[gentoo-commits] proj/genkernel:ryao commit in: /

[Richard Yao]

commit:     713b523abf4196ef97963cde973cccdce8609d46
Author:     Richard Yao <ryao <AT> gentoo <DOT> org>
AuthorDate: Thu Jun  6 03:14:18 2013 +0000
Commit:     Richard Yao <ryao <AT> gentoo <DOT> org>
CommitDate: Thu Jun  6 03:51:02 2013 +0000
URL:        http://git.overlays.gentoo.org/gitweb/?p=proj/genkernel.git;a=commit;h=713b523a

Remove duplicate files from initramfs

genkernel's initramfs image is built incrementally by appending to the
cpio file. The introduction of copy_binaries resulted in copying
libraries from the host system, which causes the cpio to include certain
libraries multiple times whenever different stages depended upon the
same library. We address this by extracting the cpio to a temporary
directory and then compressing it again to "finalize" it. The extraction
eliminates the duplicate files.

This makes generated initramfs images smaller by approximately 240KB
(post compression) on my system. In theory, this should make the
initramfs load slightly faster.

Signed-off-by: Richard Yao <ryao <AT> gentoo.org>

---
 gen_initramfs.sh | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/gen_initramfs.sh b/gen_initramfs.sh
index 745e15a..6ad51c1 100755
--- a/gen_initramfs.sh
+++ b/gen_initramfs.sh
@@ -796,6 +796,20 @@ create_initramfs() {
 		append_data 'overlay'
 	fi
 
+	# Finalize cpio by removing duplicate files
+	print_info 1 "        >> Finalizing cpio"
+	local TDIR="${TEMP}/initramfs-final"
+	mkdir -p "${TDIR}"
+	cd "${TDIR}"
+
+	cpio --quiet -i -F "${CPIO}" 2> /dev/null \
+		|| gen_die "extracting cpio for finalization"
+	find . -print | cpio ${CPIO_ARGS} -F "${CPIO}" 2>/dev/null \
+		|| gen_die "recompressing cpio"
+
+	cd "${TEMP}"
+	rm -r "${TDIR}"
+
 	if isTrue "${INTEGRATED_INITRAMFS}"
 	then
 		# Explicitly do not compress if we are integrating into the kernel.