tools/memory-model/Documentation/cheatsheet.txt

   1                                   Prior Operation     Subsequent Operation
   2                                   ---------------  ---------------------------
   3                                C  Self  R  W  RMW  Self  R  W  DR  DW  RMW  SV
   4                               --  ----  -  -  ---  ----  -  -  --  --  ---  --
   5
   6 Store, e.g., WRITE_ONCE()            Y                                       Y
   7 Load, e.g., READ_ONCE()              Y                          Y   Y        Y
   8 Unsuccessful RMW operation           Y                          Y   Y        Y
   9 rcu_dereference()                    Y                          Y   Y        Y
  10 Successful *_acquire()               R                   Y  Y   Y   Y    Y   Y
  11 Successful *_release()         C        Y  Y    Y     W                      Y
  12 smp_rmb()                               Y       R        Y      Y        R
  13 smp_wmb()                                  Y    W           Y       Y    W
  14 smp_mb() & synchronize_rcu()  CP        Y  Y    Y        Y  Y   Y   Y    Y
  15 Successful full non-void RMW  CP     Y  Y  Y    Y     Y  Y  Y   Y   Y    Y   Y
  16 smp_mb__before_atomic()       CP        Y  Y    Y        a  a   a   a    Y
  17 smp_mb__after_atomic()        CP        a  a    Y        Y  Y   Y   Y    Y
  18
  19
  20 Key:    C:      Ordering is cumulative
  21         P:      Ordering propagates
  22         R:      Read, for example, READ_ONCE(), or read portion of RMW
  23         W:      Write, for example, WRITE_ONCE(), or write portion of RMW
  24         Y:      Provides ordering
  25         a:      Provides ordering given intervening RMW atomic operation
  26         DR:     Dependent read (address dependency)
  27         DW:     Dependent write (address, data, or control dependency)
  28         RMW:    Atomic read-modify-write operation
  29         SELF:   Orders self, as opposed to accesses before and/or after
  30         SV:     Orders later accesses to the same variable