This commit was manufactured by cvs2svn to create tag 'planetlab_1'.

[linux-2.6.git] / kernel / sched.c

diff --git a/kernel/sched.c b/kernel/sched.c
index 20b0921..947dda2 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -349,35 +349,36 @@ static inline struct task_struct * rq_get_next_task(struct runqueue* rq)
        ckrm_lrq_t *queue;
        int idx;
        int cpu = smp_processor_id();
-
-       // it is guaranteed be the ( rq->nr_running > 0 ) check in 
-       // schedule that a task will be found.
-
+       
+       next = rq->idle;
  retry_next_class:
-       queue = rq_get_next_class(rq);
-       // BUG_ON( !queue );
-
-       array = queue->active;
-       if (unlikely(!array->nr_active)) {
-               queue->active = queue->expired;
-               queue->expired = array;
-               queue->expired_timestamp = 0;
+       if ((queue = rq_get_next_class(rq))) {
+               //check switch active/expired queue
+               array = queue->active;
+               if (unlikely(!array->nr_active)) {
+                       queue->active = queue->expired;
+                       queue->expired = array;
+                       queue->expired_timestamp = 0;
+
+                       if (queue->active->nr_active)
+                               set_top_priority(queue,
+                                                find_first_bit(queue->active->bitmap, MAX_PRIO));
+                       else {
+                               classqueue_dequeue(queue->classqueue,
+                                                  &queue->classqueue_linkobj);
+                               cpu_demand_event(get_rq_local_stat(queue,cpu),CPU_DEMAND_DEQUEUE,0);
+                       }
+                       goto retry_next_class;                          
+               }
+               BUG_ON(!array->nr_active);
 
-               if (queue->active->nr_active)
-                       set_top_priority(queue,
-                                        find_first_bit(queue->active->bitmap, MAX_PRIO));
-               else {
-                       classqueue_dequeue(queue->classqueue,
-                                          &queue->classqueue_linkobj);
-                       cpu_demand_event(get_rq_local_stat(queue,cpu),CPU_DEMAND_DEQUEUE,0);
+               idx = queue->top_priority;
+               if (queue->top_priority == MAX_PRIO) {
+                       BUG_ON(1);
                }
-               goto retry_next_class;                          
-       }
-       // BUG_ON(!array->nr_active);
 
-       idx = queue->top_priority;
-       // BUG_ON (idx == MAX_PRIO);
-       next = task_list_entry(array->queue[idx].next);
+               next = task_list_entry(array->queue[idx].next);
+       }
        return next;
 }
 #else /*! CONFIG_CKRM_CPU_SCHEDULE*/
@@ -416,6 +417,7 @@ static inline void ckrm_sched_tick(int j,int this_cpu,void* name) {}
  */
 static void dequeue_task(struct task_struct *p, prio_array_t *array)
 {
+       BUG_ON(! array);
        array->nr_active--;
        list_del(&p->run_list);
        if (list_empty(array->queue + p->prio))
@@ -2531,7 +2533,7 @@ static inline int wake_priority_sleeper(runqueue_t *rq)
        return 0;
 }
 
-DEFINE_PER_CPU(struct kernel_stat, kstat);
+DEFINE_PER_CPU(struct kernel_stat, kstat) = { { 0 } };
 EXPORT_PER_CPU_SYMBOL(kstat);
 
 /*
@@ -2898,17 +2900,14 @@ pick_next:
 #endif
        if (unlikely(!rq->nr_running)) {
                idle_balance(cpu, rq);
-                if (!rq->nr_running) {
-                        next = rq->idle;
-#ifdef CONFIG_CKRM_CPU_SCHEDULE
-                        rq->expired_timestamp = 0;
-#endif
-                        wake_sleeping_dependent(cpu, rq);
-                        goto switch_tasks;
-                }
        }
 
        next = rq_get_next_task(rq);
+       if (next == rq->idle) {
+               rq->expired_timestamp = 0;
+               wake_sleeping_dependent(cpu, rq);
+               goto switch_tasks;
+       }
 
        if (dependent_sleeper(cpu, rq, next)) {
                next = rq->idle;