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-rw-r--r--kernel/sched_fair.c113
1 files changed, 72 insertions, 41 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index c62ebae65cf0..354769979c02 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -699,7 +699,8 @@ account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
cfs_rq->nr_running--;
}
-#if defined CONFIG_SMP && defined CONFIG_FAIR_GROUP_SCHED
+#ifdef CONFIG_FAIR_GROUP_SCHED
+# ifdef CONFIG_SMP
static void update_cfs_rq_load_contribution(struct cfs_rq *cfs_rq,
int global_update)
{
@@ -762,6 +763,51 @@ static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update)
list_del_leaf_cfs_rq(cfs_rq);
}
+static long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg,
+ long weight_delta)
+{
+ long load_weight, load, shares;
+
+ load = cfs_rq->load.weight + weight_delta;
+
+ load_weight = atomic_read(&tg->load_weight);
+ load_weight -= cfs_rq->load_contribution;
+ load_weight += load;
+
+ shares = (tg->shares * load);
+ if (load_weight)
+ shares /= load_weight;
+
+ if (shares < MIN_SHARES)
+ shares = MIN_SHARES;
+ if (shares > tg->shares)
+ shares = tg->shares;
+
+ return shares;
+}
+
+static void update_entity_shares_tick(struct cfs_rq *cfs_rq)
+{
+ if (cfs_rq->load_unacc_exec_time > sysctl_sched_shares_window) {
+ update_cfs_load(cfs_rq, 0);
+ update_cfs_shares(cfs_rq, 0);
+ }
+}
+# else /* CONFIG_SMP */
+static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update)
+{
+}
+
+static inline long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg,
+ long weight_delta)
+{
+ return tg->shares;
+}
+
+static inline void update_entity_shares_tick(struct cfs_rq *cfs_rq)
+{
+}
+# endif /* CONFIG_SMP */
static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se,
unsigned long weight)
{
@@ -782,7 +828,7 @@ static void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta)
{
struct task_group *tg;
struct sched_entity *se;
- long load_weight, load, shares;
+ long shares;
if (!cfs_rq)
return;
@@ -791,32 +837,14 @@ static void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta)
se = tg->se[cpu_of(rq_of(cfs_rq))];
if (!se)
return;
-
- load = cfs_rq->load.weight + weight_delta;
-
- load_weight = atomic_read(&tg->load_weight);
- load_weight -= cfs_rq->load_contribution;
- load_weight += load;
-
- shares = (tg->shares * load);
- if (load_weight)
- shares /= load_weight;
-
- if (shares < MIN_SHARES)
- shares = MIN_SHARES;
- if (shares > tg->shares)
- shares = tg->shares;
+#ifndef CONFIG_SMP
+ if (likely(se->load.weight == tg->shares))
+ return;
+#endif
+ shares = calc_cfs_shares(cfs_rq, tg, weight_delta);
reweight_entity(cfs_rq_of(se), se, shares);
}
-
-static void update_entity_shares_tick(struct cfs_rq *cfs_rq)
-{
- if (cfs_rq->load_unacc_exec_time > sysctl_sched_shares_window) {
- update_cfs_load(cfs_rq, 0);
- update_cfs_shares(cfs_rq, 0);
- }
-}
#else /* CONFIG_FAIR_GROUP_SCHED */
static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update)
{
@@ -1062,6 +1090,9 @@ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
struct sched_entity *se = __pick_next_entity(cfs_rq);
s64 delta = curr->vruntime - se->vruntime;
+ if (delta < 0)
+ return;
+
if (delta > ideal_runtime)
resched_task(rq_of(cfs_rq)->curr);
}
@@ -1362,27 +1393,27 @@ static long effective_load(struct task_group *tg, int cpu, long wl, long wg)
return wl;
for_each_sched_entity(se) {
- long S, rw, s, a, b;
+ long lw, w;
- S = se->my_q->tg->shares;
- s = se->load.weight;
- rw = se->my_q->load.weight;
+ tg = se->my_q->tg;
+ w = se->my_q->load.weight;
- a = S*(rw + wl);
- b = S*rw + s*wg;
+ /* use this cpu's instantaneous contribution */
+ lw = atomic_read(&tg->load_weight);
+ lw -= se->my_q->load_contribution;
+ lw += w + wg;
- wl = s*(a-b);
+ wl += w;
- if (likely(b))
- wl /= b;
+ if (lw > 0 && wl < lw)
+ wl = (wl * tg->shares) / lw;
+ else
+ wl = tg->shares;
- /*
- * Assume the group is already running and will
- * thus already be accounted for in the weight.
- *
- * That is, moving shares between CPUs, does not
- * alter the group weight.
- */
+ /* zero point is MIN_SHARES */
+ if (wl < MIN_SHARES)
+ wl = MIN_SHARES;
+ wl -= se->load.weight;
wg = 0;
}