The previous commit largely optimized the object directory creation. We can optimize it more for incremental build. There are already *.cmd files in the output directory. The existing *.cmd files have been picked up by $(wildcard ...). Obviously, directories containing them exist too, so we can skip "mkdir -p". With this, Kbuild runs almost zero "mkdir -p" in incremental building. Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> --- scripts/Makefile.build | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 89ac180..90ea7a5 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -583,8 +583,13 @@ endif ifneq ($(KBUILD_SRC),) # Create directories for object files if directory does not exist obj-dirs := $(sort $(obj) $(patsubst %/,%, $(dir $(targets)))) +# If cmd_files exist, their directories apparently exist. Skip mkdir. +exist-dirs := $(sort $(patsubst %/,%, $(dir $(cmd_files)))) +obj-dirs := $(strip $(filter-out . $(exist-dirs), $(obj-dirs))) +ifneq ($(obj-dirs),) $(shell mkdir -p $(obj-dirs)) endif +endif # Declare the contents of the .PHONY variable as phony. We keep that # information in a variable se we can use it in if_changed and friends. -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html