tools: bpftool: improve and check builds for different make invocations
There are a number of alternative "make" invocations that can be used to
compile bpftool. The following invocations are expected to work:
- through the kbuild system, from the top of the repository
(make tools/bpf)
- by telling make to change to the bpftool directory
(make -C tools/bpf/bpftool)
- by building the BPF tools from tools/
(cd tools && make bpf)
- by running make from bpftool directory
(cd tools/bpf/bpftool && make)
Additionally, setting the O or OUTPUT variables should tell the build
system to use a custom output path, for each of these alternatives.
The following patch fixes the following invocations:
$ make tools/bpf
$ make tools/bpf O=<dir>
$ make -C tools/bpf/bpftool OUTPUT=<dir>
$ make -C tools/bpf/bpftool O=<dir>
$ cd tools/ && make bpf O=<dir>
$ cd tools/bpf/bpftool && make OUTPUT=<dir>
$ cd tools/bpf/bpftool && make O=<dir>
After this commit, the build still fails for two variants when passing
the OUTPUT variable:
$ make tools/bpf OUTPUT=<dir>
$ cd tools/ && make bpf OUTPUT=<dir>
In order to remember and check what make invocations are supposed to
work, and to document the ones which do not, a new script is added to
the BPF selftests. Note that some invocations require the kernel to be
configured, so the script skips them if no .config file is found.
v2:
- In make_and_clean(), set $ERROR to 1 when "make" returns non-zero,
even if the binary was produced.
- Run "make clean" from the correct directory (bpf/ instead of bpftool/,
when relevant).
Reported-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
3 files changed