From 056761e55c8687ddf3db14226213f2e8dc2689bc Mon Sep 17 00:00:00 2001 From: David Brownell Date: Fri, 13 Jun 2008 23:56:48 -0700 Subject: [PATCH] USB: ehci - fix timer regression This patch fixes a regression in the EHCI driver's TIMER_IO_WATCHDOG behavior. The patch "USB: EHCI: add separate IAA watchdog timer" changed how that timer is handled, so that short timeouts on the remaining timer (unfortunately, overloaded) would never be used. This takes a more direct approach, reorganizing the code slightly to be explicit about only the I/O watchdog role now being overridable. It also replaces a now-obsolete comment describing older timer behavior. Signed-off-by: David Brownell Cc: Alan Stern Cc: Leonid Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci.h | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h index 35a03095757..90245fd8bac 100644 --- a/drivers/usb/host/ehci.h +++ b/drivers/usb/host/ehci.h @@ -177,6 +177,15 @@ timer_action_done (struct ehci_hcd *ehci, enum ehci_timer_action action) static inline void timer_action (struct ehci_hcd *ehci, enum ehci_timer_action action) { + /* Don't override timeouts which shrink or (later) disable + * the async ring; just the I/O watchdog. Note that if a + * SHRINK were pending, OFF would never be requested. + */ + if (timer_pending(&ehci->watchdog) + && ((BIT(TIMER_ASYNC_SHRINK) | BIT(TIMER_ASYNC_OFF)) + & ehci->actions)) + return; + if (!test_and_set_bit (action, &ehci->actions)) { unsigned long t; @@ -192,15 +201,7 @@ timer_action (struct ehci_hcd *ehci, enum ehci_timer_action action) t = EHCI_SHRINK_JIFFIES; break; } - t += jiffies; - // all timings except IAA watchdog can be overridden. - // async queue SHRINK often precedes IAA. while it's ready - // to go OFF neither can matter, and afterwards the IO - // watchdog stops unless there's still periodic traffic. - if (time_before_eq(t, ehci->watchdog.expires) - && timer_pending (&ehci->watchdog)) - return; - mod_timer (&ehci->watchdog, t); + mod_timer(&ehci->watchdog, t + jiffies); } } -- 2.20.1