1/* 2 * Userland implementation of clock_getres() for 64 bits processes in a 3 * s390 kernel for use in the vDSO 4 * 5 * Copyright IBM Corp. 2008 6 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License (version 2 only) 10 * as published by the Free Software Foundation. 11 */ 12#include <asm/vdso.h> 13#include <asm/asm-offsets.h> 14#include <asm/unistd.h> 15 16 .text 17 .align 4 18 .globl __kernel_clock_getres 19 .type __kernel_clock_getres,@function 20__kernel_clock_getres: 21 .cfi_startproc 22 cghi %r2,CLOCK_REALTIME 23 je 0f 24 cghi %r2,CLOCK_MONOTONIC 25 je 0f 26 cghi %r2,-2 /* CLOCK_THREAD_CPUTIME_ID for this thread */ 27 jne 2f 28 larl %r5,_vdso_data 29 icm %r0,15,__LC_ECTG_OK(%r5) 30 jz 2f 310: ltgr %r3,%r3 32 jz 1f /* res == NULL */ 33 larl %r1,3f 34 lg %r0,0(%r1) 35 xc 0(8,%r3),0(%r3) /* set tp->tv_sec to zero */ 36 stg %r0,8(%r3) /* store tp->tv_usec */ 371: lghi %r2,0 38 br %r14 392: lghi %r1,__NR_clock_getres /* fallback to svc */ 40 svc 0 41 br %r14 423: .quad CLOCK_REALTIME_RES 43 .cfi_endproc 44 .size __kernel_clock_getres,.-__kernel_clock_getres 45