2.6.25-rc7

 kernel

diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index da7c061..86a9337 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -20,6 +20,8 @@
  *  Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
  */
 
+#include <linux/latencytop.h>
+
 /*
  * Targeted preemption latency for CPU-bound tasks:
  * (default: 20ms * (1 + ilog(ncpus)), units: nanoseconds)
@@ -71,13 +73,13 @@ unsigned int sysctl_sched_batch_wakeup_granularity = 10000000UL;
 
 /*
  * SCHED_OTHER wake-up granularity.
- * (default: 10 msec * (1 + ilog(ncpus)), units: nanoseconds)
+ * (default: 5 msec * (1 + ilog(ncpus)), units: nanoseconds)
  *
  * This option delays the preemption effects of decoupled workloads
  * and reduces their over-scheduling. Synchronous workloads will still
  * have immediate wakeup/sleep latencies.
  */
-unsigned int sysctl_sched_wakeup_granularity = 10000000UL;
+unsigned int sysctl_sched_wakeup_granularity = 5000000UL;
 
 const_debug unsigned int sysctl_sched_migration_cost = 500000UL;
 
@@ -173,8 +175,15 @@ static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
     * Maintain a cache of leftmost tree entries (it is frequently
     * used):
     */
-   if (leftmost)
+   if (leftmost) {
       cfs_rq->rb_leftmost = &se->run_node;
+      /*
+       * maintain cfs_rq->min_vruntime to be a monotonic increasing
+       * value tracking the leftmost vruntime in the tree.
+       */
+      cfs_rq->min_vruntime =
+         max_vruntime(cfs_rq->min_vruntime, se->vruntime);
+   }
 
    rb_link_node(&se->run_node, parent, link);
    rb_insert_color(&se->run_node, &cfs_rq->tasks_timeline);
@@ -182,8 +191,24 @@ static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
 
 static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
-   if (cfs_rq->rb_leftmost == &se->run_node)
-      cfs_rq->rb_leftmost = rb_next(&se->run_node);
+   if (cfs_rq->rb_leftmost == &se->run_node) {
+      struct rb_node *next_node;
+      struct sched_entity *next;
+
+      next_node = rb_next(&se->run_node);
+      cfs_rq->rb_leftmost = next_node;
+
+      if (next_node) {
+         next = rb_entry(next_node,
+               struct sched_entity, run_node);
+         cfs_rq->min_vruntime =
+            max_vruntime(cfs_rq->min_vruntime,
+                    next->vruntime);
+      }
+   }
+
+   if (cfs_rq->next == se)
+      cfs_rq->next = NULL;
 
    rb_erase(&se->run_node, &cfs_rq->tasks_timeline);
 }
@@ -200,17 +225,12 @@ static struct sched_entity *__pick_next_entity(struct cfs_rq *cfs_rq)
 
 static inline struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq)
 {
-   struct rb_node **link = &cfs_rq->tasks_timeline.rb_node;
-   struct sched_entity *se = NULL;
-   struct rb_node *parent;
+   struct rb_node *last = rb_last(&cfs_rq->tasks_timeline);
 
-   while (*link) {
-      parent = *link;
-      se = rb_entry(parent, struct sched_entity, run_node);
-      link = &parent->rb_right;
-   }
+   if (!last)
+      return NULL;
 
-   return se;
+   return rb_entry(last, struct sched_entity, run_node);
 }
 
 /**************************************************************
@@ -248,8 +268,8 @@ static u64 __sched_period(unsigned long nr_running)
    unsigned long nr_latency = sched_nr_latency;
 
    if (unlikely(nr_running > nr_latency)) {
+      period = sysctl_sched_min_granularity;
       period *= nr_running;
-      do_div(period, nr_latency);
    }
 
    return period;
@@ -263,12 +283,8 @@ static u64 __sched_period(unsigned long nr_running)
  */
 static u64 sched_slice(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
-   u64 slice = __sched_period(cfs_rq->nr_running);
-
-   slice *= se->load.weight;
-   do_div(slice, cfs_rq->load.weight);
-
-   return slice;
+   return calc_delta_mine(__sched_period(cfs_rq->nr_running),
+                se->load.weight, &cfs_rq->load);
 }
 
