kbuild: rename hostprogs-y/always to hostprogs/always-y

In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.

It is typically useful in scripts/Makefile because it allows Kbuild to
selectively compile host programs based on the kernel configuration.

This commit renames like follows:

  always       ->  always-y
  hostprogs-y  ->  hostprogs

So, scripts/Makefile will look like this:

  always-$(CONFIG_BUILD_BIN2C) += ...
  always-$(CONFIG_KALLSYMS)    += ...
      ...
  hostprogs := $(always-y) $(always-m)

I think this makes more sense because a host program is always a host
program, irrespective of the kernel configuration. We want to specify
which ones to compile by CONFIG options, so always-y will be handier.

The "always", "hostprogs-y", "hostprogs-m" will be kept for backward
compatibility for a while.

Signed-off-by: Masahiro Yamada <[email protected]>

Author: masahir0y

Documentation/kbuild/makefiles.rst

@@ -28,7 +28,6 @@ This document describes the Linux kernel Makefiles.
 	   --- 4.3 Using C++ for host programs
 	   --- 4.4 Controlling compiler options for host programs
 	   --- 4.5 When host programs are actually built
-	   --- 4.6 Using hostprogs-$(CONFIG_FOO)
 
 	=== 5 Kbuild clean infrastructure
 
@@ -595,11 +594,11 @@ compilation stage.
 Two steps are required in order to use a host executable.
 
 The first step is to tell kbuild that a host program exists. This is
-done utilising the variable hostprogs-y.
+done utilising the variable "hostprogs".
 
 The second step is to add an explicit dependency to the executable.
 This can be done in two ways. Either add the dependency in a rule,
-or utilise the variable $(always).
+or utilise the variable "always-y".
 Both possibilities are described in the following.
 
 4.1 Simple Host Program
@@ -612,7 +611,7 @@ Both possibilities are described in the following.
 
 	Example::
 
-		hostprogs-y := bin2hex
+		hostprogs := bin2hex
 
 	Kbuild assumes in the above example that bin2hex is made from a single
 	c-source file named bin2hex.c located in the same directory as
@@ -630,7 +629,7 @@ Both possibilities are described in the following.
 	Example::
 
 		#scripts/lxdialog/Makefile
-		hostprogs-y   := lxdialog
+		hostprogs     := lxdialog
 		lxdialog-objs := checklist.o lxdialog.o
 
 	Objects with extension .o are compiled from the corresponding .c
@@ -650,7 +649,7 @@ Both possibilities are described in the following.
 	Example::
 
 		#scripts/kconfig/Makefile
-		hostprogs-y   := qconf
+		hostprogs     := qconf
 		qconf-cxxobjs := qconf.o
 
 	In the example above the executable is composed of the C++ file
@@ -662,7 +661,7 @@ Both possibilities are described in the following.
 	Example::
 
 		#scripts/kconfig/Makefile
-		hostprogs-y   := qconf
+		hostprogs     := qconf
 		qconf-cxxobjs := qconf.o
 		qconf-objs    := check.o
 
@@ -710,55 +709,39 @@ Both possibilities are described in the following.
 	Example::
 
 		#drivers/pci/Makefile
-		hostprogs-y := gen-devlist
+		hostprogs := gen-devlist
 		$(obj)/devlist.h: $(src)/pci.ids $(obj)/gen-devlist
 			( cd $(obj); ./gen-devlist ) < $<
 
 	The target $(obj)/devlist.h will not be built before
 	$(obj)/gen-devlist is updated. Note that references to
 	the host programs in special rules must be prefixed with $(obj).
 
-	(2) Use $(always)
+	(2) Use always-y
 
 	When there is no suitable special rule, and the host program
-	shall be built when a makefile is entered, the $(always)
+	shall be built when a makefile is entered, the always-y
 	variable shall be used.
 
 	Example::
 
 		#scripts/lxdialog/Makefile
-		hostprogs-y   := lxdialog
-		always        := $(hostprogs-y)
+		hostprogs     := lxdialog
+		always-y      := $(hostprogs)
 
 	This will tell kbuild to build lxdialog even if not referenced in
 	any rule.
 
-4.6 Using hostprogs-$(CONFIG_FOO)
----------------------------------
-
-	A typical pattern in a Kbuild file looks like this:
-
-	Example::
-
-		#scripts/Makefile
-		hostprogs-$(CONFIG_KALLSYMS) += kallsyms
-
-	Kbuild knows about both 'y' for built-in and 'm' for module.
-	So if a config symbol evaluates to 'm', kbuild will still build
-	the binary. In other words, Kbuild handles hostprogs-m exactly
-	like hostprogs-y. But only hostprogs-y is recommended to be used
-	when no CONFIG symbols are involved.
-
 5 Kbuild clean infrastructure
 =============================
 
 "make clean" deletes most generated files in the obj tree where the kernel
 is compiled. This includes generated files such as host programs.
-Kbuild knows targets listed in $(hostprogs-y), $(hostprogs-m), $(always),
-$(extra-y) and $(targets). They are all deleted during "make clean".
-Files matching the patterns "*.[oas]", "*.ko", plus some additional files
-generated by kbuild are deleted all over the kernel src tree when
-"make clean" is executed.
+Kbuild knows targets listed in $(hostprogs), $(always-y), $(always-m),
+$(always-), $(extra-y), $(extra-) and $(targets). They are all deleted
+during "make clean". Files matching the patterns "*.[oas]", "*.ko", plus
+some additional files generated by kbuild are deleted all over the kernel
+source tree when "make clean" is executed.
 
