I quickly got sch_cake to work on top of net next. The attached diff
is probably not correct in some respect or another (what's to_free
for? And it looks like statistics collection has been parallelized
elsewhere)

... but I did not crash my box in an hour of trying, with it.

Judging from me tearing apart how TCP BBR works (presently) with ecn,
it looks like we need to add the equivalent to fq_codel ce_threshold
behaviors as well.

https://raw.githubusercontent.com/dtaht/blog-cerowrt/11cabc4c75358c075d4cab770377c986442282ec/content/flent/bbr-cethresh/think_cake_needs_ce_threshold.png



-- 
Dave Täht
Let's go make home routers and wifi faster! With better software!
http://blog.cerowrt.org