hrtimers: Convert hrtimers to use timerlist infrastructure

Converts the hrtimer code to use the new timerlist infrastructure

Signed-off-by: John Stultz <john.stultz@linaro.org>
LKML Reference: <1290136329-18291-3-git-send-email-john.stultz@linaro.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Richard Cochran <richardcochran@gmail.com>

2 files changed, 34 insertions, 60 deletions

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index ce669174f355..93976ad42f5a 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -516,10 +516,13 @@ hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal)
 
         for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) {
                 struct hrtimer *timer;
+                struct timerqueue_node *next;
 
-                if (!base->first)
+                next = timerqueue_getnext(&base->active);
+                if (!next)
                         continue;
-                timer = rb_entry(base->first, struct hrtimer, node);
+                timer = container_of(next, struct hrtimer, node);
+
                 expires = ktime_sub(hrtimer_get_expires(timer), base->offset);
                 /*
                  * clock_was_set() has changed base->offset so the
@@ -840,48 +843,17 @@ EXPORT_SYMBOL_GPL(hrtimer_forward);
 static int enqueue_hrtimer(struct hrtimer *timer,
                            struct hrtimer_clock_base *base)
 {
-        struct rb_node **link = &base->active.rb_node;
-        struct rb_node *parent = NULL;
-        struct hrtimer *entry;
-        int leftmost = 1;
-
         debug_activate(timer);
 
-        /*
-         * Find the right place in the rbtree:
-         */
-        while (*link) {
-                parent = *link;
-                entry = rb_entry(parent, struct hrtimer, node);
-                /*
-                 * We dont care about collisions. Nodes with
-                 * the same expiry time stay together.
-                 */
-                if (hrtimer_get_expires_tv64(timer) <
-                                hrtimer_get_expires_tv64(entry)) {
-                        link = &(*link)->rb_left;
-                } else {
-                        link = &(*link)->rb_right;
-                        leftmost = 0;
-                }
-        }
+        timerqueue_add(&base->active, &timer->node);
 
         /*
-         * Insert the timer to the rbtree and check whether it
-         * replaces the first pending timer
-         */
-        if (leftmost)
-                base->first = &timer->node;
-
-        rb_link_node(&timer->node, parent, link);
-        rb_insert_color(&timer->node, &base->active);
-        /*
          * HRTIMER_STATE_ENQUEUED is or'ed to the current state to preserve the
          * state of a possibly running callback.
          */
         timer->state |= HRTIMER_STATE_ENQUEUED;
 
-        return leftmost;
+        return (&timer->node == base->active.next);
 }
 
 /*
@@ -901,12 +873,7 @@ static void __remove_hrtimer(struct hrtimer *timer,
         if (!(timer->state & HRTIMER_STATE_ENQUEUED))
                 goto out;
 
-        /*
-         * Remove the timer from the rbtree and replace the first
-         * entry pointer if necessary.
-         */
-        if (base->first == &timer->node) {
-                base->first = rb_next(&timer->node);
+        if (&timer->node == timerqueue_getnext(&base->active)) {
 #ifdef CONFIG_HIGH_RES_TIMERS
                 /* Reprogram the clock event device. if enabled */
                 if (reprogram && hrtimer_hres_active()) {
@@ -919,7 +886,7 @@ static void __remove_hrtimer(struct hrtimer *timer,
                 }
 #endif
         }
-        rb_erase(&timer->node, &base->active);
+        timerqueue_del(&base->active, &timer->node);
 out:
         timer->state = newstate;
 }
@@ -1123,11 +1090,13 @@ ktime_t hrtimer_get_next_event(void)
         if (!hrtimer_hres_active()) {
                 for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) {
                         struct hrtimer *timer;
+                        struct timerqueue_node *next;
 
-                        if (!base->first)
+                        next = timerqueue_getnext(&base->active);
+                        if (!next)
                                 continue;
 
-                        timer = rb_entry(base->first, struct hrtimer, node);
+                        timer = container_of(next, struct hrtimer, node);
                         delta.tv64 = hrtimer_get_expires_tv64(timer);
                         delta = ktime_sub(delta, base->get_time());
                         if (delta.tv64 < mindelta.tv64)
@@ -1157,6 +1126,7 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 
         timer->base = &cpu_base->clock_base[clock_id];
         hrtimer_init_timer_hres(timer);
+        timerqueue_init(&timer->node);
 