 /*
@@ -286,11 +302,6 @@ static u64 __sched_vslice(unsigned long rq_weight, unsigned long nr_running)
    return vslice;
 }
 
-static u64 sched_vslice(struct cfs_rq *cfs_rq)
-{
-   return __sched_vslice(cfs_rq->load.weight, cfs_rq->nr_running);
-}
-
 static u64 sched_vslice_add(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
    return __sched_vslice(cfs_rq->load.weight + se->load.weight,
@@ -306,7 +317,6 @@ __update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr,
          unsigned long delta_exec)
 {
    unsigned long delta_exec_weighted;
-   u64 vruntime;
 
    schedstat_set(curr->exec_max, max((u64)delta_exec, curr->exec_max));
 
@@ -318,19 +328,6 @@ __update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr,
                      &curr->load);
    }
    curr->vruntime += delta_exec_weighted;
-
-   /*
-    * maintain cfs_rq->min_vruntime to be a monotonic increasing
-    * value tracking the leftmost vruntime in the tree.
-    */
-   if (first_fair(cfs_rq)) {
-      vruntime = min_vruntime(curr->vruntime,
-            __pick_next_entity(cfs_rq)->vruntime);
-   } else
-      vruntime = curr->vruntime;
-
-   cfs_rq->min_vruntime =
-      max_vruntime(cfs_rq->min_vruntime, vruntime);
 }
 
 static void update_curr(struct cfs_rq *cfs_rq)
@@ -383,6 +380,9 @@ update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
    schedstat_set(se->wait_max, max(se->wait_max,
          rq_of(cfs_rq)->clock - se->wait_start));
+   schedstat_set(se->wait_count, se->wait_count + 1);
+   schedstat_set(se->wait_sum, se->wait_sum +
+         rq_of(cfs_rq)->clock - se->wait_start);
    schedstat_set(se->wait_start, 0);
 }
 
@@ -434,6 +434,7 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
 #ifdef CONFIG_SCHEDSTATS
    if (se->sleep_start) {
       u64 delta = rq_of(cfs_rq)->clock - se->sleep_start;
+      struct task_struct *tsk = task_of(se);
 
       if ((s64)delta < 0)
          delta = 0;
@@ -443,9 +444,12 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
 
       se->sleep_start = 0;
       se->sum_sleep_runtime += delta;
+
+      account_scheduler_latency(tsk, delta >> 10, 1);
    }
    if (se->block_start) {
       u64 delta = rq_of(cfs_rq)->clock - se->block_start;
+      struct task_struct *tsk = task_of(se);
 
       if ((s64)delta < 0)
          delta = 0;
@@ -462,11 +466,11 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
        * time that the task spent sleeping:
        */
       if (unlikely(prof_on == SLEEP_PROFILING)) {
-         struct task_struct *tsk = task_of(se);
 
          profile_hits(SLEEP_PROFILING, (void *)get_wchan(tsk),
                  delta >> 20);
       }
+      account_scheduler_latency(tsk, delta >> 10, 0);
    }
 #endif
 }
@@ -489,16 +493,11 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
 {
    u64 vruntime;
 
-   vruntime = cfs_rq->min_vruntime;
-
-   if (sched_feat(TREE_AVG)) {
-      struct sched_entity *last = __pick_last_entity(cfs_rq);
-      if (last) {
-         vruntime += last->vruntime;
-         vruntime >>= 1;
-      }
-   } else if (sched_feat(APPROX_AVG) && cfs_rq->nr_running)
-      vruntime += sched_vslice(cfs_rq)/2;
+   if (first_fair(cfs_rq)) {
+      vruntime = min_vruntime(cfs_rq->min_vruntime,
+            __pick_next_entity(cfs_rq)->vruntime);
+   } else
+      vruntime = cfs_rq->min_vruntime;
 
    /*
     * The 'current' period is already promised to the current tasks,
@@ -511,8 +510,10 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
 
    if (!initial) {
       /* sleeps upto a single latency don't count. */
-      if (sched_feat(NEW_FAIR_SLEEPERS) && entity_is_task(se))
-         vruntime -= sysctl_sched_latency;
+      if (sched_feat(NEW_FAIR_SLEEPERS)) {
+         vruntime -= calc_delta_fair(sysctl_sched_latency,
+                      &cfs_rq->load);
+      }
 
