[v2] ata:libata-eh:Cleanup ata_scsi_cmd_error_handler

Message ID 20221215105747.1927412-1-haowenchao@huawei.com
State New
Headers
Series [v2] ata:libata-eh:Cleanup ata_scsi_cmd_error_handler |

Commit Message

Wenchao Hao Dec. 15, 2022, 10:57 a.m. UTC
  If ap->ops->error_handler is NULL, just return.

V2:
- Check ap->ops->error_handler without taking the spin lock

Signed-off-by: Wenchao Hao <haowenchao@huawei.com>
---
 drivers/ata/libata-eh.c | 96 ++++++++++++++++++++---------------------
 1 file changed, 48 insertions(+), 48 deletions(-)
  

Comments

Sergei Shtylyov Dec. 15, 2022, 11:30 a.m. UTC | #1
Hello!

  The subject should really look like "ata: libata-eh: Cleanup
ata_scsi_cmd_error_handler()"...

On 12/15/22 1:57 PM, Wenchao Hao wrote:

> If ap->ops->error_handler is NULL, just return.
> 
> V2:
> - Check ap->ops->error_handler without taking the spin lock

   This normally belongs under ---...

> Signed-off-by: Wenchao Hao <haowenchao@huawei.com>
> ---
>  drivers/ata/libata-eh.c | 96 ++++++++++++++++++++---------------------
>  1 file changed, 48 insertions(+), 48 deletions(-)
> 
> diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
> index 34303ce67c14..c445c272e77f 100644
> --- a/drivers/ata/libata-eh.c
> +++ b/drivers/ata/libata-eh.c
[...]
> @@ -584,62 +589,57 @@ void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
>  	 * timed out iff its associated qc is active and not failed.
>  	 */
>  	spin_lock_irqsave(ap->lock, flags);
> -	if (ap->ops->error_handler) {
> -		struct scsi_cmnd *scmd, *tmp;
> -		int nr_timedout = 0;
> -
> -		/* This must occur under the ap->lock as we don't want
> -		   a polled recovery to race the real interrupt handler
> -
> -		   The lost_interrupt handler checks for any completed but
> -		   non-notified command and completes much like an IRQ handler.
>  
> -		   We then fall into the error recovery code which will treat
> -		   this as if normal completion won the race */
> -
> -		if (ap->ops->lost_interrupt)
> -			ap->ops->lost_interrupt(ap);
> +	/* This must occur under the ap->lock as we don't want

   The multi-line comments should start with /* on its own line...

> +	 * a polled recovery to race the real interrupt handler
> +	 *
> +	 * The lost_interrupt handler checks for any completed but
> +	 * non-notified command and completes much like an IRQ handler.
> +	 *
> +	 * We then fall into the error recovery code which will treat
> +	 * this as if normal completion won the race
> +	 */
> +	if (ap->ops->lost_interrupt)
> +		ap->ops->lost_interrupt(ap);
>  
> -		list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
> -			struct ata_queued_cmd *qc;
> +	list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
> +		struct ata_queued_cmd *qc;
>  
> -			ata_qc_for_each_raw(ap, qc, i) {
> -				if (qc->flags & ATA_QCFLAG_ACTIVE &&
> -				    qc->scsicmd == scmd)
> -					break;
> -			}
> +		ata_qc_for_each_raw(ap, qc, i) {
> +			if (qc->flags & ATA_QCFLAG_ACTIVE &&
> +			    qc->scsicmd == scmd)
> +				break;
> +		}
>  
> -			if (i < ATA_MAX_QUEUE) {
> -				/* the scmd has an associated qc */
> -				if (!(qc->flags & ATA_QCFLAG_FAILED)) {
> -					/* which hasn't failed yet, timeout */
> -					qc->err_mask |= AC_ERR_TIMEOUT;
> -					qc->flags |= ATA_QCFLAG_FAILED;
> -					nr_timedout++;
> -				}
> -			} else {
> -				/* Normal completion occurred after
> -				 * SCSI timeout but before this point.
> -				 * Successfully complete it.
> -				 */
> -				scmd->retries = scmd->allowed;
> -				scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
> +		if (i < ATA_MAX_QUEUE) {
> +			/* the scmd has an associated qc */
> +			if (!(qc->flags & ATA_QCFLAG_FAILED)) {
> +				/* which hasn't failed yet, timeout */
> +				qc->err_mask |= AC_ERR_TIMEOUT;
> +				qc->flags |= ATA_QCFLAG_FAILED;
> +				nr_timedout++;
>  			}
> +		} else {
> +			/* Normal completion occurred after

   Here as well...

