On Tue, Feb 3, 2026 at 1:39 AM Jiri Olsa <[email protected]> wrote:
>
> Adding btf__find_by_glob_kind function that returns array of
> BTF ids that match given kind and allow/deny patterns.
>
> int btf__find_by_glob_kind(const struct btf *btf, __u32 kind,
> const char *allow_pattern,
> const char *deny_pattern,
> __u32 **__ids);
>
> The __ids array is allocated and needs to be manually freed.
>
> The pattern check is done by glob_match function.
>
> Signed-off-by: Jiri Olsa <[email protected]>
> ---
> tools/lib/bpf/btf.c | 41 +++++++++++++++++++++++++++++++++++++++++
> tools/lib/bpf/btf.h | 3 +++
> 2 files changed, 44 insertions(+)
>
> diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
> index 83fe79ffcb8f..64502b3ef38a 100644
> --- a/tools/lib/bpf/btf.c
> +++ b/tools/lib/bpf/btf.c
> @@ -1010,6 +1010,47 @@ __s32 btf__find_by_name_kind(const struct btf *btf,
> const char *type_name,
> return btf_find_by_name_kind(btf, 1, type_name, kind);
> }
>
> +int btf__find_by_glob_kind(const struct btf *btf, __u32 kind,
> + const char *allow_pattern, const char
> *deny_pattern,
> + __u32 **__ids)
> +{
> + __u32 i, nr_types = btf__type_cnt(btf);
> + int cnt = 0, alloc = 0;
> + __u32 *ids = NULL;
> +
> + for (i = 1; i < nr_types; i++) {
> + const struct btf_type *t = btf__type_by_id(btf, i);
> + const char *name;
> + __u32 *p;
> +
> + if (btf_kind(t) != kind)
> + continue;
> + name = btf__name_by_offset(btf, t->name_off);
> + if (!name)
> + continue;
> +
> + if (deny_pattern && glob_match(name, deny_pattern))
> + continue;
> + if (allow_pattern && !glob_match(name, allow_pattern))
> + continue;
> +
> + if (cnt == alloc) {
> + alloc = max(16, alloc * 3 / 2);
> + p = libbpf_reallocarray(ids, alloc, sizeof(__u32));
> + if (!p) {
> + free(ids);
> + return -ENOMEM;
> + }
> + ids = p;
> + }
> + ids[cnt] = i;
> + cnt++;
> + }
> +
> + *__ids = ids;
> + return cnt;
> +}
> +
> static bool btf_is_modifiable(const struct btf *btf)
> {
> return (void *)btf->hdr != btf->raw_data;
> diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h
> index b30008c267c0..d7b47bb0ba99 100644
> --- a/tools/lib/bpf/btf.h
> +++ b/tools/lib/bpf/btf.h
> @@ -661,6 +661,9 @@ static inline struct btf_decl_tag *btf_decl_tag(const
> struct btf_type *t)
> return (struct btf_decl_tag *)(t + 1);
> }
>
> +int btf__find_by_glob_kind(const struct btf *btf, __u32 kind,
> + const char *allow_pattern, const char
> *deny_pattern,
> + __u32 **__ids);
as AI pointed out, this should be an internal helper, no? Let's also
not use double underscore pattern here,
"collect_btf_ids_by_glob_kind()" perhaps?
Also, you don't seem to be using deny_pattern, where you planning to?
Also, are there functions that we'll have BTF for, but they won't be
attachable? What if I do SEC("fentry.multi/*")? Will it attach or fail
to attach some functions (and thus fail the overall attachment)?
> #ifdef __cplusplus
> } /* extern "C" */
> #endif
> --
> 2.52.0
>
