[PATCH 6.1 134/280] kconfig: refactor Makefile to reduce process forks

Greg Kroah-Hartman
2026-02-04T15:10:34Z

From: Masahiro Yamada <masahiroy@kernel.org>

[ Upstream commit 3122c84409d578a5df8bcb1953547e0b871ac4c2 ]

Refactor Makefile and use read-file macro. For Make >= 4.2, it can read
out a file by using the built-in function.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Stable-dep-of: baaecfcac559 ("kconfig: fix static linking of nconf")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
scripts/kconfig/.gitignore | 4 +++-
scripts/kconfig/Makefile | 45 +++++++++++++++++++-----------------
scripts/kconfig/gconf-cfg.sh | 7 ++++--
scripts/kconfig/mconf-cfg.sh | 25 +++++++++++---------
scripts/kconfig/nconf-cfg.sh | 23 ++++++++++--------
scripts/kconfig/qconf-cfg.sh | 10 +++++---
scripts/remove-stale-files | 2 ++
7 files changed, 68 insertions(+), 48 deletions(-)

diff --git a/scripts/kconfig/.gitignore b/scripts/kconfig/.gitignore
index 500e7424b3ef9..c8a3f9cd52f02 100644
--- a/scripts/kconfig/.gitignore
+++ b/scripts/kconfig/.gitignore
@@ -1,5 +1,7 @@
# SPDX-License-Identifier: GPL-2.0-only
/conf
/[gmnq]conf
-/[gmnq]conf-cfg
+/[gmnq]conf-cflags
+/[gmnq]conf-libs
+/qconf-bin
/qconf-moc.cc
diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index b8ef0fb4bbef7..0b1d15efaeb0c 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -159,11 +159,12 @@ conf-objs := conf.o $(common-objs)
hostprogs += nconf
nconf-objs := nconf.o nconf.gui.o $(common-objs)

-HOSTLDLIBS_nconf = $(shell . $(obj)/nconf-cfg && echo $$libs)
-HOSTCFLAGS_nconf.o = $(shell . $(obj)/nconf-cfg && echo $$cflags)
-HOSTCFLAGS_nconf.gui.o = $(shell . $(obj)/nconf-cfg && echo $$cflags)
+HOSTLDLIBS_nconf = $(call read-file, $(obj)/nconf-libs)
+HOSTCFLAGS_nconf.o = $(call read-file, $(obj)/nconf-cflags)
+HOSTCFLAGS_nconf.gui.o = $(call read-file, $(obj)/nconf-cflags)

-$(obj)/nconf.o $(obj)/nconf.gui.o: $(obj)/nconf-cfg
+$(obj)/nconf: | $(obj)/nconf-libs
+$(obj)/nconf.o $(obj)/nconf.gui.o: | $(obj)/nconf-cflags

# mconf: Used for the menuconfig target based on lxdialog
hostprogs += mconf
@@ -171,27 +172,28 @@ lxdialog := $(addprefix lxdialog/, \
checklist.o inputbox.o menubox.o textbox.o util.o yesno.o)
mconf-objs := mconf.o $(lxdialog) $(common-objs)

-HOSTLDLIBS_mconf = $(shell . $(obj)/mconf-cfg && echo $$libs)
+HOSTLDLIBS_mconf = $(call read-file, $(obj)/mconf-libs)
$(foreach f, mconf.o $(lxdialog), \
- $(eval HOSTCFLAGS_$f = $$(shell . $(obj)/mconf-cfg && echo $$$$cflags)))
+ $(eval HOSTCFLAGS_$f = $$(call read-file, $(obj)/mconf-cflags)))

-$(addprefix $(obj)/, mconf.o $(lxdialog)): $(obj)/mconf-cfg
+$(obj)/mconf: | $(obj)/mconf-libs
+$(addprefix $(obj)/, mconf.o $(lxdialog)): | $(obj)/mconf-cflags

# qconf: Used for the xconfig target based on Qt
hostprogs += qconf
qconf-cxxobjs := qconf.o qconf-moc.o
qconf-objs := images.o $(common-objs)

-HOSTLDLIBS_qconf = $(shell . $(obj)/qconf-cfg && echo $$libs)
-HOSTCXXFLAGS_qconf.o = $(shell . $(obj)/qconf-cfg && echo $$cflags)
-HOSTCXXFLAGS_qconf-moc.o = $(shell . $(obj)/qconf-cfg && echo $$cflags)
-
-$(obj)/qconf.o: $(obj)/qconf-cfg
+HOSTLDLIBS_qconf = $(call read-file, $(obj)/qconf-libs)
+HOSTCXXFLAGS_qconf.o = -std=c++11 -fPIC $(call read-file, $(obj)/qconf-cflags)
+HOSTCXXFLAGS_qconf-moc.o = -std=c++11 -fPIC $(call read-file, $(obj)/qconf-cflags)
+$(obj)/qconf: | $(obj)/qconf-libs
+$(obj)/qconf.o $(obj)/qconf-moc.o: | $(obj)/qconf-cflags

quiet_cmd_moc = MOC $@
- cmd_moc = $(shell . $(obj)/qconf-cfg && echo $$moc) $< -o $@
+ cmd_moc = $(call read-file, $(obj)/qconf-bin)/moc $< -o $@

-$(obj)/qconf-moc.cc: $(src)/qconf.h $(obj)/qconf-cfg FORCE
+$(obj)/qconf-moc.cc: $(src)/qconf.h FORCE | $(obj)/qconf-bin
$(call if_changed,moc)

targets += qconf-moc.cc
@@ -200,15 +202,16 @@ targets += qconf-moc.cc
hostprogs += gconf
gconf-objs := gconf.o images.o $(common-objs)

-HOSTLDLIBS_gconf = $(shell . $(obj)/gconf-cfg && echo $$libs)
-HOSTCFLAGS_gconf.o = $(shell . $(obj)/gconf-cfg && echo $$cflags)
+HOSTLDLIBS_gconf = $(call read-file, $(obj)/gconf-libs)
+HOSTCFLAGS_gconf.o = $(call read-file, $(obj)/gconf-cflags)

-$(obj)/gconf.o: $(obj)/gconf-cfg
+$(obj)/gconf: | $(obj)/gconf-libs
+$(obj)/gconf.o: | $(obj)/gconf-cflags

# check if necessary packages are available, and configure build flags
-filechk_conf_cfg = $(CONFIG_SHELL) $<
+cmd_conf_cfg = $< $(addprefix $(obj)/$*conf-, cflags libs bin)

-$(obj)/%conf-cfg: $(src)/%conf-cfg.sh FORCE
- $(call filechk,conf_cfg)
+$(obj)/%conf-cflags $(obj)/%conf-libs $(obj)/%conf-bin: $(src)/%conf-cfg.sh
+ $(call cmd,conf_cfg)

-clean-files += *conf-cfg
+clean-files += *conf-cflags *conf-libs *conf-bin
diff --git a/scripts/kconfig/gconf-cfg.sh b/scripts/kconfig/gconf-cfg.sh
index cbd90c28c05f2..040d8f3388202 100755
--- a/scripts/kconfig/gconf-cfg.sh
+++ b/scripts/kconfig/gconf-cfg.sh
@@ -1,6 +1,9 @@
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0

+cflags=$1
+libs=$2
+
PKG="gtk+-2.0 gmodule-2.0 libglade-2.0"

if [ -z "$(command -v ${HOSTPKG_CONFIG})" ]; then
@@ -26,5 +29,5 @@ if ! ${HOSTPKG_CONFIG} --atleast-version=2.0.0 gtk+-2.0; then
exit 1
fi