> +			 * SCSI timeout but before this point.
> +			 * Successfully complete it.
> +			 */
> +			scmd->retries = scmd->allowed;
> +			scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
>  		}
> +	}
>  
> -		/* If we have timed out qcs.  They belong to EH from
> -		 * this point but the state of the controller is
> -		 * unknown.  Freeze the port to make sure the IRQ
> -		 * handler doesn't diddle with those qcs.  This must
> -		 * be done atomically w.r.t. setting QCFLAG_FAILED.
> -		 */
> -		if (nr_timedout)
> -			__ata_port_freeze(ap);
> -
> +	/* If we have timed out qcs.  They belong to EH from

   And here...

[...]

MBR, Sergey
  
Damien Le Moal Dec. 15, 2022, 11:33 a.m. UTC | #2
On 12/15/22 19:57, Wenchao Hao wrote:
> If ap->ops->error_handler is NULL, just return.
> 
> V2:
> - Check ap->ops->error_handler without taking the spin lock

Changelog needs to go after the "---" below your SoB.

> 
> Signed-off-by: Wenchao Hao <haowenchao@huawei.com>
> ---
>  drivers/ata/libata-eh.c | 96 ++++++++++++++++++++---------------------
>  1 file changed, 48 insertions(+), 48 deletions(-)
> 
> diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
> index 34303ce67c14..c445c272e77f 100644
> --- a/drivers/ata/libata-eh.c
> +++ b/drivers/ata/libata-eh.c
> @@ -565,10 +565,15 @@ void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
>  {
>  	int i;
>  	unsigned long flags;
> +	struct scsi_cmnd *scmd, *tmp;
> +	int nr_timedout = 0;
>  
>  	/* make sure sff pio task is not running */
>  	ata_sff_flush_pio_task(ap);
>  
> +	if (!ap->ops->error_handler)
> +		return;
> +
>  	/* synchronize with host lock and sort out timeouts */
>  
>  	/* For new EH, all qcs are finished in one of three ways -
> @@ -584,62 +589,57 @@ void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
>  	 * timed out iff its associated qc is active and not failed.
>  	 */
>  	spin_lock_irqsave(ap->lock, flags);
> -	if (ap->ops->error_handler) {
> -		struct scsi_cmnd *scmd, *tmp;
> -		int nr_timedout = 0;
> -
> -		/* This must occur under the ap->lock as we don't want
> -		   a polled recovery to race the real interrupt handler
> -
> -		   The lost_interrupt handler checks for any completed but
> -		   non-notified command and completes much like an IRQ handler.
>  
> -		   We then fall into the error recovery code which will treat
> -		   this as if normal completion won the race */
> -
> -		if (ap->ops->lost_interrupt)
> -			ap->ops->lost_interrupt(ap);
> +	/* This must occur under the ap->lock as we don't want

While at it, please fix the comment style. Multi-line comments should
start with a "/*" empty line.

