79c74ecbeb
Switch to the improved update_vsyscall interface that provides sub-nanosecond precision for gettimeofday and clock_gettime. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
58 lines
1.6 KiB
ArmAsm
58 lines
1.6 KiB
ArmAsm
/*
|
|
* Userland implementation of gettimeofday() for 64 bits processes in a
|
|
* s390 kernel for use in the vDSO
|
|
*
|
|
* Copyright IBM Corp. 2008
|
|
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License (version 2 only)
|
|
* as published by the Free Software Foundation.
|
|
*/
|
|
#include <asm/vdso.h>
|
|
#include <asm/asm-offsets.h>
|
|
#include <asm/unistd.h>
|
|
|
|
.text
|
|
.align 4
|
|
.globl __kernel_gettimeofday
|
|
.type __kernel_gettimeofday,@function
|
|
__kernel_gettimeofday:
|
|
.cfi_startproc
|
|
larl %r5,_vdso_data
|
|
0: ltgr %r3,%r3 /* check if tz is NULL */
|
|
je 1f
|
|
mvc 0(8,%r3),__VDSO_TIMEZONE(%r5)
|
|
1: ltgr %r2,%r2 /* check if tv is NULL */
|
|
je 4f
|
|
lg %r4,__VDSO_UPD_COUNT(%r5) /* load update counter */
|
|
tmll %r4,0x0001 /* pending update ? loop */
|
|
jnz 0b
|
|
stck 48(%r15) /* Store TOD clock */
|
|
lg %r1,48(%r15)
|
|
sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */
|
|
msgf %r1,__VDSO_TK_MULT(%r5) /* * tk->mult */
|
|
alg %r1,__VDSO_XTIME_NSEC(%r5) /* + tk->xtime_nsec */
|
|
lg %r0,__VDSO_XTIME_SEC(%r5) /* tk->xtime_sec */
|
|
clg %r4,__VDSO_UPD_COUNT(%r5) /* check update counter */
|
|
jne 0b
|
|
lgf %r5,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */
|
|
srlg %r1,%r1,0(%r5) /* >> tk->shift */
|
|
larl %r5,5f
|
|
2: clg %r1,0(%r5)
|
|
jl 3f
|
|
slg %r1,0(%r5)
|
|
aghi %r0,1
|
|
j 2b
|
|
3: stg %r0,0(%r2) /* store tv->tv_sec */
|
|
slgr %r0,%r0 /* tv_nsec -> tv_usec */
|
|
ml %r0,8(%r5)
|
|
srlg %r0,%r0,6
|
|
stg %r0,8(%r2) /* store tv->tv_usec */
|
|
4: lghi %r2,0
|
|
br %r14
|
|
5: .quad 1000000000
|
|
.long 274877907
|
|
.cfi_endproc
|
|
.size __kernel_gettimeofday,.-__kernel_gettimeofday
|