On Mon, Sep 2, 2024 at 9:22 AM Daniel Borkmann <daniel@xxxxxxxxxxxxx> wrote:
>
> On 9/1/24 11:30 PM, "Mykyta Yatsenko mykyta.yatsenko5"@gmail.com wrote:
> > From: Mykyta Yatsenko <yatsenko@xxxxxxxx>
> >
> > Wrong function is used to access the first enum64 element.
> > Substituting btf_enum(t) with btf_enum64(t) for BTF_KIND_ENUM64.
> >
> > Signed-off-by: Mykyta Yatsenko <yatsenko@xxxxxxxx>
> > ---
> > tools/bpf/bpftool/btf.c | 13 ++++++++++---
> > 1 file changed, 10 insertions(+), 3 deletions(-)
> >
> > diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c
> > index 6789c7a4d5ca..b0f12c511bb3 100644
> > --- a/tools/bpf/bpftool/btf.c
> > +++ b/tools/bpf/bpftool/btf.c
> > @@ -557,16 +557,23 @@ static const char *btf_type_sort_name(const struct btf *btf, __u32 index, bool f
> > const struct btf_type *t = btf__type_by_id(btf, index);
> >
> > switch (btf_kind(t)) {
> > - case BTF_KIND_ENUM:
> > - case BTF_KIND_ENUM64: {
> > + case BTF_KIND_ENUM: {
> > int name_off = t->name_off;
> >
> > /* Use name of the first element for anonymous enums if allowed */
> > - if (!from_ref && !t->name_off && btf_vlen(t))
> > + if (!from_ref && !name_off && btf_vlen(t))
> > name_off = btf_enum(t)->name_off;
> >
> > return btf__name_by_offset(btf, name_off);
> > }
>
> Small nit, could we consolidate the logic into the below? Still somewhat nicer
> than duplicating all of the rest.
>
> diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c
> index 6789c7a4d5ca..aae6f5262c6a 100644
> --- a/tools/bpf/bpftool/btf.c
> +++ b/tools/bpf/bpftool/btf.c
> @@ -562,8 +562,10 @@ static const char *btf_type_sort_name(const struct btf *btf, __u32 index, bool f
> int name_off = t->name_off;
>
> /* Use name of the first element for anonymous enums if allowed */
> - if (!from_ref && !t->name_off && btf_vlen(t))
> - name_off = btf_enum(t)->name_off;
> + if (!from_ref && !name_off && btf_vlen(t))
> + name_off = btf_kind(t) == BTF_KIND_ENUM64 ?
Just fyi for the future (I don't think we need to fix this or anything
like that), but using BTF_KIND_xxx constants in btf_kind(t)
comparisons should be rare. Libbpf provides a full set of shorter
btf_is_xxx(t) helpers for this. So this would be just
`btf_is_enum64(t)`. What you did is not wrong, it's just more
open-coded and verbose.
> + btf_enum64(t)->name_off :
> + btf_enum(t)->name_off;
>
> return btf__name_by_offset(btf, name_off);
> }
>
> Thanks,
> Daniel
