Re: [PATCH v3 bpf-next 00/14] samples: bpf: improve/fix cross-compilation

From: Andrii Nakryiko
Date: Wed Sep 18 2019 - 01:34:55 EST


On Mon, Sep 16, 2019 at 4:02 AM Ivan Khoronzhuk
<ivan.khoronzhuk@xxxxxxxxxx> wrote:
>

Thanks for these changes, they look good overall. It would be great if
someone else could test and validate that cross-compilation works not
just in your environment and generated binaries successfully run on
target machines, though...

[...]


>
> Ivan Khoronzhuk (14):
> samples: bpf: makefile: fix HDR_PROBE "echo"
> samples: bpf: makefile: fix cookie_uid_helper_example obj build
> samples: bpf: makefile: use --target from cross-compile
> samples: bpf: use own EXTRA_CFLAGS for clang commands
> samples: bpf: makefile: use __LINUX_ARM_ARCH__ selector for arm
> samples: bpf: makefile: drop unnecessarily inclusion for bpf_load
> samples: bpf: add makefile.target for separate CC target build
> samples: bpf: makefile: base target programs rules on Makefile.target
> samples: bpf: makefile: use own flags but not host when cross compile
> samples: bpf: makefile: use target CC environment for HDR_PROBE
> libbpf: makefile: add C/CXX/LDFLAGS to libbpf.so and test_libpf
> targets
> samples: bpf: makefile: provide C/CXX/LD flags to libbpf
> samples: bpf: makefile: add sysroot support
> samples: bpf: README: add preparation steps and sysroot info
>

Prefixes like "samples: bpf: makefile: " are very verbose without
adding much value. We've been converging to essentially this set of
prefixes:

- "libbpf:" for libbpf changes
- "bpftool:" for bpftool changes
- "selftests/bpf:" for bpf selftests
- "samples/bpf:" for bpf samples

There is no need to prefix with "makefile: " either. Please update
your patch subjects in the next version. Thanks!

> samples/bpf/Makefile | 179 +++++++++++++++++++++---------------
> samples/bpf/Makefile.target | 75 +++++++++++++++
> samples/bpf/README.rst | 41 ++++++++-
> tools/lib/bpf/Makefile | 11 ++-
> 4 files changed, 225 insertions(+), 81 deletions(-)
> create mode 100644 samples/bpf/Makefile.target
>
> --
> 2.17.1
>