1 files changed, 67 insertions, 41 deletions

diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 98345e45b059..5cc1c162044f 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -283,7 +283,7 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq)
                                                    struct sched_entity,
                                                    run_node);
 
-                if (vruntime == cfs_rq->min_vruntime)
+                if (!cfs_rq->curr)
                         vruntime = se->vruntime;
                 else
                         vruntime = min_vruntime(vruntime, se->vruntime);
@@ -386,20 +386,6 @@ int sched_nr_latency_handler(struct ctl_table *table, int write,
 #endif
 
 /*
- * delta *= P[w / rw]
- */
-static inline unsigned long
-calc_delta_weight(unsigned long delta, struct sched_entity *se)
-{
-        for_each_sched_entity(se) {
-                delta = calc_delta_mine(delta,
-                                se->load.weight, &cfs_rq_of(se)->load);
-        }
-
-        return delta;
-}
-
-/*
  * delta /= w
  */
 static inline unsigned long
@@ -440,12 +426,23 @@ static u64 __sched_period(unsigned long nr_running)
  */
 static u64 sched_slice(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
-        unsigned long nr_running = cfs_rq->nr_running;
+        u64 slice = __sched_period(cfs_rq->nr_running + !se->on_rq);
 
-        if (unlikely(!se->on_rq))
-                nr_running++;
+        for_each_sched_entity(se) {
+                struct load_weight *load;
+
+                cfs_rq = cfs_rq_of(se);
+                load = &cfs_rq->load;
 
-        return calc_delta_weight(__sched_period(nr_running), se);
+                if (unlikely(!se->on_rq)) {
+                        struct load_weight lw = cfs_rq->load;
+
+                        update_load_add(&lw, se->load.weight);
+                        load = &lw;
+                }
+                slice = calc_delta_mine(slice, se->load.weight, load);
+        }
+        return slice;
 }
 
 /*
@@ -492,6 +489,8 @@ static void update_curr(struct cfs_rq *cfs_rq)
          * overflow on 32 bits):
          */
         delta_exec = (unsigned long)(now - curr->exec_start);
+        if (!delta_exec)
+                return;
 
         __update_curr(cfs_rq, curr, delta_exec);
         curr->exec_start = now;
@@ -681,9 +680,13 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
                         unsigned long thresh = sysctl_sched_latency;
 
                         /*
-                         * convert the sleeper threshold into virtual time
+                         * Convert the sleeper threshold into virtual time.
+                         * SCHED_IDLE is a special sub-class.  We care about
+                         * fairness only relative to other SCHED_IDLE tasks,
+                         * all of which have the same weight.
                          */
-                        if (sched_feat(NORMALIZED_SLEEPER))
+                        if (sched_feat(NORMALIZED_SLEEPER) &&
+                                        task_of(se)->policy != SCHED_IDLE)
                                 thresh = calc_delta_fair(thresh, se);
 
                         vruntime -= thresh;
@@ -1017,16 +1020,33 @@ static void yield_task_fair(struct rq *rq)
  * search starts with cpus closest then further out as needed,
  * so we always favor a closer, idle cpu.
  * Domains may include CPUs that are not usable for migration,
- * hence we need to mask them out (cpu_active_map)
+ * hence we need to mask them out (cpu_active_mask)
  *
  * 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;
+        unsigned int chosen_wakeup_cpu;
+        int this_cpu;
+
+        /*
+         * At POWERSAVINGS_BALANCE_WAKEUP level, if both this_cpu and prev_cpu
+         * are idle and this is not a kernel thread and this task's affinity
+         * allows it to be moved to preferred cpu, then just move!
+         */
+
+        this_cpu = smp_processor_id();
+        chosen_wakeup_cpu =
+                cpu_rq(this_cpu)->rd->sched_mc_preferred_wakeup_cpu;
+
+        if (sched_mc_power_savings >= POWERSAVINGS_BALANCE_WAKEUP &&
+                idle_cpu(cpu) && idle_cpu(this_cpu) &&
+                p->mm && !(p->flags & PF_KTHREAD) &&
+                cpu_isset(chosen_wakeup_cpu, p->cpus_allowed))
+                return chosen_wakeup_cpu;
 
