1 files changed, 549 insertions, 117 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index 03ad0113801a..d87c6e5d4e8c 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -196,10 +196,28 @@ static inline int rt_bandwidth_enabled(void)
         return sysctl_sched_rt_runtime >= 0;
 }
 
-static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
+static void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period)
 {
-        ktime_t now;
+        unsigned long delta;
+        ktime_t soft, hard, now;
+
+        for (;;) {
+                if (hrtimer_active(period_timer))
+                        break;
+
+                now = hrtimer_cb_get_time(period_timer);
+                hrtimer_forward(period_timer, now, period);
 
+                soft = hrtimer_get_softexpires(period_timer);
+                hard = hrtimer_get_expires(period_timer);
+                delta = ktime_to_ns(ktime_sub(hard, soft));
+                __hrtimer_start_range_ns(period_timer, soft, delta,
+                                         HRTIMER_MODE_ABS_PINNED, 0);
+        }
+}
+
+static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
+{
         if (!rt_bandwidth_enabled() || rt_b->rt_runtime == RUNTIME_INF)
                 return;
 
@@ -207,22 +225,7 @@ static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
                 return;
 
         raw_spin_lock(&rt_b->rt_runtime_lock);
-        for (;;) {
-                unsigned long delta;
-                ktime_t soft, hard;
-
-                if (hrtimer_active(&rt_b->rt_period_timer))
-                        break;
-
-                now = hrtimer_cb_get_time(&rt_b->rt_period_timer);
-                hrtimer_forward(&rt_b->rt_period_timer, now, rt_b->rt_period);
-
-                soft = hrtimer_get_softexpires(&rt_b->rt_period_timer);
-                hard = hrtimer_get_expires(&rt_b->rt_period_timer);
-                delta = ktime_to_ns(ktime_sub(hard, soft));
-                __hrtimer_start_range_ns(&rt_b->rt_period_timer, soft, delta,
-                                HRTIMER_MODE_ABS_PINNED, 0);
-        }
+        start_bandwidth_timer(&rt_b->rt_period_timer, rt_b->rt_period);
         raw_spin_unlock(&rt_b->rt_runtime_lock);
 }
 
@@ -247,6 +250,24 @@ struct cfs_rq;
 
 static LIST_HEAD(task_groups);
 
+struct cfs_bandwidth {
+#ifdef CONFIG_CFS_BANDWIDTH
+        raw_spinlock_t lock;
+        ktime_t period;
+        u64 quota, runtime;
+        s64 hierarchal_quota;
+        u64 runtime_expires;
+
+        int idle, timer_active;
+        struct hrtimer period_timer, slack_timer;
+        struct list_head throttled_cfs_rq;
+
+        /* statistics */
+        int nr_periods, nr_throttled;
+        u64 throttled_time;
+#endif
+};
+
 /* task group related information */
 struct task_group {
         struct cgroup_subsys_state css;
@@ -278,6 +299,8 @@ struct task_group {
 #ifdef CONFIG_SCHED_AUTOGROUP
         struct autogroup *autogroup;
 #endif
+
+        struct cfs_bandwidth cfs_bandwidth;
 };
 
 /* task_group_lock serializes the addition/removal of task groups */
@@ -311,7 +334,7 @@ struct task_group root_task_group;
 /* CFS-related fields in a runqueue */
 struct cfs_rq {
         struct load_weight load;
-        unsigned long nr_running;
+        unsigned long nr_running, h_nr_running;
 
         u64 exec_clock;
         u64 min_vruntime;
@@ -377,9 +400,120 @@ struct cfs_rq {
 
         unsigned long load_contribution;
 #endif
+#ifdef CONFIG_CFS_BANDWIDTH
+        int runtime_enabled;
+        u64 runtime_expires;
+        s64 runtime_remaining;
+
+        u64 throttled_timestamp;
+        int throttled, throttle_count;
+        struct list_head throttled_list;
+#endif
 #endif
 };
 
