On Fri, Jan 27, 2023, Yu Zhang wrote:
Currently, KVM selftests have to run "make clean && make" to rebuild the entire test suite each time a header file is modified. Define "-MD" as an EXTRA_CFLAGS, so we can generate the dependency rules for each target object, whose prerequisites contains the source file and the included header files as well. And including those dependency files in KVM selftests' makefile will release us from such annoyance.
Signed-off-by: Yu Zhang yu.c.zhang@linux.intel.com
tools/testing/selftests/kvm/Makefile | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 1750f91dd936..b329e0d1a460 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -180,6 +180,8 @@ TEST_GEN_PROGS += $(TEST_GEN_PROGS_$(ARCH_DIR)) TEST_GEN_PROGS_EXTENDED += $(TEST_GEN_PROGS_EXTENDED_$(ARCH_DIR)) LIBKVM += $(LIBKVM_$(ARCH_DIR)) +OVERRIDE_TARGETS = 1
# lib.mak defines $(OUTPUT), prepends $(OUTPUT)/ to $(TEST_GEN_PROGS), and most # importantly defines, i.e. overwrites, $(CC) (unless `make -e` or `make CC=`, # which causes the environment variable to override the makefile). @@ -198,9 +200,11 @@ CFLAGS += -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99 \ -fno-builtin-memcmp -fno-builtin-memcpy -fno-builtin-memset \ -fno-stack-protector -fno-PIE -I$(LINUX_TOOL_INCLUDE) \ -I$(LINUX_TOOL_ARCH_INCLUDE) -I$(LINUX_HDR_PATH) -Iinclude \
- -I$(<D) -Iinclude/$(ARCH_DIR) -I ../rseq -I.. $(EXTRA_CFLAGS) \
- -I$(<D) -Iinclude/$(ARCH_DIR) -I ../rseq -I.. \ $(KHDR_INCLUDES)
+EXTRA_CFLAGS += -MD
no-pie-option := $(call try-run, echo 'int main(void) { return 0; }' | \ $(CC) -Werror $(CFLAGS) -no-pie -x c - -o "$$TMP", -no-pie) @@ -218,11 +222,22 @@ LIBKVM_S_OBJ := $(patsubst %.S, $(OUTPUT)/%.o, $(LIBKVM_S)) LIBKVM_STRING_OBJ := $(patsubst %.c, $(OUTPUT)/%.o, $(LIBKVM_STRING)) LIBKVM_OBJS = $(LIBKVM_C_OBJ) $(LIBKVM_S_OBJ) $(LIBKVM_STRING_OBJ) -EXTRA_CLEAN += $(LIBKVM_OBJS) cscope.* +TEST_GEN_OBJ = $(patsubst %, %.o, $(TEST_GEN_PROGS)) +TEST_GEN_OBJ += $(patsubst %, %.o, $(TEST_GEN_PROGS_EXTENDED)) +TEST_DEP_FILES = $(patsubst %.o, %.d, $(TEST_GEN_OBJ)) +TEST_DEP_FILES += $(patsubst %.o, %.d, $(LIBKVM_OBJS)) +-include $(TEST_DEP_FILES)
+$(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED): %: %.o
- $(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH) $< $(LIBKVM_OBJS) $(LDLIBS) -o $@
Do we actually need to omit -MD here? IIUC, it just means that the .d file will get redundantly generated when building the final executable. I would much prefer to build everything with the same options unless there's a good reason not to, e.g. this patch doesn't feed -MD into the LIBKVM_STRING_OBJ target, which seems wrong.
I.e. why not simply
--- tools/testing/selftests/kvm/Makefile | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 152c1a988e42..faaf65aa7621 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -182,6 +182,8 @@ TEST_GEN_PROGS += $(TEST_GEN_PROGS_$(ARCH_DIR)) TEST_GEN_PROGS_EXTENDED += $(TEST_GEN_PROGS_EXTENDED_$(ARCH_DIR)) LIBKVM += $(LIBKVM_$(ARCH_DIR))
+OVERRIDE_TARGETS = 1 + # lib.mak defines $(OUTPUT), prepends $(OUTPUT)/ to $(TEST_GEN_PROGS), and most # importantly defines, i.e. overwrites, $(CC) (unless `make -e` or `make CC=`, # which causes the environment variable to override the makefile). @@ -196,7 +198,7 @@ else LINUX_TOOL_ARCH_INCLUDE = $(top_srcdir)/tools/arch/$(ARCH)/include endif CFLAGS += -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99 \ - -Wno-gnu-variable-sized-type-not-at-end \ + -Wno-gnu-variable-sized-type-not-at-end -MD \ -fno-builtin-memcmp -fno-builtin-memcpy -fno-builtin-memset \ -fno-stack-protector -fno-PIE -I$(LINUX_TOOL_INCLUDE) \ -I$(LINUX_TOOL_ARCH_INCLUDE) -I$(LINUX_HDR_PATH) -Iinclude \ @@ -223,7 +225,18 @@ LIBKVM_S_OBJ := $(patsubst %.S, $(OUTPUT)/%.o, $(LIBKVM_S)) LIBKVM_STRING_OBJ := $(patsubst %.c, $(OUTPUT)/%.o, $(LIBKVM_STRING)) LIBKVM_OBJS = $(LIBKVM_C_OBJ) $(LIBKVM_S_OBJ) $(LIBKVM_STRING_OBJ)
-EXTRA_CLEAN += $(LIBKVM_OBJS) cscope.* +TEST_GEN_OBJ = $(patsubst %, %.o, $(TEST_GEN_PROGS)) +TEST_GEN_OBJ += $(patsubst %, %.o, $(TEST_GEN_PROGS_EXTENDED)) +TEST_DEP_FILES = $(patsubst %.o, %.d, $(TEST_GEN_OBJ)) +TEST_DEP_FILES += $(patsubst %.o, %.d, $(LIBKVM_OBJS)) +-include $(TEST_DEP_FILES) + +$(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED): %: %.o + $(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH) $< $(LIBKVM_OBJS) $(LDLIBS) -o $@ +$(TEST_GEN_OBJ): %.o: %.c + $(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c $< -o $@ + +EXTRA_CLEAN += $(LIBKVM_OBJS) $(TEST_DEP_FILES) $(TEST_GEN_OBJ) cscope.*
x := $(shell mkdir -p $(sort $(dir $(LIBKVM_C_OBJ) $(LIBKVM_S_OBJ)))) $(LIBKVM_C_OBJ): $(OUTPUT)/%.o: %.c
base-commit: 95b9779c1758f03cf494e8550d6249a40089ed1c