vdso.c
/*
* Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
* Copyright 2003 Andi Kleen, SuSE Labs.
*
* Thanks to hpa@transmeta.com for some useful hint.
* Special thanks to Ingo Molnar for his early experience with
* a different vsyscall implementation for Linux/IA32 and for the name.
*/
#include <linux/time.h>
#include <linux/timekeeper_internal.h>
#include <asm/vvar.h>
void update_vsyscall_tz(void)
{
if (unlikely(vvar_data == NULL))
return;
vvar_data->tz_minuteswest = sys_tz.tz_minuteswest;
vvar_data->tz_dsttime = sys_tz.tz_dsttime;
}
void update_vsyscall(struct timekeeper *tk)
{
struct vvar_data *vdata = vvar_data;
if (unlikely(vdata == NULL))
return;
vvar_write_begin(vdata);
vdata->vclock_mode = tk->tkr_mono.clock->archdata.vclock_mode;
vdata->clock.cycle_last = tk->tkr_mono.cycle_last;
vdata->clock.mask = tk->tkr_mono.mask;
vdata->clock.mult = tk->tkr_mono.mult;
vdata->clock.shift = tk->tkr_mono.shift;
vdata->wall_time_sec = tk->xtime_sec;
vdata->wall_time_snsec = tk->tkr_mono.xtime_nsec;
vdata->monotonic_time_sec = tk->xtime_sec +
tk->wall_to_monotonic.tv_sec;
vdata->monotonic_time_snsec = tk->tkr_mono.xtime_nsec +
(tk->wall_to_monotonic.tv_nsec <<
tk->tkr_mono.shift);
while (vdata->monotonic_time_snsec >=
(((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) {
vdata->monotonic_time_snsec -=
((u64)NSEC_PER_SEC) << tk->tkr_mono.shift;
vdata->monotonic_time_sec++;
}
vdata->wall_time_coarse_sec = tk->xtime_sec;
vdata->wall_time_coarse_nsec =
(long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
vdata->monotonic_time_coarse_sec =
vdata->wall_time_coarse_sec + tk->wall_to_monotonic.tv_sec;
vdata->monotonic_time_coarse_nsec =
vdata->wall_time_coarse_nsec + tk->wall_to_monotonic.tv_nsec;
while (vdata->monotonic_time_coarse_nsec >= NSEC_PER_SEC) {
vdata->monotonic_time_coarse_nsec -= NSEC_PER_SEC;
vdata->monotonic_time_coarse_sec++;
}
vvar_write_end(vdata);
}