> +	 * a polled recovery to race the real interrupt handler
> +	 *
> +	 * The lost_interrupt handler checks for any completed but
> +	 * non-notified command and completes much like an IRQ handler.
> +	 *
> +	 * We then fall into the error recovery code which will treat
> +	 * this as if normal completion won the race
> +	 */
> +	if (ap->ops->lost_interrupt)
> +		ap->ops->lost_interrupt(ap);
>  
> -		list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
> -			struct ata_queued_cmd *qc;
> +	list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
> +		struct ata_queued_cmd *qc;
>  
> -			ata_qc_for_each_raw(ap, qc, i) {
> -				if (qc->flags & ATA_QCFLAG_ACTIVE &&
> -				    qc->scsicmd == scmd)
> -					break;
> -			}
> +		ata_qc_for_each_raw(ap, qc, i) {
> +			if (qc->flags & ATA_QCFLAG_ACTIVE &&
> +			    qc->scsicmd == scmd)
> +				break;
> +		}
>  
> -			if (i < ATA_MAX_QUEUE) {
> -				/* the scmd has an associated qc */
> -				if (!(qc->flags & ATA_QCFLAG_FAILED)) {
> -					/* which hasn't failed yet, timeout */
> -					qc->err_mask |= AC_ERR_TIMEOUT;
> -					qc->flags |= ATA_QCFLAG_FAILED;
> -					nr_timedout++;
> -				}
> -			} else {
> -				/* Normal completion occurred after
> -				 * SCSI timeout but before this point.
> -				 * Successfully complete it.
> -				 */
> -				scmd->retries = scmd->allowed;
> -				scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
> +		if (i < ATA_MAX_QUEUE) {
> +			/* the scmd has an associated qc */
> +			if (!(qc->flags & ATA_QCFLAG_FAILED)) {
> +				/* which hasn't failed yet, timeout */
> +				qc->err_mask |= AC_ERR_TIMEOUT;
> +				qc->flags |= ATA_QCFLAG_FAILED;
> +				nr_timedout++;
>  			}
> +		} else {
> +			/* Normal completion occurred after
> +			 * SCSI timeout but before this point.
> +			 * Successfully complete it.
> +			 */
> +			scmd->retries = scmd->allowed;
> +			scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
>  		}
> +	}
>  
> -		/* If we have timed out qcs.  They belong to EH from
> -		 * this point but the state of the controller is
> -		 * unknown.  Freeze the port to make sure the IRQ
> -		 * handler doesn't diddle with those qcs.  This must
> -		 * be done atomically w.r.t. setting QCFLAG_FAILED.
> -		 */
> -		if (nr_timedout)
> -			__ata_port_freeze(ap);
> -
> +	/* If we have timed out qcs.  They belong to EH from

Same here. Fix the comment style please.

> +	 * this point but the state of the controller is
> +	 * unknown.  Freeze the port to make sure the IRQ
> +	 * handler doesn't diddle with those qcs.  This must
> +	 * be done atomically w.r.t. setting QCFLAG_FAILED.
> +	 */
> +	if (nr_timedout)
> +		__ata_port_freeze(ap);
>  
> -		/* initialize eh_tries */
> -		ap->eh_tries = ATA_EH_MAX_TRIES;
> -	}
> +	/* initialize eh_tries */
> +	ap->eh_tries = ATA_EH_MAX_TRIES;
>  	spin_unlock_irqrestore(ap->lock, flags);
>  
>  }
  
Damien Le Moal Dec. 15, 2022, 11:34 a.m. UTC | #3
On 12/15/22 20:30, Sergei Shtylyov wrote:
> Hello!
> 
>   The subject should really look like "ata: libata-eh: Cleanup
> ata_scsi_cmd_error_handler()"...
> 
> On 12/15/22 1:57 PM, Wenchao Hao wrote:
> 
>> If ap->ops->error_handler is NULL, just return.
>>
>> V2:
>> - Check ap->ops->error_handler without taking the spin lock
> 
>    This normally belongs under ---...

I should read all emails before replying. I commented exactly the same :)

