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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
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parentInitial commit. (diff)
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Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+ Prior Operation Subsequent Operation
+ --------------- ---------------------------
+ C Self R W RMW Self R W DR DW RMW SV
+ -- ---- - - --- ---- - - -- -- --- --
+
+Store, e.g., WRITE_ONCE() Y Y
+Load, e.g., READ_ONCE() Y Y Y Y
+Unsuccessful 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: 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