[PATCH v3 0/4] btf: support ints larger than 128 bits

From: Sean Young
Date: Tue Jan 05 2021 - 09:47:16 EST


clang supports arbitrary length ints using the _ExtInt extension. This
can be useful to hold very large values, e.g. 256 bit or 512 bit types.

Larger types (e.g. 1024 bits) are possible but I am unaware of a use
case for these.

This requires the _ExtInt extension enabled in clang, which is under
review.

Link: https://clang.llvm.org/docs/LanguageExtensions.html#extended-integer-types
Link: https://reviews.llvm.org/D93103

Signed-off-by: Sean Young <sean@xxxxxxxx>

changes since v2:
- split patches into 4 distinct patches

changes since v1:
- added tests as suggested by Yonghong Song
- added kernel pretty-printer


Sean Young (4):
btf: add support for ints larger than 128 bits
libbpf: add support for ints larger than 128 bits
bpftool: add support for ints larger than 128 bits
bpf: add tests for ints larger than 128 bits

Documentation/bpf/btf.rst | 4 +-
include/uapi/linux/btf.h | 2 +-
kernel/bpf/btf.c | 54 +-
tools/bpf/bpftool/btf_dumper.c | 40 ++
tools/include/uapi/linux/btf.h | 2 +-
tools/lib/bpf/btf.c | 2 +-
tools/testing/selftests/bpf/Makefile | 3 +-
tools/testing/selftests/bpf/prog_tests/btf.c | 3 +-
.../selftests/bpf/progs/test_btf_extint.c | 50 ++
tools/testing/selftests/bpf/test_extint.py | 535 ++++++++++++++++++
10 files changed, 679 insertions(+), 16 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/test_btf_extint.c
create mode 100755 tools/testing/selftests/bpf/test_extint.py

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2.29.2