 #ifdef CONFIG_TIMER_STATS
         timer->start_site = NULL;
@@ -1270,14 +1240,14 @@ retry:
 
         for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
                 ktime_t basenow;
-                struct rb_node *node;
+                struct timerqueue_node *node;
 
                 basenow = ktime_add(now, base->offset);
 
-                while ((node = base->first)) {
+                while ((node = timerqueue_getnext(&base->active))) {
                         struct hrtimer *timer;
 
-                        timer = rb_entry(node, struct hrtimer, node);
+                        timer = container_of(node, struct hrtimer, node);
 
                         /*
                          * The immediate goal for using the softexpires is
@@ -1433,7 +1403,7 @@ void hrtimer_run_pending(void)
  */
 void hrtimer_run_queues(void)
 {
-        struct rb_node *node;
+        struct timerqueue_node *node;
         struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
         struct hrtimer_clock_base *base;
         int index, gettime = 1;
@@ -1442,9 +1412,11 @@ void hrtimer_run_queues(void)
                 return;
 
         for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) {
-                base = &cpu_base->clock_base[index];
+                struct timerqueue_node *next;
 
-                if (!base->first)
+                base = &cpu_base->clock_base[index];
+                next = timerqueue_getnext(&base->active);
+                if (!next)
                         continue;
 
                 if (gettime) {
@@ -1454,10 +1426,10 @@ void hrtimer_run_queues(void)
 
                 raw_spin_lock(&cpu_base->lock);
 
-                while ((node = base->first)) {
+                while ((node = next)) {
                         struct hrtimer *timer;
 
-                        timer = rb_entry(node, struct hrtimer, node);
+                        timer = container_of(node, struct hrtimer, node);
                         if (base->softirq_time.tv64 <=
                                         hrtimer_get_expires_tv64(timer))
                                 break;
@@ -1622,8 +1594,10 @@ static void __cpuinit init_hrtimers_cpu(int cpu)
 
         raw_spin_lock_init(&cpu_base->lock);
 
-        for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++)
+        for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
                 cpu_base->clock_base[i].cpu_base = cpu_base;
+                timerqueue_init_head(&cpu_base->clock_base[i].active);
+        }
 
         hrtimer_init_hres(cpu_base);
 }
@@ -1634,10 +1608,10 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
                                 struct hrtimer_clock_base *new_base)
 {
         struct hrtimer *timer;
-        struct rb_node *node;
+        struct timerqueue_node *node;
 
-        while ((node = rb_first(&old_base->active))) {
-                timer = rb_entry(node, struct hrtimer, node);
+        while ((node = timerqueue_getnext(&old_base->active))) {
+                timer = container_of(node, struct hrtimer, node);
                 BUG_ON(hrtimer_callback_running(timer));
                 debug_deactivate(timer);
 
diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
index ab8f5e33fa92..32a19f9397fc 100644
--- a/kernel/time/timer_list.c
+++ b/kernel/time/timer_list.c
@@ -79,26 +79,26 @@ print_active_timers(struct seq_file *m, struct hrtimer_clock_base *base,
 {
         struct hrtimer *timer, tmp;
         unsigned long next = 0, i;
-        struct rb_node *curr;
+        struct timerqueue_node *curr;
         unsigned long flags;
 
 next_one:
         i = 0;
         raw_spin_lock_irqsave(&base->cpu_base->lock, flags);
 
-        curr = base->first;
+        curr = timerqueue_getnext(&base->active);
         /*
          * Crude but we have to do this O(N*N) thing, because
          * we have to unlock the base when printing:
          */
         while (curr && i < next) {
-                curr = rb_next(curr);
+                curr = timerqueue_iterate_next(curr);
                 i++;
         }
 
         if (curr) {
 
-                timer = rb_entry(curr, struct hrtimer, node);
+                timer = container_of(curr, struct hrtimer, node);
                 tmp = *timer;
                 raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags);