Merge branch 'timers-timekeeping-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'timers-timekeeping-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  um: Fix read_persistent_clock fallout
  kgdb: Do not access xtime directly
  powerpc: Clean up obsolete code relating to decrementer and timebase
  powerpc: Rework VDSO gettimeofday to prevent time going backwards
  clocksource: Add __clocksource_updatefreq_hz/khz methods
  x86: Convert common clocksources to use clocksource_register_hz/khz
  timekeeping: Make xtime and wall_to_monotonic static
  hrtimer: Cleanup direct access to wall_to_monotonic
  um: Convert to use read_persistent_clock
  timkeeping: Fix update_vsyscall to provide wall_to_monotonic offset
  powerpc: Cleanup xtime usage
  powerpc: Simplify update_vsyscall
  time: Kill off CONFIG_GENERIC_TIME
  time: Implement timespec_add
  x86: Fix vtime/file timestamp inconsistencies

Trivial conflicts in Documentation/feature-removal-schedule.txt

Much less trivial conflicts in arch/powerpc/kernel/time.c resolved as
per Thomas' earlier merge commit 47916be4e2 ("Merge branch
'powerpc.cherry-picks' into timers/clocksource")

kernel/debug/kdb/kdb_main.c

@@ -2548,6 +2548,7 @@ static void kdb_sysinfo(struct sysinfo *val)
  */
 static int kdb_summary(int argc, const char **argv)
 {
+	struct timespec now;
 	struct kdb_tm tm;
 	struct sysinfo val;
 
@@ -2562,7 +2563,8 @@ static int kdb_summary(int argc, const char **argv)
 	kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
 	kdb_printf("ccversion  %s\n", __stringify(CCVERSION));
 
-	kdb_gmtime(&xtime, &tm);
+	now = __current_kernel_time();
+	kdb_gmtime(&now, &tm);
 	kdb_printf("date       %04d-%02d-%02d %02d:%02d:%02d "
 		   "tz_minuteswest %d\n",
 		1900+tm.tm_year, tm.tm_mon+1, tm.tm_mday,

kernel/hrtimer.c

@@ -90,7 +90,7 @@ static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base)
 	do {
 		seq = read_seqbegin(&xtime_lock);
 		xts = __current_kernel_time();
-		tom = wall_to_monotonic;
+		tom = __get_wall_to_monotonic();
 	} while (read_seqretry(&xtime_lock, seq));
 
 	xtim = timespec_to_ktime(xts);
@@ -608,7 +608,7 @@ static int hrtimer_reprogram(struct hrtimer *timer,
 static void retrigger_next_event(void *arg)
 {
 	struct hrtimer_cpu_base *base;
-	struct timespec realtime_offset;
+	struct timespec realtime_offset, wtm;
 	unsigned long seq;
 
 	if (!hrtimer_hres_active())
@@ -616,10 +616,9 @@ static void retrigger_next_event(void *arg)
 
 	do {
 		seq = read_seqbegin(&xtime_lock);
-		set_normalized_timespec(&realtime_offset,
-					-wall_to_monotonic.tv_sec,
-					-wall_to_monotonic.tv_nsec);
+		wtm = __get_wall_to_monotonic();
 	} while (read_seqretry(&xtime_lock, seq));
+	set_normalized_timespec(&realtime_offset, -wtm.tv_sec, -wtm.tv_nsec);
 
 	base = &__get_cpu_var(hrtimer_bases);
 

kernel/time.c

@@ -300,22 +300,6 @@ struct timespec timespec_trunc(struct timespec t, unsigned gran)
 }
 EXPORT_SYMBOL(timespec_trunc);
 
-#ifndef CONFIG_GENERIC_TIME
-/*
- * Simulate gettimeofday using do_gettimeofday which only allows a timeval
- * and therefore only yields usec accuracy
- */
-void getnstimeofday(struct timespec *tv)
-{
-	struct timeval x;
-
-	do_gettimeofday(&x);
-	tv->tv_sec = x.tv_sec;
-	tv->tv_nsec = x.tv_usec * NSEC_PER_USEC;
-}
-EXPORT_SYMBOL_GPL(getnstimeofday);
-#endif
-
 /* Converts Gregorian date to seconds since 1970-01-01 00:00:00.
  * Assumes input in normal date format, i.e. 1980-12-31 23:59:59
  * => year=1980, mon=12, day=31, hour=23, min=59, sec=59.