 Additional files or directories can be specified in kbuild makefiles by use of
 $(clean-files).

Kbuild

@@ -7,7 +7,7 @@
 
 bounds-file := include/generated/bounds.h
 
-always  := $(bounds-file)
+always-y := $(bounds-file)
 targets := kernel/bounds.s
 
 $(bounds-file): kernel/bounds.s FORCE
@@ -28,7 +28,7 @@ $(timeconst-file): kernel/time/timeconst.bc FORCE
 
 offsets-file := include/generated/asm-offsets.h
 
-always  += $(offsets-file)
+always-y += $(offsets-file)
 targets += arch/$(SRCARCH)/kernel/asm-offsets.s
 
 arch/$(SRCARCH)/kernel/asm-offsets.s: $(timeconst-file) $(bounds-file)
@@ -39,7 +39,7 @@ $(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
 #####
 # Check for missing system calls
 
-always += missing-syscalls
+always-y += missing-syscalls
 
 quiet_cmd_syscalls = CALL    $<
       cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)
@@ -50,7 +50,7 @@ missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
 #####
 # Check atomic headers are up-to-date
 
-always += old-atomics
+always-y += old-atomics
 
 quiet_cmd_atomics = CALL    $<
       cmd_atomics = $(CONFIG_SHELL) $<

arch/alpha/boot/Makefile

@@ -8,7 +8,7 @@
 # Copyright (C) 1994 by Linus Torvalds
 #
 
-hostprogs-y	:= tools/mkbb tools/objstrip
+hostprogs	:= tools/mkbb tools/objstrip
 targets		:= vmlinux.gz vmlinux \
 		   vmlinux.nh tools/lxboot tools/bootlx tools/bootph \
 		   tools/bootpzh bootloader bootpheader bootpzheader 

arch/arm/vdso/Makefile

@@ -5,7 +5,7 @@
 ARCH_REL_TYPE_ABS := R_ARM_JUMP_SLOT|R_ARM_GLOB_DAT|R_ARM_ABS32
 include $(srctree)/lib/vdso/Makefile
 
-hostprogs-y := vdsomunge
+hostprogs := vdsomunge
 
 obj-vdso := vgettimeofday.o datapage.o note.o
 

arch/arm64/kernel/vdso32/Makefile

@@ -115,9 +115,9 @@ VDSO_LDFLAGS += $(call cc32-ldoption,-fuse-ld=bfd)
 
 # Borrow vdsomunge.c from the arm vDSO
 # We have to use a relative path because scripts/Makefile.host prefixes
-# $(hostprogs-y) with $(obj)
+# $(hostprogs) with $(obj)
 munge := ../../../arm/vdso/vdsomunge
-hostprogs-y := $(munge)
+hostprogs := $(munge)
 
 c-obj-vdso := note.o
 c-obj-vdso-gettimeofday := vgettimeofday.o

arch/mips/boot/Makefile

@@ -21,7 +21,7 @@ endif
 drop-sections := .reginfo .mdebug .comment .note .pdr .options .MIPS.options
 strip-flags   := $(addprefix --remove-section=,$(drop-sections))
 
-hostprogs-y := elf2ecoff
+hostprogs := elf2ecoff
 
 suffix-y			:= bin
 suffix-$(CONFIG_KERNEL_BZIP2)	:= bz2

arch/mips/boot/compressed/Makefile

@@ -84,7 +84,7 @@ $(obj)/piggy.o: $(obj)/dummy.o $(obj)/vmlinux.bin.z FORCE
 HOSTCFLAGS_calc_vmlinuz_load_addr.o += $(LINUXINCLUDE)
 
 # Calculate the load address of the compressed kernel image
-hostprogs-y := calc_vmlinuz_load_addr
+hostprogs := calc_vmlinuz_load_addr
 
 ifneq ($(zload-y),)
 VMLINUZ_LOAD_ADDRESS := $(zload-y)
@@ -112,7 +112,7 @@ ifdef CONFIG_MACH_DECSTATION
 endif
 
 # elf2ecoff can only handle 32bit image
-hostprogs-y += ../elf2ecoff
+hostprogs += ../elf2ecoff
 
 ifdef CONFIG_32BIT
 	VMLINUZ = vmlinuz

arch/mips/boot/tools/Makefile

@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 
-hostprogs-y	+= relocs
+hostprogs	+= relocs
 relocs-objs	+= relocs_32.o
 relocs-objs	+= relocs_64.o
 relocs-objs	+= relocs_main.o

arch/mips/tools/Makefile

@@ -1,10 +1,10 @@
 # SPDX-License-Identifier: GPL-2.0
-hostprogs-y := elf-entry
+hostprogs := elf-entry
 PHONY += elf-entry
 elf-entry: $(obj)/elf-entry
 	@:
 
-hostprogs-$(CONFIG_CPU_LOONGSON3_WORKAROUNDS) += loongson3-llsc-check
+hostprogs += loongson3-llsc-check
 PHONY += loongson3-llsc-check
 loongson3-llsc-check: $(obj)/loongson3-llsc-check
 	@:

arch/mips/vdso/Makefile

@@ -100,7 +100,7 @@ $(obj)/%.so.raw: OBJCOPYFLAGS := -S
 $(obj)/%.so.raw: $(obj)/%.so.dbg.raw FORCE
 	$(call if_changed,objcopy)
 
-hostprogs-y := genvdso
+hostprogs := genvdso
 
 quiet_cmd_genvdso = GENVDSO $@
 define cmd_genvdso