diff mbox series

[1/3] xhci: Avoid queuing redundant Stop Endpoint command for stalled endpoint

Message ID 20250311154551.4035726-2-mathias.nyman@linux.intel.com (mailing list archive)
State New
Headers show
Series xhci features for usb-next | expand

Commit Message

Mathias Nyman March 11, 2025, 3:45 p.m. UTC
If EP_STALLED flag is set in xhci_urb_dequeue(), without EP_HALTED or
SET_DEQ_PENDING flags, then the endpoint is in stopped state and the
cancelled URB can be given back immediately withouth queueing
a 'stop endpoint' command.

Without this change the cancelled URB would eventually be given back
in the 'context state error' completion path of the 'stop endpoint'
command. This is not optimal.

For this improvement to work the EP_STALLED flag must be cleared with
xhci lock held.

Suggested-by: Michal Pecio <michal.pecio@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
---
 drivers/usb/host/xhci.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 1852175f48c1..19e308f4fc06 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1773,8 +1773,8 @@  static int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 		goto done;
 	}
 
-	/* In this case no commands are pending but the endpoint is stopped */
-	if (ep->ep_state & EP_CLEARING_TT) {
+	/* In these cases no commands are pending but the endpoint is stopped */
+	if (ep->ep_state & (EP_CLEARING_TT | EP_STALLED)) {
 		/* and cancelled TDs can be given back right away */
 		xhci_dbg(xhci, "Invalidating TDs instantly on slot %d ep %d in state 0x%x\n",
 				urb->dev->slot_id, ep_index, ep->ep_state);
@@ -3211,10 +3211,12 @@  static void xhci_endpoint_reset(struct usb_hcd *hcd,
 		return;
 
 	ep = &vdev->eps[ep_index];
+
+	spin_lock_irqsave(&xhci->lock, flags);
+
 	ep->ep_state &= ~EP_STALLED;
 
 	/* Bail out if toggle is already being cleared by a endpoint reset */
-	spin_lock_irqsave(&xhci->lock, flags);
 	if (ep->ep_state & EP_HARD_CLEAR_TOGGLE) {
 		ep->ep_state &= ~EP_HARD_CLEAR_TOGGLE;
 		spin_unlock_irqrestore(&xhci->lock, flags);