kernel/time/Kconfig

@@ -6,7 +6,7 @@ config TICK_ONESHOT
 
 config NO_HZ
 	bool "Tickless System (Dynamic Ticks)"
-	depends on GENERIC_TIME && GENERIC_CLOCKEVENTS
+	depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS
 	select TICK_ONESHOT
 	help
 	  This option enables a tickless system: timer interrupts will
@@ -15,7 +15,7 @@ config NO_HZ
 
 config HIGH_RES_TIMERS
 	bool "High Resolution Timer Support"
-	depends on GENERIC_TIME && GENERIC_CLOCKEVENTS
+	depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS
 	select TICK_ONESHOT
 	help
 	  This option enables high resolution timer support. If your

kernel/time/clocksource.c

@@ -531,7 +531,7 @@ static u64 clocksource_max_deferment(struct clocksource *cs)
 	return max_nsecs - (max_nsecs >> 5);
 }
 
-#ifdef CONFIG_GENERIC_TIME
+#ifndef CONFIG_ARCH_USES_GETTIMEOFFSET
 
 /**
  * clocksource_select - Select the best clocksource available
@@ -577,7 +577,7 @@ static void clocksource_select(void)
 	}
 }
 
-#else /* CONFIG_GENERIC_TIME */
+#else /* !CONFIG_ARCH_USES_GETTIMEOFFSET */
 
 static inline void clocksource_select(void) { }
 
@@ -638,6 +638,32 @@ static void clocksource_enqueue(struct clocksource *cs)
  */
 #define MAX_UPDATE_LENGTH 5 /* Seconds */
 
+/**
+ * __clocksource_updatefreq_scale - Used update clocksource with new freq
+ * @t:		clocksource to be registered
+ * @scale:	Scale factor multiplied against freq to get clocksource hz
+ * @freq:	clocksource frequency (cycles per second) divided by scale
+ *
+ * This should only be called from the clocksource->enable() method.
+ *
+ * This *SHOULD NOT* be called directly! Please use the
+ * clocksource_updatefreq_hz() or clocksource_updatefreq_khz helper functions.
+ */
+void __clocksource_updatefreq_scale(struct clocksource *cs, u32 scale, u32 freq)
+{
+	/*
+	 * Ideally we want to use  some of the limits used in
+	 * clocksource_max_deferment, to provide a more informed
+	 * MAX_UPDATE_LENGTH. But for now this just gets the
+	 * register interface working properly.
+	 */
+	clocks_calc_mult_shift(&cs->mult, &cs->shift, freq,
+				      NSEC_PER_SEC/scale,
+				      MAX_UPDATE_LENGTH*scale);
+	cs->max_idle_ns = clocksource_max_deferment(cs);
+}
+EXPORT_SYMBOL_GPL(__clocksource_updatefreq_scale);
+
 /**
  * __clocksource_register_scale - Used to install new clocksources
  * @t:		clocksource to be registered
@@ -652,17 +678,10 @@ static void clocksource_enqueue(struct clocksource *cs)
 int __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq)
 {
 
-	/*
-	 * Ideally we want to use  some of the limits used in
-	 * clocksource_max_deferment, to provide a more informed
-	 * MAX_UPDATE_LENGTH. But for now this just gets the
-	 * register interface working properly.
-	 */
-	clocks_calc_mult_shift(&cs->mult, &cs->shift, freq,
-				      NSEC_PER_SEC/scale,
-				      MAX_UPDATE_LENGTH*scale);
-	cs->max_idle_ns = clocksource_max_deferment(cs);
+	/* Intialize mult/shift and max_idle_ns */
+	__clocksource_updatefreq_scale(cs, scale, freq);
 
+	/* Add clocksource to the clcoksource list */
 	mutex_lock(&clocksource_mutex);
 	clocksource_enqueue(cs);
 	clocksource_select();

kernel/time/timekeeping.c

@@ -153,8 +153,8 @@ __cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock);
  * - wall_to_monotonic is no longer the boot time, getboottime must be
  * used instead.
  */
-struct timespec xtime __attribute__ ((aligned (16)));
-struct timespec wall_to_monotonic __attribute__ ((aligned (16)));
+static struct timespec xtime __attribute__ ((aligned (16)));
+static struct timespec wall_to_monotonic __attribute__ ((aligned (16)));
 static struct timespec total_sleep_time;
 
 /*
@@ -170,11 +170,10 @@ void timekeeping_leap_insert(int leapsecond)
 {
 	xtime.tv_sec += leapsecond;
 	wall_to_monotonic.tv_sec -= leapsecond;
-	update_vsyscall(&xtime, timekeeper.clock, timekeeper.mult);
+	update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
+			timekeeper.mult);
 }
 
-#ifdef CONFIG_GENERIC_TIME
-
 /**
  * timekeeping_forward_now - update clock to the current time
  *
@@ -328,7 +327,8 @@ int do_settimeofday(struct timespec *tv)
 	timekeeper.ntp_error = 0;
 	ntp_clear();
 