+#ifdef CONFIG_FAIR_GROUP_SCHED
+#ifdef CONFIG_CFS_BANDWIDTH
+static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
+{
+        return &tg->cfs_bandwidth;
+}
+
+static inline u64 default_cfs_period(void);
+static int do_sched_cfs_period_timer(struct cfs_bandwidth *cfs_b, int overrun);
+static void do_sched_cfs_slack_timer(struct cfs_bandwidth *cfs_b);
+
+static enum hrtimer_restart sched_cfs_slack_timer(struct hrtimer *timer)
+{
+        struct cfs_bandwidth *cfs_b =
+                container_of(timer, struct cfs_bandwidth, slack_timer);
+        do_sched_cfs_slack_timer(cfs_b);
+
+        return HRTIMER_NORESTART;
+}
+
+static enum hrtimer_restart sched_cfs_period_timer(struct hrtimer *timer)
+{
+        struct cfs_bandwidth *cfs_b =
+                container_of(timer, struct cfs_bandwidth, period_timer);
+        ktime_t now;
+        int overrun;
+        int idle = 0;
+
+        for (;;) {
+                now = hrtimer_cb_get_time(timer);
+                overrun = hrtimer_forward(timer, now, cfs_b->period);
+
+                if (!overrun)
+                        break;
+
+                idle = do_sched_cfs_period_timer(cfs_b, overrun);
+        }
+
+        return idle ? HRTIMER_NORESTART : HRTIMER_RESTART;
+}
+
+static void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
+{
+        raw_spin_lock_init(&cfs_b->lock);
+        cfs_b->runtime = 0;
+        cfs_b->quota = RUNTIME_INF;
+        cfs_b->period = ns_to_ktime(default_cfs_period());
+
+        INIT_LIST_HEAD(&cfs_b->throttled_cfs_rq);
+        hrtimer_init(&cfs_b->period_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+        cfs_b->period_timer.function = sched_cfs_period_timer;
+        hrtimer_init(&cfs_b->slack_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+        cfs_b->slack_timer.function = sched_cfs_slack_timer;
+}
+
+static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq)
+{
+        cfs_rq->runtime_enabled = 0;
+        INIT_LIST_HEAD(&cfs_rq->throttled_list);
+}
+
+/* requires cfs_b->lock, may release to reprogram timer */
+static void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
+{
+        /*
+         * The timer may be active because we're trying to set a new bandwidth
+         * period or because we're racing with the tear-down path
+         * (timer_active==0 becomes visible before the hrtimer call-back
+         * terminates).  In either case we ensure that it's re-programmed
+         */
+        while (unlikely(hrtimer_active(&cfs_b->period_timer))) {
+                raw_spin_unlock(&cfs_b->lock);
+                /* ensure cfs_b->lock is available while we wait */
+                hrtimer_cancel(&cfs_b->period_timer);
+
+                raw_spin_lock(&cfs_b->lock);
+                /* if someone else restarted the timer then we're done */
+                if (cfs_b->timer_active)
+                        return;
+        }
+
+        cfs_b->timer_active = 1;
+        start_bandwidth_timer(&cfs_b->period_timer, cfs_b->period);
+}
+
+static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
+{
+        hrtimer_cancel(&cfs_b->period_timer);
+        hrtimer_cancel(&cfs_b->slack_timer);
+}
+#else
+static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq) {}
+static void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
+static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
+
+static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
+{
+        return NULL;
+}
+#endif /* CONFIG_CFS_BANDWIDTH */
+#endif /* CONFIG_FAIR_GROUP_SCHED */
+
 /* Real-Time classes' related field in a runqueue: */
 struct rt_rq {
         struct rt_prio_array active;
@@ -510,7 +644,7 @@ struct rq {
 
         unsigned long cpu_power;
 
-        unsigned char idle_at_tick;
+        unsigned char idle_balance;
         /* For active balancing */
         int post_schedule;
         int active_balance;
@@ -520,8 +654,6 @@ struct rq {
         int cpu;
         int online;
 
-        unsigned long avg_load_per_task;
-
         u64 rt_avg;
         u64 age_stamp;
         u64 idle_stamp;
@@ -570,7 +702,7 @@ struct rq {
 #endif
 
