From: Thomas Gleixner <tglx@linutronix.de>
Date: Wed, 16 Jul 2014 21:03:49 +0000 (+0000)
Subject: tile: Convert VDSO timekeeping to the precise mechanism
X-Git-Tag: MMI-PSA29.97-13-9~11784^2~68
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=dc01c9fae1c5e40458c086a868d2028dfd6faebd;p=GitHub%2FMotorolaMobilityLLC%2Fkernel-slsi.git

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 462dcd0c1700..ae70155c2f16 100644
--- 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 51ec8e46f5f9..e933fb9fbf5c 100644
--- 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;