diff mbox series

[3/6] scsi: iscsi: Remove iscsi_scan_finished.

Message ID 20220226230435.38733-4-michael.christie@oracle.com
State New
Headers show
Series iscsi: Speed up failover with lots of devices. | expand

Commit Message

Mike Christie Feb. 26, 2022, 11:04 p.m. UTC
qla4xxx does not use iscsi_scan_finished anymore so remove it.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
---
 drivers/scsi/scsi_transport_iscsi.c | 39 +++--------------------------
 include/scsi/scsi_transport_iscsi.h |  2 --
 2 files changed, 4 insertions(+), 37 deletions(-)

Comments

Lee Duncan Feb. 28, 2022, 6:05 p.m. UTC | #1
On 2/26/22 15:04, Mike Christie wrote:
> qla4xxx does not use iscsi_scan_finished anymore so remove it.
> 
> Signed-off-by: Mike Christie <michael.christie@oracle.com>
> ---
>   drivers/scsi/scsi_transport_iscsi.c | 39 +++--------------------------
>   include/scsi/scsi_transport_iscsi.h |  2 --
>   2 files changed, 4 insertions(+), 37 deletions(-)
> 
> diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
> index 732938f5436b..05cd4bca979e 100644
> --- a/drivers/scsi/scsi_transport_iscsi.c
> +++ b/drivers/scsi/scsi_transport_iscsi.c
> @@ -1557,7 +1557,6 @@ static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
>   	struct iscsi_cls_host *ihost = shost->shost_data;
>   
>   	memset(ihost, 0, sizeof(*ihost));
> -	atomic_set(&ihost->nr_scans, 0);
>   	mutex_init(&ihost->mutex);
>   
>   	iscsi_bsg_host_add(shost, ihost);
> @@ -1744,25 +1743,6 @@ void iscsi_host_for_each_session(struct Scsi_Host *shost,
>   }
>   EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
>   
> -/**
> - * iscsi_scan_finished - helper to report when running scans are done
> - * @shost: scsi host
> - * @time: scan run time
> - *
> - * This function can be used by drives like qla4xxx to report to the scsi
> - * layer when the scans it kicked off at module load time are done.
> - */
> -int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
> -{
> -	struct iscsi_cls_host *ihost = shost->shost_data;
> -	/*
> -	 * qla4xxx will have kicked off some session unblocks before calling
> -	 * scsi_scan_host, so just wait for them to complete.
> -	 */
> -	return !atomic_read(&ihost->nr_scans);
> -}
> -EXPORT_SYMBOL_GPL(iscsi_scan_finished);
> -
>   struct iscsi_scan_data {
>   	unsigned int channel;
>   	unsigned int id;
> @@ -1831,8 +1811,6 @@ static void iscsi_scan_session(struct work_struct *work)
>   {
>   	struct iscsi_cls_session *session =
>   			container_of(work, struct iscsi_cls_session, scan_work);
> -	struct Scsi_Host *shost = iscsi_session_to_shost(session);
> -	struct iscsi_cls_host *ihost = shost->shost_data;
>   	struct iscsi_scan_data scan_data;
>   
>   	scan_data.channel = 0;
