On Tue, Feb 15, 2022 at 2:56 PM Mauricio Vásquez Bernal <mauricio@xxxxxxxxxx> wrote: > > On Fri, Feb 11, 2022 at 7:42 PM Andrii Nakryiko > <andrii.nakryiko@xxxxxxxxx> wrote: > > > > On Wed, Feb 9, 2022 at 2:27 PM Mauricio Vásquez <mauricio@xxxxxxxxxx> wrote: > > > > > > From: Rafael David Tinoco <rafaeldtinoco@xxxxxxxxx> > > > > > > Add "min_core_btf" feature explanation and one example of how to use it > > > to bpftool-gen man page. > > > > > > Signed-off-by: Mauricio Vásquez <mauricio@xxxxxxxxxx> > > > Signed-off-by: Rafael David Tinoco <rafael.tinoco@xxxxxxxxxxx> > > > Signed-off-by: Lorenzo Fontana <lorenzo.fontana@xxxxxxxxxx> > > > Signed-off-by: Leonardo Di Donato <leonardo.didonato@xxxxxxxxxx> > > > --- > > > .../bpf/bpftool/Documentation/bpftool-gen.rst | 93 +++++++++++++++++++ > > > 1 file changed, 93 insertions(+) > > > > > > > [...] > > > > > +Now, the "5.4.0-smaller.btf" file may be used by libbpf as an external BTF file > > > +when loading the "one.bpf.o" object into the "5.4.0-example" kernel. Note that > > > +the generated BTF file won't allow other eBPF objects to be loaded, just the > > > +ones given to min_core_btf. > > > + > > > +:: > > > + > > > + struct bpf_object *obj = NULL; > > > + struct bpf_object_open_opts openopts = {}; > > > + > > > + openopts.sz = sizeof(struct bpf_object_open_opts); > > > + openopts.btf_custom_path = "./5.4.0-smaller.btf"; > > > + > > > + obj = bpf_object__open_file("./one.bpf.o", &openopts); > > > > Can you please use LIBBPF_OPTS() macro in the example, that's how > > users are normally expected to use OPTS-based APIs anyways. Also there > > is no need for "./" when specifying file location. This is a different > > case than running a binary in the shell, where binary is searched in > > PATH. This is never done when opening files. > > > > So all this should be: > > > > LIBBPF_OPTS(bpf_object_open_opts, opts, .btf_custom_path = "5.4.0-smaller.btf"); > > struct bpf_object *obj; > > > > I suppose you meant DECLARE_LIBBPF_OPTS(...) No, actually, we do have LIBBPF_OPTS and DECLARE_LIBBPF_OPTS is just an (logically) deprecated alias to LIBBPF_OPTS. Minor difference, but shorter LIBBPF_OPTS is easier to remember. > > > obj = bpf_object__open_file("one.bpf.o", &opts); > > > > That's all. > > > > > > > + > > > + ... > > > -- > > > 2.25.1 > > >