Commit 1f4a4a19 authored by Tyrel Datwyler's avatar Tyrel Datwyler Committed by Martin K. Petersen
Browse files

scsi: ibmvfc: Complete commands outside the host/queue lock 

Drain the command queue and place all commands on a completion list.
Perform command completion on that list outside the host/queue locks.
Further, move purged command compeletions outside the host_lock as well.

Link: https://lore.kernel.org/r/20210106201835.1053593-5-tyreld@linux.ibm.com


Reviewed-by: default avatarBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: default avatarTyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 57e80e0b

drivers/scsi/ibmvscsi/ibmvfc.c

+45 −13
Original line number Diff line number Diff line
@@ -894,7 +894,7 @@ static void ibmvfc_scsi_eh_done(struct ibmvfc_event *evt) 
 * @purge_list:		list head of failed commands

 *

 * This function runs completions on commands to fail as a result of a

 * host reset or platform migration. Caller must hold host_lock.

 * host reset or platform migration.

 **/

static void ibmvfc_complete_purge(struct list_head *purge_list)

{
@@ -1407,6 +1407,23 @@ static struct ibmvfc_event *ibmvfc_get_event(struct ibmvfc_queue *queue) 
	return evt;

}



/**

 * ibmvfc_locked_done - Calls evt completion with host_lock held

 * @evt:	ibmvfc evt to complete

 *

 * All non-scsi command completion callbacks have the expectation that the

 * host_lock is held. This callback is used by ibmvfc_init_event to wrap a

 * MAD evt with the host_lock.

 **/

static void ibmvfc_locked_done(struct ibmvfc_event *evt)

{

	unsigned long flags;



	spin_lock_irqsave(evt->vhost->host->host_lock, flags);

	evt->_done(evt);

	spin_unlock_irqrestore(evt->vhost->host->host_lock, flags);

}



/**

 * ibmvfc_init_event - Initialize fields in an event struct that are always

 *				required.
@@ -1419,9 +1436,14 @@ static void ibmvfc_init_event(struct ibmvfc_event *evt, 
{

	evt->cmnd = NULL;

	evt->sync_iu = NULL;

	evt->eh_comp = NULL;

	evt->crq.format = format;

	if (format == IBMVFC_CMD_FORMAT)

		evt->done = done;

	evt->eh_comp = NULL;

	else {

		evt->_done = done;

		evt->done = ibmvfc_locked_done;

	}

}



/**
@@ -1640,7 +1662,9 @@ static void ibmvfc_relogin(struct scsi_device *sdev) 
	struct ibmvfc_host *vhost = shost_priv(sdev->host);

	struct fc_rport *rport = starget_to_rport(scsi_target(sdev));

	struct ibmvfc_target *tgt;

	unsigned long flags;



	spin_lock_irqsave(vhost->host->host_lock, flags);

	list_for_each_entry(tgt, &vhost->targets, queue) {

		if (rport == tgt->rport) {

			ibmvfc_del_tgt(tgt);
@@ -1649,6 +1673,7 @@ static void ibmvfc_relogin(struct scsi_device *sdev) 
	}



	ibmvfc_reinit_host(vhost);

	spin_unlock_irqrestore(vhost->host->host_lock, flags);

}



/**
@@ -2901,7 +2926,8 @@ static void ibmvfc_handle_async(struct ibmvfc_async_crq *crq, 
 * @vhost:	ibmvfc host struct

 *

 **/

static void ibmvfc_handle_crq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost)

static void ibmvfc_handle_crq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost,

			      struct list_head *evt_doneq)

{

	long rc;

	struct ibmvfc_event *evt = (struct ibmvfc_event *)be64_to_cpu(crq->ioba);
@@ -2972,12 +2998,9 @@ static void ibmvfc_handle_crq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost) 
		return;

	}



	del_timer(&evt->timer);

	spin_lock(&evt->queue->l_lock);

	list_del(&evt->queue_list);

	list_move_tail(&evt->queue_list, evt_doneq);

	spin_unlock(&evt->queue->l_lock);

	ibmvfc_trc_end(evt);

	evt->done(evt);

