libbpf: Add enum64 deduplication support

Add enum64 deduplication support. BTF_KIND_ENUM64 handling
is very similar to BTF_KIND_ENUM.

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220607062626.3720166-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Yonghong Song 2022-06-06 23:26:26 -07:00 committed by Alexei Starovoitov
parent dffbbdc2d9
commit 2ef2026349
2 changed files with 65 additions and 2 deletions

View file

@ -3582,7 +3582,7 @@ static bool btf_equal_int_tag(struct btf_type *t1, struct btf_type *t2)
return info1 == info2;
}
/* Calculate type signature hash of ENUM. */
/* Calculate type signature hash of ENUM/ENUM64. */
static long btf_hash_enum(struct btf_type *t)
{
long h;
@ -3616,9 +3616,31 @@ static bool btf_equal_enum(struct btf_type *t1, struct btf_type *t2)
return true;
}
static bool btf_equal_enum64(struct btf_type *t1, struct btf_type *t2)
{
const struct btf_enum64 *m1, *m2;
__u16 vlen;
int i;
if (!btf_equal_common(t1, t2))
return false;
vlen = btf_vlen(t1);
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;
}
static inline bool btf_is_enum_fwd(struct btf_type *t)
{
return btf_is_enum(t) && btf_vlen(t) == 0;
return btf_is_any_enum(t) && btf_vlen(t) == 0;
}
static bool btf_compat_enum(struct btf_type *t1, struct btf_type *t2)
@ -3631,6 +3653,17 @@ static bool btf_compat_enum(struct btf_type *t1, struct btf_type *t2)
t1->size == t2->size;
}
static bool btf_compat_enum64(struct btf_type *t1, struct btf_type *t2)
{
if (!btf_is_enum_fwd(t1) && !btf_is_enum_fwd(t2))
return btf_equal_enum64(t1, t2);
/* ignore vlen when comparing */
return t1->name_off == t2->name_off &&
(t1->info & ~0xffff) == (t2->info & ~0xffff) &&
t1->size == t2->size;
}
/*
* Calculate type signature hash of STRUCT/UNION, ignoring referenced type IDs,
* as referenced type IDs equivalence is established separately during type
@ -3843,6 +3876,7 @@ static int btf_dedup_prep(struct btf_dedup *d)
h = btf_hash_int_decl_tag(t);
break;
case BTF_KIND_ENUM:
case BTF_KIND_ENUM64:
h = btf_hash_enum(t);
break;
case BTF_KIND_STRUCT:
@ -3932,6 +3966,27 @@ static int btf_dedup_prim_type(struct btf_dedup *d, __u32 type_id)
}
break;
case BTF_KIND_ENUM64:
h = btf_hash_enum(t);
for_each_dedup_cand(d, hash_entry, h) {
cand_id = (__u32)(long)hash_entry->value;
cand = btf_type_by_id(d->btf, cand_id);
if (btf_equal_enum64(t, cand)) {
new_id = cand_id;
break;
}
if (btf_compat_enum64(t, cand)) {
if (btf_is_enum_fwd(t)) {
/* resolve fwd to full enum */
new_id = cand_id;
break;
}
/* resolve canonical enum fwd to full enum */
d->map[cand_id] = type_id;
}
}
break;
case BTF_KIND_FWD:
case BTF_KIND_FLOAT:
h = btf_hash_common(t);
@ -4227,6 +4282,9 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
case BTF_KIND_ENUM:
return btf_compat_enum(cand_type, canon_type);
case BTF_KIND_ENUM64:
return btf_compat_enum64(cand_type, canon_type);
case BTF_KIND_FWD:
case BTF_KIND_FLOAT:
return btf_equal_common(cand_type, canon_type);

View file

@ -531,6 +531,11 @@ static inline bool btf_is_type_tag(const struct btf_type *t)
return btf_kind(t) == BTF_KIND_TYPE_TAG;
}
static inline bool btf_is_any_enum(const struct btf_type *t)
{
return btf_is_enum(t) || btf_is_enum64(t);
}
static inline __u8 btf_int_encoding(const struct btf_type *t)
{
return BTF_INT_ENCODING(*(__u32 *)(t + 1));