arch/s390/kernel/vdso32/clock_getres.S

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Userland implementation of clock_getres() for 32 bits processes in a
   4  * s390 kernel for use in the vDSO
   5  *
   6  *  Copyright IBM Corp. 2008
   7  *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  */
   9 #include <asm/vdso.h>
  10 #include <asm/asm-offsets.h>
  11 #include <asm/unistd.h>
  12
  13         .text
  14         .align 4
  15         .globl __kernel_clock_getres
  16         .type  __kernel_clock_getres,@function
  17 __kernel_clock_getres:
  18         .cfi_startproc
  19         basr    %r1,0
  20         la      %r1,4f-.(%r1)
  21         chi     %r2,__CLOCK_REALTIME
  22         je      0f
  23         chi     %r2,__CLOCK_MONOTONIC
  24         je      0f
  25         la      %r1,5f-4f(%r1)
  26         chi     %r2,__CLOCK_REALTIME_COARSE
  27         je      0f
  28         chi     %r2,__CLOCK_MONOTONIC_COARSE
  29         jne     3f
  30 0:      ltr     %r3,%r3
  31         jz      2f                              /* res == NULL */
  32 1:      l       %r0,0(%r1)
  33         xc      0(4,%r3),0(%r3)                 /* set tp->tv_sec to zero */
  34         st      %r0,4(%r3)                      /* store tp->tv_usec */
  35 2:      lhi     %r2,0
  36         br      %r14
  37 3:      lhi     %r1,__NR_clock_getres           /* fallback to svc */
  38         svc     0
  39         br      %r14
  40 4:      .long   __CLOCK_REALTIME_RES
  41 5:      .long   __CLOCK_COARSE_RES
  42         .cfi_endproc
  43         .size   __kernel_clock_getres,.-__kernel_clock_getres