Commit 2bb79470 authored by Thomas Weißschuh's avatar Thomas Weißschuh Committed by Thomas Gleixner
Browse files

ARM: vdso: Remove assembly for datapage access 



vdso/datapage.h provides a hidden declaration for _vdso_data.
When using it the compiler will automatically generate PC-relative
accesses which avoids the need for a custom assembly-based accessor.

Signed-off-by: default avatarThomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20241010-vdso-generic-base-v1-7-b64f0842d512@linutronix.de
parent d34b6075

arch/arm/include/asm/vdso/gettimeofday.h

+1 −3
Original line number Diff line number Diff line
@@ -15,8 +15,6 @@ 


#define VDSO_HAS_CLOCK_GETRES		1



extern struct vdso_data *__get_datapage(void);



static __always_inline int gettimeofday_fallback(

				struct __kernel_old_timeval *_tv,

				struct timezone *_tz)
@@ -139,7 +137,7 @@ static __always_inline u64 __arch_get_hw_counter(int clock_mode, 


static __always_inline const struct vdso_data *__arch_get_vdso_data(void)

{

	return __get_datapage();

	return _vdso_data;

}



#endif /* !__ASSEMBLY__ */

arch/arm/vdso/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -5,7 +5,7 @@ include $(srctree)/lib/vdso/Makefile 


hostprogs := vdsomunge



obj-vdso := vgettimeofday.o datapage.o note.o

obj-vdso := vgettimeofday.o note.o



# Build rules

targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.so.raw vdso.lds

arch/arm/vdso/datapage.S

deleted100644 → 0
+0 −16
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#include <linux/linkage.h>

#include <asm/asm-offsets.h>



	.align 2

.L_vdso_data_ptr:

	.long	_start - . - VDSO_DATA_SIZE



ENTRY(__get_datapage)

	.fnstart

	adr	r0, .L_vdso_data_ptr

	ldr	r1, [r0]

	add	r0, r0, r1

	bx	lr

	.fnend

ENDPROC(__get_datapage)

arch/arm/vdso/vdso.lds.S

+2 −1
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 
 */



#include <linux/const.h>

#include <asm/asm-offsets.h>

#include <asm/page.h>

#include <asm/vdso.h>
@@ -19,7 +20,7 @@ OUTPUT_ARCH(arm) 


SECTIONS

{

	PROVIDE(_start = .);

	PROVIDE(_vdso_data = . - VDSO_DATA_SIZE);



	. = SIZEOF_HEADERS;