       /* ensure we never gain time by being placed backwards. */
       vruntime = max_vruntime(se->vruntime, vruntime);
@@ -541,6 +542,21 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int wakeup)
    account_entity_enqueue(cfs_rq, se);
 }
 
+static void update_avg(u64 *avg, u64 sample)
+{
+   s64 diff = sample - *avg;
+   *avg += diff >> 3;
+}
+
+static void update_avg_stats(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+   if (!se->last_wakeup)
+      return;
+
+   update_avg(&se->avg_overlap, se->sum_exec_runtime - se->last_wakeup);
+   se->last_wakeup = 0;
+}
+
 static void
 dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
 {
@@ -551,6 +567,7 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
 
    update_stats_dequeue(cfs_rq, se);
    if (sleep) {
+      update_avg_stats(cfs_rq, se);
 #ifdef CONFIG_SCHEDSTATS
       if (entity_is_task(se)) {
          struct task_struct *tsk = task_of(se);
@@ -612,12 +629,32 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
    se->prev_sum_exec_runtime = se->sum_exec_runtime;
 }
 
+static struct sched_entity *
+pick_next(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+   s64 diff, gran;
+
+   if (!cfs_rq->next)
+      return se;
+
+   diff = cfs_rq->next->vruntime - se->vruntime;
+   if (diff < 0)
+      return se;
+
+   gran = calc_delta_fair(sysctl_sched_wakeup_granularity, &cfs_rq->load);
+   if (diff > gran)
+      return se;
+
+   return cfs_rq->next;
+}
+
 static struct sched_entity *pick_next_entity(struct cfs_rq *cfs_rq)
 {
    struct sched_entity *se = NULL;
 
    if (first_fair(cfs_rq)) {
       se = __pick_next_entity(cfs_rq);
+      se = pick_next(cfs_rq, se);
       set_next_entity(cfs_rq, se);
    }
 
@@ -642,13 +679,29 @@ static void put_prev_entity(struct cfs_rq *cfs_rq, struct sched_entity *prev)
    cfs_rq->curr = NULL;
 }
 
-static void entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
+static void
+entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
 {
    /*
     * Update run-time statistics of the 'current'.
     */
    update_curr(cfs_rq);
 
+#ifdef CONFIG_SCHED_HRTICK
+   /*
+    * queued ticks are scheduled to match the slice, so don't bother
+    * validating it and just reschedule.
+    */
+   if (queued)
+      return resched_task(rq_of(cfs_rq)->curr);
+   /*
+    * don't let the period tick interfere with the hrtick preemption
+    */
+   if (!sched_feat(DOUBLE_TICK) &&
+         hrtimer_active(&rq_of(cfs_rq)->hrtick_timer))
+      return;
+#endif
+
    if (cfs_rq->nr_running > 1 || !sched_feat(WAKEUP_PREEMPT))
       check_preempt_tick(cfs_rq, curr);
 }
@@ -690,7 +743,7 @@ static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu)
 
 /* Iterate thr' all leaf cfs_rq's on a runqueue */
 #define for_each_leaf_cfs_rq(rq, cfs_rq) \
-   list_for_each_entry(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list)
+   list_for_each_entry_rcu(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list)
 
 /* Do the two (enqueued) entities belong to the same group ? */
 static inline int
@@ -752,6 +805,43 @@ static inline struct sched_entity *parent_entity(struct sched_entity *se)
 
