On Fri, Dec 22, 2023 at 09:55:09AM +0000, Alan Maguire wrote: > On 21/12/2023 18:07, Alexei Starovoitov wrote: > > On Thu, Dec 21, 2023 at 9:43 AM Alan Maguire <alan.maguire@xxxxxxxxxx> wrote: > >> > >> On 21/12/2023 17:05, Alexei Starovoitov wrote: > >>> On Thu, Dec 21, 2023 at 12:35 AM Jiri Olsa <olsajiri@xxxxxxxxx> wrote: > >>>> you need to pick up only 'BTF_ID(func, ...)' IDs that belongs to SET8 lists, > >>>> which are bounded by __BTF_ID__set8__<name> symbols, which also provide size > >>> > >>> +1 > >>> > >>>>> > >>>>> Maybe we need a codemod from: > >>>>> > >>>>> BTF_ID(func, ... > >>>>> > >>>>> to: > >>>>> > >>>>> BTF_ID(kfunc, ... > >>>> > >>>> I think it's better to keep just 'func' and not to do anything special for > >>>> kfuncs in resolve_btfids logic to keep it simple > >>>> > >>>> also it's going to be already in pahole so if we want to make a fix in future > >>>> you need to change pahole, resolve_btfids and possibly also kernel > >>> > >>> I still don't understand why you guys want to add it to vmlinux BTF. > >>> The kernel has no use in this additional data. > >>> It already knows about all kfuncs. > >>> This extra memory is a waste of space from kernel pov. > >>> Unless I am missing something. > >>> > >>> imo this logic belongs in bpftool only. > >>> It can dump vmlinux BTF and emit __ksym protos into vmlinux.h > >>> > >> > >> If the goal is to have bpftool detect all kfuncs, would having a BPF > >> kfunc iterator that bpftool could use to iterate over registered kfuncs > >> work perhaps? > > > > The kernel code ? Why ? > > bpftool can do the same thing as this patch. Iterate over set8 in vmlinux elf. > > Most distros don't have the vmlinux binary easily available; it needs to > be either downloaded as part of debuginfo packages or uncompressed from > vmlinuz. would reading the /proc/kcore be an option? I'm under impression it's default for distros but I might be wrong jirka