> 
>> Signed-off-by: Wenchao Hao <haowenchao@huawei.com>
>> ---
>>  drivers/ata/libata-eh.c | 96 ++++++++++++++++++++---------------------
>>  1 file changed, 48 insertions(+), 48 deletions(-)
>>
>> diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
>> index 34303ce67c14..c445c272e77f 100644
>> --- a/drivers/ata/libata-eh.c
>> +++ b/drivers/ata/libata-eh.c
> [...]
>> @@ -584,62 +589,57 @@ void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
>>  	 * timed out iff its associated qc is active and not failed.
>>  	 */
>>  	spin_lock_irqsave(ap->lock, flags);
>> -	if (ap->ops->error_handler) {
>> -		struct scsi_cmnd *scmd, *tmp;
>> -		int nr_timedout = 0;
>> -
>> -		/* This must occur under the ap->lock as we don't want
>> -		   a polled recovery to race the real interrupt handler
>> -
>> -		   The lost_interrupt handler checks for any completed but
>> -		   non-notified command and completes much like an IRQ handler.
>>  
>> -		   We then fall into the error recovery code which will treat
>> -		   this as if normal completion won the race */
>> -
>> -		if (ap->ops->lost_interrupt)
>> -			ap->ops->lost_interrupt(ap);
>> +	/* This must occur under the ap->lock as we don't want
> 
>    The multi-line comments should start with /* on its own line...
> 
>> +	 * a polled recovery to race the real interrupt handler
>> +	 *
>> +	 * The lost_interrupt handler checks for any completed but
>> +	 * non-notified command and completes much like an IRQ handler.
>> +	 *
>> +	 * We then fall into the error recovery code which will treat
>> +	 * this as if normal completion won the race
>> +	 */
>> +	if (ap->ops->lost_interrupt)
>> +		ap->ops->lost_interrupt(ap);
>>  
>> -		list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
>> -			struct ata_queued_cmd *qc;
>> +	list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
>> +		struct ata_queued_cmd *qc;
>>  
>> -			ata_qc_for_each_raw(ap, qc, i) {
>> -				if (qc->flags & ATA_QCFLAG_ACTIVE &&
>> -				    qc->scsicmd == scmd)
>> -					break;
>> -			}
>> +		ata_qc_for_each_raw(ap, qc, i) {
>> +			if (qc->flags & ATA_QCFLAG_ACTIVE &&
>> +			    qc->scsicmd == scmd)
>> +				break;
>> +		}
>>  
>> -			if (i < ATA_MAX_QUEUE) {
>> -				/* the scmd has an associated qc */
>> -				if (!(qc->flags & ATA_QCFLAG_FAILED)) {
>> -					/* which hasn't failed yet, timeout */
>> -					qc->err_mask |= AC_ERR_TIMEOUT;
>> -					qc->flags |= ATA_QCFLAG_FAILED;
>> -					nr_timedout++;
>> -				}
>> -			} else {
>> -				/* Normal completion occurred after
>> -				 * SCSI timeout but before this point.
>> -				 * Successfully complete it.
>> -				 */
>> -				scmd->retries = scmd->allowed;
>> -				scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
>> +		if (i < ATA_MAX_QUEUE) {
>> +			/* the scmd has an associated qc */
>> +			if (!(qc->flags & ATA_QCFLAG_FAILED)) {
>> +				/* which hasn't failed yet, timeout */
>> +				qc->err_mask |= AC_ERR_TIMEOUT;
>> +				qc->flags |= ATA_QCFLAG_FAILED;
>> +				nr_timedout++;
>>  			}
>> +		} else {
>> +			/* Normal completion occurred after
> 
>    Here as well...
> 
>> +			 * SCSI timeout but before this point.
>> +			 * Successfully complete it.
>> +			 */
>> +			scmd->retries = scmd->allowed;
>> +			scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
>>  		}
>> +	}
>>  
>> -		/* If we have timed out qcs.  They belong to EH from
>> -		 * this point but the state of the controller is
>> -		 * unknown.  Freeze the port to make sure the IRQ
>> -		 * handler doesn't diddle with those qcs.  This must
>> -		 * be done atomically w.r.t. setting QCFLAG_FAILED.
>> -		 */
>> -		if (nr_timedout)
>> -			__ata_port_freeze(ap);
>> -
>> +	/* If we have timed out qcs.  They belong to EH from
> 
>    And here...
> 
> [...]
> 
> MBR, Sergey
  

Patch

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 34303ce67c14..c445c272e77f 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -565,10 +565,15 @@  void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
 {
 	int i;
 	unsigned long flags;
+	struct scsi_cmnd *scmd, *tmp;
+	int nr_timedout = 0;
 
 	/* make sure sff pio task is not running */
 	ata_sff_flush_pio_task(ap);
 
