I think that licence is not the only problem here. The way some things were implemented within Linux kernel are making things how they are today. I mean DTrace

I think that licence is not the only problem here. The way some things were implemented within Linux kernel are making things how they are today. I mean DTrace could be ported to Linux, maybe, I don't know, but best thing to do would be to reach Bryan Cantrill and ask him, I think he would give you pretty reasonable answer. He spoke about some things on BSD Now podcast.