[PATCH] fix next_timer_interrupt() for hrtimer
[pandora-kernel.git] / kernel / timer.c
index 6ed1a82..8256f3f 100644 (file)
@@ -33,6 +33,7 @@
 #include <linux/posix-timers.h>
 #include <linux/cpu.h>
 #include <linux/syscalls.h>
+#include <linux/delay.h>
 
 #include <asm/uaccess.h>
 #include <asm/unistd.h>
@@ -46,6 +47,10 @@ static void time_interpolator_update(long delta_nsec);
 #define time_interpolator_update(x)
 #endif
 
+u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
+
+EXPORT_SYMBOL(jiffies_64);
+
 /*
  * per-CPU timer vector definitions:
  */
@@ -91,30 +96,6 @@ static inline void set_running_timer(tvec_base_t *base,
 #endif
 }
 
-static void check_timer_failed(struct timer_list *timer)
-{
-       static int whine_count;
-       if (whine_count < 16) {
-               whine_count++;
-               printk("Uninitialised timer!\n");
-               printk("This is just a warning.  Your computer is OK\n");
-               printk("function=0x%p, data=0x%lx\n",
-                       timer->function, timer->data);
-               dump_stack();
-       }
-       /*
-        * Now fix it up
-        */
-       timer->magic = TIMER_MAGIC;
-}
-
-static inline void check_timer(struct timer_list *timer)
-{
-       if (timer->magic != TIMER_MAGIC)
-               check_timer_failed(timer);
-}
-
-
 static void internal_add_timer(tvec_base_t *base, struct timer_list *timer)
 {
        unsigned long expires = timer->expires;
@@ -177,7 +158,6 @@ void fastcall init_timer(struct timer_list *timer)
 {
        timer->entry.next = NULL;
        timer->base = &per_cpu(tvec_bases, raw_smp_processor_id()).t_base;
-       timer->magic = TIMER_MAGIC;
 }
 EXPORT_SYMBOL(init_timer);
 
@@ -230,7 +210,6 @@ int __mod_timer(struct timer_list *timer, unsigned long expires)
        int ret = 0;
 
        BUG_ON(!timer->function);
-       check_timer(timer);
 
        base = lock_timer_base(timer, &flags);
 
@@ -283,9 +262,6 @@ void add_timer_on(struct timer_list *timer, int cpu)
        unsigned long flags;
 
        BUG_ON(timer_pending(timer) || !timer->function);
-
-       check_timer(timer);
-
        spin_lock_irqsave(&base->t_base.lock, flags);
        timer->base = &base->t_base;
        internal_add_timer(base, timer);
@@ -316,8 +292,6 @@ int mod_timer(struct timer_list *timer, unsigned long expires)
 {
        BUG_ON(!timer->function);
 
-       check_timer(timer);
-
        /*
         * This is a common optimization triggered by the
         * networking code - if the timer is re-modified
@@ -348,8 +322,6 @@ int del_timer(struct timer_list *timer)
        unsigned long flags;
        int ret = 0;
 
-       check_timer(timer);
-
        if (timer_pending(timer)) {
                base = lock_timer_base(timer, &flags);
                if (timer_pending(timer)) {
@@ -412,8 +384,6 @@ out:
  */
 int del_timer_sync(struct timer_list *timer)
 {
-       check_timer(timer);
-
        for (;;) {
                int ret = try_to_del_timer_sync(timer);
                if (ret >= 0)
@@ -519,13 +489,25 @@ unsigned long next_timer_interrupt(void)
        struct list_head *list;
        struct timer_list *nte;
        unsigned long expires;
+       unsigned long hr_expires = MAX_JIFFY_OFFSET;
+       ktime_t hr_delta;
        tvec_t *varray[4];
        int i, j;
 
