[PATCH bpf-next] selftests/bpf: Add docs target as all dependency

[Jiri Olsa <jolsa@kernel.org>]

Currently docs target is make dependency for TEST_GEN_FILES,
which makes tests to be rebuilt every time you run make.

Adding docs as all target dependency, so when running make
on top of built selftests it will show just:

  $ make
  make[1]: Nothing to be done for 'docs'.

After cleaning docs, only docs is rebuilt:

  $ make docs-clean
  CLEAN    eBPF_helpers-manpage
  CLEAN    eBPF_syscall-manpage
  $ make
  GEN      ...selftests/bpf/bpf-helpers.rst
  GEN      ...selftests/bpf/bpf-helpers.7
  GEN      ...selftests/bpf/bpf-syscall.rst
  GEN      ...selftests/bpf/bpf-syscall.2
  $ make
  make[1]: Nothing to be done for 'docs'.

Cc: Joe Stringer <joe@cilium.io>
Fixes: a01d935b2e09 ("tools/bpf: Remove bpf-helpers from bpftool docs")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 tools/testing/selftests/bpf/Makefile | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index c45ae13b88a0..c5bcdb3d4b12 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -187,7 +187,6 @@ $(OUTPUT)/runqslower: $(BPFOBJ) | $(DEFAULT_BPFTOOL)
 		    cp $(SCRATCH_DIR)/runqslower $@
 
 $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED): $(OUTPUT)/test_stub.o $(BPFOBJ)
-$(TEST_GEN_FILES): docs
 
 $(OUTPUT)/test_dev_cgroup: cgroup_helpers.c
 $(OUTPUT)/test_skb_cgroup_id_user: cgroup_helpers.c
@@ -210,6 +209,8 @@ $(DEFAULT_BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile)    \
 		    OUTPUT=$(HOST_BUILD_DIR)/bpftool/			       \
 		    prefix= DESTDIR=$(HOST_SCRATCH_DIR)/ install
 
+all: docs
+
 docs:
 	$(Q)RST2MAN_OPTS="--exit-status=1" $(MAKE) $(submake_extras)	\
 	            -f Makefile.docs					\
-- 
2.30.2