Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

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

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 07a3f1420c27fa06fedf7d18e7a33e7b99aa2c03..e5e466b2759893ccd21cea1e2242b8fbf7dac9a5 100644 (file)
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -24,9 +24,7 @@
  * This read-write spinlock protects us from races in SMP while
  * playing with xtime and avenrun.
  */
-__attribute__((weak)) __cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock);
-
-EXPORT_SYMBOL(xtime_lock);
+__cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock);
 
 
 /*
@@ -48,8 +46,12 @@ struct timespec xtime __attribute__ ((aligned (16)));
 struct timespec wall_to_monotonic __attribute__ ((aligned (16)));
 static unsigned long total_sleep_time;         /* seconds */
 
-EXPORT_SYMBOL(xtime);
-
+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);
+}
 
 static struct clocksource *clock; /* pointer to current clocksource */
 
@@ -205,6 +207,7 @@ static void change_clocksource(void)
 }
 #else
 static inline void change_clocksource(void) { }
+static inline s64 __get_nsec_offset(void) { return 0; }
 #endif
 
 /**
@@ -268,6 +271,8 @@ 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 +298,8 @@ 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 +320,12 @@ 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);
@@ -478,6 +488,8 @@ 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);
@@ -510,6 +522,13 @@ 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;
@@ -518,10 +537,9 @@ struct timespec current_kernel_time(void)
        do {
                seq = read_seqbegin(&xtime_lock);
 
-               now = xtime;
+               now = xtime_cache;
        } while (read_seqretry(&xtime_lock, seq));
 
        return now;
 }
-
 EXPORT_SYMBOL(current_kernel_time);