[PATCH] Documentation,barriers: Mention smp_cond_acquire()

[Davidlohr Bueso <dave@stgolabs.net>]

... do this next to smp_load_acquire when first mentioning
ACQUIRE. While this call is briefly explained and ctrl
dependencies are mentioned later, it does not hurt the reader.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
 Documentation/memory-barriers.txt | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index 3729cbe60e41..2b5ea9d01a8f 100644
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -430,8 +430,9 @@ And a couple of implicit varieties:
      This acts as a one-way permeable barrier.  It guarantees that all memory
      operations after the ACQUIRE operation will appear to happen after the
      ACQUIRE operation with respect to the other components of the system.
-     ACQUIRE operations include LOCK operations and smp_load_acquire()
-     operations.
+     ACQUIRE operations include LOCK operations and both smp_load_acquire()
+     and smp_cond_acquire() operations. The later builds the necessary ACQUIRE
+     semantics from relying on a control dependency and smp_rmb().
 
      Memory operations that occur before an ACQUIRE operation may appear to
      happen after it completes.
-- 
2.1.4