hc
2024-05-10 37f49e37ab4cb5d0bc4c60eb5c6d4dd57db767bb
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                                  Prior Operation     Subsequent Operation
                                  ---------------  ---------------------------
                               C  Self  R  W  RMW  Self  R  W  DR  DW  RMW  SV
                              --  ----  -  -  ---  ----  -  -  --  --  ---  --
 
Relaxed store                        Y                                       Y
Relaxed load                         Y                          Y   Y        Y
Relaxed RMW operation                Y                          Y   Y        Y
rcu_dereference()                    Y                          Y   Y        Y
Successful *_acquire()               R                   Y  Y   Y   Y    Y   Y
Successful *_release()         C        Y  Y    Y     W                      Y
smp_rmb()                               Y       R        Y      Y        R
smp_wmb()                                  Y    W           Y       Y    W
smp_mb() & synchronize_rcu()  CP        Y  Y    Y        Y  Y   Y   Y    Y
Successful full non-void RMW  CP     Y  Y  Y    Y     Y  Y  Y   Y   Y    Y   Y
smp_mb__before_atomic()       CP        Y  Y    Y        a  a   a   a    Y
smp_mb__after_atomic()        CP        a  a    Y        Y  Y   Y   Y    Y
 
 
Key:    Relaxed:  A relaxed operation is either READ_ONCE(), WRITE_ONCE(),
         a *_relaxed() RMW operation, an unsuccessful RMW
         operation, a non-value-returning RMW operation such
         as atomic_inc(), or one of the atomic*_read() and
         atomic*_set() family of operations.
   C:      Ordering is cumulative
   P:      Ordering propagates
   R:      Read, for example, READ_ONCE(), or read portion of RMW
   W:      Write, for example, WRITE_ONCE(), or write portion of RMW
   Y:      Provides ordering
   a:      Provides ordering given intervening RMW atomic operation
   DR:      Dependent read (address dependency)
   DW:      Dependent write (address, data, or control dependency)
   RMW:      Atomic read-modify-write operation
   SELF:      Orders self, as opposed to accesses before and/or after
   SV:      Orders later accesses to the same variable