[PATCH v2 4/8] nvme-pci: quiesce/unquiesce admin_q instead of start/stop its hw queues

[Sagi Grimberg]

unlike blk_mq_stop_hw_queues and blk_mq_start_stopped_hw_queues
quiescing/unquiescing respects the submission path rcu grace.

Signed-off-by: Sagi Grimberg <sagi at grimberg.me>
---
 drivers/nvme/host/pci.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index eb729ff70e7d..df7c8a355075 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1125,7 +1125,7 @@ static int nvme_suspend_queue(struct nvme_queue *nvmeq)
 	spin_unlock_irq(&nvmeq->q_lock);
 
 	if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q)
-		blk_mq_stop_hw_queues(nvmeq->dev->ctrl.admin_q);
+		blk_mq_quiesce_queue(nvmeq->dev->ctrl.admin_q);
 
 	pci_free_irq(to_pci_dev(nvmeq->dev->dev), vector, nvmeq);
 
@@ -1315,7 +1315,7 @@ static void nvme_dev_remove_admin(struct nvme_dev *dev)
 		 * user requests may be waiting on a stopped queue. Start the
 		 * queue to flush these to completion.
 		 */
-		blk_mq_start_stopped_hw_queues(dev->ctrl.admin_q, true);
+		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
 		blk_cleanup_queue(dev->ctrl.admin_q);
 		blk_mq_free_tag_set(&dev->admin_tagset);
 	}
@@ -1351,8 +1351,10 @@ static int nvme_alloc_admin_tags(struct nvme_dev *dev)
 			dev->ctrl.admin_q = NULL;
 			return -ENODEV;
 		}
-	} else
-		blk_mq_start_stopped_hw_queues(dev->ctrl.admin_q, true);
+	} else {
+		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
+		blk_mq_kick_requeue_list(dev->ctrl.admin_q);
+	}
 
 	return 0;
 }
-- 
2.7.4