| Message ID | 20210907230105.1958546-1-yhs@fb.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | bpf: add support for new btf kind BTF_KIND_TAG | expand |
On Tue, Sep 7, 2021 at 4:01 PM Yonghong Song <yhs@fb.com> wrote: > > Add BTF_KIND_TAG support for parsing and dedup. > Also added sanitization for BTF_KIND_TAG. If BTF_KIND_TAG is not > supported in the kernel, sanitize it to INTs. > > Signed-off-by: Yonghong Song <yhs@fb.com> > --- > tools/lib/bpf/btf.c | 61 +++++++++++++++++++++++++++++++++ > tools/lib/bpf/btf.h | 13 +++++++ > tools/lib/bpf/btf_dump.c | 3 ++ > tools/lib/bpf/libbpf.c | 31 +++++++++++++++-- > tools/lib/bpf/libbpf.map | 1 + > tools/lib/bpf/libbpf_internal.h | 2 ++ > 6 files changed, 108 insertions(+), 3 deletions(-) > > diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c > index 7cb6ebf1be37..ed02b17aad17 100644 > --- a/tools/lib/bpf/btf.c > +++ b/tools/lib/bpf/btf.c > @@ -304,6 +304,8 @@ static int btf_type_size(const struct btf_type *t) > return base_size + sizeof(struct btf_var); > case BTF_KIND_DATASEC: > return base_size + vlen * sizeof(struct btf_var_secinfo); > + case BTF_KIND_TAG: > + return base_size + sizeof(struct btf_tag); > default: > pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t)); > return -EINVAL; > @@ -376,6 +378,9 @@ static int btf_bswap_type_rest(struct btf_type *t) > v->size = bswap_32(v->size); > } > return 0; > + case BTF_KIND_TAG: > + btf_tag(t)->comp_id = bswap_32(btf_tag(t)->comp_id); > + return 0; > default: > pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t)); > return -EINVAL; > @@ -586,6 +591,7 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id) > case BTF_KIND_CONST: > case BTF_KIND_RESTRICT: > case BTF_KIND_VAR: > + case BTF_KIND_TAG: > type_id = t->type; > break; > case BTF_KIND_ARRAY: > @@ -2440,6 +2446,41 @@ int btf__add_datasec_var_info(struct btf *btf, int var_type_id, __u32 offset, __ > return 0; > } > > +int btf__add_tag(struct btf *btf, const char *name, int comp_id, int ref_type_id) Curious about the terminology here. The string recorded in bpf_tag, is that a "name" of the tag, or rather a "value" of the tag? We should reflect that in argument names for btf__add_tag. I'll also nitpick on order of arguments. ref_type_id is always specified, and it points to the entire type (struct/union/func), while comp_id might, optionally, point inside that type. So I think the order should be ref_type_id followed by comp_id. Please also add a comment describing inputs (especially the -1 comp_id case) and outputs, like all that other btf__add_xxx() APIs. > +{ > + bool for_ref_type = false; > + struct btf_type *t; > + int sz, name_off; > + > + if (!name || !name[0] || comp_id < -1) > + return libbpf_err(-EINVAL); > + > + if (validate_type_id(ref_type_id)) > + return libbpf_err(-EINVAL); > + > + if (btf_ensure_modifiable(btf)) > + return libbpf_err(-ENOMEM); > + > + sz = sizeof(struct btf_type) + sizeof(struct btf_tag); > + t = btf_add_type_mem(btf, sz); > + if (!t) > + return libbpf_err(-ENOMEM); > + > + name_off = btf__add_str(btf, name); > + if (name_off < 0) > + return name_off; > + > + t->name_off = name_off; > + t->type = ref_type_id; > + > + if (comp_id == -1) > + for_ref_type = true; > + t->info = btf_type_info(BTF_KIND_TAG, 0, for_ref_type); > + ((struct btf_tag *)(t + 1))->comp_id = for_ref_type ? 