[PATCH] doc: memory-barriers.txt: Add barrier() to provide ordering

Pranith Kumar
2014-08-11T22:52:09Z

In the provably false case, add barrier() in both the legs of the if() condition
to provide ordering.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
---
Documentation/memory-barriers.txt | 2 ++
1 file changed, 2 insertions(+)

diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index 41a6c9c..0f2903f 100644
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -689,9 +689,11 @@ should do something like the following:
q = ACCESS_ONCE(a);
BUILD_BUG_ON(MAX <= 1); /* Order load from a with store to b. */
if (q % MAX) {
+ barrier();
ACCESS_ONCE(b) = p;
do_something();
} else {
+ barrier();
ACCESS_ONCE(b) = p;
do_something_else();
}
--
1.9.1