While examining vmlinux namelist on i386 (nm -v vmlinux) I noticed :
c01021d0 t es7000_rename_gsi
c010221a T es7000_start_cpu
<Big Hole>
c0103000 T thread_saved_pc
and
c0113218 T acpi_restore_state_mem
c0113219 T acpi_save_state_mem
<Big Hole>
c0114000 t wakeup_code
This is because arch/x86/kernel/acpi/wakeup_32.S forces a .text alignment
of 4096 bytes. (I have no idea if it is really needed, since
arch/x86/kernel/acpi/wakeup_64.S uses a 16 bytes alignment *only*)
So arch/x86/kernel/built-in.o also has this alignment
arch/x86/kernel/built-in.o: file format elf32-i386
Sections:
Idx Name Size VMA LMA File off Algn
0 .text 00018c94 00000000 00000000 00001000 2**12
CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
But as arch/x86/kernel/acpi/wakeup_32.o is not the first object linked
into arch/x86/kernel/built-in.o, linker had to build several holes to meet
alignement requirements, because of .o nestings in the kbuild process.
This can be solved by using a special section, .text.page_aligned, so that
no holes are needed.
# size vmlinux.before vmlinux.after
text data bss dec hex filename
4619942 422838 458752 5501532 53f25c vmlinux.before
4610534 422838 458752 5492124 53cd9c vmlinux.after
This saves 9408 bytes
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
4c4915627f