On Tue, May 17, 2022 at 10:11 AM Yonghong Song <yhs@xxxxxx> wrote:
>
>
>
> On 5/16/22 5:28 PM, Andrii Nakryiko wrote:
> > On Fri, May 13, 2022 at 8:13 PM Yonghong Song <yhs@xxxxxx> wrote:
> >>
> >> Add enum64 deduplication support. BTF_KIND_ENUM64 handling
> >> is very similar to BTF_KIND_ENUM.
> >>
> >> Signed-off-by: Yonghong Song <yhs@xxxxxx>
> >> ---
> >> tools/lib/bpf/btf.c | 55 +++++++++++++++++++++++++++++++++------------
> >> tools/lib/bpf/btf.h | 5 +++++
> >> 2 files changed, 46 insertions(+), 14 deletions(-)
> >>
> >
> > [...]
> >
> >> +static bool btf_equal_enum64_val(struct btf_type *t1, struct btf_type *t2)
> >> +{
> >> + const struct btf_enum64 *m1, *m2;
> >> + __u16 vlen = btf_vlen(t1);
> >> + int i;
> >> +
> >> + m1 = btf_enum64(t1);
> >> + m2 = btf_enum64(t2);
> >> + for (i = 0; i < vlen; i++) {
> >> + if (m1->name_off != m2->name_off || m1->val_lo32 != m2->val_lo32 ||
> >> + m1->val_hi32 != m2->val_hi32)
> >> + return false;
> >> + m1++;
> >> + m2++;
> >> + }
> >> + return true;
> >> +}
> >> +
> >> +/* Check structural equality of two ENUMs. */
> >> +static bool btf_equal_enum_or_enum64(struct btf_type *t1, struct btf_type *t2)
> >
> > I find this helper quite confusing. It implies it can compare any enum
> > or enum64 with each other, but it really allows only enum vs enum and
> > enum64 vs enum64 (as it should!). Let's keep
> > btf_equal_enum()/btf_compat_enum() completely intact and add
> > btf_equal_enum64()/btf_compat_enum64() separately (few lines of
> > copy-pasted code is totally fine to keep them separate, IMO). See
> > below.
>
> I debate with myself about whether I should use separate functions or
> use one function for both enum/enum64. My current approach will have
> less code changes. But I can do what you suggested to have separate
> functions for enum and enum64. This will apply to btf_compat_enum
> as well.
yep, thanks!
>
> >
> >> +{
> >> + if (!btf_equal_common(t1, t2))
> >> + return false;
> >> +
> >> + if (btf_is_enum(t1))
> >> + return btf_equal_enum32_val(t1, t2);
> >> + return btf_equal_enum64_val(t1, t2);
> >> +}
> >> +
> >> static inline bool btf_is_enum_fwd(struct btf_type *t)
> >> {
> >> - return btf_is_enum(t) && btf_vlen(t) == 0;
> >> + return btf_type_is_any_enum(t) && btf_vlen(t) == 0;
> >> }
> >>
> [...]
