3 files changed, 34 insertions, 64 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 4ae8cfc1c89c..7f0ab5ee948c 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -802,7 +802,7 @@ static inline int copy_signal(unsigned long clone_flags, struct task_struct * ts
         init_sigpending(&sig->shared_pending);
         INIT_LIST_HEAD(&sig->posix_timers);
 
-        hrtimer_init(&sig->real_timer, CLOCK_MONOTONIC);
+        hrtimer_init(&sig->real_timer, CLOCK_MONOTONIC, HRTIMER_REL);
         sig->it_real_incr.tv64 = 0;
         sig->real_timer.function = it_real_fn;
         sig->real_timer.data = tsk;
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index f580dd9db286..efff9496b2fa 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -66,6 +66,12 @@ 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
@@ -483,29 +489,25 @@ 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];
 }
 
 /**
@@ -643,8 +645,7 @@ 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;
         struct timespec tu;
@@ -654,7 +655,7 @@ nanosleep_restart(struct restart_block *restart, clockid_t clockid)
 
         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;
 
@@ -674,16 +675,6 @@ 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)
 {
@@ -692,7 +683,7 @@ 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);
 
@@ -700,7 +691,7 @@ 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;
 
@@ -710,11 +701,11 @@ 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;
 }
@@ -741,10 +732,8 @@ 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
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index 3b606d361b52..28e72fd0029f 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -194,9 +194,7 @@ static inline int common_clock_set(const clockid_t which_clock,
 
 static int common_timer_create(struct k_itimer *new_timer)
 {
-        hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock);
-        new_timer->it.real.timer.data = new_timer;
-        new_timer->it.real.timer.function = posix_timer_fn;
+        hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock, 0);
         return 0;
 }
 
@@ -693,6 +691,7 @@ common_timer_set(struct k_itimer *timr, int flags,
                  struct itimerspec *new_setting, struct itimerspec *old_setting)
 {
         struct hrtimer *timer = &timr->it.real.timer;
+        enum hrtimer_mode mode;
 
         if (old_setting)
                 common_timer_get(timr, old_setting);
@@ -714,14 +713,10 @@ common_timer_set(struct k_itimer *timr, int flags,
         if (!new_setting->it_value.tv_sec && !new_setting->it_value.tv_nsec)
                 return 0;
 
-        /* Posix madness. Only absolute CLOCK_REALTIME timers
-         * are affected by clock sets. So we must reiniatilize
-         * the timer.
-         */
-        if (timr->it_clock == CLOCK_REALTIME && (flags & TIMER_ABSTIME))
-                hrtimer_rebase(timer, CLOCK_REALTIME);
-        else
-                hrtimer_rebase(timer, CLOCK_MONOTONIC);
+        mode = flags & TIMER_ABSTIME ? HRTIMER_ABS : HRTIMER_REL;
+        hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
+        timr->it.real.timer.data = timr;
+        timr->it.real.timer.function = posix_timer_fn;
 
         timer->expires = timespec_to_ktime(new_setting->it_value);
 
@@ -732,8 +727,7 @@ common_timer_set(struct k_itimer *timr, int flags,
         if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE))
                 return 0;
 
-        hrtimer_start(timer, timer->expires, (flags & TIMER_ABSTIME) ?
-                      HRTIMER_ABS : HRTIMER_REL);
+        hrtimer_start(timer, timer->expires, mode);
         return 0;
 }
 
@@ -948,21 +942,8 @@ sys_clock_getres(const clockid_t which_clock, struct timespec __user *tp)
 static int common_nsleep(const clockid_t which_clock, int flags,
                          struct timespec *tsave, struct timespec __user *rmtp)
 {
-        int mode = flags & TIMER_ABSTIME ? HRTIMER_ABS : HRTIMER_REL;
-        int clockid = which_clock;
-
-        switch (which_clock) {
-        case CLOCK_REALTIME:
-                /* Posix madness. Only absolute timers on clock realtime
-                   are affected by clock set. */
-                if (mode != HRTIMER_ABS)
-                        clockid = CLOCK_MONOTONIC;
-        case CLOCK_MONOTONIC:
-                break;
-        default:
-                return -EINVAL;
-        }
-        return hrtimer_nanosleep(tsave, rmtp, mode, clockid);
+        return hrtimer_nanosleep(tsave, rmtp, flags & TIMER_ABSTIME ?
+                                 HRTIMER_ABS : HRTIMER_REL, which_clock);
 }
 
 asmlinkage long