kbuild: remove headers_{install,check}_all

headers_install_all does not make much sense any more because different
architectures export different set of uapi/linux/ headers. As you see
in include/uapi/linux/Kbuild, the installation of a.out.h, kvm.h, and
kvm_para.h is arch-dependent. So, headers_install_all repeats the
installation/removal of them.

If somebody really thinks it is useful to do headers_install for all
architectures, it would be possible by small shell-scripting, but
the top Makefile does not have to provide entry targets just for that
purpose.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>

Documentation/kbuild/headers_install.txt

@@ -39,12 +39,5 @@ INSTALL_HDR_PATH indicates where to install the headers. It defaults to
 An 'include' directory is automatically created inside INSTALL_HDR_PATH and
 headers are installed in 'INSTALL_HDR_PATH/include'.
 
-The command "make headers_install_all" exports headers for all architectures
-simultaneously.  (This is mostly of interest to distribution maintainers,
-who create an architecture-independent tarball from the resulting include
-directory.)  You also can use HDR_ARCH_LIST to specify list of architectures.
-Remember to provide the appropriate linux/asm directory via "mv" or "ln -s"
-before building a C library with headers exported this way.
-
 The kernel header export infrastructure is maintained by David Woodhouse
 <dwmw2@infradead.org>.

Documentation/kbuild/makefiles.txt

@@ -897,11 +897,7 @@ When kbuild executes, the following steps are followed (roughly):
 --- 6.2 Add prerequisites to archheaders:
 
 	The archheaders: rule is used to generate header files that
-	may be installed into user space by "make header_install" or
+	may be installed into user space by "make header_install".
-	"make headers_install_all".  In order to support
-	"make headers_install_all", this target has to be able to run
-	on an unconfigured tree, or a tree configured for another
-	architecture.
 
 	It is run before "make archprepare" when run on the
 	architecture itself.

Makefile

@@ -1181,34 +1181,23 @@ headerdep:
 #Default location for installed headers
 export INSTALL_HDR_PATH = $(objtree)/usr
 
-# If we do an all arch process set dst to include/arch-$(SRCARCH)
-hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(SRCARCH), dst=include)
-
 PHONY += archheaders archscripts
 
 PHONY += __headers
 __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
 	$(Q)$(MAKE) $(build)=scripts build_unifdef
 
-PHONY += headers_install_all
-headers_install_all:
-	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
-
 PHONY += headers_install
 headers_install: __headers
 	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
 	  $(error Headers not exportable for the $(SRCARCH) architecture))
 	$(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
-	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst)
+	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi dst=include
-
-PHONY += headers_check_all
-headers_check_all: headers_install_all
-	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
 
 PHONY += headers_check
 headers_check: headers_install
 	$(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
-	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1
+	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi dst=include HDRCHECK=1
 
 ifdef CONFIG_HEADERS_CHECK
 all: headers_check

scripts/headers.sh

@@ -1,29 +0,0 @@
-#!/bin/sh
-# SPDX-License-Identifier: GPL-2.0
-# Run headers_$1 command for all suitable architectures
-
-# Stop on error
-set -e
-
-do_command()
-{
-	if [ -f ${srctree}/arch/$2/include/asm/Kbuild ]; then
-		make ARCH=$2 KBUILD_HEADERS=$1 headers_$1
-	else
-		printf "Ignoring arch: %s\n" ${arch}
-	fi
-}
-
-archs=${HDR_ARCH_LIST:-$(ls ${srctree}/arch)}
-
-for arch in ${archs}; do
-	case ${arch} in
-	um)        # no userspace export
-		;;
-	*)
-		if [ -d ${srctree}/arch/${arch} ]; then
-			do_command $1 ${arch}
-		fi
-		;;
-	esac
-done