On Sat, Mar 27, 2021 at 04:17:16PM +0100, Toke Høiland-Jørgensen wrote: > Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx> writes: > > > On Thu, Mar 25, 2021 at 05:30:03PM +0530, Kumar Kartikeya Dwivedi wrote: > >> This adds some basic tests for the low level bpf_tc_* API and its > >> bpf_program__attach_tc_* wrapper on top. > > > > *_block() apis from patch 3 and 4 are not covered by this selftest. > > Why were they added ? And how were they tested? > > > > Pls trim your cc. bpf@vger and netdev@vger would have been enough. > > > > My main concern with this set is that it adds netlink apis to libbpf while > > we already agreed to split xdp manipulation pieces out of libbpf. > > It would be odd to add tc apis now only to split them later. > > We're not removing the ability to attach an XDP program via netlink from > libxdp, though. This is the equivalent for TC: the minimum support to > attach a program, and if you want to do more, you pull in another > library or roll your own. > > I'm fine with cutting out more stuff and making this even more minimal > (e.g., remove the block stuff and only support attach/detach on ifaces), > but we figured we'd err on the side of including too much and getting > some feedback from others on which bits are the essential ones to keep, > and which can be dropped. This is up to you. I'm trying to understand the motivation for *_block() apis. I'm not taking a stance for/against them. > > I think it's better to start with new library for tc/xdp and have > > libbpf as a dependency on that new lib. > > For example we can add it as subdir in tools/lib/bpf/. > > I agree for the higher-level stuff (though I'm not sure what that would > be for TC), but right now TC programs are the only ones that cannot be > attached by libbpf, which is annoying; that's what we're trying to fix. Sure. I wasn't saying that there is no place for these APIs in libbpf+. Just that existing libbpf is already became a kitchen sink of features that users are not going to use like static linking. tc-api was a straw that broke the camel's back. I think we must move static linking and skeleton out of libbpf before the next release.