-echo cflags=\"$(${HOSTPKG_CONFIG} --cflags $PKG)\"
-echo libs=\"$(${HOSTPKG_CONFIG} --libs $PKG)\"
+${HOSTPKG_CONFIG} --cflags ${PKG} > ${cflags}
+${HOSTPKG_CONFIG} --libs ${PKG} > ${libs}
diff --git a/scripts/kconfig/mconf-cfg.sh b/scripts/kconfig/mconf-cfg.sh
index 025b565e0b7cd..1e61f50a59050 100755
--- a/scripts/kconfig/mconf-cfg.sh
+++ b/scripts/kconfig/mconf-cfg.sh
@@ -1,19 +1,22 @@
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0

+cflags=$1
+libs=$2
+
PKG="ncursesw"
PKG2="ncurses"

if [ -n "$(command -v ${HOSTPKG_CONFIG})" ]; then
if ${HOSTPKG_CONFIG} --exists $PKG; then
- echo cflags=\"$(${HOSTPKG_CONFIG} --cflags $PKG)\"
- echo libs=\"$(${HOSTPKG_CONFIG} --libs $PKG)\"
+ ${HOSTPKG_CONFIG} --cflags ${PKG} > ${cflags}
+ ${HOSTPKG_CONFIG} --libs ${PKG} > ${libs}
exit 0
fi

- if ${HOSTPKG_CONFIG} --exists $PKG2; then
- echo cflags=\"$(${HOSTPKG_CONFIG} --cflags $PKG2)\"
- echo libs=\"$(${HOSTPKG_CONFIG} --libs $PKG2)\"
+ if ${HOSTPKG_CONFIG} --exists ${PKG2}; then
+ ${HOSTPKG_CONFIG} --cflags ${PKG2} > ${cflags}
+ ${HOSTPKG_CONFIG} --libs ${PKG2} > ${libs}
exit 0
fi
fi
@@ -22,22 +25,22 @@ fi
# (Even if it is installed, some distributions such as openSUSE cannot
# find ncurses by pkg-config.)
if [ -f /usr/include/ncursesw/ncurses.h ]; then
- echo cflags=\"-D_GNU_SOURCE -I/usr/include/ncursesw\"
- echo libs=\"-lncursesw\"
+ echo -D_GNU_SOURCE -I/usr/include/ncursesw > ${cflags}
+ echo -lncursesw > ${libs}
exit 0
fi

if [ -f /usr/include/ncurses/ncurses.h ]; then
- echo cflags=\"-D_GNU_SOURCE -I/usr/include/ncurses\"
- echo libs=\"-lncurses\"
+ echo -D_GNU_SOURCE -I/usr/include/ncurses > ${cflags}
+ echo -lncurses > ${libs}
exit 0
fi

# As a final fallback before giving up, check if $HOSTCC knows of a default
# ncurses installation (e.g. from a vendor-specific sysroot).
if echo '#include <ncurses.h>' | ${HOSTCC} -E - >/dev/null 2>&1; then
- echo cflags=\"-D_GNU_SOURCE\"
- echo libs=\"-lncurses\"
+ echo -D_GNU_SOURCE > ${cflags}
+ echo -lncurses > ${libs}
exit 0
fi

diff --git a/scripts/kconfig/nconf-cfg.sh b/scripts/kconfig/nconf-cfg.sh
index 3a10bac2adb3a..f871a2160e363 100755
--- a/scripts/kconfig/nconf-cfg.sh
+++ b/scripts/kconfig/nconf-cfg.sh
@@ -1,19 +1,22 @@
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0

