Commit 25236d48 authored by Ewan D. Milne's avatar Ewan D. Milne Committed by Martin K. Petersen
Browse files

scsi: scsi_transport_fc: Change to use per-rport devloss_work_q 



Configurations with large numbers of FC rports per host instance are
taking a very long time to complete all devloss work.  Increase potential
parallelism by using a per-rport devloss_work_q for dev_loss_work and
fast_io_fail_work.

Signed-off-by: default avatarEwan D. Milne <emilne@redhat.com>
Link: https://lore.kernel.org/r/20250707202225.1203189-1-emilne@redhat.com


Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 01aad16c

drivers/scsi/scsi_transport_fc.c

+40 −30
Original line number Diff line number Diff line
@@ -446,13 +446,6 @@ static int fc_host_setup(struct transport_container *tc, struct device *dev, 
		return -ENOMEM;



	fc_host->dev_loss_tmo = fc_dev_loss_tmo;

	fc_host->devloss_work_q = alloc_workqueue("fc_dl_%d", 0, 0,

					shost->host_no);

	if (!fc_host->devloss_work_q) {

		destroy_workqueue(fc_host->work_q);

		fc_host->work_q = NULL;

		return -ENOMEM;

	}



	fc_bsg_hostadd(shost, fc_host);

	/* ignore any bsg add error - we just can't do sgio */
@@ -2821,10 +2814,10 @@ fc_flush_work(struct Scsi_Host *shost) 
 * 	1 on success / 0 already queued / < 0 for error

 */

static int

fc_queue_devloss_work(struct Scsi_Host *shost, struct delayed_work *work,

				unsigned long delay)

fc_queue_devloss_work(struct Scsi_Host *shost, struct fc_rport *rport,

		      struct delayed_work *work, unsigned long delay)

{

	if (unlikely(!fc_host_devloss_work_q(shost))) {

	if (unlikely(!rport->devloss_work_q)) {

		printk(KERN_ERR

			"ERROR: FC host '%s' attempted to queue work, "

			"when no workqueue created.\n", shost->hostt->name);
@@ -2833,7 +2826,7 @@ fc_queue_devloss_work(struct Scsi_Host *shost, struct delayed_work *work, 
		return -EINVAL;

	}



	return queue_delayed_work(fc_host_devloss_work_q(shost), work, delay);

	return queue_delayed_work(rport->devloss_work_q, work, delay);

}



/**
@@ -2841,9 +2834,9 @@ fc_queue_devloss_work(struct Scsi_Host *shost, struct delayed_work *work, 
 * @shost:	Pointer to Scsi_Host bound to fc_host.

 */

static void

fc_flush_devloss(struct Scsi_Host *shost)

fc_flush_devloss(struct Scsi_Host *shost, struct fc_rport *rport)

{

	if (!fc_host_devloss_work_q(shost)) {

	if (unlikely(!rport->devloss_work_q)) {

		printk(KERN_ERR

			"ERROR: FC host '%s' attempted to flush work, "

			"when no workqueue created.\n", shost->hostt->name);
@@ -2851,7 +2844,7 @@ fc_flush_devloss(struct Scsi_Host *shost) 
		return;

	}



	flush_workqueue(fc_host_devloss_work_q(shost));

	flush_workqueue(rport->devloss_work_q);

}
@@ -2913,13 +2906,6 @@ fc_remove_host(struct Scsi_Host *shost) 
		fc_host->work_q = NULL;

		destroy_workqueue(work_q);

	}



	/* flush all devloss work items, then kill it  */

	if (fc_host->devloss_work_q) {

		work_q = fc_host->devloss_work_q;

		fc_host->devloss_work_q = NULL;

		destroy_workqueue(work_q);

	}

}

EXPORT_SYMBOL(fc_remove_host);
@@ -2967,6 +2953,7 @@ fc_rport_final_delete(struct work_struct *work) 
	struct device *dev = &rport->dev;

	struct Scsi_Host *shost = rport_to_shost(rport);

	struct fc_internal *i = to_fc_internal(shost->transportt);

	struct workqueue_struct *work_q;

	unsigned long flags;

	int do_callback = 0;
@@ -2988,9 +2975,9 @@ fc_rport_final_delete(struct work_struct *work) 
	if (rport->flags & FC_RPORT_DEVLOSS_PENDING) {

		spin_unlock_irqrestore(shost->host_lock, flags);

		if (!cancel_delayed_work(&rport->fail_io_work))

			fc_flush_devloss(shost);

			fc_flush_devloss(shost, rport);

		if (!cancel_delayed_work(&rport->dev_loss_work))

			fc_flush_devloss(shost);

			fc_flush_devloss(shost, rport);

		cancel_work_sync(&rport->scan_work);

		spin_lock_irqsave(shost->host_lock, flags);

		rport->flags &= ~FC_RPORT_DEVLOSS_PENDING;
@@ -3021,6 +3008,12 @@ fc_rport_final_delete(struct work_struct *work) 


	fc_bsg_remove(rport->rqst_q);



	if (rport->devloss_work_q) {

		work_q = rport->devloss_work_q;

		rport->devloss_work_q = NULL;

		destroy_workqueue(work_q);