}



/**
@@ -3364,8 +3387,10 @@ static void ibmvfc_tasklet(void *data) 
	struct vio_dev *vdev = to_vio_dev(vhost->dev);

	struct ibmvfc_crq *crq;

	struct ibmvfc_async_crq *async;

	struct ibmvfc_event *evt, *temp;

	unsigned long flags;

	int done = 0;

	LIST_HEAD(evt_doneq);



	spin_lock_irqsave(vhost->host->host_lock, flags);

	spin_lock(vhost->crq.q_lock);
@@ -3379,7 +3404,7 @@ static void ibmvfc_tasklet(void *data) 


		/* Pull all the valid messages off the CRQ */

		while ((crq = ibmvfc_next_crq(vhost)) != NULL) {

			ibmvfc_handle_crq(crq, vhost);

			ibmvfc_handle_crq(crq, vhost, &evt_doneq);

			crq->valid = 0;

			wmb();

		}
@@ -3392,7 +3417,7 @@ static void ibmvfc_tasklet(void *data) 
			wmb();

		} else if ((crq = ibmvfc_next_crq(vhost)) != NULL) {

			vio_disable_interrupts(vdev);

			ibmvfc_handle_crq(crq, vhost);

			ibmvfc_handle_crq(crq, vhost, &evt_doneq);

			crq->valid = 0;

			wmb();

		} else
@@ -3401,6 +3426,13 @@ static void ibmvfc_tasklet(void *data) 


	spin_unlock(vhost->crq.q_lock);

	spin_unlock_irqrestore(vhost->host->host_lock, flags);



	list_for_each_entry_safe(evt, temp, &evt_doneq, queue_list) {

		del_timer(&evt->timer);

		list_del(&evt->queue_list);

		ibmvfc_trc_end(evt);

		evt->done(evt);

	}

}



/**
@@ -4790,8 +4822,8 @@ static void ibmvfc_do_work(struct ibmvfc_host *vhost) 
	case IBMVFC_HOST_ACTION_RESET:

		vhost->action = IBMVFC_HOST_ACTION_TGT_DEL;

		list_splice_init(&vhost->purge, &purge);

		ibmvfc_complete_purge(&purge);

		spin_unlock_irqrestore(vhost->host->host_lock, flags);

		ibmvfc_complete_purge(&purge);

		rc = ibmvfc_reset_crq(vhost);

		spin_lock_irqsave(vhost->host->host_lock, flags);

		if (rc == H_CLOSED)
@@ -4805,8 +4837,8 @@ static void ibmvfc_do_work(struct ibmvfc_host *vhost) 
	case IBMVFC_HOST_ACTION_REENABLE:

		vhost->action = IBMVFC_HOST_ACTION_TGT_DEL;

		list_splice_init(&vhost->purge, &purge);

		ibmvfc_complete_purge(&purge);

		spin_unlock_irqrestore(vhost->host->host_lock, flags);

		ibmvfc_complete_purge(&purge);

		rc = ibmvfc_reenable_crq_queue(vhost);

		spin_lock_irqsave(vhost->host->host_lock, flags);

		if (rc || (rc = ibmvfc_send_crq_init(vhost))) {
@@ -5369,8 +5401,8 @@ static int ibmvfc_remove(struct vio_dev *vdev) 
	spin_lock_irqsave(vhost->host->host_lock, flags);

	ibmvfc_purge_requests(vhost, DID_ERROR);

	list_splice_init(&vhost->purge, &purge);

	ibmvfc_complete_purge(&purge);

	spin_unlock_irqrestore(vhost->host->host_lock, flags);

	ibmvfc_complete_purge(&purge);

	ibmvfc_free_event_pool(vhost, &vhost->crq);



	ibmvfc_free_mem(vhost);

drivers/scsi/ibmvscsi/ibmvfc.h

+2 −1
Original line number Diff line number Diff line
@@ -733,7 +733,8 @@ struct ibmvfc_event { 
	struct scsi_cmnd *cmnd;

	atomic_t free;

	union ibmvfc_iu *xfer_iu;

	void (*done) (struct ibmvfc_event *);

	void (*done)(struct ibmvfc_event *evt);

	void (*_done)(struct ibmvfc_event *evt);

	struct ibmvfc_crq crq;

	union ibmvfc_iu iu;

	union ibmvfc_iu *sync_iu;