From 7dd65feb6c603e13eba501c34c662259ab38e70e Mon Sep 17 00:00:00 2001 From: Albin Tonnerre Date: Fri, 8 Jan 2010 14:42:42 -0800 Subject: lib: add support for LZO-compressed kernels This patch series adds generic support for creating and extracting LZO-compressed kernel images, as well as support for using such images on the x86 and ARM architectures, and support for creating and using LZO-compressed initrd and initramfs images. Russell King said: : Testing on a Cortex A9 model: : - lzo decompressor is 65% of the time gzip takes to decompress a kernel : - lzo kernel is 9% larger than a gzip kernel : : which I'm happy to say confirms your figures when comparing the two. : : However, when comparing your new gzip code to the old gzip code: : - new is 99% of the size of the old code : - new takes 42% of the time to decompress than the old code : : What this means is that for a proper comparison, the results get even better: : - lzo is 7.5% larger than the old gzip'd kernel image : - lzo takes 28% of the time that the old gzip code took : : So the expense seems definitely worth the effort. The only reason I : can think of ever using gzip would be if you needed the additional : compression (eg, because you have limited flash to store the image.) : : I would argue that the default for ARM should therefore be LZO. This patch: The lzo compressor is worse than gzip at compression, but faster at extraction. Here are some figures for an ARM board I'm working on: Uncompressed size: 3.24Mo gzip 1.61Mo 0.72s lzo 1.75Mo 0.48s So for a compression ratio that is still relatively close to gzip, it's much faster to extract, at least in that case. This part contains: - Makefile routine to support lzo compression - Fixes to the existing lzo compressor so that it can be used in compressed kernels - wrapper around the existing lzo1x_decompress, as it only extracts one block at a time, while we need to extract a whole file here - config dialog for kernel compression [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: cleanup] Signed-off-by: Albin Tonnerre Tested-by: Wu Zhangjin Acked-by: "H. Peter Anvin" Cc: Ingo Molnar Cc: Thomas Gleixner Tested-by: Russell King Acked-by: Russell King Cc: Ralf Baechle Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/Makefile.lib | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'scripts/Makefile.lib') diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index cd815ac2a50b..0fe48cd91ffa 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -235,3 +235,8 @@ quiet_cmd_lzma = LZMA $@ cmd_lzma = (cat $(filter-out FORCE,$^) | \ lzma -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ (rm -f $@ ; false) + +quiet_cmd_lzo = LZO $@ +cmd_lzo = (cat $(filter-out FORCE,$^) | \ + lzop -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ + (rm -f $@ ; false) -- cgit v1.2.3 From 1373411ae4cd0caf2e1a35fb801dd9a00b64dea2 Mon Sep 17 00:00:00 2001 From: Jonathan Nieder Date: Mon, 28 Dec 2009 19:38:27 +0000 Subject: kbuild: really fix bzImage build with non-bash sh MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In an x86 build with CONFIG_KERNEL_LZMA enabled and dash as sh, arch/x86/boot/compressed/vmlinux.bin.lzma ends with '\xf0\x7d\x39\x00' (16 bytes) instead of the 4 bytes intended and the resulting vmlinuz fails to boot. This improves on the previous behavior, in which the file contained the characters '-ne ' as well, but not by much. Previous commits replaced "echo -ne" first with "/bin/echo -ne", then "printf" in the hope of improving portability, but none of these commands is guaranteed to support hexadecimal escapes on POSIX systems. So use the shell to convert from hexadecimal to octal. With this change, an LZMA-compressed kernel built with dash as sh boots correctly again. Reported-by: Sebastian Dalfuß Reported-by: Oliver Hartkopp Reported-by: Michael Guntsche Signed-off-by: Jonathan Nieder Cc: Michael Tokarev Cc: Alek Du Cc: Andrew Morton Signed-off-by: Michal Marek --- scripts/Makefile.lib | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'scripts/Makefile.lib') diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 0fe48cd91ffa..f9bdf264473d 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -219,8 +219,13 @@ for F in $1; do \ fsize=$$(stat -c "%s" $$F); \ dec_size=$$(expr $$dec_size + $$fsize); \ done; \ -printf "%08x" $$dec_size | \ - sed 's/\(..\)\(..\)\(..\)\(..\)/\\\\x\4\\\\x\3\\\\x\2\\\\x\1/g' \ +printf "%08x\n" $$dec_size | \ + sed 's/\(..\)/\1 /g' | { \ + read ch0 ch1 ch2 ch3; \ + for ch in $$ch3 $$ch2 $$ch1 $$ch0; do \ + printf '%s%03o' '\\' $$((0x$$ch)); \ + done; \ + } \ ) quiet_cmd_bzip2 = BZIP2 $@ -- cgit v1.2.3