Commit ee3e46b7 authored by Masahiro Yamada's avatar Masahiro Yamada
Browse files

kbuild: refactor modversions build rules 



Let $(CC) compile objects into normal files *.o instead of .tmp_*.o
whether CONFIG_MODVERSIONS is enabled or not. With this, the input
file for objtool is always *.o so objtool_o can go away.

I guess the reason of using .tmp_*.o for intermediate objects was
to avoid leaving incomplete *.o file (, whose timestamp says it is
up-to-date) when the genksyms tool failed for some reasons.

It no longer matters because any targets are deleted on errors since
commit 9c2af1c7 ("kbuild: add .DELETE_ON_ERROR special target").

Signed-off-by: default avatarMasahiro Yamada <yamada.masahiro@socionext.com>
parent 4317ee3b

scripts/Makefile.build

+17 −37
Original line number Diff line number Diff line
@@ -154,35 +154,30 @@ $(obj)/%.ll: $(src)/%.c FORCE 
# (See cmd_cc_o_c + relevant part of rule_cc_o_c)



quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@



ifndef CONFIG_MODVERSIONS

      cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<



else

ifdef CONFIG_MODVERSIONS

# When module versioning is enabled the following steps are executed:

# o compile a .tmp_<file>.o from <file>.c

# o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does

#   not export symbols, we just rename .tmp_<file>.o to <file>.o and

#   are done.

# o compile a <file>.o from <file>.c

# o if <file>.o doesn't contain a __ksymtab version, i.e. does

#   not export symbols, it's done.

# o otherwise, we calculate symbol versions using the good old

#   genksyms on the preprocessed source and postprocess them in a way

#   that they are usable as a linker script

# o generate <file>.o from .tmp_<file>.o using the linker to

# o generate .tmp_<file>.o from <file>.o using the linker to

#   replace the unresolved symbols __crc_exported_symbol with

#   the actual value of the checksum generated by genksyms



cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<

# o remove .tmp_<file>.o to <file>.o



cmd_modversions_c =								\

	if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then		\

	if $(OBJDUMP) -h $@ | grep -q __ksymtab; then				\

		$(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))	\

		    > $(@D)/.tmp_$(@F:.o=.ver);					\

										\

		$(LD) $(KBUILD_LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) 		\

		$(LD) $(KBUILD_LDFLAGS) -r -o $(@D)/.tmp_$(@F) $@ 		\

			-T $(@D)/.tmp_$(@F:.o=.ver);				\

		rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);		\

	else									\

		mv -f $(@D)/.tmp_$(@F) $@;					\

		rm -f $(@D)/.tmp_$(@F:.o=.ver);					\

	fi;

endif
@@ -241,19 +236,12 @@ ifneq ($(RETPOLINE_CFLAGS),) 
endif

endif





ifdef CONFIG_MODVERSIONS

objtool_o = $(@D)/.tmp_$(@F)

else

objtool_o = $(@)

endif



# 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory

# 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file

# 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file

cmd_objtool = $(if $(patsubst y%,, \

	$(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \

	$(__objtool_obj) $(objtool_args) "$(objtool_o)";)

	$(__objtool_obj) $(objtool_args) $@;)

objtool_obj = $(if $(patsubst y%,, \

	$(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \

	$(__objtool_obj))
@@ -357,34 +345,26 @@ $(obj)/%.s: $(src)/%.S FORCE 
	$(call if_changed_dep,cpp_s_S)



quiet_cmd_as_o_S = AS $(quiet_modtag)  $@



ifndef CONFIG_MODVERSIONS

      cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<



else

ifdef CONFIG_MODVERSIONS



ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)



ifeq ($(ASM_PROTOTYPES),)

cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<



else

ifneq ($(ASM_PROTOTYPES),)



# versioning matches the C process described above, with difference that

# we parse asm-prototypes.h C header to get function definitions.



cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $<



cmd_modversions_S =								\

	if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then		\

	if $(OBJDUMP) -h $@ | grep -q __ksymtab; then				\

		$(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))	\

		    > $(@D)/.tmp_$(@F:.o=.ver);					\

										\

		$(LD) $(KBUILD_LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) 		\

		$(LD) $(KBUILD_LDFLAGS) -r -o $(@D)/.tmp_$(@F) $@ 		\

			-T $(@D)/.tmp_$(@F:.o=.ver);				\

		rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);		\

	else									\

		mv -f $(@D)/.tmp_$(@F) $@;					\

		rm -f $(@D)/.tmp_$(@F:.o=.ver);					\

	fi;

endif

endif

CRA Git | Maintained and supported by SUSTech CRA and CCSE