Re: [net-next PATCH 4/4] samples/bpf: allow make to be run from samples/bpf/ directory

Alexei Starovoitov
2016-04-26T14:35:30Z

On Tue, Apr 26, 2016 at 01:09:32PM +0200, Jesper Dangaard Brouer wrote:
> It is not intuitive that 'make' must be run from the top level
> directory with argument "samples/bpf/" to compile these eBPF samples.
>
> Introduce a kbuild make file trick that allow make to be run from the
> "samples/bpf/" directory itself. It basically change to the top level
> directory and call "make samples/bpf/" with the "/" slash after the
> directory name.
>
> Also add a clean target that only cleans this directory, by taking
> advantage of the kbuild external module setting M=$PWD.
>
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
> ---
> samples/bpf/Makefile | 8 ++++++++
> samples/bpf/README.rst | 3 +++
> 2 files changed, 11 insertions(+)
>
> diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
> index 7ac66f5bbbf5..7370dfee482f 100644
> --- a/samples/bpf/Makefile
> +++ b/samples/bpf/Makefile
> @@ -85,6 +85,14 @@ HOSTLOADLIBES_test_overhead += -lelf -lrt
> # make samples/bpf/ LLC=~/git/llvm/build/bin/llc
> LLC ?= llc
>
> +# Trick to allow make to be run from this directory
> +all:
> + $(MAKE) -C ../../ $$PWD/
> +
> +clean:
> + $(MAKE) -C ../../ M=$$PWD clean
> + @rm -f *~
> +

nice trick!