Merge branch 'timers-core-for-linus' of...

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

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  hrtimer: Make lookup table const
  RTC: Disable CONFIG_RTC_CLASS from being built as a module
  timers: Fix alarmtimer build issues when CONFIG_RTC_CLASS=n
  timers: Remove delayed irqwork from alarmtimers implementation
  timers: Improve alarmtimer comments and minor fixes
  timers: Posix interface for alarm-timers
  timers: Introduce in-kernel alarm-timer interface
  timers: Add rb_init_node() to allow for stack allocated rb nodes
  time: Add timekeeping_inject_sleeptime

drivers/rtc/Kconfig

@@ -3,10 +3,10 @@
 #
 
 config RTC_LIB
-	tristate
+	bool
 
 menuconfig RTC_CLASS
-	tristate "Real Time Clock"
+	bool "Real Time Clock"
 	default n
 	depends on !S390
 	select RTC_LIB
@@ -15,9 +15,6 @@ menuconfig RTC_CLASS
  	  be allowed to plug one or more RTCs to your system. You will
 	  probably want to enable one or more of the interfaces below.
 
-	  This driver can also be built as a module. If so, the module
-	  will be called rtc-core.
-
 if RTC_CLASS
 
 config RTC_HCTOSYS

drivers/rtc/class.c

@@ -41,26 +41,21 @@ static void rtc_device_release(struct device *dev)
  * system's wall clock; restore it on resume().
  */
 
-static struct timespec	delta;
 static time_t		oldtime;
+static struct timespec	oldts;
 
 static int rtc_suspend(struct device *dev, pm_message_t mesg)
 {
 	struct rtc_device	*rtc = to_rtc_device(dev);
 	struct rtc_time		tm;
-	struct timespec		ts = current_kernel_time();
 
 	if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)
 		return 0;
 
 	rtc_read_time(rtc, &tm);
+	ktime_get_ts(&oldts);
 	rtc_tm_to_time(&tm, &oldtime);
 
-	/* RTC precision is 1 second; adjust delta for avg 1/2 sec err */
-	set_normalized_timespec(&delta,
-				ts.tv_sec - oldtime,
-				ts.tv_nsec - (NSEC_PER_SEC >> 1));
-
 	return 0;
 }
 
@@ -70,10 +65,12 @@ static int rtc_resume(struct device *dev)
 	struct rtc_time		tm;
 	time_t			newtime;
 	struct timespec		time;
+	struct timespec		newts;
 
 	if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)
 		return 0;
 
+	ktime_get_ts(&newts);
 	rtc_read_time(rtc, &tm);
 	if (rtc_valid_tm(&tm) != 0) {
 		pr_debug("%s:  bogus resume time\n", dev_name(&rtc->dev));
@@ -85,15 +82,13 @@ static int rtc_resume(struct device *dev)
 			pr_debug("%s:  time travel!\n", dev_name(&rtc->dev));
 		return 0;
 	}
+	/* calculate the RTC time delta */
+	set_normalized_timespec(&time, newtime - oldtime, 0);
 
-	/* restore wall clock using delta against this RTC;
-	 * adjust again for avg 1/2 second RTC sampling error
-	 */
-	set_normalized_timespec(&time,
-				newtime + delta.tv_sec,
-				(NSEC_PER_SEC >> 1) + delta.tv_nsec);
-	do_settimeofday(&time);
+	/* subtract kernel time between rtc_suspend to rtc_resume */
+	time = timespec_sub(time, timespec_sub(newts, oldts));
 
+	timekeeping_inject_sleeptime(&time);
 	return 0;
 }
 

include/linux/alarmtimer.h

+#ifndef _LINUX_ALARMTIMER_H
+#define _LINUX_ALARMTIMER_H
+
+#include <linux/time.h>
+#include <linux/hrtimer.h>
+#include <linux/timerqueue.h>
+#include <linux/rtc.h>
+
+enum alarmtimer_type {
+	ALARM_REALTIME,
+	ALARM_BOOTTIME,
+
+	ALARM_NUMTYPE,
+};
+
+/**
+ * struct alarm - Alarm timer structure
+ * @node:	timerqueue node for adding to the event list this value
+ *		also includes the expiration time.
+ * @period:	Period for recuring alarms
+ * @function:	Function pointer to be executed when the timer fires.
+ * @type:	Alarm type (BOOTTIME/REALTIME)
+ * @enabled:	Flag that represents if the alarm is set to fire or not
+ * @data:	Internal data value.
+ */
+struct alarm {
+	struct timerqueue_node	node;
+	ktime_t			period;
+	void			(*function)(struct alarm *);
+	enum alarmtimer_type	type;
+	bool			enabled;
+	void			*data;
+};
+
+void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
+		void (*function)(struct alarm *));
+void alarm_start(struct alarm *alarm, ktime_t start, ktime_t period);
+void alarm_cancel(struct alarm *alarm);
+
+#endif

include/linux/capability.h

@@ -355,7 +355,12 @@ struct cpu_vfs_cap_data {
 
 #define CAP_SYSLOG           34
 
-#define CAP_LAST_CAP         CAP_SYSLOG
+/* Allow triggering something that will wake the system */
+
+#define CAP_WAKE_ALARM            35
+
+
+#define CAP_LAST_CAP         CAP_WAKE_ALARM
 
