PCI: pciehp: Handle push button event asynchronously

Use non-ordered workqueue for attention button events.

Attention button events on each slot can be handled asynchronously. So
we should use non-ordered workqueue. This patch also removes ordered
workqueue in pciehp as a result.

Signed-off-by: Kenji Kaneshige <[email protected]>
Signed-off-by: Jesse Barnes <[email protected]>

Author: kkaneshige

drivers/pci/hotplug/pciehp.h

@@ -45,7 +45,6 @@ extern int pciehp_poll_time;
 extern int pciehp_debug;
 extern int pciehp_force;
 extern struct workqueue_struct *pciehp_wq;
-extern struct workqueue_struct *pciehp_ordered_wq;
 
 #define dbg(format, arg...)						\
 do {									\

drivers/pci/hotplug/pciehp_core.c

@@ -43,7 +43,6 @@ int pciehp_poll_mode;
 int pciehp_poll_time;
 int pciehp_force;
 struct workqueue_struct *pciehp_wq;
-struct workqueue_struct *pciehp_ordered_wq;
 
 #define DRIVER_VERSION	"0.4"
 #define DRIVER_AUTHOR	"Dan Zink <[email protected]>, Greg Kroah-Hartman <[email protected]>, Dely Sy <[email protected]>"
@@ -345,18 +344,11 @@ static int __init pcied_init(void)
 	if (!pciehp_wq)
 		return -ENOMEM;
 
-	pciehp_ordered_wq = alloc_ordered_workqueue("pciehp_ordered", 0);
-	if (!pciehp_ordered_wq) {
-		destroy_workqueue(pciehp_wq);
-		return -ENOMEM;
-	}
-
 	pciehp_firmware_init();
 	retval = pcie_port_service_register(&hpdriver_portdrv);
  	dbg("pcie_port_service_register = %d\n", retval);
   	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
  	if (retval) {
-		destroy_workqueue(pciehp_ordered_wq);
 		destroy_workqueue(pciehp_wq);
 		dbg("Failure to register service\n");
 	}
@@ -367,7 +359,6 @@ static void __exit pcied_cleanup(void)
 {
 	dbg("unload_pciehpd()\n");
 	pcie_port_service_unregister(&hpdriver_portdrv);
-	destroy_workqueue(pciehp_ordered_wq);
 	destroy_workqueue(pciehp_wq);
 	info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
 }

drivers/pci/hotplug/pciehp_ctrl.c

@@ -344,7 +344,7 @@ void pciehp_queue_pushbutton_work(struct work_struct *work)
 		kfree(info);
 		goto out;
 	}
-	queue_work(pciehp_ordered_wq, &info->work);
+	queue_work(pciehp_wq, &info->work);
  out:
 	mutex_unlock(&p_slot->lock);
 }
@@ -439,7 +439,7 @@ static void handle_surprise_event(struct slot *p_slot)
 	else
 		p_slot->state = POWERON_STATE;
 
-	queue_work(pciehp_ordered_wq, &info->work);
+	queue_work(pciehp_wq, &info->work);
 }
 
 static void interrupt_event_handler(struct work_struct *work)

drivers/pci/hotplug/pciehp_hpc.c

@@ -806,7 +806,6 @@ static void pcie_cleanup_slot(struct controller *ctrl)
 	struct slot *slot = ctrl->slot;
 	cancel_delayed_work(&slot->work);
 	flush_workqueue(pciehp_wq);
-	flush_workqueue(pciehp_ordered_wq);
 	kfree(slot);
 }