kbuild: Don't reset timestamps in include/generated if not needed

Use filechk to generate asm-offsets.h and bounds.h. Based on a patch by
Valdis Kletnieks.

Reported-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Acked-By: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
This commit is contained in:
Michal Marek 2015-03-11 11:01:01 +01:00
parent c517d838eb
commit 70a4fd6c56

18
Kbuild
View File

@ -13,8 +13,9 @@ define sed-y
s:->::; p;}"
endef
quiet_cmd_offsets = GEN $@
define cmd_offsets
# Use filechk to avoid rebuilds when a header changes, but the resulting file
# does not
define filechk_offsets
(set -e; \
echo "#ifndef $2"; \
echo "#define $2"; \
@ -24,9 +25,9 @@ define cmd_offsets
echo " * This file was generated by Kbuild"; \
echo " */"; \
echo ""; \
sed -ne $(sed-y) $<; \
sed -ne $(sed-y); \
echo ""; \
echo "#endif" ) > $@
echo "#endif" )
endef
#####
@ -42,9 +43,8 @@ kernel/bounds.s: kernel/bounds.c FORCE
$(Q)mkdir -p $(dir $@)
$(call if_changed_dep,cc_s_c)
$(obj)/$(bounds-file): kernel/bounds.s Kbuild
$(Q)mkdir -p $(dir $@)
$(call cmd,offsets,__LINUX_BOUNDS_H__)
$(obj)/$(bounds-file): kernel/bounds.s FORCE
$(call filechk,offsets,__LINUX_BOUNDS_H__)
#####
# 2) Generate asm-offsets.h
@ -62,8 +62,8 @@ arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c \
$(Q)mkdir -p $(dir $@)
$(call if_changed_dep,cc_s_c)
$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s Kbuild
$(call cmd,offsets,__ASM_OFFSETS_H__)
$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
$(call filechk,offsets,__ASM_OFFSETS_H__)
#####
# 3) Check for missing system calls