vdso.c 1.9 KB

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  1. /*
  2. * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
  3. * Copyright 2003 Andi Kleen, SuSE Labs.
  4. *
  5. * Thanks to hpa@transmeta.com for some useful hint.
  6. * Special thanks to Ingo Molnar for his early experience with
  7. * a different vsyscall implementation for Linux/IA32 and for the name.
  8. */
  9. #include <linux/time.h>
  10. #include <linux/timekeeper_internal.h>
  11. #include <asm/vvar.h>
  12. void update_vsyscall_tz(void)
  13. {
  14. if (unlikely(vvar_data == NULL))
  15. return;
  16. vvar_data->tz_minuteswest = sys_tz.tz_minuteswest;
  17. vvar_data->tz_dsttime = sys_tz.tz_dsttime;
  18. }
  19. void update_vsyscall(struct timekeeper *tk)
  20. {
  21. struct vvar_data *vdata = vvar_data;
  22. if (unlikely(vdata == NULL))
  23. return;
  24. vvar_write_begin(vdata);
  25. vdata->vclock_mode = tk->tkr_mono.clock->archdata.vclock_mode;
  26. vdata->clock.cycle_last = tk->tkr_mono.cycle_last;
  27. vdata->clock.mask = tk->tkr_mono.mask;
  28. vdata->clock.mult = tk->tkr_mono.mult;
  29. vdata->clock.shift = tk->tkr_mono.shift;
  30. vdata->wall_time_sec = tk->xtime_sec;
  31. vdata->wall_time_snsec = tk->tkr_mono.xtime_nsec;
  32. vdata->monotonic_time_sec = tk->xtime_sec +
  33. tk->wall_to_monotonic.tv_sec;
  34. vdata->monotonic_time_snsec = tk->tkr_mono.xtime_nsec +
  35. (tk->wall_to_monotonic.tv_nsec <<
  36. tk->tkr_mono.shift);
  37. while (vdata->monotonic_time_snsec >=
  38. (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) {
  39. vdata->monotonic_time_snsec -=
  40. ((u64)NSEC_PER_SEC) << tk->tkr_mono.shift;
  41. vdata->monotonic_time_sec++;
  42. }
  43. vdata->wall_time_coarse_sec = tk->xtime_sec;
  44. vdata->wall_time_coarse_nsec =
  45. (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
  46. vdata->monotonic_time_coarse_sec =
  47. vdata->wall_time_coarse_sec + tk->wall_to_monotonic.tv_sec;
  48. vdata->monotonic_time_coarse_nsec =
  49. vdata->wall_time_coarse_nsec + tk->wall_to_monotonic.tv_nsec;
  50. while (vdata->monotonic_time_coarse_nsec >= NSEC_PER_SEC) {
  51. vdata->monotonic_time_coarse_nsec -= NSEC_PER_SEC;
  52. vdata->monotonic_time_coarse_sec++;
  53. }
  54. vvar_write_end(vdata);
  55. }