> @@ -1841,7 +1819,6 @@ static void iscsi_scan_session(struct work_struct *work)
>   	scan_data.rescan = SCSI_SCAN_RESCAN;
>   
>   	iscsi_user_scan_session(&session->dev, &scan_data);
> -	atomic_dec(&ihost->nr_scans);
>   }
>   
>   /**
> @@ -1912,8 +1889,6 @@ static void __iscsi_unblock_session(struct work_struct *work)
>   	struct iscsi_cls_session *session =
>   			container_of(work, struct iscsi_cls_session,
>   				     unblock_work);
> -	struct Scsi_Host *shost = iscsi_session_to_shost(session);
> -	struct iscsi_cls_host *ihost = shost->shost_data;
>   	unsigned long flags;
>   
>   	ISCSI_DBG_TRANS_SESSION(session, "Unblocking session\n");
> @@ -1924,15 +1899,6 @@ static void __iscsi_unblock_session(struct work_struct *work)
>   	spin_unlock_irqrestore(&session->lock, flags);
>   	/* start IO */
>   	scsi_target_unblock(&session->dev, SDEV_RUNNING);
> -	/*
> -	 * Only do kernel scanning if the driver is properly hooked into
> -	 * the async scanning code (drivers like iscsi_tcp do login and
> -	 * scanning from userspace).
> -	 */
> -	if (shost->hostt->scan_finished) {
> -		if (scsi_queue_work(shost, &session->scan_work))
> -			atomic_inc(&ihost->nr_scans);
> -	}
>   	ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking session\n");
>   }
>   
> @@ -2192,7 +2158,10 @@ void iscsi_remove_session(struct iscsi_cls_session *session)
>   	spin_unlock_irqrestore(&session->lock, flags);
>   
>   	scsi_target_unblock(&session->dev, SDEV_TRANSPORT_OFFLINE);
> -	/* flush running scans then delete devices */
> +	/*
> +	 * qla4xxx can perform it's own scans when it runs in kernel only
> +	 * mode. Make sure to flush those scans.
> +	 */
>   	flush_work(&session->scan_work);
>   	/* flush running unbind operations */
>   	flush_work(&session->unbind_work);
> diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
> index c5d7810fd792..90b55db46d7c 100644
> --- a/include/scsi/scsi_transport_iscsi.h
> +++ b/include/scsi/scsi_transport_iscsi.h
> @@ -278,7 +278,6 @@ struct iscsi_cls_session {
>   	iscsi_dev_to_session(_stgt->dev.parent)
>   
>   struct iscsi_cls_host {
> -	atomic_t nr_scans;
>   	struct mutex mutex;
>   	struct request_queue *bsg_q;
>   	uint32_t port_speed;
> @@ -448,7 +447,6 @@ extern void iscsi_get_conn(struct iscsi_cls_conn *conn);
>   extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
>   extern void iscsi_unblock_session(struct iscsi_cls_session *session);
>   extern void iscsi_block_session(struct iscsi_cls_session *session);
> -extern int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time);
>   extern struct iscsi_endpoint *iscsi_create_endpoint(int dd_size);
>   extern void iscsi_destroy_endpoint(struct iscsi_endpoint *ep);
>   extern struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle);

