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.
