From: Keith Busch <keith.busch@intel.com>
Date: Wed, 6 Jun 2018 08:13:04 -0600
Subject: [PATCH] nvme-pci: remove unnecessary nested locking
Git-commit: 0bc88192033a6e652e3fb1adfd6d1b66be33951e
Patch-mainline: v4.18-rc1
References: bsc#1104967,FATE#325924

The nvme pci driver no longer handles completions under the cq lock,
so the nested locking is not necessary.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Hannes Reinecke <hare@suse.com>
---
 drivers/nvme/host/pci.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index e526437bacbf..a7bed8dccd61 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2012,13 +2012,7 @@ static void nvme_del_cq_end(struct request *req, blk_status_t error)
 	if (!error) {
 		unsigned long flags;
 
-		/*
-		 * We might be called with the AQ cq_lock held
-		 * and the I/O queue cq_lock should always
-		 * nest inside the AQ one.
-		 */
-		spin_lock_irqsave_nested(&nvmeq->cq_lock, flags,
-					SINGLE_DEPTH_NESTING);
+		spin_lock_irqsave(&nvmeq->cq_lock, flags);
 		nvme_process_cq(nvmeq, &start, &end, -1);
 		spin_unlock_irqrestore(&nvmeq->cq_lock, flags);
 
-- 
2.16.4