samples/bpf: allow make to be run from samples/bpf/ directory
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>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 45859c9..dd63521 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -85,6 +85,14 @@
# 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 *~
+
# Verify LLVM compiler is available and bpf target is supported
.PHONY: verify_cmd_llc verify_target_bpf
diff --git a/samples/bpf/README.rst b/samples/bpf/README.rst
index 6f133f3..e36687d 100644
--- a/samples/bpf/README.rst
+++ b/samples/bpf/README.rst
@@ -36,6 +36,9 @@
Do notice the "/" slash after the directory name.
+It is also possible to call make from this directory. This will just
+hide the the invocation of make as above with the appended "/".
+
Manually compiling LLVM with 'bpf' support
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