From 9a066357184485784f782719093ff804d05b85db Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 8 Oct 2019 21:05:52 +0900 Subject: kheaders: remove unneeded 'cat' command piped to 'head' / 'tail' The 'head' and 'tail' commands can take a file path directly. So, you do not need to run 'cat'. cat kernel/kheaders.md5 | head -1 ... is equivalent to: head -1 kernel/kheaders.md5 and the latter saves forking one process. While I was here, I replaced 'head -1' with 'head -n 1'. I also replaced '==' with '=' since we do not have a good reason to use the bashism. Signed-off-by: Masahiro Yamada --- kernel/gen_kheaders.sh | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'kernel') diff --git a/kernel/gen_kheaders.sh b/kernel/gen_kheaders.sh index 5a0fc0b0403a..b8054b0d5010 100755 --- a/kernel/gen_kheaders.sh +++ b/kernel/gen_kheaders.sh @@ -41,10 +41,10 @@ obj_files_md5="$(find $dir_list -name "*.h" | this_file_md5="$(ls -l $sfile | md5sum | cut -d ' ' -f1)" if [ -f $tarfile ]; then tarfile_md5="$(md5sum $tarfile | cut -d ' ' -f1)"; fi if [ -f kernel/kheaders.md5 ] && - [ "$(cat kernel/kheaders.md5|head -1)" == "$src_files_md5" ] && - [ "$(cat kernel/kheaders.md5|head -2|tail -1)" == "$obj_files_md5" ] && - [ "$(cat kernel/kheaders.md5|head -3|tail -1)" == "$this_file_md5" ] && - [ "$(cat kernel/kheaders.md5|tail -1)" == "$tarfile_md5" ]; then + [ "$(head -n 1 kernel/kheaders.md5)" = "$src_files_md5" ] && + [ "$(head -n 2 kernel/kheaders.md5 | tail -n 1)" = "$obj_files_md5" ] && + [ "$(head -n 3 kernel/kheaders.md5 | tail -n 1)" = "$this_file_md5" ] && + [ "$(tail -n 1 kernel/kheaders.md5)" = "$tarfile_md5" ]; then exit fi -- cgit From 0e11773e76098729552b750ccff79374d1e62002 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 8 Oct 2019 21:05:53 +0900 Subject: kheaders: optimize md5sum calculation for in-tree builds This script computes md5sum of headers in srctree and in objtree. However, when we are building in-tree, we know the srctree and the objtree are the same. That is, we end up with the same computation twice. In fact, the first two lines of kernel/kheaders.md5 are always the same for in-tree builds. Unify the two md5sum calculations. For in-tree builds ($building_out_of_srctree is empty), we check only two directories, "include", and "arch/$SRCARCH/include". For out-of-tree builds ($building_out_of_srctree is 1), we check 4 directories, "$srctree/include", "$srctree/arch/$SRCARCH/include", "include", and "arch/$SRCARCH/include" since we know they are all different. Signed-off-by: Masahiro Yamada --- kernel/gen_kheaders.sh | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) (limited to 'kernel') diff --git a/kernel/gen_kheaders.sh b/kernel/gen_kheaders.sh index b8054b0d5010..6ff86e62787f 100755 --- a/kernel/gen_kheaders.sh +++ b/kernel/gen_kheaders.sh @@ -21,29 +21,30 @@ arch/$SRCARCH/include/ # Uncomment it for debugging. # if [ ! -f /tmp/iter ]; then iter=1; echo 1 > /tmp/iter; # else iter=$(($(cat /tmp/iter) + 1)); echo $iter > /tmp/iter; fi -# find $src_file_list -name "*.h" | xargs ls -l > /tmp/src-ls-$iter -# find $obj_file_list -name "*.h" | xargs ls -l > /tmp/obj-ls-$iter +# find $all_dirs -name "*.h" | xargs ls -l > /tmp/ls-$iter + +all_dirs= +if [ "$building_out_of_srctree" ]; then + for d in $dir_list; do + all_dirs="$all_dirs $srctree/$d" + done +fi +all_dirs="$all_dirs $dir_list" # include/generated/compile.h is ignored because it is touched even when none # of the source files changed. This causes pointless regeneration, so let us # ignore them for md5 calculation. -pushd $srctree > /dev/null -src_files_md5="$(find $dir_list -name "*.h" | - grep -v "include/generated/compile.h" | - grep -v "include/generated/autoconf.h" | - xargs ls -l | md5sum | cut -d ' ' -f1)" -popd > /dev/null -obj_files_md5="$(find $dir_list -name "*.h" | - grep -v "include/generated/compile.h" | - grep -v "include/generated/autoconf.h" | +headers_md5="$(find $all_dirs -name "*.h" | + grep -v "include/generated/compile.h" | + grep -v "include/generated/autoconf.h" | xargs ls -l | md5sum | cut -d ' ' -f1)" + # Any changes to this script will also cause a rebuild of the archive. this_file_md5="$(ls -l $sfile | md5sum | cut -d ' ' -f1)" if [ -f $tarfile ]; then tarfile_md5="$(md5sum $tarfile | cut -d ' ' -f1)"; fi if [ -f kernel/kheaders.md5 ] && - [ "$(head -n 1 kernel/kheaders.md5)" = "$src_files_md5" ] && - [ "$(head -n 2 kernel/kheaders.md5 | tail -n 1)" = "$obj_files_md5" ] && - [ "$(head -n 3 kernel/kheaders.md5 | tail -n 1)" = "$this_file_md5" ] && + [ "$(head -n 1 kernel/kheaders.md5)" = "$headers_md5" ] && + [ "$(head -n 2 kernel/kheaders.md5 | tail -n 1)" = "$this_file_md5" ] && [ "$(tail -n 1 kernel/kheaders.md5)" = "$tarfile_md5" ]; then exit fi @@ -79,8 +80,7 @@ find $cpio_dir -printf "./%P\n" | LC_ALL=C sort | \ --owner=0 --group=0 --numeric-owner --no-recursion \ -Jcf $tarfile -C $cpio_dir/ -T - > /dev/null -echo "$src_files_md5" > kernel/kheaders.md5 -echo "$obj_files_md5" >> kernel/kheaders.md5 +echo $headers_md5 > kernel/kheaders.md5 echo "$this_file_md5" >> kernel/kheaders.md5 echo "$(md5sum $tarfile | cut -d ' ' -f1)" >> kernel/kheaders.md5 -- cgit From ea79e5168be644fdaf7d4e6a73eceaf07b3da76a Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 8 Oct 2019 21:05:54 +0900 Subject: kheaders: optimize header copy for in-tree builds This script copies headers by the cpio command twice; first from srctree, and then from objtree. However, when we building in-tree, we know the srctree and the objtree are the same. That is, all the headers copied by the first cpio are overwritten by the second one. Skip the first cpio when we are building in-tree. Signed-off-by: Masahiro Yamada --- kernel/gen_kheaders.sh | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'kernel') diff --git a/kernel/gen_kheaders.sh b/kernel/gen_kheaders.sh index 6ff86e62787f..0f7752dd93a6 100755 --- a/kernel/gen_kheaders.sh +++ b/kernel/gen_kheaders.sh @@ -56,14 +56,16 @@ fi rm -rf $cpio_dir mkdir $cpio_dir -pushd $srctree > /dev/null -for f in $dir_list; - do find "$f" -name "*.h"; -done | cpio --quiet -pd $cpio_dir -popd > /dev/null +if [ "$building_out_of_srctree" ]; then + pushd $srctree > /dev/null + for f in $dir_list + do find "$f" -name "*.h"; + done | cpio --quiet -pd $cpio_dir + popd > /dev/null +fi -# The second CPIO can complain if files already exist which can -# happen with out of tree builds. Just silence CPIO for now. +# The second CPIO can complain if files already exist which can happen with out +# of tree builds having stale headers in srctree. Just silence CPIO for now. for f in $dir_list; do find "$f" -name "*.h"; done | cpio --quiet -pd $cpio_dir >/dev/null 2>&1 -- cgit From 1463f74f492eea7191f0178e01f3d38371a48210 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 8 Oct 2019 21:05:55 +0900 Subject: kheaders: remove the last bashism to allow sh to run it 'pushd' ... 