+       hr_delta = hrtimer_get_next_event();
+       if (hr_delta.tv64 != KTIME_MAX) {
+               struct timespec tsdelta;
+               tsdelta = ktime_to_timespec(hr_delta);
+               hr_expires = timespec_to_jiffies(&tsdelta);
+               if (hr_expires < 3)
+                       return hr_expires + jiffies;
+       }
+       hr_expires += jiffies;
+
        base = &__get_cpu_var(tvec_bases);
        spin_lock(&base->t_base.lock);
        expires = base->timer_jiffies + (LONG_MAX >> 1);
-       list = 0;
+       list = NULL;
 
        /* Look for timer events in tv1. */
        j = base->timer_jiffies & TVR_MASK;
@@ -572,6 +554,10 @@ found:
                }
        }
        spin_unlock(&base->t_base.lock);
+
+       if (time_before(hr_expires, expires))
+               return hr_expires;
+
        return expires;
 }
 #endif
@@ -632,182 +618,162 @@ long time_next_adjust;
  */
 static void second_overflow(void)
 {
-    long ltemp;
-
-    /* Bump the maxerror field */
-    time_maxerror += time_tolerance >> SHIFT_USEC;
-    if ( time_maxerror > NTP_PHASE_LIMIT ) {
-       time_maxerror = NTP_PHASE_LIMIT;
-       time_status |= STA_UNSYNC;
-    }
-
-    /*
-     * Leap second processing. If in leap-insert state at
-     * the end of the day, the system clock is set back one
-     * second; if in leap-delete state, the system clock is
-     * set ahead one second. The microtime() routine or
-     * external clock driver will insure that reported time
-     * is always monotonic. The ugly divides should be
-     * replaced.
-     */
-    switch (time_state) {
-
-    case TIME_OK:
-       if (time_status & STA_INS)
-           time_state = TIME_INS;
-       else if (time_status & STA_DEL)
-           time_state = TIME_DEL;
-       break;
-
-    case TIME_INS:
-       if (xtime.tv_sec % 86400 == 0) {
-           xtime.tv_sec--;
-           wall_to_monotonic.tv_sec++;
-           /* The timer interpolator will make time change gradually instead
-            * of an immediate jump by one second.
-            */
-           time_interpolator_update(-NSEC_PER_SEC);
-           time_state = TIME_OOP;
-           clock_was_set();
-           printk(KERN_NOTICE "Clock: inserting leap second 23:59:60 UTC\n");
+       long ltemp;
+
+       /* Bump the maxerror field */
+       time_maxerror += time_tolerance >> SHIFT_USEC;
+       if (time_maxerror > NTP_PHASE_LIMIT) {
+               time_maxerror = NTP_PHASE_LIMIT;
+               time_status |= STA_UNSYNC;
        }
-       break;
-
-    case TIME_DEL:
-       if ((xtime.tv_sec + 1) % 86400 == 0) {
-           xtime.tv_sec++;
-           wall_to_monotonic.tv_sec--;
-           /* Use of time interpolator for a gradual change of time */
-           time_interpolator_update(NSEC_PER_SEC);
-           time_state = TIME_WAIT;
-           clock_was_set();
-           printk(KERN_NOTICE "Clock: deleting leap second 23:59:59 UTC\n");
+
+       /*
+        * Leap second processing. If in leap-insert state at the end of the
+        * day, the system clock is set back one second; if in leap-delete
+        * state, the system clock is set ahead one second. The microtime()
+        * routine or external clock driver will insure that reported time is
+        * always monotonic. The ugly divides should be replaced.
+        */
+       switch (time_state) {
+       case TIME_OK:
+               if (time_status & STA_INS)
+                       time_state = TIME_INS;
+               else if (time_status & STA_DEL)
+                       time_state = TIME_DEL;
+               break;
+       case TIME_INS:
+               if (xtime.tv_sec % 86400 == 0) {
+                       xtime.tv_sec--;
+                       wall_to_monotonic.tv_sec++;
+                       /*
+                        * The timer interpolator will make time change
+                        * gradually instead of an immediate jump by one second
+                        */
+                       time_interpolator_update(-NSEC_PER_SEC);
+                       time_state = TIME_OOP;
+                       clock_was_set();
+                       printk(KERN_NOTICE "Clock: inserting leap second "
+                                       "23:59:60 UTC\n");
+               }
+               break;
+       case TIME_DEL:
