On Thu, Oct 31, 2013 at 2:25 PM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Thu, 31 Oct 2013, Cliff Brake wrote: > >> On Thu, Oct 31, 2013 at 1:54 PM, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: >> >> > Ick, that's not good. This sounds like a driver issue, if you can find >> > out where interrupts are being held for so long, hopefully a fix can be >> > found and resolved. It's good that 3.11 is better, but ideally a real >> > fix can be created. >> > >> > What host controller driver are you using? >> >> Its the USB EHCI host in the TI DM3730, so it uses the >> drivers/usb/host/ehci-omap.c driver. > > You can find out exactly what part of the kernel is responsible for > interrupt delays by using the "irqsoff" tracer. See > Documentation/trace/ftrace.txt for details about how to use it. Thanks, I'll try to get some data on that. Its interesting that we've not observed problems with any other USB devices (network, mass storage, etc). Cliff -- ================= http://bec-systems.com -- 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
