From 0c74d232578b1a7071e0312312811cb75b26b202 Mon Sep 17 00:00:00 2001 From: Mathias Nyman Date: Tue, 11 Mar 2025 17:45:49 +0200 Subject: [PATCH] xhci: Avoid queuing redundant Stop Endpoint command for stalled endpoint 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 Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20250311154551.4035726-2-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) 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); -- 2.50.1