 #endif   /* CONFIG_FAIR_GROUP_SCHED */
 
+#ifdef CONFIG_SCHED_HRTICK
+static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
+{
+   int requeue = rq->curr == p;
+   struct sched_entity *se = &p->se;
+   struct cfs_rq *cfs_rq = cfs_rq_of(se);
+
+   WARN_ON(task_rq(p) != rq);
+
+   if (hrtick_enabled(rq) && cfs_rq->nr_running > 1) {
+      u64 slice = sched_slice(cfs_rq, se);
+      u64 ran = se->sum_exec_runtime - se->prev_sum_exec_runtime;
+      s64 delta = slice - ran;
+
+      if (delta < 0) {
+         if (rq->curr == p)
+            resched_task(p);
+         return;
+      }
+
+      /*
+       * Don't schedule slices shorter than 10000ns, that just
+       * doesn't make sense. Rely on vruntime for fairness.
+       */
+      if (!requeue)
+         delta = max(10000LL, delta);
+
+      hrtick_start(rq, delta, requeue);
+   }
+}
+#else
+static inline void
+hrtick_start_fair(struct rq *rq, struct task_struct *p)
+{
+}
+#endif
+
 /*
  * The enqueue_task method is called before nr_running is
  * increased. Here we update the fair scheduling stats and
@@ -769,6 +859,8 @@ static void enqueue_task_fair(struct rq *rq, struct task_struct *p, int wakeup)
       enqueue_entity(cfs_rq, se, wakeup);
       wakeup = 1;
    }
+
+   hrtick_start_fair(rq, rq->curr);
 }
 
 /*
@@ -789,6 +881,8 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int sleep)
          break;
       sleep = 1;
    }
+
+   hrtick_start_fair(rq, rq->curr);
 }
 
