On Thu, 28 Mar 2019 at 10:48, Maxim Mikityanskiy <maxi...@mellanox.com> wrote: > [...] > > > Thanks for the good input, Max! The rationale for making the sample > > > simpler, was that most people was just C&Ping from it and used it in > > > their own code, so we aimed for a simple "fits-most-people" sample. > > I don't think it's easier for them to use binaries in their own code > than proper sources. Having the XDP program built from sources in libbpf > doesn't complicate the sample in any way, though. >
Correct, but then Clang would be a libbpf build dependency. Maybe that's ok? If that is added, I'd be happy do remove the raw BPF instructions. Personally, I don't have a hard time reading a couple of lines of assembly, but I see your point and agree. Having it as C-code would be better for the libbpf developers -- if the Clang build dependency is ok. > > > Let's make an "advanced user" sample as well, and add shared umem > > > support to libbpf! > > Why create another sample if we have this one? Actually, how making > another sample fixes this one? The issue is in libbpf anyway. It has a > blob inside with no tools to regenerate it from C sources. And this lib > is not even a sample, it can be used by real applications. Of course, it > should be editable, otherwise no new feature can be added (without > manually writing bytecode), and it's not the matter of shared UMEM. > Magnus and I took the route to simplify the sample, to make it easier for new users. I still think that was the right path. Should there be a sample showcasing all the knobs/pulleys? Sure. > > > ...and as always, patches are very much welcome! > > Good approach - to drop a feature and wait until someone submits a patch > to restore it. And how do you imagine that patch that adds back shared > UMEM? The blob in libbpf has to be edited to accomplish this. It makes > unnecessary trouble for anyone trying to contribute. > I appreciate that you are looking into the code/design with constructive remarks -- but please refrain from being snarky. Björn
