Fix race condition when running generate_psa_tests.py
Fix a race condition in parallel builds: when generating *.data files with
generate_psa_tests.py, make instantiated the recipe once per output file,
potentially resulting in multiple instances of generate_psa_tests.py running
in parallel. This not only was inefficient, but occasionally caused the
output to be corrupted (https://github.com/ARMmbed/mbedtls/issues/4773). Fix
this by ensuring the recipe only runs once.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/tests/Makefile b/tests/Makefile
index c1620d6..6695437 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -63,18 +63,25 @@
GENERATED_FILES := $(GENERATED_DATA_FILES)
generated_files: $(GENERATED_FILES)
-$(GENERATED_DATA_FILES): scripts/generate_psa_tests.py
+# generate_psa_tests.py spends more time analyzing inputs than generating
+# outputs. Its inputs are the same no matter which files are being generated.
+# It's rare not to want all the outputs. So always generate all of its outputs.
+# Use an intermediate phony dependency so that parallel builds don't run
+# a separate instance of the recipe for each output file.
+.SECONDARY: generated_psa_test_data
+$(GENERATED_DATA_FILES): generated_psa_test_data
+generated_psa_test_data: scripts/generate_psa_tests.py
## The generated file only depends on the options that are present in
## crypto_config.h, not on which options are set. To avoid regenerating this
## file all the time when switching between configurations, don't declare
## crypto_config.h as a dependency. Remove this file from your working tree
## if you've just added or removed an option in crypto_config.h.
-#$(GENERATED_DATA_FILES): ../include/psa/crypto_config.h
-$(GENERATED_DATA_FILES): ../include/psa/crypto_values.h
-$(GENERATED_DATA_FILES): ../include/psa/crypto_extra.h
-$(GENERATED_DATA_FILES): suites/test_suite_psa_crypto_metadata.data
-$(GENERATED_DATA_FILES):
- echo " Gen $@ ..."
+#generated_psa_test_data: ../include/psa/crypto_config.h
+generated_psa_test_data: ../include/psa/crypto_values.h
+generated_psa_test_data: ../include/psa/crypto_extra.h
+generated_psa_test_data: suites/test_suite_psa_crypto_metadata.data
+generated_psa_test_data:
+ echo " Gen $(GENERATED_DATA_FILES) ..."
$(PYTHON) scripts/generate_psa_tests.py
# A test application is built for each suites/test_suite_*.data file.