 /*
@@ -836,6 +930,179 @@ static void yield_task_fair(struct rq *rq)
 }
 
 /*
+ * wake_idle() will wake a task on an idle cpu if task->cpu is
+ * not idle and an idle cpu is available.  The span of cpus to
+ * search starts with cpus closest then further out as needed,
+ * so we always favor a closer, idle cpu.
+ *
+ * Returns the CPU we should wake onto.
+ */
+#if defined(ARCH_HAS_SCHED_WAKE_IDLE)
+static int wake_idle(int cpu, struct task_struct *p)
+{
+   cpumask_t tmp;
+   struct sched_domain *sd;
+   int i;
+
+   /*
+    * If it is idle, then it is the best cpu to run this task.
+    *
+    * This cpu is also the best, if it has more than one task already.
+    * Siblings must be also busy(in most cases) as they didn't already
+    * pickup the extra load from this cpu and hence we need not check
+    * sibling runqueue info. This will avoid the checks and cache miss
+    * penalities associated with that.
+    */
+   if (idle_cpu(cpu) || cpu_rq(cpu)->nr_running > 1)
+      return cpu;
+
+   for_each_domain(cpu, sd) {
+      if (sd->flags & SD_WAKE_IDLE) {
+         cpus_and(tmp, sd->span, p->cpus_allowed);
+         for_each_cpu_mask(i, tmp) {
+            if (idle_cpu(i)) {
+               if (i != task_cpu(p)) {
+                  schedstat_inc(p,
+                         se.nr_wakeups_idle);
+               }
+               return i;
+            }
+         }
+      } else {
+         break;
+      }
+   }
+   return cpu;
+}
+#else
+static inline int wake_idle(int cpu, struct task_struct *p)
+{
+   return cpu;
+}
+#endif
+
+#ifdef CONFIG_SMP
+
+static const struct sched_class fair_sched_class;
+
+static int
+wake_affine(struct rq *rq, struct sched_domain *this_sd, struct rq *this_rq,
+       struct task_struct *p, int prev_cpu, int this_cpu, int sync,
+       int idx, unsigned long load, unsigned long this_load,
+       unsigned int imbalance)
+{
+   struct task_struct *curr = this_rq->curr;
+   unsigned long tl = this_load;
+   unsigned long tl_per_task;
+
+   if (!(this_sd->flags & SD_WAKE_AFFINE))
+      return 0;
+
+   /*
+    * If the currently running task will sleep within
+    * a reasonable amount of time then attract this newly
+    * woken task:
+    */
+   if (sync && curr->sched_class == &fair_sched_class) {
+      if (curr->se.avg_overlap < sysctl_sched_migration_cost &&
+            p->se.avg_overlap < sysctl_sched_migration_cost)
+         return 1;
+   }
+
+   schedstat_inc(p, se.nr_wakeups_affine_attempts);
+   tl_per_task = cpu_avg_load_per_task(this_cpu);
+
+   /*
+    * If sync wakeup then subtract the (maximum possible)
+    * effect of the currently running task from the load
+    * of the current CPU:
+    */
+   if (sync)
+      tl -= current->se.load.weight;
+
+   if ((tl <= load && tl + target_load(prev_cpu, idx) <= tl_per_task) ||
+         100*(tl + p->se.load.weight) <= imbalance*load) {
+      /*
+       * This domain has SD_WAKE_AFFINE and
+       * p is cache cold in this domain, and
+       * there is no bad imbalance.
+       */
+      schedstat_inc(this_sd, ttwu_move_affine);
+      schedstat_inc(p, se.nr_wakeups_affine);
+
+      return 1;
+   }
+   return 0;
+}
+
+static int select_task_rq_fair(struct task_struct *p, int sync)
+{
+   struct sched_domain *sd, *this_sd = NULL;
+   int prev_cpu, this_cpu, new_cpu;
+   unsigned long load, this_load;
+   struct rq *rq, *this_rq;
+   unsigned int imbalance;
+   int idx;
+
+   prev_cpu   = task_cpu(p);
+   rq      = task_rq(p);
+   this_cpu   = smp_processor_id();
+   this_rq      = cpu_rq(this_cpu);
+   new_cpu      = prev_cpu;
+
+   /*
+    * 'this_sd' is the first domain that both
+    * this_cpu and prev_cpu are present in:
+    */
+   for_each_domain(this_cpu, sd) {
+      if (cpu_isset(prev_cpu, sd->span)) {
+         this_sd = sd;
+         break;
+      }
+   }
+
+   if (unlikely(!cpu_isset(this_cpu, p->cpus_allowed)))
+      goto out;
+
+   /*
+    * Check for affine wakeup and passive balancing possibilities.
+    */
+   if (!this_sd)
+      goto out;
+
+   idx = this_sd->wake_idx;
+
+   imbalance = 100 + (this_sd->imbalance_pct - 100) / 2;
+
+   load = source_load(prev_cpu, idx);
+   this_load = target_load(this_cpu, idx);
+
+   if (wake_affine(rq, this_sd, this_rq, p, prev_cpu, this_cpu, sync, idx,
+                 load, this_load, imbalance))
+      return this_cpu;
+
+   if (prev_cpu == this_cpu)
+      goto out;
+
+   /*
+    * Start passive balancing when half the imbalance_pct
+    * limit is reached.
+    */
+   if (this_sd->flags & SD_WAKE_BALANCE) {
+      if (imbalance*this_load <= 100*load) {
+         schedstat_inc(this_sd, ttwu_move_balance);
+         schedstat_inc(p, se.nr_wakeups_passive);
+         return this_cpu;
+      }
+   }
+
+out:
+   return wake_idle(new_cpu, p);
+}
+#endif /* CONFIG_SMP */
+
+
+/*
  * Preempt the current task with a newly woken task if needed:
  */
 static void check_preempt_wakeup(struct rq *rq, struct task_struct *p)
@@ -851,6 +1118,13 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p)
       resched_task(curr);
       return;
    }
+
+   se->last_wakeup = se->sum_exec_runtime;
+   if (unlikely(se == pse))
+      return;
+
+   cfs_rq_of(pse)->next = pse;
+
    /*
     * Batch tasks do not preempt (their preemption is driven by
     * the tick):
@@ -867,7 +1141,11 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p)
    }
 
    gran = sysctl_sched_wakeup_granularity;
-   if (unlikely(se->load.weight != NICE_0_LOAD))
+   /*
+    * More easily preempt - nice tasks, while not making
+    * it harder for + nice tasks.
+    */
+   if (unlikely(se->load.weight > NICE_0_LOAD))
       gran = calc_delta_fair(gran, &se->load);
 
    if (pse->vruntime + gran < se->vruntime)
@@ -876,6 +1154,7 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p)
 
 static struct task_struct *pick_next_task_fair(struct rq *rq)
 {
+   struct task_struct *p;
    struct cfs_rq *cfs_rq = &rq->cfs;
    struct sched_entity *se;
 
@@ -887,7 +1166,10 @@ static struct task_struct *pick_next_task_fair(struct rq *rq)
       cfs_rq = group_cfs_rq(se);
    } while (cfs_rq);
 
