dm: convert workqueues to alloc_ordered

Convert all create[_singlethread]_work() users to the new
alloc[_ordered]_workqueue().  This conversion is mechanical and
doesn't introduce any behavior change.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

drivers/md/dm-mpath.c

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index fcc59c3..35ab578 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1675,7 +1675,7 @@
 		return -EINVAL;
 	}
 
-	kmultipathd = create_workqueue("kmpathd");
+	kmultipathd = alloc_workqueue("kmpathd", WQ_MEM_RECLAIM, 0);
 	if (!kmultipathd) {
 		DMERR("failed to create workqueue kmpathd");
 		dm_unregister_target(&multipath_target);
@@ -1689,7 +1689,8 @@
 	 * old workqueue would also create a bottleneck in the
 	 * path of the storage hardware device activation.
 	 */
-	kmpath_handlerd = create_singlethread_workqueue("kmpath_handlerd");
+	kmpath_handlerd = alloc_ordered_workqueue("kmpath_handlerd",
+						  WQ_MEM_RECLAIM);
 	if (!kmpath_handlerd) {
 		DMERR("failed to create workqueue kmpath_handlerd");
 		destroy_workqueue(kmultipathd);