Merge branch 'origin'

[pandora-kernel.git] / kernel / hrtimer.c

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 04ccab0..2b6e175 100644 (file)
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -21,6 +21,12 @@
  *  Credits:
  *     based on kernel/timer.c
  *
+ *     Help, testing, suggestions, bugfixes, improvements were
+ *     provided by:
+ *
+ *     George Anzinger, Andrew Morton, Steven Rostedt, Roman Zippel
+ *     et. al.
+ *
  *  For licencing details see kernel-base/COPYING
  */
 
@@ -66,6 +72,12 @@ EXPORT_SYMBOL_GPL(ktime_get_real);
 
 /*
  * The timer bases:
+ *
+ * Note: If we want to add new timer bases, we have to skip the two
+ * clock ids captured by the cpu-timers. We do this by holding empty
+ * entries rather than doing math adjustment of the clock ids.
+ * This ensures that we capture erroneous accesses to these clock ids
+ * rather than moving them into the range of valid clock id's.
  */
 
 #define MAX_HRTIMER_BASES 2
@@ -272,7 +284,7 @@ void unlock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)
  * @interval:  the interval to forward
  *
  * Forward the timer expiry so it will expire in the future.
- * The number of overruns is added to the overrun field.
+ * Returns the number of overruns.
  */
 unsigned long
 hrtimer_forward(struct hrtimer *timer, ktime_t interval)
@@ -483,29 +495,25 @@ ktime_t hrtimer_get_remaining(const struct hrtimer *timer)
 }
 
 /**
- * hrtimer_rebase - rebase an initialized hrtimer to a different base
+ * hrtimer_init - initialize a timer to the given clock
  *
- * @timer:     the timer to be rebased
+ * @timer:     the timer to be initialized
  * @clock_id:  the clock to be used
+ * @mode:      timer mode abs/rel
  */
-void hrtimer_rebase(struct hrtimer *timer, const clockid_t clock_id)
+void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
+                 enum hrtimer_mode mode)
 {
        struct hrtimer_base *bases;
 
+       memset(timer, 0, sizeof(struct hrtimer));
+
        bases = per_cpu(hrtimer_bases, raw_smp_processor_id());
-       timer->base = &bases[clock_id];
-}
 
-/**
- * hrtimer_init - initialize a timer to the given clock
- *
- * @timer:     the timer to be initialized
- * @clock_id:  the clock to be used
- */
-void hrtimer_init(struct hrtimer *timer, const clockid_t clock_id)
-{
-       memset(timer, 0, sizeof(struct hrtimer));
-       hrtimer_rebase(timer, clock_id);
+       if (clock_id == CLOCK_REALTIME && mode != HRTIMER_ABS)
+               clock_id = CLOCK_MONOTONIC;
+
+       timer->base = &bases[clock_id];
 }
 
 /**
@@ -550,6 +558,7 @@ static inline void run_hrtimer_queue(struct hrtimer_base *base)
                fn = timer->function;
                data = timer->data;
                set_curr_timer(base, timer);
+               timer->state = HRTIMER_RUNNING;
                __remove_hrtimer(timer, base);
                spin_unlock_irq(&base->lock);
 
@@ -565,6 +574,10 @@ static inline void run_hrtimer_queue(struct hrtimer_base *base)
 
                spin_lock_irq(&base->lock);
 
+               /* Another CPU has added back the timer */
+               if (timer->state != HRTIMER_RUNNING)
+                       continue;
+
                if (restart == HRTIMER_RESTART)
                        enqueue_hrtimer(timer, base);
                else
@@ -638,17 +651,17 @@ schedule_hrtimer_interruptible(struct hrtimer *timer,
        return schedule_hrtimer(timer, mode);
 }
 
-static long __sched
-nanosleep_restart(struct restart_block *restart, clockid_t clockid)
+static long __sched nanosleep_restart(struct restart_block *restart)
 {
-       struct timespec __user *rmtp, tu;
+       struct timespec __user *rmtp;
+       struct timespec tu;
        void *rfn_save = restart->fn;
        struct hrtimer timer;
        ktime_t rem;
 
        restart->fn = do_no_restart_syscall;
 
-       hrtimer_init(&timer, clockid);
+       hrtimer_init(&timer, (clockid_t) restart->arg3, HRTIMER_ABS);
 
        timer.expires.tv64 = ((u64)restart->arg1 << 32) | (u64) restart->arg0;
 
@@ -668,16 +681,6 @@ nanosleep_restart(struct restart_block *restart, clockid_t clockid)
        return -ERESTART_RESTARTBLOCK;
 }
 
-static long __sched nanosleep_restart_mono(struct restart_block *restart)
-{
-       return nanosleep_restart(restart, CLOCK_MONOTONIC);
-}
-
-static long __sched nanosleep_restart_real(struct restart_block *restart)
-{
-       return nanosleep_restart(restart, CLOCK_REALTIME);
-}
-
 long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
                       const enum hrtimer_mode mode, const clockid_t clockid)
 {
@@ -686,7 +689,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
        struct timespec tu;
        ktime_t rem;
 
-       hrtimer_init(&timer, clockid);
+       hrtimer_init(&timer, clockid, mode);
 
        timer.expires = timespec_to_ktime(*rqtp);
 
@@ -694,7 +697,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
        if (rem.tv64 <= 0)
                return 0;
 
-       /* Absolute timers do not update the rmtp value: */
+       /* Absolute timers do not update the rmtp value and restart: */
        if (mode == HRTIMER_ABS)
                return -ERESTARTNOHAND;
 
@@ -704,11 +707,11 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
                return -EFAULT;
 
        restart = &current_thread_info()->restart_block;
-       restart->fn = (clockid == CLOCK_MONOTONIC) ?
-               nanosleep_restart_mono : nanosleep_restart_real;
+       restart->fn = nanosleep_restart;
        restart->arg0 = timer.expires.tv64 & 0xFFFFFFFF;
        restart->arg1 = timer.expires.tv64 >> 32;
        restart->arg2 = (unsigned long) rmtp;
+       restart->arg3 = (unsigned long) timer.base->index;
 
        return -ERESTART_RESTARTBLOCK;
 }
@@ -735,10 +738,8 @@ static void __devinit init_hrtimers_cpu(int cpu)
        struct hrtimer_base *base = per_cpu(hrtimer_bases, cpu);
        int i;
 
-       for (i = 0; i < MAX_HRTIMER_BASES; i++) {
+       for (i = 0; i < MAX_HRTIMER_BASES; i++, base++)
                spin_lock_init(&base->lock);
-               base++;
-       }
 }
 
 #ifdef CONFIG_HOTPLUG_CPU