 #ifdef CONFIG_SMP
-        struct task_struct *wake_list;
+        struct llist_head wake_list;
 #endif
 };
 
@@ -1272,6 +1404,18 @@ void wake_up_idle_cpu(int cpu)
                 smp_send_reschedule(cpu);
 }
 
+static inline bool got_nohz_idle_kick(void)
+{
+        return idle_cpu(smp_processor_id()) && this_rq()->nohz_balance_kick;
+}
+
+#else /* CONFIG_NO_HZ */
+
+static inline bool got_nohz_idle_kick(void)
+{
+        return false;
+}
+
 #endif /* CONFIG_NO_HZ */
 
 static u64 sched_avg_period(void)
@@ -1471,24 +1615,28 @@ static inline void dec_cpu_load(struct rq *rq, unsigned long load)
         update_load_sub(&rq->load, load);
 }
 
-#if (defined(CONFIG_SMP) && defined(CONFIG_FAIR_GROUP_SCHED)) || defined(CONFIG_RT_GROUP_SCHED)
+#if defined(CONFIG_RT_GROUP_SCHED) || (defined(CONFIG_FAIR_GROUP_SCHED) && \
+                        (defined(CONFIG_SMP) || defined(CONFIG_CFS_BANDWIDTH)))
 typedef int (*tg_visitor)(struct task_group *, void *);
 
 /*
- * Iterate the full tree, calling @down when first entering a node and @up when
- * leaving it for the final time.
+ * Iterate task_group tree rooted at *from, calling @down when first entering a
+ * node and @up when leaving it for the final time.
+ *
+ * Caller must hold rcu_lock or sufficient equivalent.
  */
-static int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
+static int walk_tg_tree_from(struct task_group *from,
+                             tg_visitor down, tg_visitor up, void *data)
 {
         struct task_group *parent, *child;
         int ret;
 
-        rcu_read_lock();
-        parent = &root_task_group;
+        parent = from;
+
 down:
         ret = (*down)(parent, data);
         if (ret)
-                goto out_unlock;
+                goto out;
         list_for_each_entry_rcu(child, &parent->children, siblings) {
                 parent = child;
                 goto down;
@@ -1497,19 +1645,29 @@ up:
                 continue;
         }
         ret = (*up)(parent, data);
-        if (ret)
-                goto out_unlock;
+        if (ret || parent == from)
+                goto out;
 
         child = parent;
         parent = parent->parent;
         if (parent)
                 goto up;
-out_unlock:
-        rcu_read_unlock();
-
+out:
         return ret;
 }
 
+/*
+ * Iterate the full tree, calling @down when first entering a node and @up when
+ * leaving it for the final time.
+ *
+ * Caller must hold rcu_lock or sufficient equivalent.
+ */
+
+static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
+{
+        return walk_tg_tree_from(&root_task_group, down, up, data);
+}
+
 static int tg_nop(struct task_group *tg, void *data)
 {
         return 0;
@@ -1569,11 +1727,9 @@ static unsigned long cpu_avg_load_per_task(int cpu)
         unsigned long nr_running = ACCESS_ONCE(rq->nr_running);
 
         if (nr_running)
-                rq->avg_load_per_task = rq->load.weight / nr_running;
-        else
-                rq->avg_load_per_task = 0;
+                return rq->load.weight / nr_running;
 
-        return rq->avg_load_per_task;
+        return 0;
 }
 
 #ifdef CONFIG_PREEMPT
@@ -1806,7 +1962,6 @@ static void activate_task(struct rq *rq, struct task_struct *p, int flags)
                 rq->nr_uninterruptible--;
 
         enqueue_task(rq, p, flags);
-        inc_nr_running(rq);
 }
 
 /*
@@ -1818,7 +1973,6 @@ static void deactivate_task(struct rq *rq, struct task_struct *p, int flags)
                 rq->nr_uninterruptible++;
 
         dequeue_task(rq, p, flags);
-        dec_nr_running(rq);
 }
 
 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
@@ -2390,11 +2544,11 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
 
