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s390/time,vdso: convert to the new update_vsyscall interface

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Switch to the improved update_vsyscall interface that provides
sub-nanosecond precision for gettimeofday and clock_gettime.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Martin Schwidefsky
2013-11-22 10:04:53 +01:00
parent 71a86ef055
commit 79c74ecbeb
8 changed files with 62 additions and 45 deletions
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27
arch/s390/kernel/time.c
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@@ -221,21 +221,30 @@ struct clocksource * __init clocksource_default_clock(void)
return &clocksource_tod;
}
void update_vsyscall_old(struct timespec *wall_time, struct timespec *wtm,
struct clocksource *clock, u32 mult)
void update_vsyscall(struct timekeeper *tk)
{
if (clock != &clocksource_tod)
u64 nsecps;
if (tk->clock != &clocksource_tod)
return;
/* Make userspace gettimeofday spin until we're done. */
++vdso_data->tb_update_count;
smp_wmb();
vdso_data->xtime_tod_stamp = clock->cycle_last;
vdso_data->xtime_clock_sec = wall_time->tv_sec;
vdso_data->xtime_clock_nsec = wall_time->tv_nsec;
vdso_data->wtom_clock_sec = wtm->tv_sec;
vdso_data->wtom_clock_nsec = wtm->tv_nsec;
vdso_data->ntp_mult = mult;
vdso_data->xtime_tod_stamp = tk->clock->cycle_last;
vdso_data->xtime_clock_sec = tk->xtime_sec;
vdso_data->xtime_clock_nsec = tk->xtime_nsec;
vdso_data->wtom_clock_sec =
tk->xtime_sec + tk->wall_to_monotonic.tv_sec;
vdso_data->wtom_clock_nsec = tk->xtime_nsec +
+ (tk->wall_to_monotonic.tv_nsec << tk->shift);
nsecps = (u64) NSEC_PER_SEC << tk->shift;
while (vdso_data->wtom_clock_nsec >= nsecps) {
vdso_data->wtom_clock_nsec -= nsecps;
vdso_data->wtom_clock_sec++;
}
vdso_data->tk_mult = tk->mult;
vdso_data->tk_shift = tk->shift;
smp_wmb();
++vdso_data->tb_update_count;
}