[PATCH v2 2/2] selftests/lib.mk: Introduce check to validate required configs

[Siddharth Menon <simeddon@gmail.com>]

Currently, kselftests does not have a generalised mechanism to skip compilation
and run tests when required kernel configuration flags are missing.

This patch introduces a check to validate the presence of required config flags
specified in the selftest config files. In case scripts/config or the current
kernel config is not found, this check is skipped.

In order to view the missing config options required to compile the test,
set the environment variable LOCALMODCONFIG_DEBUG=1.

example usage:
```
LOCALMODCONFIG_DEBUG=1 make -C livepatch/
```

Suggested-by: Petr Mladek <pmladek@suse.com>
Suggested-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Siddharth Menon <simeddon@gmail.com>
---
 v1->v2: moved the config checking logic to a separate perl script
 tools/testing/selftests/lib.mk | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)
 mode change 100644 => 100755 tools/testing/selftests/lib.mk

diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk
old mode 100644
new mode 100755
index d6edcfcb5be8..98dda6d8d702
--- a/tools/testing/selftests/lib.mk
+++ b/tools/testing/selftests/lib.mk
@@ -97,7 +97,14 @@ TEST_GEN_PROGS := $(patsubst %,$(OUTPUT)/%,$(TEST_GEN_PROGS))
 TEST_GEN_PROGS_EXTENDED := $(patsubst %,$(OUTPUT)/%,$(TEST_GEN_PROGS_EXTENDED))
 TEST_GEN_FILES := $(patsubst %,$(OUTPUT)/%,$(TEST_GEN_FILES))
 
-all: $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED) $(TEST_GEN_FILES) \
+TEST_DIR := $(shell pwd)
+
+check_config_deps:
+	@$(selfdir)/mktest.pl $(TEST_DIR)/config || \
+	{ echo "Skipping test: $(notdir $(TEST_DIR))"; exit 1; }
+
+
+all: check_config_deps $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED) $(TEST_GEN_FILES) \
 	$(if $(TEST_GEN_MODS_DIR),gen_mods_dir)
 
 define RUN_TESTS
@@ -228,4 +235,4 @@ $(OUTPUT)/%:%.S
 	$(LINK.S) $^ $(LDLIBS) -o $@
 endif
 
-.PHONY: run_tests all clean install emit_tests gen_mods_dir clean_mods_dir
+.PHONY: run_tests all clean install emit_tests gen_mods_dir clean_mods_dir check_config_deps
-- 
2.39.5