Re: [PATCH 3/6] hisi_sas: use slot abort in v1 hw

[Hannes Reinecke]

On 02/16/2016 01:22 PM, John Garry wrote:
> When TRANS_TX_CREDIT_TIMEOUT_ERR or
> TRANS_TX_CLOSE_NORMAL_ERR errors occur for a
> command, the command should be re-attempted.
> 
> Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
> ---
>  drivers/scsi/hisi_sas/hisi_sas_v1_hw.c | 22 ++++++++++++++++++----
>  1 file changed, 18 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c
> index ce5f65d..34f71a1c 100644
> --- a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c
> +++ b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c
> @@ -1118,9 +1118,8 @@ static int prep_ssp_v1_hw(struct hisi_hba *hisi_hba,
>  }
>  
>  /* by default, task resp is complete */
> -static void slot_err_v1_hw(struct hisi_hba *hisi_hba,
> -			   struct sas_task *task,
> -			   struct hisi_sas_slot *slot)
> +static void slot_err_v1_hw(struct hisi_hba *hisi_hba, struct sas_task *task,
> +			   struct hisi_sas_slot *slot, int *abort_slot)
>  {
>  	struct task_status_struct *ts = &task->task_status;
>  	struct hisi_sas_err_record_v1 *err_record = slot->status_buffer;
> @@ -1212,6 +1211,14 @@ static void slot_err_v1_hw(struct hisi_hba *hisi_hba,
>  			ts->stat = SAS_NAK_R_ERR;
>  			break;
>  		}
> +		case TRANS_TX_CREDIT_TIMEOUT_ERR:
> +		case TRANS_TX_CLOSE_NORMAL_ERR:
> +		{
> +			/* This will request a retry */
> +			ts->stat = SAS_QUEUE_FULL;
> +			++(*abort_slot);
> +			break;
> +		}
>  		default:
>  		{
>  			ts->stat = SAM_STAT_CHECK_CONDITION;
> @@ -1317,8 +1324,14 @@ static int slot_complete_v1_hw(struct hisi_hba *hisi_hba,
>  
>  	if (cmplt_hdr_data & CMPLT_HDR_ERR_RCRD_XFRD_MSK &&
>  		!(cmplt_hdr_data & CMPLT_HDR_RSPNS_XFRD_MSK)) {
> +		int abort_slot = 0;
>  
> -		slot_err_v1_hw(hisi_hba, task, slot);
> +		slot_err_v1_hw(hisi_hba, task, slot,  &abort_slot);
> +		if (unlikely(abort_slot)) {
> +			queue_work(hisi_hba->wq, &slot->abort_slot);
> +			sts = ts->stat;
> +			goto out_1;
> +		}
>  		goto out;
>  	}
>  
What is the 'abort_slot' variable for?
Currently it's just a counter, no?
So why the weird pointer passing?

And it does feel weird. Apparently the driver does get a message,
but still has to abort the command. Why?
Isn't the message an indicator that the command has been aborted?

Cheers,

Hannes

-- 
Dr. Hannes Reinecke		   Teamlead Storage & Networking
hare@xxxxxxx			               +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg
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