On Tue, Apr 17, 2018 at 12:49 PM, Christophe Leroy <christophe.le...@c-s.fr> wrote: > This option does dead code and data elimination with the linker by > compiling with -ffunction-sections -fdata-sections and linking with > --gc-sections. > > By selecting this option on mpc885_ads_defconfig, > vmlinux LOAD segment size gets reduced by 10% > > Program Header before the patch: > LOAD off 0x00010000 vaddr 0xc0000000 paddr 0x00000000 align 2**16 > filesz 0x0036eda4 memsz 0x0038de04 flags rwx > > Program Header after the patch: > LOAD off 0x00010000 vaddr 0xc0000000 paddr 0x00000000 align 2**16 > filesz 0x00316da4 memsz 0x00334268 flags rwx > > Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr> > --- > arch/powerpc/Kconfig | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > index 8fe4353be5e3..e1fac49cf465 100644 > --- a/arch/powerpc/Kconfig > +++ b/arch/powerpc/Kconfig > @@ -888,6 +888,14 @@ config PPC_MEM_KEYS > > If unsure, say y. > > +config PPC_UNUSED_ELIMINATION > + bool "Eliminate unused functions and data from vmlinux" > + default n > + select LD_DEAD_CODE_DATA_ELIMINATION > + help > + Select this to do dead code and data elimination with the linker > + by compiling with -ffunction-sections -fdata-sections and linking > + with --gc-sections. > endmenu >
Just for reference, I cannot boot my Mac Mini G4 anymore (yaboot). The messages I can see (prom_init) are: --- done copying OF device tree... Building dt strings... Building dt structure... Device tree strings 0x01100000 -> 0x01100e02 Device tree struct 0x01101000 -> 0x01109000 Quiescing Open Firmware ... Booting Linux via __start() @ 0x00140000 ... _ --- > config ISA_DMA_API > -- > 2.13.3 >
