[PATCH] scsi: iscsi: register sysfs for workqueue iscsi_destroy

[Bob Liu <bob.liu@oracle.com>]

Register sysfs for workqueue iscsi_destroy, so that users can set cpu affinity
through "cpumask" for this workqueue to get better isolation in cloud
multi-tenant scenario.

This patch unfolded create_singlethread_workqueue(), added WQ_SYSFS and drop
__WQ_ORDERED_EXPLICIT since __WQ_ORDERED_EXPLICIT workqueue isn't allowed to
change "cpumask".

Suggested-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Bob Liu <bob.liu@oracle.com>
---
 drivers/scsi/scsi_transport_iscsi.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 7ae5024..aa8d4a3 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -4766,7 +4766,9 @@ static __init int iscsi_transport_init(void)
 		goto release_nls;
 	}
 
-	iscsi_destroy_workq = create_singlethread_workqueue("iscsi_destroy");
+	iscsi_destroy_workq = alloc_workqueue("%s",
+			WQ_SYSFS | __WQ_LEGACY | WQ_MEM_RECLAIM | WQ_UNBOUND,
+			1, "iscsi_destroy");
 	if (!iscsi_destroy_workq) {
 		err = -ENOMEM;
 		goto destroy_wq;
-- 
2.9.5