============
  LITMUS TESTS
  ============

  Each subdirectory contains litmus tests that are typical to describe the
  semantics of respective kernel APIs.
  For more information about how to "run" a litmus test or how to generate
  a kernel test module based on a litmus test, please see
  tools/memory-model/README.
  
  
  atomic (/atomic derectory)
  --------------------------
  
  Atomic-RMW+mb__after_atomic-is-stronger-than-acquire.litmus
      Test that an atomic RMW followed by a smp_mb__after_atomic() is
      stronger than a normal acquire: both the read and write parts of
      the RMW are ordered before the subsequential memory accesses.
  
  Atomic-RMW-ops-are-atomic-WRT-atomic_set.litmus
      Test that atomic_set() cannot break the atomicity of atomic RMWs.

      NOTE: Require herd7 7.56 or later which supports "(void)expr".

  RCU (/rcu directory)
  --------------------

  MP+onceassign+derefonce.litmus (under tools/memory-model/litmus-tests/)
      Demonstrates the use of rcu_assign_pointer() and rcu_dereference() to
      ensure that an RCU reader will not see pre-initialization garbage.

  RCU+sync+read.litmus
  RCU+sync+free.litmus
      Both the above litmus tests demonstrate the RCU grace period guarantee
      that an RCU read-side critical section can never span a grace period.