Re: [PATCH] scsi: ufs: core: quiesce request queues before check pending cmds

[Bart Van Assche]

On 6/7/24 04:06, Ziqi Chen wrote:
> diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
> index 21429ee..1afa862 100644
> --- a/drivers/ufs/core/ufshcd.c
> +++ b/drivers/ufs/core/ufshcd.c
> @@ -1392,7 +1392,7 @@ static int ufshcd_clock_scaling_prepare(struct ufs_hba *hba, u64 timeout_us)
>   	 * make sure that there are no outstanding requests when
>   	 * clock scaling is in progress
>   	 */
> -	ufshcd_scsi_block_requests(hba);
> +	blk_mq_quiesce_tagset(&hba->host->tag_set);
>   	mutex_lock(&hba->wb_mutex);
>   	down_write(&hba->clk_scaling_lock);
>   
> @@ -1401,7 +1401,7 @@ static int ufshcd_clock_scaling_prepare(struct ufs_hba *hba, u64 timeout_us)
>   		ret = -EBUSY;
>   		up_write(&hba->clk_scaling_lock);
>   		mutex_unlock(&hba->wb_mutex);
> -		ufshcd_scsi_unblock_requests(hba);
> +		blk_mq_unquiesce_tagset(&hba->host->tag_set);
>   		goto out;
>   	}
>   
> @@ -1422,7 +1422,7 @@ static void ufshcd_clock_scaling_unprepare(struct ufs_hba *hba, int err, bool sc
>   
>   	mutex_unlock(&hba->wb_mutex);
>   
> -	ufshcd_scsi_unblock_requests(hba);
> +	blk_mq_unquiesce_tagset(&hba->host->tag_set);
>   	ufshcd_release(hba);
>   }

Why to replace only those ufshcd_scsi_block_requests() /
ufshcd_scsi_unblock_requests() calls? I don't think that it is ever safe to
use these functions instead of  blk_mq_quiesce_tagset() /
blk_mq_unquiesce_tagset(). Please replace all ufshcd_scsi_block_requests() /
ufshcd_scsi_unblock_requests() calls and remove the
ufshcd_scsi_*block_requests() functions.

Thanks,

Bart.