On Wed, Nov 11, 2020 at 10:34 AM Arnaldo <arnaldo.melo@xxxxxxxxx> wrote: > > > > On November 11, 2020 3:27:58 PM GMT-03:00, Andrii Nakryiko <andrii.nakryiko@xxxxxxxxx> wrote: > >On Wed, Nov 11, 2020 at 3:56 AM Arnaldo Carvalho de Melo > ><acme@xxxxxxxxxx> wrote: > >> > >> Em Thu, Nov 05, 2020 at 09:25:49PM -0800, Andrii Nakryiko escreveu: > >> > Add support for generating split BTF, in which there is a > >designated base > >> > BTF, containing a base set of types, and a split BTF, which extends > >main BTF > >> > with extra types, that can reference types and strings from the > >main BTF. > >> > >> > This is going to be used to generate compact BTFs for kernel > >modules, with > >> > vmlinux BTF being a main BTF, which all kernel modules are based > >off of. > >> > >> > These changes rely on patch set [0] to be present in libbpf > >submodule. > >> > >> > [0] > >https://patchwork.kernel.org/project/netdevbpf/list/?series=377859&state=* > >> > >> So, applied and added this: > > > >Awesome, thanks! Do you plan to release v1.19 soon? > > Yes > > > > >> > >> diff --git a/man-pages/pahole.1 b/man-pages/pahole.1 > >> index 4b5e0a1bf5462b28..20ee91fc911d4b39 100644 > >> --- a/man-pages/pahole.1 > >> +++ b/man-pages/pahole.1 > >> @@ -185,6 +185,10 @@ Do not encode VARs in BTF. > >> .B \-\-btf_encode_force > >> Ignore those symbols found invalid when encoding BTF. > >> > >> +.TP > >> +.B \-\-btf_base > >> +Path to the base BTF file, for instance: vmlinux when encoding > >kernel module BTF information. > >> + > >> .TP > >> .B \-l, \-\-show_first_biggest_size_base_type_member > >> Show first biggest size base_type member. > >> > >> --------------- > >> > >> The entry for btf_encode/-J is missing, I'll add in a followup patch. > >> > >> Also I had to fixup ARGP_btf_base to 321 as I added this, to simplify > >> the kernel scripts and Makefiles: > >> > >> $ pahole --numeric_version > >> 118 > >> $ > > > >Oh, this is nice! Can't really use it with Kbuild now due to backwards > >compatibility, but maybe someday. > > Well, if it fails with --numeric_version, then it is old and the warning about the minimal version being v1.19 should be emitted :) Right, but for CONFIG_DEBUG_INFO_BTF v1.13 is still adequate enough and will generates useful BTF (no functions and no module BTF, but all the CO-RE stuff is there), I wouldn't want to force everyone to get v1.19 immediately... > > - Arnaldo > > > >> > >> Now to test this all by applying the kernel patches and the encoding > >> module BTF, looking at it, etc. > >> > >> - Arnaldo > >> > > > >[...] > > -- > Sent from my Android device with K-9 Mail. Please excuse my brevity.