-   return task_of(se);
+   p = task_of(se);
+   hrtick_start_fair(rq, p);
+
+   return p;
 }
 
 /*
@@ -950,7 +1232,7 @@ static int cfs_rq_best_prio(struct cfs_rq *cfs_rq)
    struct sched_entity *curr;
    struct task_struct *p;
 
-   if (!cfs_rq->nr_running)
+   if (!cfs_rq->nr_running || !first_fair(cfs_rq))
       return MAX_PRIO;
 
    curr = cfs_rq->curr;
@@ -1042,14 +1324,14 @@ move_one_task_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
 /*
  * scheduler tick hitting a task of our scheduling class:
  */
-static void task_tick_fair(struct rq *rq, struct task_struct *curr)
+static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued)
 {
    struct cfs_rq *cfs_rq;
    struct sched_entity *se = &curr->se;
 
    for_each_sched_entity(se) {
       cfs_rq = cfs_rq_of(se);
-      entity_tick(cfs_rq, se);
+      entity_tick(cfs_rq, se, queued);
    }
 }
 
@@ -1087,6 +1369,42 @@ static void task_new_fair(struct rq *rq, struct task_struct *p)
    resched_task(rq->curr);
 }
 
+/*
+ * Priority of the task has changed. Check to see if we preempt
+ * the current task.
+ */
+static void prio_changed_fair(struct rq *rq, struct task_struct *p,
+               int oldprio, int running)
+{
+   /*
+    * Reschedule if we are currently running on this runqueue and
+    * our priority decreased, or if we are not currently running on
+    * this runqueue and our priority is higher than the current's
+    */
+   if (running) {
+      if (p->prio > oldprio)
+         resched_task(rq->curr);
+   } else
+      check_preempt_curr(rq, p);
+}
+
+/*
+ * We switched to the sched_fair class.
+ */
+static void switched_to_fair(struct rq *rq, struct task_struct *p,
+              int running)
+{
+   /*
+    * We were most likely switched from sched_rt, so
+    * kick off the schedule if running, otherwise just see
+    * if we can still preempt the current task.
+    */
+   if (running)
+      resched_task(rq->curr);
+   else
+      check_preempt_curr(rq, p);
+}
+
 /* Account for a task changing its policy or group.
  *
  * This routine is mostly called to set cfs_rq->curr field when a task
@@ -1100,6 +1418,16 @@ static void set_curr_task_fair(struct rq *rq)
       set_next_entity(cfs_rq_of(se), se);
 }
 
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static void moved_group_fair(struct task_struct *p)
+{
+   struct cfs_rq *cfs_rq = task_cfs_rq(p);
+
+   update_curr(cfs_rq);
+   place_entity(cfs_rq, &p->se, 1);
+}
+#endif
+
 /*
  * All the scheduling class methods:
  */
@@ -1108,6 +1436,9 @@ static const struct sched_class fair_sched_class = {
    .enqueue_task      = enqueue_task_fair,
    .dequeue_task      = dequeue_task_fair,
    .yield_task      = yield_task_fair,
+#ifdef CONFIG_SMP
+   .select_task_rq      = select_task_rq_fair,
+#endif /* CONFIG_SMP */
 
    .check_preempt_curr   = check_preempt_wakeup,
 
@@ -1122,6 +1453,13 @@ static const struct sched_class fair_sched_class = {
    .set_curr_task          = set_curr_task_fair,
    .task_tick      = task_tick_fair,
    .task_new      = task_new_fair,
+
+   .prio_changed      = prio_changed_fair,
+   .switched_to      = switched_to_fair,
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+   .moved_group      = moved_group_fair,
+#endif
 };
 
 #ifdef CONFIG_SCHED_DEBUG
@@ -1132,7 +1470,9 @@ static void print_cfs_stats(struct seq_file *m, int cpu)
 #ifdef CONFIG_FAIR_GROUP_SCHED
    print_cfs_rq(m, cpu, &cpu_rq(cpu)->cfs);
 #endif
+   rcu_read_lock();
    for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq)
       print_cfs_rq(m, cpu, cfs_rq);
+   rcu_read_unlock();
 }
 #endif