2.6.26-rc1

 kernel

diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 0a6d2e5..c2730a5 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -62,7 +62,12 @@ static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
    if (!rt_rq->tg)
       return RUNTIME_INF;
 
-   return rt_rq->tg->rt_runtime;
+   return rt_rq->rt_runtime;
+}
+
+static inline u64 sched_rt_period(struct rt_rq *rt_rq)
+{
+   return ktime_to_ns(rt_rq->tg->rt_bandwidth.rt_period);
 }
 
 #define for_each_leaf_rt_rq(rt_rq, rq) \
@@ -127,14 +132,39 @@ static int rt_se_boosted(struct sched_rt_entity *rt_se)
    return p->prio != p->normal_prio;
 }
 
+#ifdef CONFIG_SMP
+static inline cpumask_t sched_rt_period_mask(void)
+{
+   return cpu_rq(smp_processor_id())->rd->span;
+}
+#else
+static inline cpumask_t sched_rt_period_mask(void)
+{
+   return cpu_online_map;
+}
+#endif
+
+static inline
+struct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu)
+{
+   return container_of(rt_b, struct task_group, rt_bandwidth)->rt_rq[cpu];
+}
+
+static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
+{
+   return &rt_rq->tg->rt_bandwidth;
+}
+
 #else
 
 static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
 {
-   if (sysctl_sched_rt_runtime == -1)
-      return RUNTIME_INF;
+   return rt_rq->rt_runtime;
+}
 
-   return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
+static inline u64 sched_rt_period(struct rt_rq *rt_rq)
+{
+   return ktime_to_ns(def_rt_bandwidth.rt_period);
 }
 
 #define for_each_leaf_rt_rq(rt_rq, rq) \
@@ -173,6 +203,102 @@ static inline int rt_rq_throttled(struct rt_rq *rt_rq)
 {
    return rt_rq->rt_throttled;
 }
+
+static inline cpumask_t sched_rt_period_mask(void)
+{
+   return cpu_online_map;
+}
+
+static inline
+struct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu)
+{
+   return &cpu_rq(cpu)->rt;
+}
+
+static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
+{
+   return &def_rt_bandwidth;
+}
+
+#endif
+
+static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
+{
+   int i, idle = 1;
+   cpumask_t span;
+
+   if (rt_b->rt_runtime == RUNTIME_INF)
+      return 1;
+
+   span = sched_rt_period_mask();
+   for_each_cpu_mask(i, span) {
+      int enqueue = 0;
+      struct rt_rq *rt_rq = sched_rt_period_rt_rq(rt_b, i);
+      struct rq *rq = rq_of_rt_rq(rt_rq);
+
+      spin_lock(&rq->lock);
+      if (rt_rq->rt_time) {
+         u64 runtime;
+
+         spin_lock(&rt_rq->rt_runtime_lock);
+         runtime = rt_rq->rt_runtime;
+         rt_rq->rt_time -= min(rt_rq->rt_time, overrun*runtime);
+         if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
+            rt_rq->rt_throttled = 0;
+            enqueue = 1;
+         }
+         if (rt_rq->rt_time || rt_rq->rt_nr_running)
+            idle = 0;
+         spin_unlock(&rt_rq->rt_runtime_lock);
+      }
+
+      if (enqueue)
+         sched_rt_rq_enqueue(rt_rq);
+      spin_unlock(&rq->lock);
+   }
+
+   return idle;
+}
+
+#ifdef CONFIG_SMP
+static int balance_runtime(struct rt_rq *rt_rq)
+{
+   struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
+   struct root_domain *rd = cpu_rq(smp_processor_id())->rd;
+   int i, weight, more = 0;
+   u64 rt_period;
+
+   weight = cpus_weight(rd->span);
+
+   spin_lock(&rt_b->rt_runtime_lock);
+   rt_period = ktime_to_ns(rt_b->rt_period);
+   for_each_cpu_mask(i, rd->span) {
+      struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i);
+      s64 diff;
+
+      if (iter == rt_rq)
+         continue;
+
+      spin_lock(&iter->rt_runtime_lock);
+      diff = iter->rt_runtime - iter->rt_time;
+      if (diff > 0) {
+         do_div(diff, weight);
+         if (rt_rq->rt_runtime + diff > rt_period)
+            diff = rt_period - rt_rq->rt_runtime;
+         iter->rt_runtime -= diff;
+         rt_rq->rt_runtime += diff;
+         more = 1;
+         if (rt_rq->rt_runtime == rt_period) {
+            spin_unlock(&iter->rt_runtime_lock);
+            break;
+         }
+      }
+      spin_unlock(&iter->rt_runtime_lock);
+   }
+   spin_unlock(&rt_b->rt_runtime_lock);
+
+   return more;
+}
 #endif
 
 static inline int rt_se_prio(struct sched_rt_entity *rt_se)
@@ -197,12 +323,24 @@ static int sched_rt_runtime_exceeded(struct rt_rq *rt_rq)
    if (rt_rq->rt_throttled)
       return rt_rq_throttled(rt_rq);
 
