Commit 8017ce50 authored by Masahiro Yamada's avatar Masahiro Yamada
Browse files

kbuild: refactor cmd_modversions_c 



cmd_modversions_c implements two parts; run genksyms to calculate CRCs
of exported symbols, run $(LD) to update the object with the CRCs. The
latter is not executed for CONFIG_LTO_CLANG=y since the object is not
ELF but LLVM bit code at this point.

The first part can be unified because we can always use $(NM) instead
of "$(OBJDUMP) -h" to dump the symbols.

Split the code into the two macros, cmd_gen_symversions_c and
cmd_modversions.

Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
Reviewed-by: default avatarNick Desaulniers <ndesaulniers@google.com>
parent 79f646e8

scripts/Makefile.build

+11 −14
Original line number Diff line number Diff line
@@ -168,29 +168,25 @@ ifdef CONFIG_MODVERSIONS 
#   the actual value of the checksum generated by genksyms

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



ifdef CONFIG_LTO_CLANG

# Generate .o.symversions files for each .o with exported symbols, and link these

# to the kernel and/or modules at the end.

cmd_modversions_c =								\

gen_symversions =								\

	if $(NM) $@ 2>/dev/null | grep -q __ksymtab; then			\

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

		$(call cmd_gensymtypes_$(1),$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \

		    > $@.symversions;						\

	else									\

		rm -f $@.symversions;						\

	fi;

else

cmd_modversions_c =								\

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

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

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

										\

	fi



cmd_gen_symversions_c =	$(call gen_symversions,c)



cmd_modversions =								\

	if [ -r $@.symversions ]; then						\

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

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

			-T $@.symversions;					\

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

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

	fi

endif

endif



ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT

# compiler will not generate __mcount_loc use recordmcount or recordmcount.pl
@@ -271,7 +267,8 @@ define rule_cc_o_c 
	$(call cmd,checksrc)

	$(call cmd,checkdoc)

	$(call cmd,gen_objtooldep)

	$(call cmd,modversions_c)

	$(call cmd,gen_symversions_c)

	$(if $(CONFIG_LTO_CLANG),,$(call cmd,modversions))

	$(call cmd,record_mcount)

endef