On Sat, Jan 13, 2024 at 09:17:44AM -0700, Daniel Xu wrote: > Hi Jiri, > > On Sat, Jan 13, 2024 at 02:57:40PM +0100, Jiri Olsa wrote: > > On Fri, Jan 12, 2024 at 01:03:59PM -0700, Daniel Xu wrote: > > > On Fri, Jan 12, 2024 at 05:20:39PM +0100, Jiri Olsa wrote: > > > > On Sat, Jan 06, 2024 at 11:24:07AM -0700, Daniel Xu wrote: > > > > > === Description === > > > > > > > > > > This is a bpf-treewide change that annotates all kfuncs as such inside > > > > > .BTF_ids. This annotation eventually allows us to automatically generate > > > > > kfunc prototypes from bpftool. > > > > > > > > > > We store this metadata inside a yet-unused flags field inside struct > > > > > btf_id_set8 (thanks Kumar!). pahole will be taught where to look. > > > > > > > > > > More details about the full chain of events are available in commit 3's > > > > > description. > > > > > > > > > > The accompanying pahole changes (still needs some cleanup) can be viewed > > > > > here on this "frozen" branch [0]. > > > > > > > > so the plan is to have bpftool support to generate header file > > > > with detected kfuncs? > > > > > > Yep, that's the major use case. But I see other use cases as well like > > > > ok, any chance you could already include it in the patchset? > > would be a great way to test this.. maybe we could change > > selftests to use that > > I haven't start working on that code yet, but I can. > > Here is my plan FWIW: > > 1. Bump minimum required pahole version up. Or feature probe for > kfunc decl tag support. Whatever is the standard practice here. > > 2. Teach bpftool to dump kfunc prototypes, guarded behind a flag. > > 3. Flip bpftool flag on in selftest build and remove all manual kfunc > prototypes atomically in 1 commit. > > I thought it'd be nicer to do it incrementally given all the moving > pieces. But if we want to land it all at once that is ok by me too. I think it'd be best to try the whole thing before we merge the change to pahole.. I guess the tests changes can come later, but would be great to try the kfunc dump and make sure it works as expected jirka
