Hi,


Thanks for you noticed my change.


On 2023/7/20 03:32, Bjorn Helgaas wrote:

quoted

@@ -1509,13 +1543,24 @@ static int pci_notify(struct notifier_block *nb, unsigned long action,
  	 * cases of hotplugable vga cards.
  	 */
  
-	if (action == BUS_NOTIFY_ADD_DEVICE)
+	switch (action) {
+	case BUS_NOTIFY_ADD_DEVICE:
  		notify = vga_arbiter_add_pci_device(pdev);
-	else if (action == BUS_NOTIFY_DEL_DEVICE)
+		if (notify)
+			vga_arbiter_notify_clients();
+		break;
+	case BUS_NOTIFY_DEL_DEVICE:
  		notify = vga_arbiter_del_pci_device(pdev);
+		if (notify)
+			vga_arbiter_notify_clients();
+		break;
+	case BUS_NOTIFY_BOUND_DRIVER:
+		vga_arbiter_do_arbitration(pdev);
+		break;
+	default:
+		break;
+	}

Changing from if/else to switch makes the patch bigger than necessary
for no real benefit and obscures what is really changing.

Actually, the logic become more clear after this patch applied.

     switch (action) {
     case BUS_NOTIFY_ADD_DEVICE:
         notify = vga_arbiter_add_pci_device(pdev);
         if (notify)
             vga_arbiter_notify_clients();
         break;
     case BUS_NOTIFY_DEL_DEVICE:
         notify = vga_arbiter_del_pci_device(pdev);
         if (notify)
             vga_arbiter_notify_clients();
         break;
     case BUS_NOTIFY_BOUND_DRIVER:
         vga_arbiter_do_arbitration(pdev);
         break;
     default:
         break;
     }

Because we only need call vga_arbiter_notify_clients() when action == 
BUS_NOTIFY_ADD_DEVICE or action == BUS_NOTIFY_DEL_DEVICE,

But *NOT* when the action equals to  BUS_NOTIFY_BOUND_DRIVER.