I have no issue with this, but it seems kind of unrelated to speeding up 
session unblocking ... Never the less:

Reviewed-by: Lee Duncan <lduncan@suse.com>
Chris Leech Feb. 28, 2022, 8:07 p.m. UTC | #2
On 2/26/22 3:04 PM, Mike Christie wrote:
> qla4xxx does not use iscsi_scan_finished anymore so remove it.
> 
> Signed-off-by: Mike Christie <michael.christie@oracle.com>
> ---
>  drivers/scsi/scsi_transport_iscsi.c | 39 +++--------------------------
>  include/scsi/scsi_transport_iscsi.h |  2 --
>  2 files changed, 4 insertions(+), 37 deletions(-)
> 
> diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
> index 732938f5436b..05cd4bca979e 100644
> --- a/drivers/scsi/scsi_transport_iscsi.c
> +++ b/drivers/scsi/scsi_transport_iscsi.c
> @@ -1557,7 +1557,6 @@ static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
>  	struct iscsi_cls_host *ihost = shost->shost_data;
>  
>  	memset(ihost, 0, sizeof(*ihost));
> -	atomic_set(&ihost->nr_scans, 0);
>  	mutex_init(&ihost->mutex);
>  
>  	iscsi_bsg_host_add(shost, ihost);
> @@ -1744,25 +1743,6 @@ void iscsi_host_for_each_session(struct Scsi_Host *shost,
>  }
>  EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
>  
> -/**
> - * iscsi_scan_finished - helper to report when running scans are done
> - * @shost: scsi host
> - * @time: scan run time
> - *
> - * This function can be used by drives like qla4xxx to report to the scsi
> - * layer when the scans it kicked off at module load time are done.
> - */
> -int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
> -{
> -	struct iscsi_cls_host *ihost = shost->shost_data;
> -	/*
> -	 * qla4xxx will have kicked off some session unblocks before calling
> -	 * scsi_scan_host, so just wait for them to complete.
> -	 */
> -	return !atomic_read(&ihost->nr_scans);
> -}
> -EXPORT_SYMBOL_GPL(iscsi_scan_finished);
> -
>  struct iscsi_scan_data {
>  	unsigned int channel;
>  	unsigned int id;
> @@ -1831,8 +1811,6 @@ static void iscsi_scan_session(struct work_struct *work)
>  {
>  	struct iscsi_cls_session *session =
>  			container_of(work, struct iscsi_cls_session, scan_work);
> -	struct Scsi_Host *shost = iscsi_session_to_shost(session);
> -	struct iscsi_cls_host *ihost = shost->shost_data;
>  	struct iscsi_scan_data scan_data;
>  
>  	scan_data.channel = 0;
> @@ -1841,7 +1819,6 @@ static void iscsi_scan_session(struct work_struct *work)
>  	scan_data.rescan = SCSI_SCAN_RESCAN;
>  
>  	iscsi_user_scan_session(&session->dev, &scan_data);
> -	atomic_dec(&ihost->nr_scans);
>  }
>  
>  /**
> @@ -1912,8 +1889,6 @@ static void __iscsi_unblock_session(struct work_struct *work)
>  	struct iscsi_cls_session *session =
>  			container_of(work, struct iscsi_cls_session,
>  				     unblock_work);
> -	struct Scsi_Host *shost = iscsi_session_to_shost(session);
> -	struct iscsi_cls_host *ihost = shost->shost_data;
>  	unsigned long flags;
>  
>  	ISCSI_DBG_TRANS_SESSION(session, "Unblocking session\n");
> @@ -1924,15 +1899,6 @@ static void __iscsi_unblock_session(struct work_struct *work)
>  	spin_unlock_irqrestore(&session->lock, flags);
>  	/* start IO */
>  	scsi_target_unblock(&session->dev, SDEV_RUNNING);
> -	/*
> -	 * Only do kernel scanning if the driver is properly hooked into
> -	 * the async scanning code (drivers like iscsi_tcp do login and
> -	 * scanning from userspace).
> -	 */
> -	if (shost->hostt->scan_finished) {
> -		if (scsi_queue_work(shost, &session->scan_work))
> -			atomic_inc(&ihost->nr_scans);
> -	}
>  	ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking session\n");
>  }
>  
> @@ -2192,7 +2158,10 @@ void iscsi_remove_session(struct iscsi_cls_session *session)
>  	spin_unlock_irqrestore(&session->lock, flags);
>  
>  	scsi_target_unblock(&session->dev, SDEV_TRANSPORT_OFFLINE);
> -	/* flush running scans then delete devices */
> +	/*
> +	 * qla4xxx can perform it's own scans when it runs in kernel only
> +	 * mode. Make sure to flush those scans.
> +	 */
>  	flush_work(&session->scan_work);
>  	/* flush running unbind operations */
>  	flush_work(&session->unbind_work);
> diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
> index c5d7810fd792..90b55db46d7c 100644
> --- a/include/scsi/scsi_transport_iscsi.h
> +++ b/include/scsi/scsi_transport_iscsi.h
> @@ -278,7 +278,6 @@ struct iscsi_cls_session {
>  	iscsi_dev_to_session(_stgt->dev.parent)
>  
>  struct iscsi_cls_host {
> -	atomic_t nr_scans;
>  	struct mutex mutex;
>  	struct request_queue *bsg_q;
>  	uint32_t port_speed;
> @@ -448,7 +447,6 @@ extern void iscsi_get_conn(struct iscsi_cls_conn *conn);
>  extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
>  extern void iscsi_unblock_session(struct iscsi_cls_session *session);
>  extern void iscsi_block_session(struct iscsi_cls_session *session);
> -extern int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time);
>  extern struct iscsi_endpoint *iscsi_create_endpoint(int dd_size);
>  extern void iscsi_destroy_endpoint(struct iscsi_endpoint *ep);
>  extern struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle);

Reviewed-by: Chris Leech <cleech@redhat.com>
Mike Christie Feb. 28, 2022, 8:39 p.m. UTC | #3
On 2/28/22 12:05 PM, Lee Duncan wrote:
>> -    if (shost->hostt->scan_finished) {
>> -        if (scsi_queue_work(shost, &session->scan_work))
>> -            atomic_inc(&ihost->nr_scans);
>> -    }
>>       ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking session\n");
>>   }

....

