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    Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · ca520cab
    Linus Torvalds authored
    Pull locking and atomic updates from Ingo Molnar:
     "Main changes in this cycle are:
    
       - Extend atomic primitives with coherent logic op primitives
         (atomic_{or,and,xor}()) and deprecate the old partial APIs
         (atomic_{set,clear}_mask())
    
         The old ops were incoherent with incompatible signatures across
         architectures and with incomplete support.  Now every architecture
         supports the primitives consistently (by Peter Zijlstra)
    
       - Generic support for 'relaxed atomics':
    
           - _acquire/release/relaxed() flavours of xchg(), cmpxchg() and {add,sub}_return()
           - atomic_read_acquire()
           - atomic_set_release()
    
         This came out of porting qwrlock code to arm64 (by Will Deacon)
    
       - Clean up the fragile static_key APIs that were causing repeat bugs,
         by introducing a new one:
    
           DEFINE_STATIC_KEY_TRUE(name);
           DEFINE_STATIC_KEY_FALSE(name);
    
         which define a key of different types with an initial true/false
         value.
    
         Then allow:
    
           static_branch_likely()
           static_branch_unlikely()
    
         to take a key of either type and emit the right instruction for the
         case.  To be able to know the 'type' of the static key we encode it
         in the jump entry (by Peter Zijlstra)
    
       - Static key self-tests (by Jason Baron)
    
       - qrwlock optimizations (by Waiman Long)
    
       - small futex enhancements (by Davidlohr Bueso)
    
       - ... and misc other changes"
    
    * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits)
      jump_label/x86: Work around asm build bug on older/backported GCCs
      locking, ARM, atomics: Define our SMP atomics in terms of _relaxed() operations
      locking, include/llist: Use linux/atomic.h instead of asm/cmpxchg.h
      locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics
      locking/qrwlock: Implement queue_write_unlock() using smp_store_release()
      locking/lockref: Remove homebrew cmpxchg64_relaxed() macro definition
      locking, asm-generic: Add _{relaxed|acquire|release}() variants for 'atomic_long_t'
      locking, asm-generic: Rework atomic-long.h to avoid bulk code duplication
      locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
      locking, compiler.h: Cast away attributes in the WRITE_ONCE() magic
      locking/static_keys: Make verify_keys() static
      jump label, locking/static_keys: Update docs
      locking/static_keys: Provide a selftest
      jump_label: Provide a self-test
      s390/uaccess, locking/static_keys: employ static_branch_likely()
      x86, tsc, locking/static_keys: Employ static_branch_likely()
      locking/static_keys: Add selftest
      locking/static_keys: Add a new static_key interface
      locking/static_keys: Rework update logic
      locking/static_keys: Add static_key_{en,dis}able() helpers
      ...
    ca520cab