90 lines
2.3 KiB
ArmAsm
90 lines
2.3 KiB
ArmAsm
/*
|
|
* Userland implementation of clock_gettime() 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_clock_gettime
|
|
.type __kernel_clock_gettime,@function
|
|
__kernel_clock_gettime:
|
|
.cfi_startproc
|
|
larl %r5,_vdso_data
|
|
cghi %r2,CLOCK_REALTIME
|
|
je 4f
|
|
cghi %r2,CLOCK_MONOTONIC
|
|
jne 9f
|
|
|
|
/* CLOCK_MONOTONIC */
|
|
ltgr %r3,%r3
|
|
jz 3f /* tp == NULL */
|
|
0: 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 */
|
|
mghi %r1,1000
|
|
srlg %r1,%r1,12 /* cyc2ns(clock,cycle_delta) */
|
|
alg %r1,__VDSO_XTIME_NSEC(%r5) /* + xtime */
|
|
lg %r0,__VDSO_XTIME_SEC(%r5)
|
|
alg %r1,__VDSO_WTOM_NSEC(%r5) /* + wall_to_monotonic */
|
|
alg %r0,__VDSO_WTOM_SEC(%r5)
|
|
clg %r4,__VDSO_UPD_COUNT(%r5) /* check update counter */
|
|
jne 0b
|
|
larl %r5,10f
|
|
1: clg %r1,0(%r5)
|
|
jl 2f
|
|
slg %r1,0(%r5)
|
|
aghi %r0,1
|
|
j 1b
|
|
2: stg %r0,0(%r3) /* store tp->tv_sec */
|
|
stg %r1,8(%r3) /* store tp->tv_nsec */
|
|
3: lghi %r2,0
|
|
br %r14
|
|
|
|
/* CLOCK_REALTIME */
|
|
4: ltr %r3,%r3 /* tp == NULL */
|
|
jz 8f
|
|
5: lg %r4,__VDSO_UPD_COUNT(%r5) /* load update counter */
|
|
tmll %r4,0x0001 /* pending update ? loop */
|
|
jnz 5b
|
|
stck 48(%r15) /* Store TOD clock */
|
|
lg %r1,48(%r15)
|
|
sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */
|
|
mghi %r1,1000
|
|
srlg %r1,%r1,12 /* cyc2ns(clock,cycle_delta) */
|
|
alg %r1,__VDSO_XTIME_NSEC(%r5) /* + xtime */
|
|
lg %r0,__VDSO_XTIME_SEC(%r5)
|
|
clg %r4,__VDSO_UPD_COUNT(%r5) /* check update counter */
|
|
jne 5b
|
|
larl %r5,10f
|
|
6: clg %r1,0(%r5)
|
|
jl 7f
|
|
slg %r1,0(%r5)
|
|
aghi %r0,1
|
|
j 6b
|
|
7: stg %r0,0(%r3) /* store tp->tv_sec */
|
|
stg %r1,8(%r3) /* store tp->tv_nsec */
|
|
8: lghi %r2,0
|
|
br %r14
|
|
|
|
/* Fallback to system call */
|
|
9: lghi %r1,__NR_clock_gettime
|
|
svc 0
|
|
br %r14
|
|
|
|
10: .quad 1000000000
|
|
.cfi_endproc
|
|
.size __kernel_clock_gettime,.-__kernel_clock_gettime
|