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

Signed-off-by: Pranith Kumar <bobby.pr...@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

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