linux/init
Nicholas Piggin b67067f117 kbuild: allow archs to select link dead code/data elimination
Introduce LD_DEAD_CODE_DATA_ELIMINATION option for architectures to
select to build with -ffunction-sections, -fdata-sections, and link
with --gc-sections. It requires some work (documented) to ensure all
unreferenced entrypoints are live, and requires toolchain and build
verification, so it is made a per-arch option for now.

On a random powerpc64le build, this yelds a significant size saving,
it boots and runs fine, but there is a lot I haven't tested as yet, so
these savings may be reduced if there are bugs in the link.

    text      data        bss        dec   filename
11169741   1180744    1923176	14273661   vmlinux
10445269   1004127    1919707	13369103   vmlinux.dce

~700K text, ~170K data, 6% removed from kernel image size.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-09-09 10:47:00 +02:00
..
calibrate.c kernel: add calibration_delay_done() 2014-06-16 12:47:39 -06:00
do_mounts.c init/do_mounts.c: add create_dev() failure log 2015-06-25 17:00:42 -07:00
do_mounts.h init/do_mounts: initrd_load() can be boolean 2016-01-20 17:09:18 -08:00
do_mounts_initrd.c init/do_mounts: initrd_load() can be boolean 2016-01-20 17:09:18 -08:00
do_mounts_md.c init: disable sparse checking of the mount.o source files 2012-05-31 17:49:27 -07:00
do_mounts_rd.c init, Documentation: Remove ramdisk_blocksize mentions 2015-12-26 05:22:00 -07:00
init_task.c sched/rt: Move rt specific bits into new header file 2013-02-07 20:51:08 +01:00
initramfs.c kexec: split kexec_load syscall from kexec core code 2015-09-10 13:29:01 -07:00
Kconfig init/Kconfig: add clarification for out-of-tree modules 2016-08-02 19:35:43 -04:00
main.c init: allow blacklisting of module_init functions 2016-08-02 19:35:40 -04:00
Makefile kbuild: allow archs to select link dead code/data elimination 2016-09-09 10:47:00 +02:00
noinitramfs.c init: mark __user address space on string literals 2010-10-26 16:52:15 -07:00
version.c copy address of proc_ns_ops into ns_common 2014-12-04 14:34:47 -05:00