	}



	transport_remove_device(dev);

	device_del(dev);

	transport_destroy_device(dev);
@@ -3093,6 +3086,22 @@ fc_remote_port_create(struct Scsi_Host *shost, int channel, 


	spin_unlock_irqrestore(shost->host_lock, flags);



	rport->devloss_work_q = alloc_workqueue("fc_dl_%d_%d", 0, 0,

						shost->host_no, rport->number);

	if (!rport->devloss_work_q) {

		printk(KERN_ERR "FC Remote Port alloc_workqueue failed\n");

/*

 * Note that we have not yet called device_initialize() / get_device()

 * Cannot reclaim incremented rport->number because we released host_lock

 */

		spin_lock_irqsave(shost->host_lock, flags);

		list_del(&rport->peers);

		scsi_host_put(shost);			/* for fc_host->rport list */

		spin_unlock_irqrestore(shost->host_lock, flags);

		kfree(rport);

		return NULL;

	}



	dev = &rport->dev;

	device_initialize(dev);			/* takes self reference */

	dev->parent = get_device(&shost->shost_gendev); /* parent reference */
@@ -3255,9 +3264,9 @@ fc_remote_port_add(struct Scsi_Host *shost, int channel, 
				 * be checked and will NOOP the function.

				 */

				if (!cancel_delayed_work(&rport->fail_io_work))

					fc_flush_devloss(shost);

					fc_flush_devloss(shost, rport);

				if (!cancel_delayed_work(&rport->dev_loss_work))

					fc_flush_devloss(shost);

					fc_flush_devloss(shost, rport);



				spin_lock_irqsave(shost->host_lock, flags);
@@ -3451,11 +3460,12 @@ fc_remote_port_delete(struct fc_rport *rport) 
	/* see if we need to kill io faster than waiting for device loss */

	if ((rport->fast_io_fail_tmo != -1) &&

	    (rport->fast_io_fail_tmo < timeout))

		fc_queue_devloss_work(shost, &rport->fail_io_work,

		fc_queue_devloss_work(shost, rport, &rport->fail_io_work,

				      rport->fast_io_fail_tmo * HZ);



	/* cap the length the devices can be blocked until they are deleted */

	fc_queue_devloss_work(shost, &rport->dev_loss_work, timeout * HZ);

	fc_queue_devloss_work(shost, rport, &rport->dev_loss_work,

			      timeout * HZ);

}

EXPORT_SYMBOL(fc_remote_port_delete);
@@ -3514,9 +3524,9 @@ fc_remote_port_rolechg(struct fc_rport *rport, u32 roles) 
		 * transaction.

		 */

		if (!cancel_delayed_work(&rport->fail_io_work))

			fc_flush_devloss(shost);

			fc_flush_devloss(shost, rport);

		if (!cancel_delayed_work(&rport->dev_loss_work))

			fc_flush_devloss(shost);

			fc_flush_devloss(shost, rport);



		spin_lock_irqsave(shost->host_lock, flags);

		rport->flags &= ~(FC_RPORT_FAST_FAIL_TIMEDOUT |

include/scsi/scsi_transport_fc.h

+2 −3
Original line number Diff line number Diff line
@@ -383,6 +383,8 @@ struct fc_rport { /* aka fc_starget_attrs */ 
 	struct work_struct stgt_delete_work;

	struct work_struct rport_delete_work;

	struct request_queue *rqst_q;	/* bsg support */



	struct workqueue_struct *devloss_work_q;

} __attribute__((aligned(sizeof(unsigned long))));



/* bit field values for struct fc_rport "flags" field: */
@@ -576,7 +578,6 @@ struct fc_host_attrs { 


	/* work queues for rport state manipulation */

	struct workqueue_struct *work_q;

	struct workqueue_struct *devloss_work_q;



	/* bsg support */

	struct request_queue *rqst_q;
@@ -654,8 +655,6 @@ struct fc_host_attrs { 
	(((struct fc_host_attrs *)(x)->shost_data)->npiv_vports_inuse)

#define fc_host_work_q(x) \

	(((struct fc_host_attrs *)(x)->shost_data)->work_q)

#define fc_host_devloss_work_q(x) \

	(((struct fc_host_attrs *)(x)->shost_data)->devloss_work_q)

#define fc_host_dev_loss_tmo(x) \

	(((struct fc_host_attrs *)(x)->shost_data)->dev_loss_tmo)

#define fc_host_max_ct_payload(x)  \