On Mon, Jul 29, 2013 at 9:41 PM, James Stone <jamesmstone@xxxxxxxxx> wrote: > On Mon, Jul 29, 2013 at 4:25 PM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: >> On Sun, 28 Jul 2013, James Stone wrote: >> >>> On Sat, Jul 27, 2013 at 6:45 PM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: >>> > On Sat, 27 Jul 2013, James Stone wrote: >>> > >>> >> OK. So this seems to have solved the starting jack at low latencies >>> >> problem, but I am still getting sporadic cannot submit urb (err = -18) >>> >> under normal use. Will try to add some more info to the #1191603 >>> >> report if I can get it to happen while logging IRQ. >>> > >>> > Do these errors occur at the start of a session or somewhere in the >>> > middle? >>> > >>> > If they occur in the middle, they indicate possible underruns. The >>> > patch below will greatly reduce the number of these errors (probably to >>> > the point where you don't see any at all), although it won't fix >>> > possible underruns. >>> > >>> >>> OK - this patch didn't help - still seeing these cannot submit urb >>> (err = -18) errors coming up at random times (this time while the >>> computer was idling). >> >> Do you think you can get a usbmon trace showing one of those errors? >> Or would the trace file end up being hopelessly large? >> > > No - no way to get usbmon trace on this - it happens only every few > hours at unpredictable times, and I can't work out what triggers it. > > J OK, having said that, I just got it to happen - listening to audacity and just logging into Facebook (of all things!! Meh!) This is the contents of the trace file (as per instructions on bug #1191603) # tracer: irqsoff # # irqsoff latency trace v1.1.5 on 3.10.0-ver5 # -------------------------------------------------------------------- # latency: 2173 us, #4/4, CPU#0 | (M:desktop VP:0, KP:0, SP:0 HP:0 #P:4) # ----------------- # | task: apt-check-3628 (uid:1000 nice:19 policy:0 rt_prio:0) # ----------------- # => started at: perf_event_update_userpage # => ended at: retint_careful # # # _------=> CPU# # / _-----=> irqs-off # | / _----=> need-resched # || / _---=> hardirq/softirq # ||| / _--=> preempt-depth # |||| / delay # cmd pid ||||| time | caller # \ / ||||| \ | / apt-chec-3628 0d.h. 0us!: local_clock <-perf_event_update_userpage apt-chec-3628 0dN.. 2173us : trace_hardirqs_on_thunk <-retint_careful apt-chec-3628 0dN.. 2173us+: trace_hardirqs_on_caller <-retint_careful apt-chec-3628 0dN.. 2177us : <stack trace> => trace_hardirqs_on_thunk I will send the tail of the usbmon trace off-list. James -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