+               if ((xtime.tv_sec + 1) % 86400 == 0) {
+                       xtime.tv_sec++;
+                       wall_to_monotonic.tv_sec--;
+                       /*
+                        * Use of time interpolator for a gradual change of
+                        * time
+                        */
+                       time_interpolator_update(NSEC_PER_SEC);
+                       time_state = TIME_WAIT;
+                       clock_was_set();
+                       printk(KERN_NOTICE "Clock: deleting leap second "
+                                       "23:59:59 UTC\n");
+               }
+               break;
+       case TIME_OOP:
+               time_state = TIME_WAIT;
+               break;
+       case TIME_WAIT:
+               if (!(time_status & (STA_INS | STA_DEL)))
+               time_state = TIME_OK;
        }
-       break;
-
-    case TIME_OOP:
-       time_state = TIME_WAIT;
-       break;
-
-    case TIME_WAIT:
-       if (!(time_status & (STA_INS | STA_DEL)))
-           time_state = TIME_OK;
-    }
-
-    /*
-     * Compute the phase adjustment for the next second. In
-     * PLL mode, the offset is reduced by a fixed factor
-     * times the time constant. In FLL mode the offset is
-     * used directly. In either mode, the maximum phase
-     * adjustment for each second is clamped so as to spread
-     * the adjustment over not more than the number of
-     * seconds between updates.
-     */
-    if (time_offset < 0) {
-       ltemp = -time_offset;
-       if (!(time_status & STA_FLL))
-           ltemp >>= SHIFT_KG + time_constant;
-       if (ltemp > (MAXPHASE / MINSEC) << SHIFT_UPDATE)
-           ltemp = (MAXPHASE / MINSEC) << SHIFT_UPDATE;
-       time_offset += ltemp;
-       time_adj = -ltemp << (SHIFT_SCALE - SHIFT_HZ - SHIFT_UPDATE);
-    } else {
+
+       /*
+        * Compute the phase adjustment for the next second. In PLL mode, the
+        * offset is reduced by a fixed factor times the time constant. In FLL
+        * mode the offset is used directly. In either mode, the maximum phase
+        * adjustment for each second is clamped so as to spread the adjustment
+        * over not more than the number of seconds between updates.
+        */
        ltemp = time_offset;
        if (!(time_status & STA_FLL))
-           ltemp >>= SHIFT_KG + time_constant;
-       if (ltemp > (MAXPHASE / MINSEC) << SHIFT_UPDATE)
-           ltemp = (MAXPHASE / MINSEC) << SHIFT_UPDATE;
+               ltemp = shift_right(ltemp, SHIFT_KG + time_constant);
+       ltemp = min(ltemp, (MAXPHASE / MINSEC) << SHIFT_UPDATE);
+       ltemp = max(ltemp, -(MAXPHASE / MINSEC) << SHIFT_UPDATE);
        time_offset -= ltemp;
        time_adj = ltemp << (SHIFT_SCALE - SHIFT_HZ - SHIFT_UPDATE);
-    }
-
-    /*
-     * Compute the frequency estimate and additional phase
-     * adjustment due to frequency error for the next
-     * second. When the PPS signal is engaged, gnaw on the
-     * watchdog counter and update the frequency computed by
-     * the pll and the PPS signal.
-     */
-    pps_valid++;
-    if (pps_valid == PPS_VALID) {      /* PPS signal lost */
-       pps_jitter = MAXTIME;
-       pps_stabil = MAXFREQ;
-       time_status &= ~(STA_PPSSIGNAL | STA_PPSJITTER |
-                        STA_PPSWANDER | STA_PPSERROR);
-    }
-    ltemp = time_freq + pps_freq;
-    if (ltemp < 0)
-       time_adj -= -ltemp >>
-           (SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE);
-    else
-       time_adj += ltemp >>
-           (SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE);
+
+       /*
+        * Compute the frequency estimate and additional phase adjustment due
+        * to frequency error for the next second. When the PPS signal is
+        * engaged, gnaw on the watchdog counter and update the frequency
+        * computed by the pll and the PPS signal.
+        */
+       pps_valid++;
+       if (pps_valid == PPS_VALID) {   /* PPS signal lost */
+               pps_jitter = MAXTIME;
+               pps_stabil = MAXFREQ;
+               time_status &= ~(STA_PPSSIGNAL | STA_PPSJITTER |
+                               STA_PPSWANDER | STA_PPSERROR);
+       }
+       ltemp = time_freq + pps_freq;
+       time_adj += shift_right(ltemp,(SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE));
 
