From 214ac7a0771d95d2f66d01bca5afeb2c9e8ac3c8 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Fri, 22 Mar 2013 13:31:58 -0400 Subject: USB: EHCI: improve end_unlink_async() This patch (as1665) changes the way ehci-hcd's end_unlink_async() routine works in order to avoid recursive execution and to be more efficient: Now when an IAA cycle ends, a new one gets started up right away (if it is needed) instead of waiting until the just-unlinked QH has been processed. The async_iaa list is renamed to async_idle, which better expresses its new purpose: It is now the list of QHs which are now completely idle and are waiting to be processed by end_unlink_async(). A new flag is added to track whether an IAA cycle is in progress, because the list formerly known as async_iaa no longer stores the QHs waiting for the IAA to finish. The decision about how many QHs to process when an IAA cycle ends is now made at the end of the cycle, when we know the current state of the hardware, rather than at the beginning. This means a bunch of logic got moved from start_iaa_cycle() to end_unlink_async(). Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/usb/host/ehci-timer.c') diff --git a/drivers/usb/host/ehci-timer.c b/drivers/usb/host/ehci-timer.c index f63a983..11e5b32 100644 --- a/drivers/usb/host/ehci-timer.c +++ b/drivers/usb/host/ehci-timer.c @@ -304,7 +304,7 @@ static void ehci_iaa_watchdog(struct ehci_hcd *ehci) * (a) SMP races against real IAA firing and retriggering, and * (b) clean HC shutdown, when IAA watchdog was pending. */ - if (ehci->rh_state != EHCI_RH_RUNNING) + if (!ehci->iaa_in_progress || ehci->rh_state != EHCI_RH_RUNNING) return; /* If we get here, IAA is *REALLY* late. It's barely -- cgit v1.1