scsi: hpsa: use local workqueues instead of system workqueues

Avoid system stalls by switching to local workqueue.
Reviewed-by: Justin Lindley <justin.lindley@microsemi.com>
Reviewed-by: David Carroll <david.carroll@microsemi.com>
Reviewed-by: Scott Teel <scott.teel@microsemi.com>
Signed-off-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/hpsa.c

@@ -8128,6 +8128,11 @@ static void hpsa_undo_allocations_after_kdump_soft_reset(struct ctlr_info *h)
 		destroy_workqueue(h->rescan_ctlr_wq);
 		h->rescan_ctlr_wq = NULL;
 	}
+	if (h->monitor_ctlr_wq) {
+		destroy_workqueue(h->monitor_ctlr_wq);
+		h->monitor_ctlr_wq = NULL;
+	}
+
 	kfree(h);				/* init_one 1 */
 }
 
@@ -8463,8 +8468,8 @@ static void hpsa_event_monitor_worker(struct work_struct *work)
 
 	spin_lock_irqsave(&h->lock, flags);
 	if (!h->remove_in_progress)
-		schedule_delayed_work(&h->event_monitor_work,
-					HPSA_EVENT_MONITOR_INTERVAL);
+		queue_delayed_work(h->monitor_ctlr_wq, &h->event_monitor_work,
+				HPSA_EVENT_MONITOR_INTERVAL);
 	spin_unlock_irqrestore(&h->lock, flags);
 }
 
@@ -8509,7 +8514,7 @@ static void hpsa_monitor_ctlr_worker(struct work_struct *work)
 
 	spin_lock_irqsave(&h->lock, flags);
 	if (!h->remove_in_progress)
-		schedule_delayed_work(&h->monitor_ctlr_work,
+		queue_delayed_work(h->monitor_ctlr_wq, &h->monitor_ctlr_work,
 				h->heartbeat_sample_interval);
 	spin_unlock_irqrestore(&h->lock, flags);
 }
@@ -8677,6 +8682,12 @@ static int hpsa_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		goto clean7;	/* aer/h */
 	}
 
+	h->monitor_ctlr_wq = hpsa_create_controller_wq(h, "monitor");
+	if (!h->monitor_ctlr_wq) {
+		rc = -ENOMEM;
+		goto clean7;
+	}
+
 	/*
 	 * At this point, the controller is ready to take commands.
 	 * Now, if reset_devices and the hard reset didn't work, try
@@ -8806,6 +8817,10 @@ static int hpsa_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		destroy_workqueue(h->rescan_ctlr_wq);
 		h->rescan_ctlr_wq = NULL;
 	}
+	if (h->monitor_ctlr_wq) {
+		destroy_workqueue(h->monitor_ctlr_wq);
+		h->monitor_ctlr_wq = NULL;
+	}
 	kfree(h);
 	return rc;
 }
@@ -8953,6 +8968,7 @@ static void hpsa_remove_one(struct pci_dev *pdev)
 	cancel_delayed_work_sync(&h->event_monitor_work);
 	destroy_workqueue(h->rescan_ctlr_wq);
 	destroy_workqueue(h->resubmit_wq);
+	destroy_workqueue(h->monitor_ctlr_wq);
 
 	hpsa_delete_sas_host(h);
 

drivers/scsi/hpsa.h

@@ -300,6 +300,7 @@ struct ctlr_info {
 	int	needs_abort_tags_swizzled;
 	struct workqueue_struct *resubmit_wq;
 	struct workqueue_struct *rescan_ctlr_wq;
+	struct workqueue_struct *monitor_ctlr_wq;
 	atomic_t abort_cmds_available;
 	wait_queue_head_t event_sync_wait_queue;
 	struct mutex reset_mutex;