tile: Convert VDSO timekeeping to the precise mechanism

The code was only halfarsed converted to the new VSDO update mechanism
and still uses the inaccurate base value which lacks the fractional
part of xtime_nsec. Fix it up.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>

diff --git a/arch/tile/kernel/time.c b/arch/tile/kernel/time.c
index 462dcd0c1700221adda93563b5f7904511a9c656..ae70155c2f16f863ab32b6fc9796d9ba86d5fee0 100644 (file)
--- a/arch/tile/kernel/time.c
+++ b/arch/tile/kernel/time.c
@@ -260,7 +260,6 @@ void update_vsyscall_tz(void)
 
 void update_vsyscall(struct timekeeper *tk)
 {
-       struct timespec wall_time = tk_xtime(tk);
        struct timespec *wtm = &tk->wall_to_monotonic;
        struct clocksource *clock = tk->clock;
 
@@ -271,12 +270,12 @@ void update_vsyscall(struct timekeeper *tk)
        ++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->xtime_clock_sec = tk->xtime_sec;
+       vdso_data->xtime_clock_nsec = tk->xtime_nsec;
        vdso_data->wtom_clock_sec = wtm->tv_sec;
        vdso_data->wtom_clock_nsec = wtm->tv_nsec;
-       vdso_data->mult = clock->mult;
-       vdso_data->shift = clock->shift;
+       vdso_data->mult = tk->mult;
+       vdso_data->shift = tk->shift;
        smp_wmb();
        ++vdso_data->tb_update_count;
 }

diff --git a/arch/tile/kernel/vdso/vgettimeofday.c b/arch/tile/kernel/vdso/vgettimeofday.c
index 51ec8e46f5f90667faef2bef6b195a70bd6a1e3b..e933fb9fbf5c3712b81f553560b8b6a0ec720c35 100644 (file)
--- a/arch/tile/kernel/vdso/vgettimeofday.c
+++ b/arch/tile/kernel/vdso/vgettimeofday.c
@@ -83,10 +83,11 @@ int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
                if (count & 1)
                        continue;
 
-               cycles = (get_cycles() - vdso_data->xtime_tod_stamp);
-               ns = (cycles * vdso_data->mult) >> vdso_data->shift;
                sec = vdso_data->xtime_clock_sec;
-               ns += vdso_data->xtime_clock_nsec;
+               cycles = get_cycles() - vdso_data->xtime_tod_stamp;
+               ns = (cycles * vdso_data->mult) + vdso_data->xtime_clock_nsec;
+               ns >>= vdso_data->shift;
+
                if (ns >= NSEC_PER_SEC) {
                        ns -= NSEC_PER_SEC;
                        sec += 1;