On Wed, 21 Jul 2004, Oliver Neukum wrote: > > It's unclear to me to what extent all these things really need to be > > allocated beforehand, however. Certainly for things like usb-storage it > > makes sense to do this with buffers involved in actual data transfers, to > > minimize latency if nothing else. But for subsidiary usages, like the > > URBs and buffers used in doing a reset? These are pretty rare and not > > especially time-critical, although they do need to use GFP_NOIO. > > We want only one method of URB allocation, don't we?
Of course. But that method could be used either to pre-allocate URBs and buffers like Matt is suggesting, or to allocate them on demand like we do now. > > I'm puzzled how pre-allocation would help usb_kill_urb(). > > Reentrancy. The URB can be resubmitted from the completion handler, but > it cannot have completed. I don't see what this has to do with pre-allocating URBs. (Also I don't understand what you mean "it cannot have completed", but maybe that's not important for this discussion.) Alan Stern ------------------------------------------------------- This SF.Net email is sponsored by BEA Weblogic Workshop FREE Java Enterprise J2EE developer tools! Get your free copy of BEA WebLogic Workshop 8.1 today. http://ads.osdn.com/?ad_id=4721&alloc_id=10040&op=click _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
