sched/pelt: Check that *_avg are null when *_sum are

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

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index a2c30e5..198514d 100644 (file)
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -3453,10 +3453,9 @@ update_tg_cfs_runnable(struct cfs_rq *cfs_rq, struct sched_entity *se, struct cf
 static inline void
 update_tg_cfs_load(struct cfs_rq *cfs_rq, struct sched_entity *se, struct cfs_rq *gcfs_rq)
 {
-       long delta_avg, running_sum, runnable_sum = gcfs_rq->prop_runnable_sum;
+       long delta, running_sum, runnable_sum = gcfs_rq->prop_runnable_sum;
        unsigned long load_avg;
        u64 load_sum = 0;
-       s64 delta_sum;
        u32 divider;
 
        if (!runnable_sum)
@@ -3503,13 +3502,13 @@ update_tg_cfs_load(struct cfs_rq *cfs_rq, struct sched_entity *se, struct cfs_rq
        load_sum = (s64)se_weight(se) * runnable_sum;
        load_avg = div_s64(load_sum, divider);
 
-       delta_sum = load_sum - (s64)se_weight(se) * se->avg.load_sum;
-       delta_avg = load_avg - se->avg.load_avg;
+       delta = load_avg - se->avg.load_avg;
 
        se->avg.load_sum = runnable_sum;
        se->avg.load_avg = load_avg;
-       add_positive(&cfs_rq->avg.load_avg, delta_avg);
-       add_positive(&cfs_rq->avg.load_sum, delta_sum);
+
+       add_positive(&cfs_rq->avg.load_avg, delta);
+       cfs_rq->avg.load_sum = cfs_rq->avg.load_avg * divider;
 }
 
 static inline void add_tg_cfs_propagate(struct cfs_rq *cfs_rq, long runnable_sum)
@@ -3720,11 +3719,17 @@ static void attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s
  */
 static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
+       /*
+        * cfs_rq->avg.period_contrib can be used for both cfs_rq and se.
+        * See ___update_load_avg() for details.
+        */
+       u32 divider = get_pelt_divider(&cfs_rq->avg);
+
        dequeue_load_avg(cfs_rq, se);
        sub_positive(&cfs_rq->avg.util_avg, se->avg.util_avg);
-       sub_positive(&cfs_rq->avg.util_sum, se->avg.util_sum);
+       cfs_rq->avg.util_sum = cfs_rq->avg.util_avg * divider;
        sub_positive(&cfs_rq->avg.runnable_avg, se->avg.runnable_avg);
-       sub_positive(&cfs_rq->avg.runnable_sum, se->avg.runnable_sum);
+       cfs_rq->avg.runnable_sum = cfs_rq->avg.runnable_avg * divider;
 
        add_tg_cfs_propagate(cfs_rq, -se->avg.load_sum);
 
@@ -8021,6 +8026,15 @@ static inline bool cfs_rq_is_decayed(struct cfs_rq *cfs_rq)
        if (cfs_rq->avg.runnable_sum)
                return false;
 
+       /*
+        * _avg must be null when _sum are null because _avg = _sum / divider
+        * Make sure that rounding and/or propagation of PELT values never
+        * break this.
+        */
+       SCHED_WARN_ON(cfs_rq->avg.load_avg ||
+                     cfs_rq->avg.util_avg ||
+                     cfs_rq->avg.runnable_avg);
+
        return true;
 }
 
@@ -8047,7 +8061,7 @@ static bool __update_blocked_fair(struct rq *rq, bool *done)
                /* Propagate pending load changes to the parent, if any: */
                se = cfs_rq->tg->se[cpu];
                if (se && !skip_blocked_update(se))
-                       update_load_avg(cfs_rq_of(se), se, 0);
+                       update_load_avg(cfs_rq_of(se), se, UPDATE_TG);
 
                /*
                 * There can be a lot of idle CPU cgroups.  Don't let fully