'popd' is the last bash-specific code in this script. One way to avoid it is to run the code in a sub-shell. With that addressed, you can run this script with sh. I replaced $(BASH) with $(CONFIG_SHELL), and I changed the hashbang to #!/bin/sh. Signed-off-by: Masahiro Yamada --- kernel/Makefile | 2 +- kernel/gen_kheaders.sh | 13 +++++++------ 2 files changed, 8 insertions(+), 7 deletions(-) (limited to 'kernel') diff --git a/kernel/Makefile b/kernel/Makefile index daad787fb795..42557f251fea 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -128,7 +128,7 @@ $(obj)/config_data.gz: $(KCONFIG_CONFIG) FORCE $(obj)/kheaders.o: $(obj)/kheaders_data.tar.xz quiet_cmd_genikh = CHK $(obj)/kheaders_data.tar.xz - cmd_genikh = $(BASH) $(srctree)/kernel/gen_kheaders.sh $@ + cmd_genikh = $(CONFIG_SHELL) $(srctree)/kernel/gen_kheaders.sh $@ $(obj)/kheaders_data.tar.xz: FORCE $(call cmd,genikh) diff --git a/kernel/gen_kheaders.sh b/kernel/gen_kheaders.sh index 0f7752dd93a6..dc5744b93f8c 100755 --- a/kernel/gen_kheaders.sh +++ b/kernel/gen_kheaders.sh @@ -1,4 +1,4 @@ -#!/bin/bash +#!/bin/sh # SPDX-License-Identifier: GPL-2.0 # This script generates an archive consisting of kernel headers @@ -57,11 +57,12 @@ rm -rf $cpio_dir mkdir $cpio_dir if [ "$building_out_of_srctree" ]; then - pushd $srctree > /dev/null - for f in $dir_list - do find "$f" -name "*.h"; - done | cpio --quiet -pd $cpio_dir - popd > /dev/null + ( + cd $srctree + for f in $dir_list + do find "$f" -name "*.h"; + done | cpio --quiet -pd $cpio_dir + ) fi # The second CPIO can complain if files already exist which can happen with out -- cgit From f276031b4e2f4c961ed6d8a42f0f0124ccac2e09 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 8 Oct 2019 21:05:56 +0900 Subject: kheaders: explain why include/config/autoconf.h is excluded from md5sum This comment block explains why include/generated/compile.h is omitted, but nothing about include/generated/autoconf.h, which might be more difficult to understand. Add more comments. Signed-off-by: Masahiro Yamada --- kernel/gen_kheaders.sh | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/gen_kheaders.sh b/kernel/gen_kheaders.sh index dc5744b93f8c..e13ca842eb7e 100755 --- a/kernel/gen_kheaders.sh +++ b/kernel/gen_kheaders.sh @@ -32,8 +32,15 @@ fi all_dirs="$all_dirs $dir_list" # include/generated/compile.h is ignored because it is touched even when none -# of the source files changed. This causes pointless regeneration, so let us -# ignore them for md5 calculation. +# of the source files changed. +# +# When Kconfig regenerates include/generated/autoconf.h, its timestamp is +# updated, but the contents might be still the same. When any CONFIG option is +# changed, Kconfig touches the corresponding timestamp file include/config/*.h. +# Hence, the md5sum detects the configuration change anyway. We do not need to +# check include/generated/autoconf.h explicitly. +# +# Ignore them for md5 calculation to avoid pointless regeneration. headers_md5="$(find $all_dirs -name "*.h" | grep -v "include/generated/compile.h" | grep -v "include/generated/autoconf.h" | -- cgit