From: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> commit b1fbfcb4a20949df08dd995927cdc5ad220c128d upstream. Commit 2dffd23f81a3 ("kbuild: make single target builds much faster") made the situation much better. To improve it even more, apply the similar idea to the top Makefile. Trim unrelated directories from build-dirs. The single build code must be moved above the 'descend' target. Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> Tested-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- Makefile | 90 ++++++++++++++++++++++++++++++++------------------------------- 1 file changed, 47 insertions(+), 43 deletions(-) --- a/Makefile +++ b/Makefile @@ -1635,6 +1635,50 @@ help: PHONY += prepare endif # KBUILD_EXTMOD +# Single targets +# --------------------------------------------------------------------------- +# To build individual files in subdirectories, you can do like this: +# +# make foo/bar/baz.s +# +# The supported suffixes for single-target are listed in 'single-targets' +# +# To build only under specific subdirectories, you can do like this: +# +# make foo/bar/baz/ + +ifdef single-build + +# .ko is special because modpost is needed +single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS))) +single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS))) + +$(single-ko): single_modpost + @: +$(single-no-ko): descend + @: + +ifeq ($(KBUILD_EXTMOD),) +# For the single build of in-tree modules, use a temporary file to avoid +# the situation of modules_install installing an invalid modules.order. +MODORDER := .modules.tmp +endif + +PHONY += single_modpost +single_modpost: $(single-no-ko) + $(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER) + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost + +KBUILD_MODULES := 1 + +export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko)) + +# trim unrelated directories +build-dirs := $(foreach d, $(build-dirs), \ + $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d))) + +endif + # Handle descending into subdirectories listed in $(build-dirs) # Preset locale variables to speed up the build process. Limit locale # tweaks to this spot to avoid wrong language settings when running @@ -1643,7 +1687,9 @@ endif # KBUILD_EXTMOD PHONY += descend $(build-dirs) descend: $(build-dirs) $(build-dirs): prepare - $(Q)$(MAKE) $(build)=$@ single-build=$(single-build) need-builtin=1 need-modorder=1 + $(Q)$(MAKE) $(build)=$@ \ + single-build=$(if $(filter-out $@/, $(single-no-ko)),1) \ + need-builtin=1 need-modorder=1 clean-dirs := $(addprefix _clean_, $(clean-dirs)) PHONY += $(clean-dirs) clean @@ -1747,48 +1793,6 @@ tools/%: FORCE $(Q)mkdir -p $(objtree)/tools $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $* -# Single targets -# --------------------------------------------------------------------------- -# To build individual files in subdirectories, you can do like this: -# -# make foo/bar/baz.s -# -# The supported suffixes for single-target are listed in 'single-targets' -# -# To build only under specific subdirectories, you can do like this: -# -# make foo/bar/baz/ - -ifdef single-build - -# .ko is special because modpost is needed -single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS))) -single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS))) - -$(single-ko): single_modpost - @: -$(single-no-ko): descend - @: - -ifeq ($(KBUILD_EXTMOD),) -# For the single build of in-tree modules, use a temporary file to avoid -# the situation of modules_install installing an invalid modules.order. -MODORDER := .modules.tmp -endif - -PHONY += single_modpost -single_modpost: $(single-no-ko) - $(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER) - $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost - -KBUILD_MODULES := 1 - -export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko)) - -single-build = $(if $(filter-out $@/, $(single-no-ko)),1) - -endif - # FIXME Should go into a make.lib or something # ===========================================================================