0 : comp_id; As I mentioned in the previous patch, it feels cleaner to just have this -1 special value and not utilize kflag at all. It will match libbpf API as you defined it naturally. > + > + return btf_commit_type(btf, sz); > +} > + [...] > case BTF_KIND_ARRAY: { > diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h > index 4a711f990904..a78cf8331d49 100644 > --- a/tools/lib/bpf/btf.h > +++ b/tools/lib/bpf/btf.h > @@ -141,6 +141,9 @@ LIBBPF_API int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz > LIBBPF_API int btf__add_datasec_var_info(struct btf *btf, int var_type_id, > __u32 offset, __u32 byte_sz); > > +/* tag contruction API */ typo: construction, but I'd put it after btf__add_restrict with no comment > +LIBBPF_API int btf__add_tag(struct btf *btf, const char *name, int comp_id, int ref_type_id); > + > struct btf_dedup_opts { > unsigned int dedup_table_size; > bool dont_resolve_fwds; > @@ -328,6 +331,11 @@ static inline bool btf_is_float(const struct btf_type *t) > return btf_kind(t) == BTF_KIND_FLOAT; > } > > +static inline bool btf_is_tag(const struct btf_type *t) > +{ > + return btf_kind(t) == BTF_KIND_TAG; > +} > + > static inline __u8 btf_int_encoding(const struct btf_type *t) > { > return BTF_INT_ENCODING(*(__u32 *)(t + 1)); > @@ -396,6 +404,11 @@ btf_var_secinfos(const struct btf_type *t) > return (struct btf_var_secinfo *)(t + 1); > } > please add `struct btf_tag;` forward reference for those users who are compiling with old UAPI headers. > +static inline struct btf_tag *btf_tag(const struct btf_type *t) > +{ > + return (struct btf_tag *)(t + 1); > +} > + > #ifdef __cplusplus > } /* extern "C" */ > #endif [...] > LIBBPF_0.5.0 { > global: > + btf__add_tag; > bpf_map__initial_value; > bpf_map__pin_path; > bpf_map_lookup_and_delete_elem_flags; > diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h > index 533b0211f40a..7deb86d9af51 100644 > --- a/tools/lib/bpf/libbpf_internal.h > +++ b/tools/lib/bpf/libbpf_internal.h > @@ -69,6 +69,8 @@ > #define BTF_VAR_SECINFO_ENC(type, offset, size) (type), (offset), (size) > #define BTF_TYPE_FLOAT_ENC(name, sz) \ > BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_FLOAT, 0, 0), sz) > +#define BTF_TYPE_TAG_KIND_ENC(name, type) \ following other macro names, it should be BTF_TYPE_TAG_ENC, no? > + BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_TAG, 1, 0), type), (0) > > #ifndef likely > #define likely(x) __builtin_expect(!!(x), 1) > -- > 2.30.2 >
On 9/8/21 10:26 PM, Andrii Nakryiko wrote: > On Tue, Sep 7, 2021 at 4:01 PM Yonghong Song <yhs@fb.com> wrote: >> >> Add BTF_KIND_TAG support for parsing and dedup. >> Also added sanitization for BTF_KIND_TAG. If BTF_KIND_TAG is not >> supported in the kernel, sanitize it to INTs. >> >> Signed-off-by: Yonghong Song <yhs@fb.com> >> --- >> tools/lib/bpf/btf.c | 61 +++++++++++++++++++++++++++++++++ >> tools/lib/bpf/btf.h | 13 +++++++ >> tools/lib/bpf/btf_dump.c | 3 ++ >> tools/lib/bpf/libbpf.c | 31 +++++++++++++++-- >> tools/lib/bpf/libbpf.map | 1 + >> tools/lib/bpf/libbpf_internal.h | 2 ++ >> 6 files changed, 108 insertions(+), 3 deletions(-) >> >> diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c >> index 7cb6ebf1be37..ed02b17aad17 100644 >> --- a/tools/lib/bpf/btf.c >> +++ b/tools/lib/bpf/btf.c >> @@ -304,6 +304,8 @@ static int btf_type_size(const struct btf_type *t) >> return base_size + sizeof(struct btf_var); >> case BTF_KIND_DATASEC: >> return base_size + vlen * sizeof(struct btf_var_secinfo); >> + case BTF_KIND_TAG: >> + return base_size + sizeof(struct btf_tag); >> default: >> pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t)); >> return -EINVAL; >> @@ -376,6 +378,9 @@ static int btf_bswap_type_rest(struct btf_type *t) >> v->size = bswap_32(v->size); >> } >> return 0; >> + case BTF_KIND_TAG: >> + btf_tag(t)->comp_id = bswap_32(btf_tag(t)->comp_id); >> + return 0; >> default: >> pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t)); >> return -EINVAL; >> @@ -586,6 +591,7 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id) >> case BTF_KIND_CONST: >> case BTF_KIND_RESTRICT: >> case BTF_KIND_VAR: >> + case BTF_KIND_TAG: >> type_id = t->type; >> break; >> case BTF_KIND_ARRAY: >> @@ -2440,6 +2446,41 @@ int btf__add_datasec_var_info(struct btf *btf, int var_type_id, __u32 offset, __ >> return 0; >> } >> >> +int btf__add_tag(struct btf *btf, const char *name, int comp_id, int ref_type_id) > > Curious about the terminology here. The string recorded in bpf_tag, is > that a "name" of the tag, or rather a "value" of the tag? We should > reflect that in argument names for btf__add_tag. We can use "value" as the argument. > > I'll also nitpick on order of arguments. ref_type_id is always > specified, and it points to the entire type (struct/union/func), while > comp_id might, optionally, point inside that type. So I think the > order should be ref_type_id followed by comp_id. Will switch and then the argument order follows ELF file format order. > > Please also add a comment describing inputs (especially the -1 comp_id > case) and outputs, like all that other btf__add_xxx() APIs. Will do. > >> +{ >> + bool for_ref_type = false; >> + struct btf_type *t; >> + int sz, name_off; >> + >> + if (!name || !name[0] || comp_id < -1) >> + return libbpf_err(-EINVAL); >> + >> + if (validate_type_id(ref_type_id)) >> + return libbpf_err(-EINVAL); >> + >> + if (btf_ensure_modifiable(btf)) >> + return libbpf_err(-ENOMEM); >> + >> + sz = sizeof(struct btf_type) + sizeof(struct btf_tag); >> + t = btf_add_type_mem(btf, sz); >> + if (!t) >> + return libbpf_err(-ENOMEM); >> + >> + name_off = btf__add_str(btf, name); >> + if (name_off < 0) >> + return name_off; >> + >> + t->name_off = name_off; >> + t->type = ref_type_id; >> + >> + if (comp_id == -1) >> + for_ref_type = true; >> + t->info = btf_type_info(BTF_KIND_TAG, 0, for_ref_type); >> + ((struct btf_tag *)(t + 1))->comp_id = for_ref_type ? 0 : comp_id; > > As I mentioned in the previous patch, it feels cleaner to just have > this -1 special value and not utilize kflag at all. It will match > libbpf API as you defined it naturally. will do. > >> + >> + return btf_commit_type(btf, sz); >> +} >> + > > [...] > >> case BTF_KIND_ARRAY: { >> diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h >> index 4a711f990904..a78cf8331d49 100644 >> --- a/tools/lib/bpf/btf.h >> +++ b/tools/lib/bpf/btf.h >> @@ -141,6 +141,9 @@ LIBBPF_API int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz >> LIBBPF_API int btf__add_datasec_var_info(struct btf *btf, int var_type_id, >> __u32 offset, __u32 byte_sz); >> >> +/* tag contruction API */ > > typo: construction, but I'd put it after btf__add_restrict with no comment ack. > >> +LIBBPF_API int btf__add_tag(struct btf *btf, const char *name, int comp_id, int ref_type_id); >> + >> struct btf_dedup_opts { >> unsigned int dedup_table_size; >> bool dont_resolve_fwds; >> @@ -328,6 +331,11 @@ static inline bool btf_is_float(const struct btf_type *t) >> return btf_kind(t) == BTF_KIND_FLOAT; >> } >> >> +static inline bool btf_is_tag(const struct btf_type *t) >> +{ >> + return