 #if HZ == 100
-    /* Compensate for (HZ==100) != (1 << SHIFT_HZ).
-     * Add 25% and 3.125% to get 128.125; => only 0.125% error (p. 14)
-     */
-    if (time_adj < 0)
-       time_adj -= (-time_adj >> 2) + (-time_adj >> 5);
-    else
-       time_adj += (time_adj >> 2) + (time_adj >> 5);
+       /*
+        * Compensate for (HZ==100) != (1 << SHIFT_HZ).  Add 25% and 3.125% to
+        * get 128.125; => only 0.125% error (p. 14)
+        */
+       time_adj += shift_right(time_adj, 2) + shift_right(time_adj, 5);
 #endif
 #if HZ == 250
-    /* Compensate for (HZ==250) != (1 << SHIFT_HZ).
-     * Add 1.5625% and 0.78125% to get 255.85938; => only 0.05% error (p. 14)
-     */
-    if (time_adj < 0)
-       time_adj -= (-time_adj >> 6) + (-time_adj >> 7);
-    else
-       time_adj += (time_adj >> 6) + (time_adj >> 7);
+       /*
+        * Compensate for (HZ==250) != (1 << SHIFT_HZ).  Add 1.5625% and
+        * 0.78125% to get 255.85938; => only 0.05% error (p. 14)
+        */
+       time_adj += shift_right(time_adj, 6) + shift_right(time_adj, 7);
 #endif
 #if HZ == 1000
-    /* Compensate for (HZ==1000) != (1 << SHIFT_HZ).
-     * Add 1.5625% and 0.78125% to get 1023.4375; => only 0.05% error (p. 14)
-     */
-    if (time_adj < 0)
-       time_adj -= (-time_adj >> 6) + (-time_adj >> 7);
-    else
-       time_adj += (time_adj >> 6) + (time_adj >> 7);
+       /*
+        * Compensate for (HZ==1000) != (1 << SHIFT_HZ).  Add 1.5625% and
+        * 0.78125% to get 1023.4375; => only 0.05% error (p. 14)
+        */
+       time_adj += shift_right(time_adj, 6) + shift_right(time_adj, 7);
 #endif
 }
 
+/*
+ * Returns how many microseconds we need to add to xtime this tick
+ * in doing an adjustment requested with adjtime.
+ */
+static long adjtime_adjustment(void)
+{
+       long time_adjust_step;
+
+       time_adjust_step = time_adjust;
+       if (time_adjust_step) {
+               /*
+                * We are doing an adjtime thing.  Prepare time_adjust_step to
+                * be within bounds.  Note that a positive time_adjust means we
+                * want the clock to run faster.
+                *
+                * Limit the amount of the step to be in the range
+                * -tickadj .. +tickadj
+                */
+               time_adjust_step = min(time_adjust_step, (long)tickadj);
+               time_adjust_step = max(time_adjust_step, (long)-tickadj);
+       }
+       return time_adjust_step;
+}
+
 /* in the NTP reference this is called "hardclock()" */
 static void update_wall_time_one_tick(void)
 {
        long time_adjust_step, delta_nsec;
 