         /*
          * If it is idle, then it is the best cpu to run this task.
@@ -1044,10 +1064,9 @@ static int wake_idle(int cpu, struct task_struct *p)
                 if ((sd->flags & SD_WAKE_IDLE)
                     || ((sd->flags & SD_WAKE_IDLE_FAR)
                         && !task_hot(p, task_rq(p)->clock, sd))) {
-                        cpus_and(tmp, sd->span, p->cpus_allowed);
-                        cpus_and(tmp, tmp, cpu_active_map);
-                        for_each_cpu_mask_nr(i, tmp) {
-                                if (idle_cpu(i)) {
+                        for_each_cpu_and(i, sched_domain_span(sd),
+                                         &p->cpus_allowed) {
+                                if (cpu_active(i) && idle_cpu(i)) {
                                         if (i != task_cpu(p)) {
                                                 schedstat_inc(p,
                                                        se.nr_wakeups_idle);
@@ -1240,13 +1259,13 @@ static int select_task_rq_fair(struct task_struct *p, int sync)
          * this_cpu and prev_cpu are present in:
          */
         for_each_domain(this_cpu, sd) {
-                if (cpu_isset(prev_cpu, sd->span)) {
+                if (cpumask_test_cpu(prev_cpu, sched_domain_span(sd))) {
                         this_sd = sd;
                         break;
                 }
         }
 
-        if (unlikely(!cpu_isset(this_cpu, p->cpus_allowed)))
+        if (unlikely(!cpumask_test_cpu(this_cpu, &p->cpus_allowed)))
                 goto out;
 
         /*
@@ -1328,14 +1347,18 @@ wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se)
 
 static void set_last_buddy(struct sched_entity *se)
 {
-        for_each_sched_entity(se)
-                cfs_rq_of(se)->last = se;
+        if (likely(task_of(se)->policy != SCHED_IDLE)) {
+                for_each_sched_entity(se)
+                        cfs_rq_of(se)->last = se;
+        }
 }
 
 static void set_next_buddy(struct sched_entity *se)
 {
-        for_each_sched_entity(se)
-                cfs_rq_of(se)->next = se;
+        if (likely(task_of(se)->policy != SCHED_IDLE)) {
+                for_each_sched_entity(se)
+                        cfs_rq_of(se)->next = se;
+        }
 }
 
 /*
@@ -1345,12 +1368,11 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int sync)
 {
         struct task_struct *curr = rq->curr;
         struct sched_entity *se = &curr->se, *pse = &p->se;
+        struct cfs_rq *cfs_rq = task_cfs_rq(curr);
 
-        if (unlikely(rt_prio(p->prio))) {
-                struct cfs_rq *cfs_rq = task_cfs_rq(curr);
+        update_curr(cfs_rq);
 
-                update_rq_clock(rq);
-                update_curr(cfs_rq);
+        if (unlikely(rt_prio(p->prio))) {
                 resched_task(curr);
                 return;
         }
@@ -1382,12 +1404,18 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int sync)
                 return;
 
         /*
-         * Batch tasks do not preempt (their preemption is driven by
+         * Batch and idle tasks do not preempt (their preemption is driven by
          * the tick):
          */
-        if (unlikely(p->policy == SCHED_BATCH))
+        if (unlikely(p->policy != SCHED_NORMAL))
                 return;
 
+        /* Idle tasks are by definition preempted by everybody. */
+        if (unlikely(curr->policy == SCHED_IDLE)) {
+                resched_task(curr);
+                return;
+        }
+
         if (!sched_feat(WAKEUP_PREEMPT))
                 return;
 
@@ -1606,8 +1634,6 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued)
         }
 }
 
-#define swap(a, b) do { typeof(a) tmp = (a); (a) = (b); (b) = tmp; } while (0)
-
 /*
  * Share the fairness runtime between parent and child, thus the
  * total amount of pressure for CPU stays equal - new tasks