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authorPaul E. McKenney <paulmck@kernel.org>2020-08-04 21:35:56 +0300
committerPaul E. McKenney <paulmck@kernel.org>2020-09-04 21:58:15 +0300
commit0ce0c78eff7d22c8a261de6c4305a5abb638c200 (patch)
tree8df479d049eb00c38072ce48f67faae5d9cf9f18 /tools/memory-model
parent0b8c06b75ea143f3c68aa419c36e82d9ab7454f8 (diff)
downloadlinux-0ce0c78eff7d22c8a261de6c4305a5abb638c200.tar.xz
tools/memory-model: Expand the cheatsheet.txt notion of relaxed
This commit adds a key entry enumerating the various types of relaxed operations. While in the area, it also renames the relaxed rows. [ paulmck: Apply Boqun Feng feedback. ] Acked-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'tools/memory-model')
-rw-r--r--tools/memory-model/Documentation/cheatsheet.txt33
1 files changed, 19 insertions, 14 deletions
diff --git a/tools/memory-model/Documentation/cheatsheet.txt b/tools/memory-model/Documentation/cheatsheet.txt
index 33ba98d72b16..99d00870b160 100644
--- a/tools/memory-model/Documentation/cheatsheet.txt
+++ b/tools/memory-model/Documentation/cheatsheet.txt
@@ -3,9 +3,9 @@
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
+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
@@ -17,14 +17,19 @@ 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
+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