         /* Look for allowed, online CPU in same node. */
         for_each_cpu_and(dest_cpu, nodemask, cpu_active_mask)
-                if (cpumask_test_cpu(dest_cpu, &p->cpus_allowed))
+                if (cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
                         return dest_cpu;
 
         /* Any allowed, online CPU? */
-        dest_cpu = cpumask_any_and(&p->cpus_allowed, cpu_active_mask);
+        dest_cpu = cpumask_any_and(tsk_cpus_allowed(p), cpu_active_mask);
         if (dest_cpu < nr_cpu_ids)
                 return dest_cpu;
 
@@ -2431,7 +2585,7 @@ int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags)
          * [ this allows ->select_task() to simply return task_cpu(p) and
          *   not worry about this generic constraint ]
          */
-        if (unlikely(!cpumask_test_cpu(cpu, &p->cpus_allowed) ||
+        if (unlikely(!cpumask_test_cpu(cpu, tsk_cpus_allowed(p)) ||
                      !cpu_online(cpu)))
                 cpu = select_fallback_rq(task_cpu(p), p);
 
@@ -2556,42 +2710,26 @@ static int ttwu_remote(struct task_struct *p, int wake_flags)
 }
 
 #ifdef CONFIG_SMP
-static void sched_ttwu_do_pending(struct task_struct *list)
+static void sched_ttwu_pending(void)
 {
         struct rq *rq = this_rq();
+        struct llist_node *llist = llist_del_all(&rq->wake_list);
+        struct task_struct *p;
 
         raw_spin_lock(&rq->lock);
 
-        while (list) {
-                struct task_struct *p = list;
-                list = list->wake_entry;
+        while (llist) {
+                p = llist_entry(llist, struct task_struct, wake_entry);
+                llist = llist_next(llist);
                 ttwu_do_activate(rq, p, 0);
         }
 
         raw_spin_unlock(&rq->lock);
 }
 
-#ifdef CONFIG_HOTPLUG_CPU
-
-static void sched_ttwu_pending(void)
-{
-        struct rq *rq = this_rq();
-        struct task_struct *list = xchg(&rq->wake_list, NULL);
-
-        if (!list)
-                return;
-
-        sched_ttwu_do_pending(list);
-}
-
-#endif /* CONFIG_HOTPLUG_CPU */
-
 void scheduler_ipi(void)
 {
-        struct rq *rq = this_rq();
-        struct task_struct *list = xchg(&rq->wake_list, NULL);
-
-        if (!list)
+        if (llist_empty(&this_rq()->wake_list) && !got_nohz_idle_kick())
                 return;
 
         /*
@@ -2608,25 +2746,21 @@ void scheduler_ipi(void)
          * somewhat pessimize the simple resched case.
          */
         irq_enter();
-        sched_ttwu_do_pending(list);
+        sched_ttwu_pending();
+
+        /*
+         * Check if someone kicked us for doing the nohz idle load balance.
+         */
+        if (unlikely(got_nohz_idle_kick() && !need_resched())) {
+                this_rq()->idle_balance = 1;
+                raise_softirq_irqoff(SCHED_SOFTIRQ);
+        }
         irq_exit();
 }
 
 static void ttwu_queue_remote(struct task_struct *p, int cpu)
 {
-        struct rq *rq = cpu_rq(cpu);
-        struct task_struct *next = rq->wake_list;
-
-        for (;;) {
-                struct task_struct *old = next;
-
-                p->wake_entry = next;
-                next = cmpxchg(&rq->wake_list, old, p);
-                if (next == old)
-                        break;
-        }
-
-        if (!next)
+        if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list))
                 smp_send_reschedule(cpu);
 }
 
@@ -2848,19 +2982,23 @@ void sched_fork(struct task_struct *p)
         p->state = TASK_RUNNING;
 
