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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
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