kheaders: include only headers into kheaders_data.tar.xz

Currently, kheaders_data.tar.xz contains some build scripts as well as
headers. None of them is needed in the header archive.

For ARCH=x86, this commit excludes the following from the archive:

  arch/x86/include/asm/Kbuild
  arch/x86/include/uapi/asm/Kbuild
  include/asm-generic/Kbuild
  include/config/auto.conf
  include/config/kernel.release
  include/config/tristate.conf
  include/uapi/asm-generic/Kbuild
  include/uapi/Kbuild
  kernel/gen_kheaders.sh

This change is actually motivated for the planned header compile-testing
because it will generate more build artifacts, which should not be
included in the archive.

Change-Id: I9df4bd8ab4b771051ad063035bd7b48b280b018f
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Git-commit: 199ff7d74003b5aad1e6328bf6128cd8ceea735  
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Gaurav Kohli <gkohli@codeaurora.org>

kernel/gen_kheaders.sh

@@ -4,24 +4,12 @@
 # This script generates an archive consisting of kernel headers
 # for CONFIG_IKHEADERS.
 set -e
-spath="$(dirname "$(readlink -f "$0")")"
-kroot="$spath/.."
+sfile="$(readlink -f "$0")"
 outdir="$(pwd)"
 tarfile=$1
 cpio_dir=$outdir/$tarfile.tmp
 
-# Script filename relative to the kernel source root
-# We add it to the archive because it is small and any changes
-# to this script will also cause a rebuild of the archive.
-sfile="$(realpath --relative-to $kroot "$(readlink -f "$0")")"
-
-src_file_list="
-include/
-arch/$SRCARCH/include/
-$sfile
-"
-
-obj_file_list="
+dir_list="
 include/
 arch/$SRCARCH/include/
 "
@@ -33,33 +21,29 @@ 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 $src_file_list -type f | xargs ls -l > /tmp/src-ls-$iter
-# find $obj_file_list -type f | xargs ls -l > /tmp/obj-ls-$iter
+# 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
 
 # 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 $kroot > /dev/null
-src_files_md5="$(find $src_file_list -type f                       |
+pushd $srctree > /dev/null
+src_files_md5="$(find $dir_list -name "*.h"			   |
 		grep -v "include/generated/compile.h"		   |
 		grep -v "include/generated/autoconf.h"		   |
-		grep -v "include/config/auto.conf"		   |
-		grep -v "include/config/auto.conf.cmd"		   |
-		grep -v "include/config/tristate.conf"		   |
 		xargs ls -l | md5sum | cut -d ' ' -f1)"
 popd > /dev/null
-obj_files_md5="$(find $obj_file_list -type f                       |
+obj_files_md5="$(find $dir_list -name "*.h"			   |
 		grep -v "include/generated/compile.h"		   |
 		grep -v "include/generated/autoconf.h"		   |
-		grep -v "include/config/auto.conf"                 |
-		grep -v "include/config/auto.conf.cmd"		   |
-		grep -v "include/config/tristate.conf"		   |
 		xargs ls -l | md5sum | cut -d ' ' -f1)"
-
+# Any changes to this script will also cause a rebuild of the archive.
+this_file_md5="$(ls -l $sfile | md5sum | cut -d ' ' -f1)"
 if [ -f $tarfile ]; then tarfile_md5="$(md5sum $tarfile | cut -d ' ' -f1)"; fi
 if [ -f kernel/kheaders.md5 ] &&
 	[ "$(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
 		exit
 fi
@@ -71,16 +55,16 @@ fi
 rm -rf $cpio_dir
 mkdir $cpio_dir
 
-pushd $kroot > /dev/null
-for f in $src_file_list;
-	do find "$f" ! -name "*.cmd" ! -name ".*";
+pushd $srctree > /dev/null
+for f in $dir_list;
+	do find "$f" -name "*.h";
 done | cpio --quiet -pd $cpio_dir
 popd > /dev/null
 
 # The second CPIO can complain if files already exist which can
 # happen with out of tree builds. Just silence CPIO for now.
-for f in $obj_file_list;
-	do find "$f" ! -name "*.cmd" ! -name ".*";
+for f in $dir_list;
+	do find "$f" -name "*.h";
 done | cpio --quiet -pd $cpio_dir >/dev/null 2>&1
 
 # Remove comments except SDPX lines
@@ -91,6 +75,7 @@ tar -Jcf $tarfile -C $cpio_dir/ . > /dev/null
 
 echo "$src_files_md5" >  kernel/kheaders.md5
 echo "$obj_files_md5" >> kernel/kheaders.md5
+echo "$this_file_md5" >> kernel/kheaders.md5
 echo "$(md5sum $tarfile | cut -d ' ' -f1)" >> kernel/kheaders.md5
 
 rm -rf $cpio_dir