         /*
+         * Make sure we do not leak PI boosting priority to the child.
+         */
+        p->prio = current->normal_prio;
+
+        /*
          * Revert to default priority/policy on fork if requested.
          */
         if (unlikely(p->sched_reset_on_fork)) {
-                if (p->policy == SCHED_FIFO || p->policy == SCHED_RR) {
+                if (task_has_rt_policy(p)) {
                         p->policy = SCHED_NORMAL;
-                        p->normal_prio = p->static_prio;
-                }
-
-                if (PRIO_TO_NICE(p->static_prio) < 0) {
                         p->static_prio = NICE_TO_PRIO(0);
-                        p->normal_prio = p->static_prio;
-                        set_load_weight(p);
-                }
+                        p->rt_priority = 0;
+                } else if (PRIO_TO_NICE(p->static_prio) < 0)
+                        p->static_prio = NICE_TO_PRIO(0);
+
+                p->prio = p->normal_prio = __normal_prio(p);
+                set_load_weight(p);
 
                 /*
                  * We don't need the reset flag anymore after the fork. It has
@@ -2869,11 +3007,6 @@ void sched_fork(struct task_struct *p)
                 p->sched_reset_on_fork = 0;
         }
 
-        /*
-         * Make sure we do not leak PI boosting priority to the child.
-         */
-        p->prio = current->normal_prio;
-
         if (!rt_prio(p->prio))
                 p->sched_class = &fair_sched_class;
 
@@ -4116,7 +4249,7 @@ void scheduler_tick(void)
         perf_event_task_tick();
 
 #ifdef CONFIG_SMP
-        rq->idle_at_tick = idle_cpu(cpu);
+        rq->idle_balance = idle_cpu(cpu);
         trigger_load_balance(rq, cpu);
 #endif
 }
@@ -4240,7 +4373,7 @@ pick_next_task(struct rq *rq)
          * Optimization: we know that if all tasks are in
          * the fair class we can call that function directly:
          */
-        if (likely(rq->nr_running == rq->cfs.nr_running)) {
+        if (likely(rq->nr_running == rq->cfs.h_nr_running)) {
                 p = fair_sched_class.pick_next_task(rq);
                 if (likely(p))
                         return p;
@@ -5026,7 +5159,20 @@ EXPORT_SYMBOL(task_nice);
  */
 int idle_cpu(int cpu)
 {
-        return cpu_curr(cpu) == cpu_rq(cpu)->idle;
+        struct rq *rq = cpu_rq(cpu);
+
+        if (rq->curr != rq->idle)
+                return 0;
+
+        if (rq->nr_running)
+                return 0;
+
+#ifdef CONFIG_SMP
+        if (!llist_empty(&rq->wake_list))
+                return 0;
+#endif
+
+        return 1;
 }
 
 /**
@@ -5876,7 +6022,7 @@ void show_state_filter(unsigned long state_filter)
         printk(KERN_INFO
                 "  task                        PC stack   pid father\n");
 #endif
-        read_lock(&tasklist_lock);
+        rcu_read_lock();
         do_each_thread(g, p) {
                 /*
                  * reset the NMI-timeout, listing all files on a slow
@@ -5892,7 +6038,7 @@ void show_state_filter(unsigned long state_filter)
 #ifdef CONFIG_SCHED_DEBUG
         sysrq_sched_debug_show();
 #endif
-        read_unlock(&tasklist_lock);
+        rcu_read_unlock();
         /*
          * Only show locks if all tasks are dumped:
          */
@@ -6007,10 +6153,9 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
 {
         if (p->sched_class && p->sched_class->set_cpus_allowed)
                 p->sched_class->set_cpus_allowed(p, new_mask);
-        else {
-                cpumask_copy(&p->cpus_allowed, new_mask);
-                p->rt.nr_cpus_allowed = cpumask_weight(new_mask);
-        }
+
+        cpumask_copy(&p->cpus_allowed, new_mask);
+        p->rt.nr_cpus_allowed = cpumask_weight(new_mask);
 }
 
 /*
@@ -6108,7 +6253,7 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
         if (task_cpu(p) != src_cpu)
                 goto done;
         /* Affinity changed (again). */
-        if (!cpumask_test_cpu(dest_cpu, &p->cpus_allowed))
+        if (!cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
                 goto fail;
 
         /*
@@ -6189,6 +6334,30 @@ static void calc_global_load_remove(struct rq *rq)
         rq->calc_load_active = 0;
 }
 