+	if (!ap->ops->error_handler)
+		return;
+
 	/* synchronize with host lock and sort out timeouts */
 
 	/* For new EH, all qcs are finished in one of three ways -
@@ -584,62 +589,57 @@  void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
 	 * timed out iff its associated qc is active and not failed.
 	 */
 	spin_lock_irqsave(ap->lock, flags);
-	if (ap->ops->error_handler) {
-		struct scsi_cmnd *scmd, *tmp;
-		int nr_timedout = 0;
-
-		/* This must occur under the ap->lock as we don't want
-		   a polled recovery to race the real interrupt handler
-
-		   The lost_interrupt handler checks for any completed but
-		   non-notified command and completes much like an IRQ handler.
 
-		   We then fall into the error recovery code which will treat
-		   this as if normal completion won the race */
-
-		if (ap->ops->lost_interrupt)
-			ap->ops->lost_interrupt(ap);
+	/* This must occur under the ap->lock as we don't want
+	 * a polled recovery to race the real interrupt handler
+	 *
+	 * The lost_interrupt handler checks for any completed but
+	 * non-notified command and completes much like an IRQ handler.
+	 *
+	 * We then fall into the error recovery code which will treat
+	 * this as if normal completion won the race
+	 */
+	if (ap->ops->lost_interrupt)
+		ap->ops->lost_interrupt(ap);
 
-		list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
-			struct ata_queued_cmd *qc;
+	list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
+		struct ata_queued_cmd *qc;
 
-			ata_qc_for_each_raw(ap, qc, i) {
-				if (qc->flags & ATA_QCFLAG_ACTIVE &&
-				    qc->scsicmd == scmd)
-					break;
-			}
+		ata_qc_for_each_raw(ap, qc, i) {
+			if (qc->flags & ATA_QCFLAG_ACTIVE &&
+			    qc->scsicmd == scmd)
+				break;
+		}
 
-			if (i < ATA_MAX_QUEUE) {
-				/* the scmd has an associated qc */
-				if (!(qc->flags & ATA_QCFLAG_FAILED)) {
-					/* which hasn't failed yet, timeout */
-					qc->err_mask |= AC_ERR_TIMEOUT;
-					qc->flags |= ATA_QCFLAG_FAILED;
-					nr_timedout++;
-				}
-			} else {
-				/* Normal completion occurred after
-				 * SCSI timeout but before this point.
-				 * Successfully complete it.
-				 */
-				scmd->retries = scmd->allowed;
-				scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
+		if (i < ATA_MAX_QUEUE) {
+			/* the scmd has an associated qc */
+			if (!(qc->flags & ATA_QCFLAG_FAILED)) {
+				/* which hasn't failed yet, timeout */
+				qc->err_mask |= AC_ERR_TIMEOUT;
+				qc->flags |= ATA_QCFLAG_FAILED;
+				nr_timedout++;
 			}
+		} else {
+			/* Normal completion occurred after
+			 * SCSI timeout but before this point.
+			 * Successfully complete it.
+			 */
+			scmd->retries = scmd->allowed;
+			scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
 		}
+	}
 
-		/* If we have timed out qcs.  They belong to EH from
-		 * this point but the state of the controller is
-		 * unknown.  Freeze the port to make sure the IRQ
-		 * handler doesn't diddle with those qcs.  This must
-		 * be done atomically w.r.t. setting QCFLAG_FAILED.
-		 */
-		if (nr_timedout)
-			__ata_port_freeze(ap);
-
+	/* If we have timed out qcs.  They belong to EH from
+	 * this point but the state of the controller is
+	 * unknown.  Freeze the port to make sure the IRQ
+	 * handler doesn't diddle with those qcs.  This must
+	 * be done atomically w.r.t. setting QCFLAG_FAILED.
+	 */
+	if (nr_timedout)
+		__ata_port_freeze(ap);
 
-		/* initialize eh_tries */
-		ap->eh_tries = ATA_EH_MAX_TRIES;
-	}
+	/* initialize eh_tries */
+	ap->eh_tries = ATA_EH_MAX_TRIES;
 	spin_unlock_irqrestore(ap->lock, flags);
 
 }