On Sat, Sep 28, 2013 at 5:17 PM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Sat, 28 Sep 2013, Markus Rechberger wrote: > >> How about the initial patch, is it okay so far? > > I haven't had time to look through it yet. > >> There's a settopbox manufacturer who pushed it to his next firmware >> release so we can do some additional performance measuring as well. >> My next step would be to eliminate the kmallocs/kfrees for the single >> urbs (just by allocating the urbs with the same mechanism and passing >> the returned pointer to SUBMIT_URB). > > The time spent allocating and freeing URBs is probably pretty small. > pre-allocating should at least solve those issues: http://support.sundtek.com/index.php/topic,1097.msg7780.html#msg7780 but now when looking closer SG support can disable the support for shared memory support for bulk transfers. It should be possible to turn off SG Support in favor of pre-allocating the buffers (or preallocate the buffers for SG). This problem happened several times on Sheevaplug ARM systems from Marvell. Markus > 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
