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Subject[PATCH tip/core/rcu 5/5] documentation: memory-barriers.txt: Correct example for reorderings
Date
From: Pranith Kumar <bobby.prani@gmail.com>

Correct the example of memory orderings in memory-barriers.txt

Commit 615cc2c9cf95 "Documentation/memory-barriers.txt: fix important typo re
memory barriers" changed the assignment to x and y. Change the rest of the
example to match this change.

Reported-by: Ganesh Rapolu <ganesh.rapolu@hotmail.com>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
Documentation/memory-barriers.txt | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index 8ebb66128cc8..3d5f49b9f82b 100644
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -121,22 +121,22 @@ For example, consider the following sequence of events:
The set of accesses as seen by the memory system in the middle can be arranged
in 24 different combinations:

- STORE A=3, STORE B=4, x=LOAD A->3, y=LOAD B->4
- STORE A=3, STORE B=4, y=LOAD B->4, x=LOAD A->3
- STORE A=3, x=LOAD A->3, STORE B=4, y=LOAD B->4
- STORE A=3, x=LOAD A->3, y=LOAD B->2, STORE B=4
- STORE A=3, y=LOAD B->2, STORE B=4, x=LOAD A->3
- STORE A=3, y=LOAD B->2, x=LOAD A->3, STORE B=4
- STORE B=4, STORE A=3, x=LOAD A->3, y=LOAD B->4
+ STORE A=3, STORE B=4, y=LOAD A->3, x=LOAD B->4
+ STORE A=3, STORE B=4, x=LOAD B->4, y=LOAD A->3
+ STORE A=3, y=LOAD A->3, STORE B=4, x=LOAD B->4
+ STORE A=3, y=LOAD A->3, x=LOAD B->2, STORE B=4
+ STORE A=3, x=LOAD B->2, STORE B=4, y=LOAD A->3
+ STORE A=3, x=LOAD B->2, y=LOAD A->3, STORE B=4
+ STORE B=4, STORE A=3, y=LOAD A->3, x=LOAD B->4
STORE B=4, ...
...

and can thus result in four different combinations of values:

- x == 1, y == 2
- x == 1, y == 4
- x == 3, y == 2
- x == 3, y == 4
+ x == 2, y == 1
+ x == 2, y == 3
+ x == 4, y == 1
+ x == 4, y == 3


Furthermore, the stores committed by a CPU to the memory system may not be
--
1.8.1.5


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