdep,doc: Improve readability of the block matrix
  locking/atomics: atomic-instrumented: simplify ifdeffery
  locking/atomic: delete !ARCH_ATOMIC remnants
  locking/atomic: xtensa: move to ARCH_ATOMIC
  locking/atomic: sparc: move to ARCH_ATOMIC
  locking/atomic: sh: move to ARCH_ATOMIC
  ...