+#ifdef CONFIG_CFS_BANDWIDTH
+static void unthrottle_offline_cfs_rqs(struct rq *rq)
+{
+        struct cfs_rq *cfs_rq;
+
+        for_each_leaf_cfs_rq(rq, cfs_rq) {
+                struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
+
+                if (!cfs_rq->runtime_enabled)
+                        continue;
+
+                /*
+                 * clock_task is not advancing so we just need to make sure
+                 * there's some valid quota amount
+                 */
+                cfs_rq->runtime_remaining = cfs_b->quota;
+                if (cfs_rq_throttled(cfs_rq))
+                        unthrottle_cfs_rq(cfs_rq);
+        }
+}
+#else
+static void unthrottle_offline_cfs_rqs(struct rq *rq) {}
+#endif
+
 /*
  * Migrate all tasks from the rq, sleeping tasks will be migrated by
  * try_to_wake_up()->select_task_rq().
@@ -6214,6 +6383,9 @@ static void migrate_tasks(unsigned int dead_cpu)
          */
         rq->stop = NULL;
 
+        /* Ensure any throttled groups are reachable by pick_next_task */
+        unthrottle_offline_cfs_rqs(rq);
+
         for ( ; ; ) {
                 /*
                  * There's this thread running, bail when that's the only
@@ -7957,6 +8129,7 @@ static void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
         /* allow initial update_cfs_load() to truncate */
         cfs_rq->load_stamp = 1;
 #endif
+        init_cfs_rq_runtime(cfs_rq);
 
         tg->cfs_rq[cpu] = cfs_rq;
         tg->se[cpu] = se;
@@ -8096,6 +8269,7 @@ void __init sched_init(void)
                  * We achieve this by letting root_task_group's tasks sit
                  * directly in rq->cfs (i.e root_task_group->se[] = NULL).
                  */
+                init_cfs_bandwidth(&root_task_group.cfs_bandwidth);
                 init_tg_cfs_entry(&root_task_group, &rq->cfs, NULL, i, NULL);
 #endif /* CONFIG_FAIR_GROUP_SCHED */
 
@@ -8125,7 +8299,6 @@ void __init sched_init(void)
                 rq_attach_root(rq, &def_root_domain);
 #ifdef CONFIG_NO_HZ
                 rq->nohz_balance_kick = 0;
-                init_sched_softirq_csd(&per_cpu(remote_sched_softirq_cb, i));
 #endif
 #endif
                 init_rq_hrtick(rq);
@@ -8336,6 +8509,8 @@ static void free_fair_sched_group(struct task_group *tg)
 {
         int i;
 
+        destroy_cfs_bandwidth(tg_cfs_bandwidth(tg));
+
         for_each_possible_cpu(i) {
                 if (tg->cfs_rq)
                         kfree(tg->cfs_rq[i]);
@@ -8363,6 +8538,8 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
 
         tg->shares = NICE_0_LOAD;
 
+        init_cfs_bandwidth(tg_cfs_bandwidth(tg));
+
         for_each_possible_cpu(i) {
                 cfs_rq = kzalloc_node(sizeof(struct cfs_rq),
                                       GFP_KERNEL, cpu_to_node(i));
@@ -8638,12 +8815,7 @@ unsigned long sched_group_shares(struct task_group *tg)
 }
 #endif
 
-#ifdef CONFIG_RT_GROUP_SCHED
-/*
- * Ensure that the real time constraints are schedulable.
- */
-static DEFINE_MUTEX(rt_constraints_mutex);
-
+#if defined(CONFIG_RT_GROUP_SCHED) || defined(CONFIG_CFS_BANDWIDTH)
 static unsigned long to_ratio(u64 period, u64 runtime)
 {
         if (runtime == RUNTIME_INF)
@@ -8651,6 +8823,13 @@ static unsigned long to_ratio(u64 period, u64 runtime)
 
         return div64_u64(runtime << 20, period);
 }
+#endif
+
+#ifdef CONFIG_RT_GROUP_SCHED
+/*
+ * Ensure that the real time constraints are schedulable.
+ */
+static DEFINE_MUTEX(rt_constraints_mutex);
 
