Re: [PATCH 08/11] scsi: always assign block layer tags if enabled

[Bart Van Assche <bvanassche@acm.org>]

On 11/04/14 08:54, Christoph Hellwig wrote:
> -/**
> - * scsi_activate_tcq - turn on tag command queueing
> - * @SDpnt:	device to turn on TCQ for
> - * @depth:	queue depth
> - *
> - * Notes:
> - *	Eventually, I hope depth would be the maximum depth
> - *	the device could cope with and the real queue depth
> - *	would be adjustable from 0 to depth.
> - **/
> -static inline void scsi_activate_tcq(struct scsi_device *sdev, int depth)
> -{
> -	if (!sdev->tagged_supported)
> -		return;
> -
> -	if (shost_use_blk_mq(sdev->host))
> -		queue_flag_set_unlocked(QUEUE_FLAG_QUEUED, sdev->request_queue);
> -	else if (!blk_queue_tagged(sdev->request_queue))
> -		blk_queue_init_tags(sdev->request_queue, depth,
> -				    sdev->host->bqt);
> -
> -	scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
> -}

Apparently this patch removes the 
queue_flag_set_unlocked(QUEUE_FLAG_QUEUED, sdev->request_queue) call for 
the multiqueue case. I think it should be explained in the commit 
message why that has been done.

> -/**
> - * scsi_deactivate_tcq - turn off tag command queueing
> - * @SDpnt:	device to turn off TCQ for
> - **/
> -static inline void scsi_deactivate_tcq(struct scsi_device *sdev, int depth)
> -{
> -	if (blk_queue_tagged(sdev->request_queue))
> -		blk_queue_free_tags(sdev->request_queue);
> -	scsi_adjust_queue_depth(sdev, 0, depth);
> -}

Hmm ... where has the blk_queue_free_tags() call been moved to ?

Bart.