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From:   Jinlong Chen <nickyc975@zju.edu.cn>
To:     axboe@kernel.dk
Cc:     hch@lst.de, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, nickyc975@zju.edu.cn
Subject: [PATCH 1/4] blk-mq: update comment for blk_mq_quiesce_queue_nowait()
Date:   Tue,  1 Nov 2022 23:11:34 +0800
Message-Id: <489a9322eed1f95f8770752cc715084f1fa961d3.1667314759.git.nickyc975@zju.edu.cn>
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blk_mq_quiesce_queue_nowait() is now reasonably used by scsi_host_block()
to avoid calling synchronize_rcu() for each LUN. We should not consider to
remove it.

See commit f983622ae60516d634008c7b1ff9ffff4f7bb8ae ("scsi: core: Avoid
calling synchronize_rcu() for each device in scsi_host_block()")

Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn>
---
 block/blk-mq.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 623e8a506539..7ceceea91b3b 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -237,9 +237,12 @@ void blk_mq_unfreeze_queue(struct request_queue *q)
 }
 EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue);
 
-/*
- * FIXME: replace the scsi_internal_device_*block_nowait() calls in the
- * mpt3sas driver such that this function can be removed.
+/**
+ * blk_mq_quiesce_queue_nowait() - start the quiesce of the queue
+ * @q: request queue.
+ *
+ * Note: synchronize_rcu() or synchronize_srcu(q->srcu) needs to
+ * be called to ensure the quiesce is done.
  */
 void blk_mq_quiesce_queue_nowait(struct request_queue *q)
 {
-- 
2.31.1