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.
+{
+ 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;
}
[...]