+   if (sched_rt_runtime(rt_rq) >= sched_rt_period(rt_rq))
+      return 0;
+
+#ifdef CONFIG_SMP
    if (rt_rq->rt_time > runtime) {
-      struct rq *rq = rq_of_rt_rq(rt_rq);
+      int more;
 
-      rq->rt_throttled = 1;
-      rt_rq->rt_throttled = 1;
+      spin_unlock(&rt_rq->rt_runtime_lock);
+      more = balance_runtime(rt_rq);
+      spin_lock(&rt_rq->rt_runtime_lock);
 
+      if (more)
+         runtime = sched_rt_runtime(rt_rq);
+   }
+#endif
+
+   if (rt_rq->rt_time > runtime) {
+      rt_rq->rt_throttled = 1;
       if (rt_rq_throttled(rt_rq)) {
          sched_rt_rq_dequeue(rt_rq);
          return 1;
@@ -212,29 +350,6 @@ static int sched_rt_runtime_exceeded(struct rt_rq *rt_rq)
    return 0;
 }
 
-static void update_sched_rt_period(struct rq *rq)
-{
-   struct rt_rq *rt_rq;
-   u64 period;
-
-   while (rq->clock > rq->rt_period_expire) {
-      period = (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
-      rq->rt_period_expire += period;
-
-      for_each_leaf_rt_rq(rt_rq, rq) {
-         u64 runtime = sched_rt_runtime(rt_rq);
-
-         rt_rq->rt_time -= min(rt_rq->rt_time, runtime);
-         if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
-            rt_rq->rt_throttled = 0;
-            sched_rt_rq_enqueue(rt_rq);
-         }
-      }
-
-      rq->rt_throttled = 0;
-   }
-}
-
 /*
  * Update the current task's runtime statistics. Skip current tasks that
  * are not in our scheduling class.
@@ -259,9 +374,15 @@ static void update_curr_rt(struct rq *rq)
    curr->se.exec_start = rq->clock;
    cpuacct_charge(curr, delta_exec);
 
-   rt_rq->rt_time += delta_exec;
-   if (sched_rt_runtime_exceeded(rt_rq))
-      resched_task(curr);
+   for_each_sched_rt_entity(rt_se) {
+      rt_rq = rt_rq_of_se(rt_se);
+
+      spin_lock(&rt_rq->rt_runtime_lock);
+      rt_rq->rt_time += delta_exec;
+      if (sched_rt_runtime_exceeded(rt_rq))
+         resched_task(curr);
+      spin_unlock(&rt_rq->rt_runtime_lock);
+   }
 }
 
 static inline
@@ -284,6 +405,11 @@ void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
 #ifdef CONFIG_RT_GROUP_SCHED
    if (rt_se_boosted(rt_se))
       rt_rq->rt_nr_boosted++;
+
+   if (rt_rq->tg)
+      start_rt_bandwidth(&rt_rq->tg->rt_bandwidth);
+#else
+   start_rt_bandwidth(&def_rt_bandwidth);
 #endif
 }
 
@@ -353,27 +479,21 @@ static void dequeue_rt_entity(struct sched_rt_entity *rt_se)
 /*
  * Because the prio of an upper entry depends on the lower
  * entries, we must remove entries top - down.
- *
- * XXX: O(1/2 h^2) because we can only walk up, not down the chain.
- *      doesn't matter much for now, as h=2 for GROUP_SCHED.
  */
 static void dequeue_rt_stack(struct task_struct *p)
 {
-   struct sched_rt_entity *rt_se, *top_se;
+   struct sched_rt_entity *rt_se, *back = NULL;
 
-   /*
-    * dequeue all, top - down.
-    */
-   do {
-      rt_se = &p->rt;
-      top_se = NULL;
-      for_each_sched_rt_entity(rt_se) {
-         if (on_rt_rq(rt_se))
-            top_se = rt_se;
-      }
-      if (top_se)
-         dequeue_rt_entity(top_se);
-   } while (top_se);
+   rt_se = &p->rt;
+   for_each_sched_rt_entity(rt_se) {
+      rt_se->back = back;
+      back = rt_se;
+   }
+
+   for (rt_se = back; rt_se; rt_se = rt_se->back) {
+      if (on_rt_rq(rt_se))
+         dequeue_rt_entity(rt_se);
+   }
 }
 
 /*
@@ -393,6 +513,8 @@ static void enqueue_task_rt(struct rq *rq, struct task_struct *p, int wakeup)
     */
    for_each_sched_rt_entity(rt_se)
       enqueue_rt_entity(rt_se);
+
+   inc_cpu_load(rq, p->se.load.weight);
 }
 
 static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
@@ -412,6 +534,8 @@ static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
       if (rt_rq && rt_rq->rt_nr_running)
          enqueue_rt_entity(rt_se);
    }
+
+   dec_cpu_load(rq, p->se.load.weight);
 }
 
 /*
@@ -1001,7 +1125,8 @@ move_one_task_rt(struct rq *this_rq, int this_cpu, struct rq *busiest,
    return 0;
 }
 
-static void set_cpus_allowed_rt(struct task_struct *p, cpumask_t *new_mask)
+static void set_cpus_allowed_rt(struct task_struct *p,
+            const cpumask_t *new_mask)
 {
    int weight = cpus_weight(*new_mask);