usb: hub: keep hub->dev reference all the time when struct usb_hub lives (5d14f323) · Commits · 戴 / test

This is just a small optimization of the fix from the commit ("usb: hub: take hub->hdev reference when processing from eventlist). We do not need to take the reference for each event. Instead we could get it when struct usb_hub is allocated and put it when it is released. By other words, we could handle it the same way as the reference for hub->intfdev. The motivation is that it will make the life easier when switching from khubd kthread to a workqueue. Suggested-by:

Alan Stern <stern@rowland.harvard.edu> Signed-off-by:

Petr Mladek <pmladek@suse.cz> Acked-by:

Alan Stern <stern@rowland.harvard.edu> Signed-off-by:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/core/hub.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -1635,6 +1635,7 @@ static void hub_release(struct kref *kref)
		{
		struct usb_hub *hub = container_of(kref, struct usb_hub, kref);

		usb_put_dev(hub->hdev);
		usb_put_intf(to_usb_interface(hub->intfdev));
		kfree(hub);
		}
		@@ -1800,6 +1801,7 @@ descriptor_error:
		INIT_DELAYED_WORK(&hub->leds, led_work);
		INIT_DELAYED_WORK(&hub->init_work, NULL);
		usb_get_intf(intf);
		usb_get_dev(hdev);

		usb_set_intfdata (intf, hub);
		intf->needs_remote_wakeup = 1;
		@@ -5026,10 +5028,9 @@ static void hub_events(void)

		hub = list_entry(tmp, struct usb_hub, event_list);
		kref_get(&hub->kref);
		hdev = hub->hdev;
		usb_get_dev(hdev);
		spin_unlock_irq(&hub_event_lock);

		hdev = hub->hdev;
		hub_dev = hub->intfdev;
		intf = to_usb_interface(hub_dev);
		dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
		@@ -5142,7 +5143,6 @@ static void hub_events(void)
		usb_autopm_put_interface(intf);
		loop_disconnected:
		usb_unlock_device(hdev);
		usb_put_dev(hdev);
		kref_put(&hub->kref, hub_release);

		} /* end while (1) */

Admin message