[PATCH] workqueue: doc change for ST behavior on NUMA systems

[Alexei Potashnik <alexei@purestorage.com>]

NUMA rework of workqueue made the combination of max_active of 1 and
WQ_UNBOUND insufficient to guarantee ST behavior system wide.

alloc_ordered_queue should now be used instead.

Signed-off-by: Alexei Potashnik <alexei@purestorage.com>
---
 Documentation/core-api/workqueue.rst | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/Documentation/core-api/workqueue.rst
b/Documentation/core-api/workqueue.rst
index ffdec94..3943b5b 100644
--- a/Documentation/core-api/workqueue.rst
+++ b/Documentation/core-api/workqueue.rst
@@ -243,11 +243,15 @@ throttling the number of active work items,
specifying '0' is
 recommended.

 Some users depend on the strict execution ordering of ST wq.  The
-combination of ``@max_active`` of 1 and ``WQ_UNBOUND`` is used to
-achieve this behavior.  Work items on such wq are always queued to the
-unbound worker-pools and only one work item can be active at any given
+combination of ``@max_active`` of 1 and ``WQ_UNBOUND`` used to
+achieve this behavior.  Work items on such wq were always queued to the
+unbound worker-pools and only one work item could be active at any given
 time thus achieving the same ordering property as ST wq.

+In the current implementation the above configuration only guarantees
+ST behavior within a given NUMA node. Instead alloc_ordered_queue should
+be used to achieve system wide ST behavior.
+

 Example Execution Scenarios
 ===========================
-- 
1.9.1