 /* Must be called with tasklist_lock held */
 static inline int tg_has_rt_tasks(struct task_group *tg)
@@ -8671,7 +8850,7 @@ struct rt_schedulable_data {
         u64 rt_runtime;
 };
 
-static int tg_schedulable(struct task_group *tg, void *data)
+static int tg_rt_schedulable(struct task_group *tg, void *data)
 {
         struct rt_schedulable_data *d = data;
         struct task_group *child;
@@ -8729,16 +8908,22 @@ static int tg_schedulable(struct task_group *tg, void *data)
 
 static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
 {
+        int ret;
+
         struct rt_schedulable_data data = {
                 .tg = tg,
                 .rt_period = period,
                 .rt_runtime = runtime,
         };
 
-        return walk_tg_tree(tg_schedulable, tg_nop, &data);
+        rcu_read_lock();
+        ret = walk_tg_tree(tg_rt_schedulable, tg_nop, &data);
+        rcu_read_unlock();
+
+        return ret;
 }
 
-static int tg_set_bandwidth(struct task_group *tg,
+static int tg_set_rt_bandwidth(struct task_group *tg,
                 u64 rt_period, u64 rt_runtime)
 {
         int i, err = 0;
@@ -8777,7 +8962,7 @@ int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us)
         if (rt_runtime_us < 0)
                 rt_runtime = RUNTIME_INF;
 
-        return tg_set_bandwidth(tg, rt_period, rt_runtime);
+        return tg_set_rt_bandwidth(tg, rt_period, rt_runtime);
 }
 
 long sched_group_rt_runtime(struct task_group *tg)
@@ -8802,7 +8987,7 @@ int sched_group_set_rt_period(struct task_group *tg, long rt_period_us)
         if (rt_period == 0)
                 return -EINVAL;
 
-        return tg_set_bandwidth(tg, rt_period, rt_runtime);
+        return tg_set_rt_bandwidth(tg, rt_period, rt_runtime);
 }
 
 long sched_group_rt_period(struct task_group *tg)
@@ -8992,6 +9177,238 @@ static u64 cpu_shares_read_u64(struct cgroup *cgrp, struct cftype *cft)
 