> 
> I have no issue with this, but it seems kind of unrelated to speeding up session unblocking 

It's related because in the next patch we stop creating the host's transport
wq which is used above in the chunk that was removed in __iscsi_unblock_session.
diff mbox series

Patch

diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 732938f5436b..05cd4bca979e 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -1557,7 +1557,6 @@  static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
 	struct iscsi_cls_host *ihost = shost->shost_data;
 
 	memset(ihost, 0, sizeof(*ihost));
-	atomic_set(&ihost->nr_scans, 0);
 	mutex_init(&ihost->mutex);
 
 	iscsi_bsg_host_add(shost, ihost);
@@ -1744,25 +1743,6 @@  void iscsi_host_for_each_session(struct Scsi_Host *shost,
 }
 EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
 
-/**
- * iscsi_scan_finished - helper to report when running scans are done
- * @shost: scsi host
- * @time: scan run time
- *
- * This function can be used by drives like qla4xxx to report to the scsi
- * layer when the scans it kicked off at module load time are done.
- */
-int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
-{
-	struct iscsi_cls_host *ihost = shost->shost_data;
-	/*
-	 * qla4xxx will have kicked off some session unblocks before calling
-	 * scsi_scan_host, so just wait for them to complete.
-	 */
-	return !atomic_read(&ihost->nr_scans);
-}
-EXPORT_SYMBOL_GPL(iscsi_scan_finished);
-
 struct iscsi_scan_data {
 	unsigned int channel;
 	unsigned int id;
@@ -1831,8 +1811,6 @@  static void iscsi_scan_session(struct work_struct *work)
 {
 	struct iscsi_cls_session *session =
 			container_of(work, struct iscsi_cls_session, scan_work);
-	struct Scsi_Host *shost = iscsi_session_to_shost(session);
-	struct iscsi_cls_host *ihost = shost->shost_data;
 	struct iscsi_scan_data scan_data;
 
 	scan_data.channel = 0;
@@ -1841,7 +1819,6 @@  static void iscsi_scan_session(struct work_struct *work)
 	scan_data.rescan = SCSI_SCAN_RESCAN;
 
 	iscsi_user_scan_session(&session->dev, &scan_data);
-	atomic_dec(&ihost->nr_scans);
 }
 
 /**
@@ -1912,8 +1889,6 @@  static void __iscsi_unblock_session(struct work_struct *work)
 	struct iscsi_cls_session *session =
 			container_of(work, struct iscsi_cls_session,
 				     unblock_work);
-	struct Scsi_Host *shost = iscsi_session_to_shost(session);
-	struct iscsi_cls_host *ihost = shost->shost_data;
 	unsigned long flags;
 
 	ISCSI_DBG_TRANS_SESSION(session, "Unblocking session\n");
@@ -1924,15 +1899,6 @@  static void __iscsi_unblock_session(struct work_struct *work)
 	spin_unlock_irqrestore(&session->lock, flags);
 	/* start IO */
 	scsi_target_unblock(&session->dev, SDEV_RUNNING);
-	/*
-	 * Only do kernel scanning if the driver is properly hooked into
-	 * the async scanning code (drivers like iscsi_tcp do login and
-	 * scanning from userspace).
-	 */
-	if (shost->hostt->scan_finished) {
-		if (scsi_queue_work(shost, &session->scan_work))
-			atomic_inc(&ihost->nr_scans);
-	}
 	ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking session\n");
 }
 
@@ -2192,7 +2158,10 @@  void iscsi_remove_session(struct iscsi_cls_session *session)
 	spin_unlock_irqrestore(&session->lock, flags);
 
 	scsi_target_unblock(&session->dev, SDEV_TRANSPORT_OFFLINE);
-	/* flush running scans then delete devices */
+	/*
+	 * qla4xxx can perform it's own scans when it runs in kernel only
+	 * mode. Make sure to flush those scans.
+	 */
 	flush_work(&session->scan_work);
 	/* flush running unbind operations */
 	flush_work(&session->unbind_work);
diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index c5d7810fd792..90b55db46d7c 100644
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -278,7 +278,6 @@  struct iscsi_cls_session {
 	iscsi_dev_to_session(_stgt->dev.parent)
 
 struct iscsi_cls_host {
-	atomic_t nr_scans;
 	struct mutex mutex;
 	struct request_queue *bsg_q;
 	uint32_t port_speed;
@@ -448,7 +447,6 @@  extern void iscsi_get_conn(struct iscsi_cls_conn *conn);
 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
 extern void iscsi_unblock_session(struct iscsi_cls_session *session);
 extern void iscsi_block_session(struct iscsi_cls_session *session);
-extern int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time);
 extern struct iscsi_endpoint *iscsi_create_endpoint(int dd_size);
 extern void iscsi_destroy_endpoint(struct iscsi_endpoint *ep);
 extern struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle);