mirror of
https://github.com/torvalds/linux.git
synced 2024-11-23 12:42:02 +00:00
09bd7c75e5
One of the most remarkable improvements in this cycle is, Kbuild is
now able to cache the result of shell commands. Some variables are
expensive to compute, for example, $(call cc-option,...) invokes the
compiler. It is not efficient to redo this computation every time,
even when we are not actually building anything. Kbuild creates a
hidden file ".cache.mk" that contains invoked shell commands and
their results. The speed-up should be noticeable.
Summary:
- Fix arch build issues (hexagon, sh)
- Clean up various Makefiles and scripts
- Fix wrong usage of {CFLAGS,LDFLAGS}_MODULE in arch Makefiles
- Cache variables that are expensive to compute
- Improve cc-ldopton and ld-option for Clang
- Optimize output directory creation
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQIcBAABAgAGBQJaDxaLAAoJED2LAQed4NsGIHQP/isMxxaIxIAWU56+ZcII74k7
639VgrKi9n5y25d1dBRTQg+vReHE6E2JbkCqpVOu11t7m0LT7yUK8v3WwyLf1qTN
GxnqZ/WMQU5/AYVqIWo8jN4FGHpivHJ6qbeiNJM9qN4RAkzG0sZUq746VaFZYmIR
Lu0Gf4m4qjifkkhXsQdWT5i7yNTidPqaL6GNb+FcFkEHlVre8jma0kJlgfHxru84
WmETpjQXvHAZ/R61vY6ekAWpqFhw3ecJY96A9npnx+SQVQdSNAdpaU0SK29jB0ON
/SAfpHg9oa/gD0LFOKV6zkjnAkd4TEjrJEiHHhz5gjT/SbS3T1llBIGZ1oV4X7Y0
Vlh9KWlm1FJJI4SIzc9qUaQMp6JtLfEfHKJCc45xVaN3fNrDnR8jl80x5+95ELga
dCkZgnq5u82MtTysCbHBESwDYQaVPyIrh7In+mduglaCqhqj9KoDjoLoiGfCg7SA
3tPflYVd629w5l5GrazJ40jWn1+ggMtgMOVooJNJ+dINCP+GxsUpH84Ww2Pdic+/
qLdud6TeqxrZDGzWXqKNLu8alM8NGgSr101l9gIf1oqSyy63duBpMrxGDoIJS3FU
rFDoFFUhlfkAXNbQHtVGNzKtcpCjURh992j9Fa1+NfMwSce5IHkMwTvPmNSRowi8
0llLjXhD/bxK6FpdvlV8
=zIdO
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
"One of the most remarkable improvements in this cycle is, Kbuild is
now able to cache the result of shell commands. Some variables are
expensive to compute, for example, $(call cc-option,...) invokes the
compiler. It is not efficient to redo this computation every time,
even when we are not actually building anything. Kbuild creates a
hidden file ".cache.mk" that contains invoked shell commands and their
results. The speed-up should be noticeable.
Summary:
- Fix arch build issues (hexagon, sh)
- Clean up various Makefiles and scripts
- Fix wrong usage of {CFLAGS,LDFLAGS}_MODULE in arch Makefiles
- Cache variables that are expensive to compute
- Improve cc-ldopton and ld-option for Clang
- Optimize output directory creation"
* tag 'kbuild-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits)
kbuild: move coccicheck help from scripts/Makefile.help to top Makefile
sh: decompressor: add shipped files to .gitignore
frv: .gitignore: ignore vmlinux.lds
selinux: remove unnecessary assignment to subdir-
kbuild: specify FORCE in Makefile.headersinst as .PHONY target
kbuild: remove redundant mkdir from ./Kbuild
kbuild: optimize object directory creation for incremental build
kbuild: create object directories simpler and faster
kbuild: filter-out PHONY targets from "targets"
kbuild: remove redundant $(wildcard ...) for cmd_files calculation
kbuild: create directory for make cache only when necessary
sh: select KBUILD_DEFCONFIG depending on ARCH
kbuild: fix linker feature test macros when cross compiling with Clang
kbuild: shrink .cache.mk when it exceeds 1000 lines
kbuild: do not call cc-option before KBUILD_CFLAGS initialization
kbuild: Cache a few more calls to the compiler
kbuild: Add a cache for generated variables
kbuild: add forward declaration of default target to Makefile.asm-generic
kbuild: remove KBUILD_SUBDIR_ASFLAGS and KBUILD_SUBDIR_CCFLAGS
hexagon/kbuild: replace CFLAGS_MODULE with KBUILD_CFLAGS_MODULE
...
