On Tue, Jul 21, 2020 at 11:46 PM Andrii Nakryiko <andriin@xxxxxx> wrote: > > Following cgroup and netns examples, implement bpf_link support for XDP. > > The semantics is described in patch #2. Program and link attachments are > mutually exclusive, in the sense that neither link can replace attached > program nor program can replace attached link. Link can't replace attached > link as well, as is the case for any other bpf_link implementation. > > Patch #1 refactors existing BPF program-based attachment API and centralizes > high-level query/attach decisions in generic kernel code, while drivers are > kept simple and are instructed with low-level decisions about attaching and > detaching specific bpf_prog. This also makes QUERY command unnecessary, and > patch #8 removes support for it from all kernel drivers. If that's a bad idea, > we can drop that patch altogether. > > With refactoring in patch #1, adding bpf_xdp_link is completely transparent to > drivers, they are still functioning at the level of "effective" bpf_prog, that > should be called in XDP data path. > > Corresponding libbpf support for BPF XDP link is added in patch #5. > > v3->v4: > - fix a compilation warning in one of drivers (Jakub); As far as I could review everything looks fine, so I've applied the set. The code is delicate. I wish people were more active doing code reviews. So I encourage folks to still look at it. If there is anything missing I'm sure Andrii will fix it up in the follow up.