-       if ( (time_adjust_step = time_adjust) != 0 ) {
-           /* We are doing an adjtime thing. 
-            *
-            * Prepare time_adjust_step to be within bounds.
-            * Note that a positive time_adjust means we want the clock
-            * to run faster.
-            *
-            * Limit the amount of the step to be in the range
-            * -tickadj .. +tickadj
-            */
-            if (time_adjust > tickadj)
-               time_adjust_step = tickadj;
-            else if (time_adjust < -tickadj)
-               time_adjust_step = -tickadj;
-
-           /* Reduce by this step the amount of time left  */
-           time_adjust -= time_adjust_step;
-       }
+       time_adjust_step = adjtime_adjustment();
+       if (time_adjust_step)
+               /* Reduce by this step the amount of time left  */
+               time_adjust -= time_adjust_step;
        delta_nsec = tick_nsec + time_adjust_step * 1000;
        /*
         * Advance the phase, once it gets to one microsecond, then
         * advance the tick more.
         */
        time_phase += time_adj;
-       if (time_phase <= -FINENSEC) {
-               long ltemp = -time_phase >> (SHIFT_SCALE - 10);
-               time_phase += ltemp << (SHIFT_SCALE - 10);
-               delta_nsec -= ltemp;
-       }
-       else if (time_phase >= FINENSEC) {
-               long ltemp = time_phase >> (SHIFT_SCALE - 10);
+       if ((time_phase >= FINENSEC) || (time_phase <= -FINENSEC)) {
+               long ltemp = shift_right(time_phase, (SHIFT_SCALE - 10));
                time_phase -= ltemp << (SHIFT_SCALE - 10);
                delta_nsec += ltemp;
        }
@@ -821,6 +787,22 @@ static void update_wall_time_one_tick(void)
        }
 }
 
+/*
+ * Return how long ticks are at the moment, that is, how much time
+ * update_wall_time_one_tick will add to xtime next time we call it
+ * (assuming no calls to do_adjtimex in the meantime).
+ * The return value is in fixed-point nanoseconds with SHIFT_SCALE-10
+ * bits to the right of the binary point.
+ * This function has no side-effects.
+ */
+u64 current_tick_length(void)
+{
+       long delta_nsec;
+
+       delta_nsec = tick_nsec + adjtime_adjustment() * 1000;
+       return ((u64) delta_nsec << (SHIFT_SCALE - 10)) + time_adj;
+}
+
 /*
  * Using a loop looks inefficient, but "ticks" is
  * usually just one (we shouldn't be losing ticks,
@@ -921,6 +903,7 @@ static void run_timer_softirq(struct softirq_action *h)
 {
        tvec_base_t *base = &__get_cpu_var(tvec_bases);
 
+       hrtimer_run_queues();
        if (time_after_eq(jiffies, base->timer_jiffies))
                __run_timers(base);
 }
@@ -1137,8 +1120,8 @@ fastcall signed long __sched schedule_timeout(signed long timeout)
                if (timeout < 0)
                {
                        printk(KERN_ERR "schedule_timeout: wrong timeout "
-                              "value %lx from %p\n", timeout,
-                              __builtin_return_address(0));
+                               "value %lx from %p\n", timeout,
+                               __builtin_return_address(0));
                        current->state = TASK_RUNNING;
                        goto out;
                }
@@ -1164,15 +1147,15 @@ EXPORT_SYMBOL(schedule_timeout);
  */
 signed long __sched schedule_timeout_interruptible(signed long timeout)
 {
-       __set_current_state(TASK_INTERRUPTIBLE);
-       return schedule_timeout(timeout);
+       __set_current_state(TASK_INTERRUPTIBLE);
+       return schedule_timeout(timeout);
 }
 EXPORT_SYMBOL(schedule_timeout_interruptible);
 
 signed long __sched schedule_timeout_uninterruptible(signed long timeout)
 {
-       __set_current_state(TASK_UNINTERRUPTIBLE);
-       return schedule_timeout(timeout);
+       __set_current_state(TASK_UNINTERRUPTIBLE);
+       return schedule_timeout(timeout);
 }
 EXPORT_SYMBOL(schedule_timeout_uninterruptible);
 
