On Wed, 2016-01-20 at 10:05 +0100, Ard Biesheuvel wrote: > This enables the newly introduced text-relative kallsyms support when > building 64-bit targets. This cuts the size of the kallsyms address > table in half, and drastically reduces the size of the PIE dynamic > relocation section when building with CONFIG_RELOCATABLE=y (by about > 3 MB for ppc64_defconfig) > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> > --- > > Results for ppc64_defconfig: > > BEFORE: > ======= > $ size vmlinux > text data bss dec hex filename > 19827996 2008456 849612 22686064 15a2970 vmlinux > > $ readelf -S .tmp_kallsyms2.o > There are 9 section headers, starting at offset 0x4513f8: > > Section Headers: > [Nr] Name Type Address Offset > Size EntSize Flags Link Info Align > ... > [ 4] .rodata PROGBITS 0000000000000000 00000100 > 00000000001fcf00 0000000000000000 A 0 0 256 > [ 5] .rela.rodata RELA 0000000000000000 001fd1d8 > 0000000000254220 0000000000000018 I 7 4 8 > [ 6] .shstrtab STRTAB 0000000000000000 001fd000 > 0000000000000039 0000000000000000 0 0 1 > ... > > $ ls -l arch/powerpc/boot/zImage > -rwxrwxr-x 2 ard ard 7533160 Jan 20 08:43 arch/powerpc/boot/zImage > > AFTER: > ====== > $ size vmlinux > text data bss dec hex filename > 16979516 2009992 849612 19839120 12eb890 vmlinux > > $ readelf -S .tmp_kallsyms2.o > There are 8 section headers, starting at offset 0x199bb0: > > Section Headers: > [Nr] Name Type Address Offset > Size EntSize Flags Link Info Align > ... > [ 4] .rodata PROGBITS 0000000000000000 00000100 > 0000000000199900 0000000000000000 A 0 0 256 > [ 5] .shstrtab STRTAB 0000000000000000 00199a00 > 0000000000000034 0000000000000000 0 0 1 > ... > > $ ls -l arch/powerpc/boot/zImage > -rwxrwxr-x 2 ard ard 6985672 Jan 20 08:45 arch/powerpc/boot/zImage Nice space saving, thanks very much. I've booted this on a bunch of machines and it seems to be working fine. Tested-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> (powerpc) cheers -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