97 lines
2.5 KiB
Bash
Executable File
97 lines
2.5 KiB
Bash
Executable File
#!/bin/sh
|
|
# SPDX-License-Identifier: GPL-2.0
|
|
|
|
TARGET=$1
|
|
ARCH=$2
|
|
SMP=$3
|
|
PREEMPT=$4
|
|
CC=$5
|
|
|
|
vecho() { [ "${quiet}" = "silent_" ] || echo "$@" ; }
|
|
|
|
# If compile.h exists already and we don't own autoconf.h
|
|
# (i.e. we're not the same user who did make *config), don't
|
|
# modify compile.h
|
|
# So "sudo make install" won't change the "compiled by <user>"
|
|
# do "compiled by root"
|
|
|
|
if [ -r $TARGET -a ! -O include/generated/autoconf.h ]; then
|
|
vecho " SKIPPED $TARGET"
|
|
exit 0
|
|
fi
|
|
|
|
# Do not expand names
|
|
set -f
|
|
|
|
# Fix the language to get consistent output
|
|
LC_ALL=C
|
|
export LC_ALL
|
|
|
|
if [ -z "$KBUILD_BUILD_VERSION" ]; then
|
|
VERSION=$(cat .version 2>/dev/null || echo 1)
|
|
else
|
|
VERSION=$KBUILD_BUILD_VERSION
|
|
fi
|
|
|
|
if [ -z "$KBUILD_BUILD_TIMESTAMP" ]; then
|
|
TIMESTAMP=`date`
|
|
else
|
|
TIMESTAMP=$KBUILD_BUILD_TIMESTAMP
|
|
fi
|
|
if test -z "$KBUILD_BUILD_USER"; then
|
|
LINUX_COMPILE_BY=$(whoami | sed 's/\\/\\\\/')
|
|
else
|
|
LINUX_COMPILE_BY=$KBUILD_BUILD_USER
|
|
fi
|
|
if test -z "$KBUILD_BUILD_HOST"; then
|
|
LINUX_COMPILE_HOST=`hostname`
|
|
else
|
|
LINUX_COMPILE_HOST=$KBUILD_BUILD_HOST
|
|
fi
|
|
|
|
UTS_VERSION="#$VERSION"
|
|
CONFIG_FLAGS=""
|
|
if [ -n "$SMP" ] ; then CONFIG_FLAGS="SMP"; fi
|
|
if [ -n "$PREEMPT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT"; fi
|
|
UTS_VERSION="$UTS_VERSION $CONFIG_FLAGS $TIMESTAMP"
|
|
|
|
# Truncate to maximum length
|
|
|
|
UTS_LEN=64
|
|
UTS_TRUNCATE="cut -b -$UTS_LEN"
|
|
|
|
# Generate a temporary compile.h
|
|
|
|
( echo /\* This file is auto generated, version $VERSION \*/
|
|
if [ -n "$CONFIG_FLAGS" ] ; then echo "/* $CONFIG_FLAGS */"; fi
|
|
|
|
echo \#define UTS_MACHINE \"$ARCH\"
|
|
|
|
echo \#define UTS_VERSION \"`echo $UTS_VERSION | $UTS_TRUNCATE`\"
|
|
|
|
echo \#define LINUX_COMPILE_BY \"`echo $LINUX_COMPILE_BY | $UTS_TRUNCATE`\"
|
|
echo \#define LINUX_COMPILE_HOST \"`echo $LINUX_COMPILE_HOST | $UTS_TRUNCATE`\"
|
|
|
|
echo \#define LINUX_COMPILER \"`$CC -v 2>&1 | grep ' version ' | sed 's/[[:space:]]*$//'`\"
|
|
) > .tmpcompile
|
|
|
|
# Only replace the real compile.h if the new one is different,
|
|
# in order to preserve the timestamp and avoid unnecessary
|
|
# recompilations.
|
|
# We don't consider the file changed if only the date/time changed.
|
|
# A kernel config change will increase the generation number, thus
|
|
# causing compile.h to be updated (including date/time) due to the
|
|
# changed comment in the
|
|
# first line.
|
|
|
|
if [ -r $TARGET ] && \
|
|
grep -v 'UTS_VERSION' $TARGET > .tmpver.1 && \
|
|
grep -v 'UTS_VERSION' .tmpcompile > .tmpver.2 && \
|
|
cmp -s .tmpver.1 .tmpver.2; then
|
|
rm -f .tmpcompile
|
|
else
|
|
vecho " UPD $TARGET"
|
|
mv -f .tmpcompile $TARGET
|
|
fi
|
|
rm -f .tmpver.1 .tmpver.2
|