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by tptacek 1657 days ago
Bounded loops are 5.3. I'm just saying that after like 9 months of development following their introduction, it remained tricky to get the verifier to accept loops with seemingly obvious bounds. I know the feature works (I did ultimately get some loops working!) but I could not have straightforwardly ported userland C code to do it.

You've always been able to unroll loops, but of course you're chewing up code space doing that.

I don't know what BPF_TABLE is (I think it's a BCC-ism?) but BPF hash maps can take 16 byte keys. But notice that you're now writing something that looks nothing at all like Node's HTTP parser.

I'm not doubting that they did this work. I just want to know what it ends up looking like!

1 comments

Oh nice, we haven't tried bounded loop, because our product is committed to support as old as 4.13.

BPF_TABLE is BCC.