Re: [PATCH V2] scsi: core: use blk_mq_requeue_request in __scsi_queue_insert

Martin K. Petersen
2018-03-02T01:44:22Z

Jianchao,

> In scsi core, __scsi_queue_insert should just put request back on the
> queue and retry using the same command as before. However, for blk-mq,
> scsi_mq_requeue_cmd is employed here which will unprepare the
> request. To align with the semantics of __scsi_queue_insert, use
> blk_mq_requeue_request with kick_requeue_list == true and put the
> reference of scsi_device.
>
> V1 -> V2:
> - add put_device on scsi_device->sdev_gendev

Also, please put changelog after the --- delimiter.

> Cc: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
> ---
> drivers/scsi/scsi_lib.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
> index a86df9c..6fa7b0c 100644
> --- a/drivers/scsi/scsi_lib.c
> +++ b/drivers/scsi/scsi_lib.c
> @@ -191,7 +191,8 @@ static void __scsi_queue_insert(struct scsi_cmnd *cmd, int reason, bool unbusy)
> */
> cmd->result = 0;
> if (q->mq_ops) {
> - scsi_mq_requeue_cmd(cmd);
> + blk_mq_requeue_request(cmd->request, true);
> + put_device(&device->sdev_gendev);
> return;
> }
> spin_lock_irqsave(q->queue_lock, flags);

--
Martin K. Petersen Oracle Linux Engineering