kbuild: simplify single target rules

The dependency will be checked anyway after Kbuild descends into a
sub-directory. Skip object/source dependency checks in top Makefile.

VPATH can be simpler since the top Makefile no longer checks the
presence of the source file, which is located in in the external
module directory.

One good thing is, it can compile an object from a generated source
file.

  $ make crypto/rsapubkey.asn1.o
    ...
  ASN.1   crypto/rsapubkey.asn1.c
  CC      crypto/rsapubkey.asn1.o

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This commit is contained in:
Masahiro Yamada 2019-02-22 16:40:09 +09:00
parent b999923c29
commit 6b12de69ad

View File

@ -219,7 +219,7 @@ objtree := .
src := $(srctree)
obj := $(objtree)
VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
VPATH := $(srctree)
export srctree objtree VPATH
@ -1699,31 +1699,23 @@ tools/%: FORCE
# target-dir => where to store outputfile
# build-dir => directory in kernel source tree to use
ifeq ($(KBUILD_EXTMOD),)
build-dir = $(patsubst %/,%,$(dir $@))
target-dir = $(dir $@)
else
zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
endif
build-target = $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD)/)$@
build-dir = $(patsubst %/,%,$(dir $(build-target)))
%.s: %.c prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
%.i: %.c prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
%.o: %.c prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
%.lst: %.c prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
%.s: %.S prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
%.o: %.S prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
%.symtypes: %.c prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
%.ll: %.c prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
%.i: prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
%.ll: prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
%.lst: prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
%.o: prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
%.s: prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
%.symtypes: prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
%.ko: %.o
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
# Modules
PHONY += /
@ -1733,9 +1725,6 @@ PHONY += /
Documentation/ samples/: headers_install
%/: prepare FORCE
$(Q)$(MAKE) KBUILD_MODULES=1 $(build)=$(build-dir)
%.ko: prepare FORCE
$(Q)$(MAKE) $(build)=$(build-dir) $(@:.ko=.o)
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
# FIXME Should go into a make.lib or something
# ===========================================================================