kernel_optimize_test/arch/x86/vdso/vdso.lds.S
Roland McGrath c65916fe35 x86: vdso linker script cleanup
I can't see the reason ".  = VDSO_PRELINK + 0x900;" was ever there in
the linker script for the x86_64 vDSO.  I can't find anything that
depends on this magic offset, or that should care at all about the
particular location of of the .data section (all from vvar.c) in the
vDSO image.  If it is really desireable to place .data at 0x900, then it
should be after all the other sections so they fill in the space up to
0x900.

This removes the 0x900 magic and cleans up the output sections generally
in the vDSO linker script.  This saves a few hundred bytes in the size
of the vDSO file, bringing it back well under 4kb total so that its vma
only needs one page.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-17 20:17:06 +02:00

80 lines
2.1 KiB
ArmAsm

/*
* Linker script for vsyscall DSO. The vsyscall page is an ELF shared
* object prelinked to its virtual address, and with only one read-only
* segment (that fits in one page). This script controls its layout.
*/
#include <asm/asm-offsets.h>
#include "voffset.h"
#define VDSO_PRELINK 0xffffffffff700000
SECTIONS
{
. = VDSO_PRELINK + SIZEOF_HEADERS;
.hash : { *(.hash) } :text
.gnu.hash : { *(.gnu.hash) }
.dynsym : { *(.dynsym) }
.dynstr : { *(.dynstr) }
.gnu.version : { *(.gnu.version) }
.gnu.version_d : { *(.gnu.version_d) }
.gnu.version_r : { *(.gnu.version_r) }
/* This linker script is used both with -r and with -shared.
For the layouts to match, we need to skip more than enough
space for the dynamic symbol table et al. If this amount
is insufficient, ld -shared will barf. Just increase it here. */
. = VDSO_PRELINK + VDSO_TEXT_OFFSET;
.text : { *(.text*) } :text
.rodata : { *(.rodata*) } :text
.data : {
*(.data*)
*(.sdata*)
*(.bss*)
*(.dynbss*)
} :text
.altinstructions : { *(.altinstructions) } :text
.altinstr_replacement : { *(.altinstr_replacement) } :text
.note : { *(.note.*) } :text :note
.eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr
.eh_frame : { KEEP (*(.eh_frame)) } :text
.dynamic : { *(.dynamic) } :text :dynamic
.useless : {
*(.got.plt) *(.got)
*(.gnu.linkonce.d.*)
*(.gnu.linkonce.b.*)
} :text
}
/*
* We must supply the ELF program headers explicitly to get just one
* PT_LOAD segment, and set the flags explicitly to make segments read-only.
*/
PHDRS
{
text PT_LOAD FILEHDR PHDRS FLAGS(5); /* PF_R|PF_X */
dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
note PT_NOTE FLAGS(4); /* PF_R */
eh_frame_hdr 0x6474e550; /* PT_GNU_EH_FRAME, but ld doesn't match the name */
}
/*
* This controls what symbols we export from the DSO.
*/
VERSION
{
LINUX_2.6 {
global:
clock_gettime;
__vdso_clock_gettime;
gettimeofday;
__vdso_gettimeofday;
getcpu;
__vdso_getcpu;
local: *;
};
}