map_queue will always return 0 in the pfifo_fast Qdisc. This is because
pfifo_fast is the default scheduler when a device is brought up. I
didn't want to make any assumptions about a device's functionality, so
using queue 0 seems the least dangerous.
However, in the prio qdisc, there is a small problem with the queue to
band assignment logic. If you have the same number of bands as queues
(e.g. 4 prio bands and 4 Tx queues), then you will have all bands
assigned to queue 0. I have a fix for that, which I plan to send when I
finish up a documentation piece for this patch's repost.
Thanks for the feedback,