btf_kind(t) == BTF_KIND_TAG; >> +} >> + >> static inline __u8 btf_int_encoding(const struct btf_type *t) >> { >> return BTF_INT_ENCODING(*(__u32 *)(t + 1)); >> @@ -396,6 +404,11 @@ btf_var_secinfos(const struct btf_type *t) >> return (struct btf_var_secinfo *)(t + 1); >> } >> > > please add `struct btf_tag;` forward reference for those users who are > compiling with old UAPI headers. okay. > >> +static inline struct btf_tag *btf_tag(const struct btf_type *t) >> +{ >> + return (struct btf_tag *)(t + 1); >> +} >> + >> #ifdef __cplusplus >> } /* extern "C" */ >> #endif > > [...] > >> LIBBPF_0.5.0 { >> global: >> + btf__add_tag; >> bpf_map__initial_value; >> bpf_map__pin_path; >> bpf_map_lookup_and_delete_elem_flags; >> diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h >> index 533b0211f40a..7deb86d9af51 100644 >> --- a/tools/lib/bpf/libbpf_internal.h >> +++ b/tools/lib/bpf/libbpf_internal.h >> @@ -69,6 +69,8 @@ >> #define BTF_VAR_SECINFO_ENC(type, offset, size) (type), (offset), (size) >> #define BTF_TYPE_FLOAT_ENC(name, sz) \ >> BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_FLOAT, 0, 0), sz) >> +#define BTF_TYPE_TAG_KIND_ENC(name, type) \ > > following other macro names, it should be BTF_TYPE_TAG_ENC, no? This is to differentiate the case from attr to member/func_argument which is implemented in selftest test_btf.h. But with the new scheme, we just need BTF_TYPE_TAG_ENC. Will change. > >> + BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_TAG, 1, 0), type), (0) >> >> #ifndef likely >> #define likely(x) __builtin_expect(!!(x), 1) >> -- >> 2.30.2 >>
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 7cb6ebf1be37..ed02b17aad17 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -304,6 +304,8 @@ static int btf_type_size(const struct btf_type *t) return base_size + sizeof(struct btf_var); case BTF_KIND_DATASEC: return base_size + vlen * sizeof(struct btf_var_secinfo); + case BTF_KIND_TAG: + return base_size + sizeof(struct btf_tag); default: pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t)); return -EINVAL; @@ -376,6 +378,9 @@ static int btf_bswap_type_rest(struct btf_type *t) v->size = bswap_32(v->size); } return 0; + case BTF_KIND_TAG: + btf_tag(t)->comp_id = bswap_32(btf_tag(t)->comp_id); + return 0; default: pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t)); return -EINVAL; @@ -586,6 +591,7 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id) case BTF_KIND_CONST: case BTF_KIND_RESTRICT: case BTF_KIND_VAR: + case BTF_KIND_TAG: type_id = t->type; break; case BTF_KIND_ARRAY: @@ -2440,6 +2446,41 @@ int btf__add_datasec_var_info(struct btf *btf, int var_type_id, __u32 offset, __ return 0; } +int btf__add_tag(struct btf *btf, const char *name, int comp_id, int ref_type_id) +{ + bool for_ref_type = false; + struct btf_type *t; + int sz, name_off; + + if (!name || !name[0] || comp_id < -1) + return libbpf_err(-EINVAL); + + if (validate_type_id(ref_type_id)) + return libbpf_err(-EINVAL); + + if (btf_ensure_modifiable(btf)) + return libbpf_err(-ENOMEM); + + sz = sizeof(struct btf_type) + sizeof(struct btf_tag); + t = btf_add_type_mem(btf, sz); + if (!t) + return libbpf_err(-ENOMEM); + + name_off = btf__add_str(btf, name); + if (name_off < 0) + return name_off; + + t->name_off = name_off; + t->type = ref_type_id; + + if (comp_id == -1) + for_ref_type = true; + t->info = btf_type_info(BTF_KIND_TAG, 0, for_ref_type); + ((struct btf_tag *)(t + 1))->comp_id = for_ref_type ? 