 #define cap_valid(x) ((x) >= 0 && (x) <= CAP_LAST_CAP)
 

include/linux/posix-timers.h

@@ -5,6 +5,7 @@
 #include <linux/list.h>
 #include <linux/sched.h>
 #include <linux/timex.h>
+#include <linux/alarmtimer.h>
 
 union cpu_time_count {
 	cputime_t cpu;
@@ -80,6 +81,7 @@ struct k_itimer {
 			unsigned long incr;
 			unsigned long expires;
 		} mmtimer;
+		struct alarm alarmtimer;
 	} it;
 };
 

include/linux/rbtree.h

@@ -136,6 +136,14 @@ static inline void rb_set_color(struct rb_node *rb, int color)
 #define RB_EMPTY_NODE(node)	(rb_parent(node) == node)
 #define RB_CLEAR_NODE(node)	(rb_set_parent(node, node))
 
+static inline void rb_init_node(struct rb_node *rb)
+{
+	rb->rb_parent_color = 0;
+	rb->rb_right = NULL;
+	rb->rb_left = NULL;
+	RB_CLEAR_NODE(rb);
+}
+
 extern void rb_insert_color(struct rb_node *, struct rb_root *);
 extern void rb_erase(struct rb_node *, struct rb_root *);
 

include/linux/time.h

@@ -126,6 +126,7 @@ struct timespec __current_kernel_time(void); /* does not take xtime_lock */
 struct timespec get_monotonic_coarse(void);
 void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
 				struct timespec *wtom, struct timespec *sleep);
+void timekeeping_inject_sleeptime(struct timespec *delta);
 
 #define CURRENT_TIME		(current_kernel_time())
 #define CURRENT_TIME_SEC	((struct timespec) { get_seconds(), 0 })
@@ -294,6 +295,8 @@ struct itimerval {
 #define CLOCK_REALTIME_COARSE		5
 #define CLOCK_MONOTONIC_COARSE		6
 #define CLOCK_BOOTTIME			7
+#define CLOCK_REALTIME_ALARM		8
+#define CLOCK_BOOTTIME_ALARM		9
 
 /*
  * The IDs of various hardware clocks:

include/linux/timerqueue.h

@@ -39,7 +39,7 @@ struct timerqueue_node *timerqueue_getnext(struct timerqueue_head *head)
 
 static inline void timerqueue_init(struct timerqueue_node *node)
 {
-	RB_CLEAR_NODE(&node->node);
+	rb_init_node(&node->node);
 }
 
 static inline void timerqueue_init_head(struct timerqueue_head *head)

kernel/hrtimer.c

@@ -81,7 +81,7 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
 	}
 };
 
-static int hrtimer_clock_to_base_table[MAX_CLOCKS] = {
+static const int hrtimer_clock_to_base_table[MAX_CLOCKS] = {
 	[CLOCK_REALTIME]	= HRTIMER_BASE_REALTIME,
 	[CLOCK_MONOTONIC]	= HRTIMER_BASE_MONOTONIC,
 	[CLOCK_BOOTTIME]	= HRTIMER_BASE_BOOTTIME,

kernel/time/Makefile

 obj-y += timekeeping.o ntp.o clocksource.o jiffies.o timer_list.o timecompare.o
-obj-y += timeconv.o posix-clock.o
+obj-y += timeconv.o posix-clock.o alarmtimer.o
 
 obj-$(CONFIG_GENERIC_CLOCKEVENTS_BUILD)		+= clockevents.o
 obj-$(CONFIG_GENERIC_CLOCKEVENTS)		+= tick-common.o

kernel/time/timekeeping.c

@@ -595,6 +595,58 @@ void __init timekeeping_init(void)
 /* time in seconds when suspend began */
 static struct timespec timekeeping_suspend_time;
 
+/**
+ * __timekeeping_inject_sleeptime - Internal function to add sleep interval
+ * @delta: pointer to a timespec delta value
+ *
+ * Takes a timespec offset measuring a suspend interval and properly
+ * adds the sleep offset to the timekeeping variables.
+ */
+static void __timekeeping_inject_sleeptime(struct timespec *delta)
+{
+	xtime = timespec_add(xtime, *delta);
+	wall_to_monotonic = timespec_sub(wall_to_monotonic, *delta);
+	total_sleep_time = timespec_add(total_sleep_time, *delta);
+}
+
+
+/**
+ * timekeeping_inject_sleeptime - Adds suspend interval to timeekeeping values
+ * @delta: pointer to a timespec delta value
+ *
+ * This hook is for architectures that cannot support read_persistent_clock
+ * because their RTC/persistent clock is only accessible when irqs are enabled.
+ *
+ * This function should only be called by rtc_resume(), and allows
+ * a suspend offset to be injected into the timekeeping values.
+ */
+void timekeeping_inject_sleeptime(struct timespec *delta)
+{
+	unsigned long flags;
+	struct timespec ts;
+
+	/* Make sure we don't set the clock twice */
+	read_persistent_clock(&ts);
+	if (!(ts.tv_sec == 0 && ts.tv_nsec == 0))
+		return;
+
+	write_seqlock_irqsave(&xtime_lock, flags);
+	timekeeping_forward_now();
+
+	__timekeeping_inject_sleeptime(delta);
+
+	timekeeper.ntp_error = 0;
+	ntp_clear();
+	update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
+				timekeeper.mult);
+
+	write_sequnlock_irqrestore(&xtime_lock, flags);
+
+	/* signal hrtimers about time change */
+	clock_was_set();
+}
+
+
 /**
  * timekeeping_resume - Resumes the generic timekeeping subsystem.
  *
@@ -615,9 +667,7 @@ static void timekeeping_resume(void)
 
 	if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) {
 		ts = timespec_sub(ts, timekeeping_suspend_time);
-		xtime = timespec_add(xtime, ts);
-		wall_to_monotonic = timespec_sub(wall_to_monotonic, ts);
-		total_sleep_time = timespec_add(total_sleep_time, ts);
+		__timekeeping_inject_sleeptime(&ts);
 	}
 	/* re-base the last cycle value */
 	timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);