On Mon, 26 Jan 2009 Saito.Koichiro@xxxxxxxxx wrote: > When testing in my environment, total retry times was 32ms. > In my environment, interval of retrying was 125us. Is this difference > different of cpu? (my testing cpu is Pentium 4 3.4GHz) Yes, that is probably the reason. My CPU is slower than yours. > I'm anxious whether this overhead affect other process. > I am sorry, I don't know in limited knowledge whether this overhead is > within acceptable. If you know that this overhead isn't problem, > please tell me reason. I don't know. And I'm starting to think that we don't need to retry for such a long time -- persistent errors should be handled by the higher-level drivers. Perhaps a count of 32 or so would be enough. > >There were a few other changes, some stylistic and some functional. > >We could consider merging this -- except that of course Dave has to > >review it. An important special case to think about: What happens if > >the device isn't running at high speed? > When I unload ehci_hcd module, I repeated whether XactErr > occurred for about one hour. But the error didn't occur. > In other speed, I don't know what have an impact. You did not understand my question. What happens if ehci_hcd is _loaded_ and the device is running at full speed or low speed because it is a USB-1.1 device plugged into a high-speed hub? Alan Stern -- 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
