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 <[email protected]>
---
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 $@
+$(TEST_GEN_OBJ): %.o: %.c
+ $(CC) $(CFLAGS) $(CPPFLAGS) $(EXTRA_CFLAGS) $(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
- $(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c $< -o $@
+ $(CC) $(CFLAGS) $(CPPFLAGS) $(EXTRA_CFLAGS) $(TARGET_ARCH) -c $< -o $@
$(LIBKVM_S_OBJ): $(OUTPUT)/%.o: %.S
$(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c $< -o $@
--
2.25.1
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 <[email protected]>
> ---
> 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
--
> 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.
No, we don't. I added "-MD" in EXTRA_CFLAGS, so that only .o files would
be impacted when generating dependency files. But it is unnecessary.
As to the LIBKVM_STRING_OBJ target, it is my negligence. :)
I tried your suggested fix, and it works fine. Will send out v2(based on
selftests branch of github.com/kvm-x86/linux). Thanks!
B.R.
Yu
>
> 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
> --
>