mirror of
https://github.com/torvalds/linux.git
synced 2024-11-17 17:41:44 +00:00
a30d8a39f0
- Add support for a zstd compressed initramfs. - Add compression for compressing built-in initramfs with zstd. I have tested this patch by boot testing with buildroot and QEMU. Specifically, I booted the kernel with both a zstd and gzip compressed initramfs, both built into the kernel and separate. I ensured that the correct compression algorithm was used. I tested on arm, aarch64, i386, and x86_64. This patch has been tested in production on aarch64 and x86_64 devices. Additionally, I have performance measurements from internal use in production. On an aarch64 device we saw 19 second boot time improvement from switching from lzma to zstd (27 seconds to 8 seconds). On an x86_64 device we saw a 9 second boot time reduction from switching from xz to zstd. Signed-off-by: Nick Terrell <terrelln@fb.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20200730190841.2071656-5-nickrterrell@gmail.com
90 lines
2.9 KiB
Makefile
90 lines
2.9 KiB
Makefile
# SPDX-License-Identifier: GPL-2.0
|
|
#
|
|
# kbuild file for usr/ - including initramfs image
|
|
#
|
|
|
|
# cmd_bzip2, cmd_lzma, cmd_lzo, cmd_lz4 from scripts/Makefile.lib appends the
|
|
# size at the end of the compressed file, which unfortunately does not work
|
|
# with unpack_to_rootfs(). Make size_append no-op.
|
|
override size_append := :
|
|
|
|
compress-y := shipped
|
|
compress-$(CONFIG_INITRAMFS_COMPRESSION_GZIP) := gzip
|
|
compress-$(CONFIG_INITRAMFS_COMPRESSION_BZIP2) := bzip2
|
|
compress-$(CONFIG_INITRAMFS_COMPRESSION_LZMA) := lzma
|
|
compress-$(CONFIG_INITRAMFS_COMPRESSION_XZ) := xzmisc
|
|
compress-$(CONFIG_INITRAMFS_COMPRESSION_LZO) := lzo
|
|
compress-$(CONFIG_INITRAMFS_COMPRESSION_LZ4) := lz4
|
|
compress-$(CONFIG_INITRAMFS_COMPRESSION_ZSTD) := zstd
|
|
|
|
obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o
|
|
|
|
$(obj)/initramfs_data.o: $(obj)/initramfs_inc_data
|
|
|
|
ramfs-input := $(strip $(shell echo $(CONFIG_INITRAMFS_SOURCE)))
|
|
cpio-data :=
|
|
|
|
# If CONFIG_INITRAMFS_SOURCE is empty, generate a small initramfs with the
|
|
# default contents.
|
|
ifeq ($(ramfs-input),)
|
|
ramfs-input := $(srctree)/$(src)/default_cpio_list
|
|
endif
|
|
|
|
ifeq ($(words $(ramfs-input)),1)
|
|
|
|
# If CONFIG_INITRAMFS_SOURCE specifies a single file, and it is suffixed with
|
|
# .cpio, use it directly as an initramfs.
|
|
ifneq ($(filter %.cpio,$(ramfs-input)),)
|
|
cpio-data := $(ramfs-input)
|
|
endif
|
|
|
|
# If CONFIG_INITRAMFS_SOURCE specifies a single file, and it is suffixed with
|
|
# .cpio.*, use it directly as an initramfs, and avoid double compression.
|
|
ifeq ($(words $(subst .cpio.,$(space),$(ramfs-input))),2)
|
|
cpio-data := $(ramfs-input)
|
|
compress-y := shipped
|
|
endif
|
|
|
|
endif
|
|
|
|
# For other cases, generate the initramfs cpio archive based on the contents
|
|
# specified by CONFIG_INITRAMFS_SOURCE.
|
|
ifeq ($(cpio-data),)
|
|
|
|
cpio-data := $(obj)/initramfs_data.cpio
|
|
|
|
hostprogs := gen_init_cpio
|
|
|
|
# .initramfs_data.cpio.d is used to identify all files included
|
|
# in initramfs and to detect if any files are added/removed.
|
|
# Removed files are identified by directory timestamp being updated
|
|
# The dependency list is generated by gen_initramfs.sh -l
|
|
-include $(obj)/.initramfs_data.cpio.d
|
|
|
|
# do not try to update files included in initramfs
|
|
$(deps_initramfs): ;
|
|
|
|
quiet_cmd_initfs = GEN $@
|
|
cmd_initfs = \
|
|
$(CONFIG_SHELL) $< -o $@ -l $(obj)/.initramfs_data.cpio.d \
|
|
$(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \
|
|
$(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID)) \
|
|
$(ramfs-input)
|
|
|
|
# We rebuild initramfs_data.cpio if:
|
|
# 1) Any included file is newer than initramfs_data.cpio
|
|
# 2) There are changes in which files are included (added or deleted)
|
|
# 3) If gen_init_cpio are newer than initramfs_data.cpio
|
|
# 4) Arguments to gen_initramfs.sh changes
|
|
$(obj)/initramfs_data.cpio: $(src)/gen_initramfs.sh $(obj)/gen_init_cpio $(deps_initramfs) FORCE
|
|
$(call if_changed,initfs)
|
|
|
|
endif
|
|
|
|
$(obj)/initramfs_inc_data: $(cpio-data) FORCE
|
|
$(call if_changed,$(compress-y))
|
|
|
|
targets += initramfs_data.cpio initramfs_inc_data
|
|
|
|
subdir-$(CONFIG_UAPI_HEADER_TEST) += include
|