0 : comp_id; + + return btf_commit_type(btf, sz); +} + struct btf_ext_sec_setup_param { __u32 off; __u32 len; @@ -3535,6 +3576,7 @@ static int btf_dedup_prep(struct btf_dedup *d) h = btf_hash_common(t); break; case BTF_KIND_INT: + case BTF_KIND_TAG: h = btf_hash_int_tag(t); break; case BTF_KIND_ENUM: @@ -3590,6 +3632,7 @@ static int btf_dedup_prim_type(struct btf_dedup *d, __u32 type_id) case BTF_KIND_FUNC_PROTO: case BTF_KIND_VAR: case BTF_KIND_DATASEC: + case BTF_KIND_TAG: return 0; case BTF_KIND_INT: @@ -4210,6 +4253,23 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id) } break; + case BTF_KIND_TAG: + ref_type_id = btf_dedup_ref_type(d, t->type); + if (ref_type_id < 0) + return ref_type_id; + t->type = ref_type_id; + + h = btf_hash_int_tag(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_int_tag(t, cand)) { + new_id = cand_id; + break; + } + } + break; + case BTF_KIND_ARRAY: { struct btf_array *info = btf_array(t); @@ -4482,6 +4542,7 @@ int btf_type_visit_type_ids(struct btf_type *t, type_id_visit_fn visit, void *ct case BTF_KIND_TYPEDEF: case BTF_KIND_FUNC: case BTF_KIND_VAR: + case BTF_KIND_TAG: return visit(&t->type, ctx); case BTF_KIND_ARRAY: { diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h index 4a711f990904..a78cf8331d49 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -141,6 +141,9 @@ LIBBPF_API int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz LIBBPF_API int btf__add_datasec_var_info(struct btf *btf, int var_type_id, __u32 offset, __u32 byte_sz); +/* tag contruction API */ +LIBBPF_API int btf__add_tag(struct btf *btf, const char *name, int comp_id, int ref_type_id); + struct btf_dedup_opts { unsigned int dedup_table_size; bool dont_resolve_fwds; @@ -328,6 +331,11 @@ static inline bool btf_is_float(const struct btf_type *t) return btf_kind(t) == BTF_KIND_FLOAT; } +static inline bool btf_is_tag(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_TAG; +} + static inline __u8 btf_int_encoding(const struct btf_type *t) { return BTF_INT_ENCODING(*(__u32 *)(t + 1)); @@ -396,6 +404,11 @@ btf_var_secinfos(const struct btf_type *t) return (struct btf_var_secinfo *)(t + 1); } +static inline struct btf_tag *btf_tag(const struct btf_type *t) +{ + return (struct btf_tag *)(t + 1); +} + #ifdef __cplusplus } /* extern "C" */ #endif diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c index e4b483f15fb9..ad6df97295ae 100644 --- a/tools/lib/bpf/btf_dump.c +++ b/tools/lib/bpf/btf_dump.c @@ -316,6 +316,7 @@ static int btf_dump_mark_referenced(struct btf_dump *d) case BTF_KIND_TYPEDEF: case BTF_KIND_FUNC: case BTF_KIND_VAR: + case BTF_KIND_TAG: d->type_states[t->type].referenced = 1; break; @@ -583,6 +584,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr) case BTF_KIND_FUNC: case BTF_KIND_VAR: case BTF_KIND_DATASEC: + case BTF_KIND_TAG: d->type_states[id].order_state = ORDERED; return 0; @@ -2215,6 +2217,7 @@ static int btf_dump_dump_type_data(struct btf_dump *d, case BTF_KIND_FWD: case BTF_KIND_FUNC: case BTF_KIND_FUNC_PROTO: + case BTF_KIND_TAG: err = btf_dump_unsupported_data(d, t, id); break; case BTF_KIND_INT: diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 88d8825fc6f6..4bee9eb64aa0 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -195,6 +195,8 @@ enum kern_feature_id { FEAT_BTF_FLOAT, /* BPF perf link support */ FEAT_PERF_LINK, + /* BTF_KIND_ATTR support */ + FEAT_BTF_TAG, __FEAT_CNT, }; @@ -1987,6 +1989,7 @@ static const char *__btf_kind_str(__u16 kind) case BTF_KIND_VAR: return "var"; case BTF_KIND_DATASEC: