hi, this patchset does preparation work for adding d_path helper, which still needs more work, but the initial set of patches is ready and useful to have. This patchset adds: - support to generate BTF ID lists that are resolved during kernel linking and usable within kernel code with following macros: BTF_ID_LIST(bpf_skb_output_btf_ids) BTF_ID(struct, sk_buff) and access it in kernel code via: extern u32 bpf_skb_output_btf_ids[]; - resolve_btfids tool that scans elf object for .BTF_ids section and resolves its symbols with BTF ID values - resolving of bpf_ctx_convert struct and several other objects with BTF_ID_LIST v5 changes: - added acks to patches I did not change in this version - split the original patchset into 2 parts and sending the first one where the support to define BTF list is added, the BTF set support will be posted later on [Andrii] - used u32 instead of int in btf_ids.h [Andrii] - changed the btf_ids.h define guard [Andrii] - added resolve_btfids_clean target [Andrii] - moved resolve_btfids test into prog_tests suite [Andrii] - fixed BTF type iteration index in test [Andrii] - removed btf_id checks in bpf_ctx_convert resolve code [Yonghong] - removed WARN_ON_ONCE from btf_resolve_helper_id [Yonghong] - added BTF_ID_UNUSED macro [Yonghong] - fixed out of the tree build failure [0day bot] Also available at: https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git bpf/d_path thanks, jirka --- Jiri Olsa (9): bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object bpf: Compile resolve_btfids tool at kernel compilation start bpf: Add BTF_ID_LIST/BTF_ID/BTF_ID_UNUSED macros bpf: Resolve BTF IDs in vmlinux image bpf: Remove btf_id helpers resolving bpf: Use BTF_ID to resolve bpf_ctx_convert struct bpf: Add info about .BTF.ids section to btf.rst tools headers: Adopt verbatim copy of btf_ids.h from kernel sources selftests/bpf: Add test for resolve_btfids Documentation/bpf/btf.rst | 36 +++++ Makefile | 25 +++- include/asm-generic/vmlinux.lds.h | 4 + include/linux/btf_ids.h | 87 ++++++++++++ kernel/bpf/btf.c | 103 ++------------ kernel/trace/bpf_trace.c | 9 +- net/core/filter.c | 9 +- scripts/link-vmlinux.sh | 6 + tools/Makefile | 3 + tools/bpf/Makefile | 9 +- tools/bpf/resolve_btfids/Build | 26 ++++ tools/bpf/resolve_btfids/Makefile | 77 +++++++++++ tools/bpf/resolve_btfids/main.c | 716 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ tools/include/linux/btf_ids.h | 87 ++++++++++++ tools/include/linux/compiler.h | 4 + tools/testing/selftests/bpf/Makefile | 22 ++- tools/testing/selftests/bpf/prog_tests/resolve_btfids.c | 170 +++++++++++++++++++++++ 17 files changed, 1289 insertions(+), 104 deletions(-) create mode 100644 include/linux/btf_ids.h create mode 100644 tools/bpf/resolve_btfids/Build create mode 100644 tools/bpf/resolve_btfids/Makefile create mode 100644 tools/bpf/resolve_btfids/main.c create mode 100644 tools/include/linux/btf_ids.h create mode 100644 tools/testing/selftests/bpf/prog_tests/resolve_btfids.c