Based on recent BPF CO-RE, tp_btf, and skeleton changes, re-implement BCC-based runqslower tool as portable pre-compiled BPF CO-RE-based tool. Make sure it's built as part of selftests to ensure it doesn't bit rot. As part of this patch set, also introduce new `format core` to `bpftool btf dump` sub-command. It generates same compilable C header file with all the types from BTF, but additionally ensures seamless use of generated header with BPF CO-RE. Currently `format core` applies preserve_access_index attribute (if supported by Clang) to all structs and unions, to improve user experience of writing TRACING programs with direct kernel memory read access. Andrii Nakryiko (3): bpftool: add extra CO-RE mode to btf dump command libbpf/tools: add runqslower tool to libbpf selftests/bpf: build runqslower from selftests .../bpf/bpftool/Documentation/bpftool-btf.rst | 7 +- tools/bpf/bpftool/bash-completion/bpftool | 2 +- tools/bpf/bpftool/btf.c | 24 ++- tools/lib/bpf/tools/runqslower/.gitignore | 2 + tools/lib/bpf/tools/runqslower/Makefile | 60 ++++++ .../lib/bpf/tools/runqslower/runqslower.bpf.c | 101 ++++++++++ tools/lib/bpf/tools/runqslower/runqslower.c | 187 ++++++++++++++++++ tools/lib/bpf/tools/runqslower/runqslower.h | 13 ++ tools/testing/selftests/bpf/Makefile | 7 +- 9 files changed, 395 insertions(+), 8 deletions(-) create mode 100644 tools/lib/bpf/tools/runqslower/.gitignore create mode 100644 tools/lib/bpf/tools/runqslower/Makefile create mode 100644 tools/lib/bpf/tools/runqslower/runqslower.bpf.c create mode 100644 tools/lib/bpf/tools/runqslower/runqslower.c create mode 100644 tools/lib/bpf/tools/runqslower/runqslower.h -- 2.17.1
