kbuild: generate modules.builtin

To make it easier for module-init-tools and scripts like mkinitrd to
distinguish builtin and missing modules, install a modules.builtin file
listing all builtin modules. This is done by generating an additional
config file (tristate.conf) with tristate options set to uppercase 'Y'
or 'M'. If we source that config file, the builtin modules appear in
obj-Y.

Signed-off-by: Michal Marek <mmarek@suse.cz>

1 files changed, 10 insertions, 4 deletions

diff --git a/Makefile b/Makefile
index aa608c2959f5..391fcb396324 100644
--- a/Makefile
+++ b/Makefile
@@ -464,7 +464,7 @@ ifeq ($(KBUILD_EXTMOD),)
 # Carefully list dependencies so we do not try to build scripts twice
 # in parallel
 PHONY += scripts
-scripts: scripts_basic include/config/auto.conf
+scripts: scripts_basic include/config/auto.conf include/config/tristate.conf
         $(Q)$(MAKE) $(build)=$(@)
 
 # Objects we will link into vmlinux / subdirs we need to visit
@@ -491,7 +491,7 @@ $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
 # with it and forgot to run make oldconfig.
 # if auto.conf.cmd is missing then we are probably in a cleaned tree so
 # we execute the config step to be sure to catch updated Kconfig files
-include/config/auto.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
+include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
         $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
 else
 # external modules needs include/generated/autoconf.h and include/config/auto.conf
@@ -876,6 +876,9 @@ $(sort $(vmlinux-init) $(vmlinux-main)) $(vmlinux-lds): $(vmlinux-dirs) ;
 PHONY += $(vmlinux-dirs)
 $(vmlinux-dirs): prepare scripts
         $(Q)$(MAKE) $(build)=$@
+ifdef CONFIG_MODULES
+        $(Q)$(MAKE) $(modbuiltin)=$@
+endif
 
 # Build the kernel release string
 #
@@ -1080,6 +1083,7 @@ all: modules
 PHONY += modules
 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux)
         $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
+        $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.builtin) > $(objtree)/modules.builtin
         @$(kecho) '  Building modules, stage 2.';
         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modbuild
@@ -1109,6 +1113,7 @@ _modinst_:
                 ln -s $(objtree) $(MODLIB)/build ; \
         fi
         @cp -f $(objtree)/modules.order $(MODLIB)/
+        @cp -f $(objtree)/modules.builtin $(MODLIB)/
         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
 
 # This depmod is only for convenience to give the initial
@@ -1169,7 +1174,7 @@ clean: archclean $(clean-dirs)
                 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
                 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
                 -o -name '*.symtypes' -o -name 'modules.order' \
-                -o -name '.tmp_*.o.*' \
+                -o modules.order -o -name '.tmp_*.o.*' \
                 -o -name '*.gcno' \) -type f -print | xargs rm -f
 
 # mrproper - Delete all generated files, including .config
@@ -1367,7 +1372,8 @@ $(clean-dirs):
 
 clean:  rm-dirs := $(MODVERDIR)
 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers \
-                   $(KBUILD_EXTMOD)/modules.order
+                   $(KBUILD_EXTMOD)/modules.order \
+                   $(KBUILD_EXTMOD)/modules.builtin
 clean: $(clean-dirs)
         $(call cmd,rmdirs)
         $(call cmd,rmfiles)