locking-core-2021-06-28

 - 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.

Signed-off-by: Ingo Molnar <mingo@kernel.org>