[Cake] profiling using perf

[Georgios Amanakis]

Dear List,

I made an effort to profile the performance of cake with perf in
openwrt. perf was run on a WRT1900ACS router while downloading
archlinux.iso via torrent in a LAN client. You can find the annotated
sch_cake.c in the attachment as well as a performance histogram of
sch_cake (percentages are relative to sch_cake).

Hopefully people can take a look at it, and see if there are
performance concerns. As far as I can tell