-	update_vsyscall(&xtime, timekeeper.clock, timekeeper.mult);
+	update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
+				timekeeper.mult);
 
 	write_sequnlock_irqrestore(&xtime_lock, flags);
 
@@ -376,52 +376,6 @@ void timekeeping_notify(struct clocksource *clock)
 	tick_clock_notify();
 }
 
-#else /* GENERIC_TIME */
-
-static inline void timekeeping_forward_now(void) { }
-
-/**
- * ktime_get - get the monotonic time in ktime_t format
- *
- * returns the time in ktime_t format
- */
-ktime_t ktime_get(void)
-{
-	struct timespec now;
-
-	ktime_get_ts(&now);
-
-	return timespec_to_ktime(now);
-}
-EXPORT_SYMBOL_GPL(ktime_get);
-
-/**
- * ktime_get_ts - get the monotonic clock in timespec format
- * @ts:		pointer to timespec variable
- *
- * The function calculates the monotonic clock from the realtime
- * clock and the wall_to_monotonic offset and stores the result
- * in normalized timespec format in the variable pointed to by @ts.
- */
-void ktime_get_ts(struct timespec *ts)
-{
-	struct timespec tomono;
-	unsigned long seq;
-
-	do {
-		seq = read_seqbegin(&xtime_lock);
-		getnstimeofday(ts);
-		tomono = wall_to_monotonic;
-
-	} while (read_seqretry(&xtime_lock, seq));
-
-	set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
-				ts->tv_nsec + tomono.tv_nsec);
-}
-EXPORT_SYMBOL_GPL(ktime_get_ts);
-
-#endif /* !GENERIC_TIME */
-
 /**
  * ktime_get_real - get the real (wall-) time in ktime_t format
  *
@@ -579,9 +533,9 @@ static int timekeeping_resume(struct sys_device *dev)
 
 	if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) {
 		ts = timespec_sub(ts, timekeeping_suspend_time);
-		xtime = timespec_add_safe(xtime, ts);
+		xtime = timespec_add(xtime, ts);
 		wall_to_monotonic = timespec_sub(wall_to_monotonic, ts);
-		total_sleep_time = timespec_add_safe(total_sleep_time, ts);
+		total_sleep_time = timespec_add(total_sleep_time, ts);
 	}
 	/* re-base the last cycle value */
 	timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);
@@ -784,10 +738,11 @@ void update_wall_time(void)
 		return;
 
 	clock = timekeeper.clock;
-#ifdef CONFIG_GENERIC_TIME
-	offset = (clock->read(clock) - clock->cycle_last) & clock->mask;
-#else
+
+#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
 	offset = timekeeper.cycle_interval;
+#else
+	offset = (clock->read(clock) - clock->cycle_last) & clock->mask;
 #endif
 	timekeeper.xtime_nsec = (s64)xtime.tv_nsec << timekeeper.shift;
 
@@ -856,7 +811,8 @@ void update_wall_time(void)
 	}
 
 	/* check to see if there is a new clocksource to use */
-	update_vsyscall(&xtime, timekeeper.clock, timekeeper.mult);
+	update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
+				timekeeper.mult);
 }
 
 /**
@@ -887,7 +843,7 @@ EXPORT_SYMBOL_GPL(getboottime);
  */
 void monotonic_to_bootbased(struct timespec *ts)
 {
-	*ts = timespec_add_safe(*ts, total_sleep_time);
+	*ts = timespec_add(*ts, total_sleep_time);
 }
 EXPORT_SYMBOL_GPL(monotonic_to_bootbased);
 
@@ -902,6 +858,11 @@ struct timespec __current_kernel_time(void)
 	return xtime;
 }
 
+struct timespec __get_wall_to_monotonic(void)
+{
+	return wall_to_monotonic;
+}
+
 struct timespec current_kernel_time(void)
 {
 	struct timespec now;

kernel/trace/Kconfig

@@ -153,7 +153,7 @@ config IRQSOFF_TRACER
 	bool "Interrupts-off Latency Tracer"
 	default n
 	depends on TRACE_IRQFLAGS_SUPPORT
-	depends on GENERIC_TIME
+	depends on !ARCH_USES_GETTIMEOFFSET
 	select TRACE_IRQFLAGS
 	select GENERIC_TRACER
 	select TRACER_MAX_TRACE
@@ -175,7 +175,7 @@ config IRQSOFF_TRACER
 config PREEMPT_TRACER
 	bool "Preemption-off Latency Tracer"
 	default n
-	depends on GENERIC_TIME
+	depends on !ARCH_USES_GETTIMEOFFSET
 	depends on PREEMPT
 	select GENERIC_TRACER
 	select TRACER_MAX_TRACE