+cflags=$1
+libs=$2
+
PKG="ncursesw menuw panelw"
PKG2="ncurses menu panel"

if [ -n "$(command -v ${HOSTPKG_CONFIG})" ]; then
if ${HOSTPKG_CONFIG} --exists $PKG; then
- echo cflags=\"$(${HOSTPKG_CONFIG} --cflags $PKG)\"
- echo libs=\"$(${HOSTPKG_CONFIG} --libs $PKG)\"
+ ${HOSTPKG_CONFIG} --cflags ${PKG} > ${cflags}
+ ${HOSTPKG_CONFIG} --libs ${PKG} > ${libs}
exit 0
fi

if ${HOSTPKG_CONFIG} --exists $PKG2; then
- echo cflags=\"$(${HOSTPKG_CONFIG} --cflags $PKG2)\"
- echo libs=\"$(${HOSTPKG_CONFIG} --libs $PKG2)\"
+ ${HOSTPKG_CONFIG} --cflags ${PKG2} > ${cflags}
+ ${HOSTPKG_CONFIG} --libs ${PKG2} > ${libs}
exit 0
fi
fi
@@ -22,20 +25,20 @@ fi
# (Even if it is installed, some distributions such as openSUSE cannot
# find ncurses by pkg-config.)
if [ -f /usr/include/ncursesw/ncurses.h ]; then
- echo cflags=\"-D_GNU_SOURCE -I/usr/include/ncursesw\"
- echo libs=\"-lncursesw -lmenuw -lpanelw\"
+ echo -D_GNU_SOURCE -I/usr/include/ncursesw > ${cflags}
+ echo -lncursesw -lmenuw -lpanelw > ${libs}
exit 0
fi

if [ -f /usr/include/ncurses/ncurses.h ]; then
- echo cflags=\"-D_GNU_SOURCE -I/usr/include/ncurses\"
- echo libs=\"-lncurses -lmenu -lpanel\"
+ echo -D_GNU_SOURCE -I/usr/include/ncurses > ${cflags}
+ echo -lncurses -lmenu -lpanel > ${libs}
exit 0
fi

if [ -f /usr/include/ncurses.h ]; then
- echo cflags=\"-D_GNU_SOURCE\"
- echo libs=\"-lncurses -lmenu -lpanel\"
+ echo -D_GNU_SOURCE > ${cflags}
+ echo -lncurses -lmenu -lpanel > ${libs}
exit 0
fi

diff --git a/scripts/kconfig/qconf-cfg.sh b/scripts/kconfig/qconf-cfg.sh
index ad652cb539474..117f36e568fc5 100755
--- a/scripts/kconfig/qconf-cfg.sh
+++ b/scripts/kconfig/qconf-cfg.sh
@@ -1,6 +1,10 @@
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0

+cflags=$1
+libs=$2
+bin=$3
+
PKG="Qt5Core Qt5Gui Qt5Widgets"

if [ -z "$(command -v ${HOSTPKG_CONFIG})" ]; then
@@ -11,9 +15,9 @@ if [ -z "$(command -v ${HOSTPKG_CONFIG})" ]; then
fi

if ${HOSTPKG_CONFIG} --exists $PKG; then
- echo cflags=\"-std=c++11 -fPIC $(${HOSTPKG_CONFIG} --cflags $PKG)\"
- echo libs=\"$(${HOSTPKG_CONFIG} --libs $PKG)\"
- echo moc=\"$(${HOSTPKG_CONFIG} --variable=host_bins Qt5Core)/moc\"
+ ${HOSTPKG_CONFIG} --cflags ${PKG} > ${cflags}
+ ${HOSTPKG_CONFIG} --libs ${PKG} > ${libs}
+ ${HOSTPKG_CONFIG} --variable=host_bins Qt5Core > ${bin}
exit 0
fi

diff --git a/scripts/remove-stale-files b/scripts/remove-stale-files
index ccadfa3afb2b8..64b14aa5aebf4 100755
--- a/scripts/remove-stale-files
+++ b/scripts/remove-stale-files
@@ -47,3 +47,5 @@ rm -f arch/riscv/purgatory/kexec-purgatory.c
rm -f scripts/extract-cert

rm -f arch/x86/purgatory/kexec-purgatory.c
+
+rm -f scripts/kconfig/[gmnq]conf-cfg
--
2.51.0