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b020632e40
Add a vdso to speed up gettimeofday and clock_getres/clock_gettime for CLOCK_REALTIME/CLOCK_MONOTONIC. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
40 lines
1020 B
ArmAsm
40 lines
1020 B
ArmAsm
/*
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* Userland implementation of clock_getres() for 32 bits processes in a
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* s390 kernel for use in the vDSO
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*
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* Copyright IBM Corp. 2008
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* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License (version 2 only)
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* as published by the Free Software Foundation.
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*/
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#include <asm/vdso.h>
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#include <asm/asm-offsets.h>
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#include <asm/unistd.h>
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.text
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.align 4
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.globl __kernel_clock_getres
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.type __kernel_clock_getres,@function
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__kernel_clock_getres:
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.cfi_startproc
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chi %r2,CLOCK_REALTIME
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je 0f
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chi %r2,CLOCK_MONOTONIC
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jne 3f
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0: ltr %r3,%r3
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jz 2f /* res == NULL */
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basr %r1,0
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1: l %r0,4f-1b(%r1)
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xc 0(4,%r3),0(%r3) /* set tp->tv_sec to zero */
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st %r0,4(%r3) /* store tp->tv_usec */
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2: lhi %r2,0
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br %r14
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3: lhi %r1,__NR_clock_getres /* fallback to svc */
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svc 0
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br %r14
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4: .long CLOCK_REALTIME_RES
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.cfi_endproc
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.size __kernel_clock_getres,.-__kernel_clock_getres
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