timekeeping: access rtc outside of xtime lock

[pandora-kernel.git] / kernel / time / timekeeping.c

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 8969877..f682091 100644 (file)
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -47,10 +47,22 @@ EXPORT_SYMBOL(xtime_lock);
 struct timespec xtime __attribute__ ((aligned (16)));
 struct timespec wall_to_monotonic __attribute__ ((aligned (16)));
 static unsigned long total_sleep_time;         /* seconds */
-
 EXPORT_SYMBOL(xtime);
 
 
+#ifdef CONFIG_NO_HZ
+static struct timespec xtime_cache __attribute__ ((aligned (16)));
+static inline void update_xtime_cache(u64 nsec)
+{
+       xtime_cache = xtime;
+       timespec_add_ns(&xtime_cache, nsec);
+}
+#else
+#define xtime_cache xtime
+/* We do *not* want to evaluate the argument for this case */
+#define update_xtime_cache(n) do { } while (0)
+#endif
+
 static struct clocksource *clock; /* pointer to current clocksource */
 
 
@@ -313,9 +325,10 @@ static int timekeeping_suspend(struct sys_device *dev, pm_message_t state)
 {
        unsigned long flags;
 
+       timekeeping_suspend_time = read_persistent_clock();
+
        write_seqlock_irqsave(&xtime_lock, flags);
        timekeeping_suspended = 1;
-       timekeeping_suspend_time = read_persistent_clock();
        write_sequnlock_irqrestore(&xtime_lock, flags);
 
        clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL);
@@ -466,10 +479,6 @@ void update_wall_time(void)
                        second_overflow();
                }
 
-               /* interpolator bits */
-               time_interpolator_update(clock->xtime_interval
-                                               >> clock->shift);
-
                /* accumulate error between NTP and clock interval */
                clock->error += current_tick_length();
                clock->error -= clock->xtime_interval << (TICK_LENGTH_SHIFT - clock->shift);
@@ -482,6 +491,8 @@ void update_wall_time(void)
        xtime.tv_nsec = (s64)clock->xtime_nsec >> clock->shift;
        clock->xtime_nsec -= (s64)xtime.tv_nsec << clock->shift;
 
+       update_xtime_cache(cyc2ns(clock, offset));
+
        /* check to see if there is a new clocksource to use */
        change_clocksource();
        update_vsyscall(&xtime, clock);
@@ -513,3 +524,25 @@ void monotonic_to_bootbased(struct timespec *ts)
 {
        ts->tv_sec += total_sleep_time;
 }
+
+unsigned long get_seconds(void)
+{
+       return xtime_cache.tv_sec;
+}
+EXPORT_SYMBOL(get_seconds);
+
+
+struct timespec current_kernel_time(void)
+{
+       struct timespec now;
+       unsigned long seq;
+
+       do {
+               seq = read_seqbegin(&xtime_lock);
+
+               now = xtime_cache;
+       } while (read_seqretry(&xtime_lock, seq));
+
+       return now;
+}
+EXPORT_SYMBOL(current_kernel_time);