@@ -1182,62 +1165,6 @@ asmlinkage long sys_gettid(void)
        return current->pid;
 }
 
-static long __sched nanosleep_restart(struct restart_block *restart)
-{
-       unsigned long expire = restart->arg0, now = jiffies;
-       struct timespec __user *rmtp = (struct timespec __user *) restart->arg1;
-       long ret;
-
-       /* Did it expire while we handled signals? */
-       if (!time_after(expire, now))
-               return 0;
-
-       expire = schedule_timeout_interruptible(expire - now);
-
-       ret = 0;
-       if (expire) {
-               struct timespec t;
-               jiffies_to_timespec(expire, &t);
-
-               ret = -ERESTART_RESTARTBLOCK;
-               if (rmtp && copy_to_user(rmtp, &t, sizeof(t)))
-                       ret = -EFAULT;
-               /* The 'restart' block is already filled in */
-       }
-       return ret;
-}
-
-asmlinkage long sys_nanosleep(struct timespec __user *rqtp, struct timespec __user *rmtp)
-{
-       struct timespec t;
-       unsigned long expire;
-       long ret;
-
-       if (copy_from_user(&t, rqtp, sizeof(t)))
-               return -EFAULT;
-
-       if ((t.tv_nsec >= 1000000000L) || (t.tv_nsec < 0) || (t.tv_sec < 0))
-               return -EINVAL;
-
-       expire = timespec_to_jiffies(&t) + (t.tv_sec || t.tv_nsec);
-       expire = schedule_timeout_interruptible(expire);
-
-       ret = 0;
-       if (expire) {
-               struct restart_block *restart;
-               jiffies_to_timespec(expire, &t);
-               if (rmtp && copy_to_user(rmtp, &t, sizeof(t)))
-                       return -EFAULT;
-
-               restart = &current_thread_info()->restart_block;
-               restart->fn = nanosleep_restart;
-               restart->arg0 = jiffies + expire;
-               restart->arg1 = (unsigned long) rmtp;
-               ret = -ERESTART_RESTARTBLOCK;
-       }
-       return ret;
-}
-
 /*
  * sys_sysinfo - fill in sysinfo struct
  */ 
@@ -1440,10 +1367,10 @@ static inline u64 time_interpolator_get_cycles(unsigned int src)
                        return x();
 
                case TIME_SOURCE_MMIO64 :
-                       return readq((void __iomem *) time_interpolator->addr);
+                       return readq_relaxed((void __iomem *)time_interpolator->addr);
 
                case TIME_SOURCE_MMIO32 :
-                       return readl((void __iomem *) time_interpolator->addr);
+                       return readl_relaxed((void __iomem *)time_interpolator->addr);
 
                default: return get_cycles();
        }
@@ -1512,16 +1439,18 @@ static void time_interpolator_update(long delta_nsec)
        if (!time_interpolator)
                return;
 
-       /* The interpolator compensates for late ticks by accumulating
-         * the late time in time_interpolator->offset. A tick earlier than
-        * expected will lead to a reset of the offset and a corresponding
-        * jump of the clock forward. Again this only works if the
-        * interpolator clock is running slightly slower than the regular clock
-        * and the tuning logic insures that.
-         */
+       /*
+        * The interpolator compensates for late ticks by accumulating the late
+        * time in time_interpolator->offset. A tick earlier than expected will
+        * lead to a reset of the offset and a corresponding jump of the clock
+        * forward. Again this only works if the interpolator clock is running
+        * slightly slower than the regular clock and the tuning logic insures
+        * that.
+        */
 
        counter = time_interpolator_get_counter(1);
-       offset = time_interpolator->offset + GET_TI_NSECS(counter, time_interpolator);
+       offset = time_interpolator->offset +
+                       GET_TI_NSECS(counter, time_interpolator);
 
        if (delta_nsec < 0 || (unsigned long) delta_nsec < offset)
                time_interpolator->offset = offset - delta_nsec;