sched: introduce se->vruntime

[safe/jmp/linux-2.6] / kernel / sched_fair.c

diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index b46f807..a2af09c 100644 (file)
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -92,14 +92,16 @@ unsigned int sysctl_sched_runtime_limit __read_mostly;
  */
 enum {
        SCHED_FEAT_FAIR_SLEEPERS        = 1,
-       SCHED_FEAT_SLEEPER_AVG          = 2,
-       SCHED_FEAT_SLEEPER_LOAD_AVG     = 4,
-       SCHED_FEAT_START_DEBIT          = 8,
-       SCHED_FEAT_SKIP_INITIAL         = 16,
+       SCHED_FEAT_NEW_FAIR_SLEEPERS    = 2,
+       SCHED_FEAT_SLEEPER_AVG          = 4,
+       SCHED_FEAT_SLEEPER_LOAD_AVG     = 8,
+       SCHED_FEAT_START_DEBIT          = 16,
+       SCHED_FEAT_SKIP_INITIAL         = 32,
 };
 
 const_debug unsigned int sysctl_sched_features =
-               SCHED_FEAT_FAIR_SLEEPERS        *1 |
+               SCHED_FEAT_FAIR_SLEEPERS        *0 |
+               SCHED_FEAT_NEW_FAIR_SLEEPERS    *1 |
                SCHED_FEAT_SLEEPER_AVG          *0 |
                SCHED_FEAT_SLEEPER_LOAD_AVG     *1 |
                SCHED_FEAT_START_DEBIT          *1 |
@@ -145,6 +147,19 @@ static inline struct task_struct *task_of(struct sched_entity *se)
  * Scheduling class tree data structure manipulation methods:
  */
 
+static inline void
+set_leftmost(struct cfs_rq *cfs_rq, struct rb_node *leftmost)
+{
+       struct sched_entity *se;
+
+       cfs_rq->rb_leftmost = leftmost;
+       if (leftmost) {
+               se = rb_entry(leftmost, struct sched_entity, run_node);
+               cfs_rq->min_vruntime = max(se->vruntime,
+                                               cfs_rq->min_vruntime);
+       }
+}
+
 /*
  * Enqueue an entity into the rb-tree:
  */
@@ -180,7 +195,7 @@ __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
         * used):
         */
        if (leftmost)
-               cfs_rq->rb_leftmost = &se->run_node;
+               set_leftmost(cfs_rq, &se->run_node);
 
        rb_link_node(&se->run_node, parent, link);
        rb_insert_color(&se->run_node, &cfs_rq->tasks_timeline);
@@ -195,7 +210,8 @@ 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);
+               set_leftmost(cfs_rq, rb_next(&se->run_node));
+
        rb_erase(&se->run_node, &cfs_rq->tasks_timeline);
        update_load_sub(&cfs_rq->load, se->load.weight);
        cfs_rq->nr_running--;
@@ -336,7 +352,7 @@ static inline void
 __update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr,
              unsigned long delta_exec)
 {
-       unsigned long delta, delta_fair, delta_mine;
+       unsigned long delta, delta_fair, delta_mine, delta_exec_weighted;
        struct load_weight *lw = &cfs_rq->load;
        unsigned long load = lw->weight;
 
@@ -344,6 +360,12 @@ __update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr,
 
        curr->sum_exec_runtime += delta_exec;
        cfs_rq->exec_clock += delta_exec;
+       delta_exec_weighted = delta_exec;
+       if (unlikely(curr->load.weight != NICE_0_LOAD)) {
+               delta_exec_weighted = calc_delta_fair(delta_exec_weighted,
+                                                       &curr->load);
+       }
+       curr->vruntime += delta_exec_weighted;
 
        if (unlikely(!load))
                return;
@@ -413,8 +435,6 @@ calc_weighted(unsigned long delta, struct sched_entity *se)
  */
 static void update_stats_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
-       s64 key;
-
        /*
         * Are we enqueueing a waiting task? (for current tasks
         * a dequeue/enqueue event is a NOP)
@@ -424,28 +444,7 @@ static void update_stats_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
        /*
         * Update the key:
         */
-       key = cfs_rq->fair_clock;
-
-       /*
-        * Optimize the common nice 0 case:
-        */
-       if (likely(se->load.weight == NICE_0_LOAD)) {
-               key -= se->wait_runtime;
-       } else {
-               u64 tmp;
-
-               if (se->wait_runtime < 0) {
-                       tmp = -se->wait_runtime;
-                       key += (tmp * se->load.inv_weight) >>
-                                       (WMULT_SHIFT - NICE_0_SHIFT);
-               } else {
-                       tmp = se->wait_runtime;
-                       key -= (tmp * se->load.inv_weight) >>
-                                       (WMULT_SHIFT - NICE_0_SHIFT);
-               }
-       }
-
-       se->fair_key = key;
+       se->fair_key = se->vruntime;
 }
 
 /*
@@ -615,8 +614,22 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int wakeup)
         */
        update_curr(cfs_rq);
 
-       if (wakeup)
+       if (wakeup) {
+               u64 min_runtime, latency;
+
+               min_runtime = cfs_rq->min_vruntime;
+               min_runtime += sysctl_sched_latency/2;
+
+               if (sched_feat(NEW_FAIR_SLEEPERS)) {
+                       latency = calc_weighted(sysctl_sched_latency, se);
+                       if (min_runtime > latency)
+                               min_runtime -= latency;
+               }
+
+               se->vruntime = max(se->vruntime, min_runtime);
+
                enqueue_sleeper(cfs_rq, se);
+       }
 
        update_stats_enqueue(cfs_rq, se);
        __enqueue_entity(cfs_rq, se);
@@ -1155,6 +1168,8 @@ static void task_new_fair(struct rq *rq, struct task_struct *p)
        if (sched_feat(START_DEBIT))
                se->wait_runtime = -(sched_granularity(cfs_rq) / 2);
 
+       se->vruntime = cfs_rq->min_vruntime;
+       update_stats_enqueue(cfs_rq, se);
        __enqueue_entity(cfs_rq, se);
        resched_task(rq->curr);
 }