Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm

[linux-2.6] / kernel / time / timekeeping.c

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 89698776613eb5c51d6dca9d385abc0dc0422bc3..4ad79f6bdec6b76fb144833ad33b13f73c91c8a6 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 */
 
 
@@ -205,6 +217,7 @@ static void change_clocksource(void)
 }
 #else
 static inline void change_clocksource(void) { }
+static inline s64 __get_nsec_offset(void) { return 0; }
 #endif
 
 /**
@@ -268,6 +281,8 @@ void __init timekeeping_init(void)
 static int timekeeping_suspended;
 /* time in seconds when suspend began */
 static unsigned long timekeeping_suspend_time;
+/* xtime offset when we went into suspend */
+static s64 timekeeping_suspend_nsecs;
 
 /**
  * timekeeping_resume - Resumes the generic timekeeping subsystem.
@@ -293,6 +308,8 @@ static int timekeeping_resume(struct sys_device *dev)
                wall_to_monotonic.tv_sec -= sleep_length;
                total_sleep_time += sleep_length;
        }
+       /* Make sure that we have the correct xtime reference */
+       timespec_add_ns(&xtime, timekeeping_suspend_nsecs);
        /* re-base the last cycle value */
        clock->cycle_last = clocksource_read(clock);
        clock->error = 0;
@@ -313,9 +330,12 @@ 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);
+       /* Get the current xtime offset */
+       timekeeping_suspend_nsecs = __get_nsec_offset();
        timekeeping_suspended = 1;
-       timekeeping_suspend_time = read_persistent_clock();
        write_sequnlock_irqrestore(&xtime_lock, flags);
 
        clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL);
@@ -466,10 +486,6 @@ 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 +498,8 @@ 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 +531,25 @@ 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);