Libbpf eBPF macro bpf_core_type_id_local

v0.2

The bpf_core_type_id_local macro to get BTF type ID of a specified type, using a local BTF information.

Definition

#define bpf_core_type_id_local(type)                        \
    __builtin_btf_type_id(*___bpf_typeof(type), BPF_TYPE_ID_LOCAL)

Usage

The bpf_core_type_id_local macro to get BTF type ID of a specified type, using a local BTF information. Return 32-bit unsigned integer with type ID from program's own BTF. Always succeeds.

The local type ID can be useful to communicate type info from BPF to userspace or as parameter for kfuncs such as bpf_obj_new_impl or bpf_percpu_obj_new_impl.

This result is determined by the loader library such as libbpf, and set at load time and is considered as a constant value by the verifier.

Example

Docs could be improved

This part of the docs is incomplete, contributions are very welcome