return "datasec"; case BTF_KIND_FLOAT: return "float"; + case BTF_KIND_TAG: return "tag"; default: return "unknown"; } } @@ -2486,8 +2489,9 @@ static bool btf_needs_sanitization(struct bpf_object *obj) bool has_datasec = kernel_supports(obj, FEAT_BTF_DATASEC); bool has_float = kernel_supports(obj, FEAT_BTF_FLOAT); bool has_func = kernel_supports(obj, FEAT_BTF_FUNC); + bool has_tag = kernel_supports(obj, FEAT_BTF_TAG); - return !has_func || !has_datasec || !has_func_global || !has_float; + return !has_func || !has_datasec || !has_func_global || !has_float || !has_tag; } static void bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf) @@ -2496,14 +2500,15 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf) bool has_datasec = kernel_supports(obj, FEAT_BTF_DATASEC); bool has_float = kernel_supports(obj, FEAT_BTF_FLOAT); bool has_func = kernel_supports(obj, FEAT_BTF_FUNC); + bool has_tag = kernel_supports(obj, FEAT_BTF_TAG); struct btf_type *t; int i, j, vlen; for (i = 1; i <= btf__get_nr_types(btf); i++) { t = (struct btf_type *)btf__type_by_id(btf, i); - if (!has_datasec && btf_is_var(t)) { - /* replace VAR with INT */ + if ((!has_datasec && btf_is_var(t)) || (!has_tag && btf_is_tag(t))) { + /* replace VAR/TAG with INT */ t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0); /* * using size = 1 is the safest choice, 4 will be too @@ -4207,6 +4212,23 @@ static int probe_kern_btf_float(void) strs, sizeof(strs))); } +static int probe_kern_btf_tag(void) +{ + static const char strs[] = "\0tag"; + __u32 types[] = { + /* int */ + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ + /* VAR x */ /* [2] */ + BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1), + BTF_VAR_STATIC, + /* attr */ + BTF_TYPE_TAG_KIND_ENC(1, 2), + }; + + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs))); +} + static int probe_kern_array_mmap(void) { struct bpf_create_map_attr attr = { @@ -4423,6 +4445,9 @@ static struct kern_feature_desc { [FEAT_PERF_LINK] = { "BPF perf link support", probe_perf_link, }, + [FEAT_BTF_TAG] = { + "BTF_KIND_TAG support", probe_kern_btf_tag, + }, }; static bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id) diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index bbc53bb25f68..62c4c932ef6a 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -370,6 +370,7 @@ LIBBPF_0.4.0 { LIBBPF_0.5.0 { global: + btf__add_tag; bpf_map__initial_value; bpf_map__pin_path; bpf_map_lookup_and_delete_elem_flags; diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index 533b0211f40a..7deb86d9af51 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -69,6 +69,8 @@ #define BTF_VAR_SECINFO_ENC(type, offset, size) (type), (offset), (size) #define BTF_TYPE_FLOAT_ENC(name, sz) \ BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_FLOAT, 0, 0), sz) +#define BTF_TYPE_TAG_KIND_ENC(name, type) \ + BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_TAG, 1, 0), type), (0) #ifndef likely #define likely(x) __builtin_expect(!!(x), 1)
Add BTF_KIND_TAG support for parsing and dedup. Also added sanitization for BTF_KIND_TAG. If BTF_KIND_TAG is not supported in the kernel, sanitize it to INTs. Signed-off-by: Yonghong Song <yhs@fb.com> --- tools/lib/bpf/btf.c | 61 +++++++++++++++++++++++++++++++++ tools/lib/bpf/btf.h | 13 +++++++ tools/lib/bpf/btf_dump.c | 3 ++ tools/lib/bpf/libbpf.c | 31 +++++++++++++++-- tools/lib/bpf/libbpf.map | 1 + tools/lib/bpf/libbpf_internal.h | 2 ++ 6 files changed, 108 insertions(+), 3 deletions(-)