         return (u64) scale_load_down(tg->shares);
 }
+
+#ifdef CONFIG_CFS_BANDWIDTH
+static DEFINE_MUTEX(cfs_constraints_mutex);
+
+const u64 max_cfs_quota_period = 1 * NSEC_PER_SEC; /* 1s */
+const u64 min_cfs_quota_period = 1 * NSEC_PER_MSEC; /* 1ms */
+
+static int __cfs_schedulable(struct task_group *tg, u64 period, u64 runtime);
+
+static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota)
+{
+        int i, ret = 0, runtime_enabled;
+        struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(tg);
+
+        if (tg == &root_task_group)
+                return -EINVAL;
+
+        /*
+         * Ensure we have at some amount of bandwidth every period.  This is
+         * to prevent reaching a state of large arrears when throttled via
+         * entity_tick() resulting in prolonged exit starvation.
+         */
+        if (quota < min_cfs_quota_period || period < min_cfs_quota_period)
+                return -EINVAL;
+
+        /*
+         * Likewise, bound things on the otherside by preventing insane quota
+         * periods.  This also allows us to normalize in computing quota
+         * feasibility.
+         */
+        if (period > max_cfs_quota_period)
+                return -EINVAL;
+
+        mutex_lock(&cfs_constraints_mutex);
+        ret = __cfs_schedulable(tg, period, quota);
+        if (ret)
+                goto out_unlock;
+
+        runtime_enabled = quota != RUNTIME_INF;
+        raw_spin_lock_irq(&cfs_b->lock);
+        cfs_b->period = ns_to_ktime(period);
+        cfs_b->quota = quota;
+
+        __refill_cfs_bandwidth_runtime(cfs_b);
+        /* restart the period timer (if active) to handle new period expiry */
+        if (runtime_enabled && cfs_b->timer_active) {
+                /* force a reprogram */
+                cfs_b->timer_active = 0;
+                __start_cfs_bandwidth(cfs_b);
+        }
+        raw_spin_unlock_irq(&cfs_b->lock);
+
+        for_each_possible_cpu(i) {
+                struct cfs_rq *cfs_rq = tg->cfs_rq[i];
+                struct rq *rq = rq_of(cfs_rq);
+
+                raw_spin_lock_irq(&rq->lock);
+                cfs_rq->runtime_enabled = runtime_enabled;
+                cfs_rq->runtime_remaining = 0;
+
+                if (cfs_rq_throttled(cfs_rq))
+                        unthrottle_cfs_rq(cfs_rq);
+                raw_spin_unlock_irq(&rq->lock);
+        }
+out_unlock:
+        mutex_unlock(&cfs_constraints_mutex);
+
+        return ret;
+}
+
+int tg_set_cfs_quota(struct task_group *tg, long cfs_quota_us)
+{
+        u64 quota, period;
+
+        period = ktime_to_ns(tg_cfs_bandwidth(tg)->period);
+        if (cfs_quota_us < 0)
+                quota = RUNTIME_INF;
+        else
+                quota = (u64)cfs_quota_us * NSEC_PER_USEC;
+
+        return tg_set_cfs_bandwidth(tg, period, quota);
+}
+
+long tg_get_cfs_quota(struct task_group *tg)
+{
+        u64 quota_us;
+
+        if (tg_cfs_bandwidth(tg)->quota == RUNTIME_INF)
+                return -1;
+
+        quota_us = tg_cfs_bandwidth(tg)->quota;
+        do_div(quota_us, NSEC_PER_USEC);
+
+        return quota_us;
+}
+
+int tg_set_cfs_period(struct task_group *tg, long cfs_period_us)
+{
+        u64 quota, period;
+
+        period = (u64)cfs_period_us * NSEC_PER_USEC;
+        quota = tg_cfs_bandwidth(tg)->quota;
+
+        if (period <= 0)
+                return -EINVAL;
+
+        return tg_set_cfs_bandwidth(tg, period, quota);
+}
+
+long tg_get_cfs_period(struct task_group *tg)
+{
+        u64 cfs_period_us;
+
+        cfs_period_us = ktime_to_ns(tg_cfs_bandwidth(tg)->period);
+        do_div(cfs_period_us, NSEC_PER_USEC);
+
+        return cfs_period_us;
+}
+
+static s64 cpu_cfs_quota_read_s64(struct cgroup *cgrp, struct cftype *cft)
+{
+        return tg_get_cfs_quota(cgroup_tg(cgrp));
+}
+
+static int cpu_cfs_quota_write_s64(struct cgroup *cgrp, struct cftype *cftype,
+                                s64 cfs_quota_us)
+{
+        return tg_set_cfs_quota(cgroup_tg(cgrp), cfs_quota_us);
+}
+
+static u64 cpu_cfs_period_read_u64(struct cgroup *cgrp, struct cftype *cft)
+{
+        return tg_get_cfs_period(cgroup_tg(cgrp));
+}
+
+static int cpu_cfs_period_write_u64(struct cgroup *cgrp, struct cftype *cftype,
+                                u64 cfs_period_us)
+{
+        return tg_set_cfs_period(cgroup_tg(cgrp), cfs_period_us);
+}
+
+struct cfs_schedulable_data {
+        struct task_group *tg;
+        u64 period, quota;
+};
+
+/*
+ * normalize group quota/period to be quota/max_period
+ * note: units are usecs
+ */
+static u64 normalize_cfs_quota(struct task_group *tg,
+                               struct cfs_schedulable_data *d)
+{
+        u64 quota, period;
+
+        if (tg == d->tg) {
+                period = d->period;
+                quota = d->quota;
+        } else {
+                period = tg_get_cfs_period(tg);
+                quota = tg_get_cfs_quota(tg);
+        }
+
+        /* note: these should typically be equivalent */
+        if (quota == RUNTIME_INF || quota == -1)
+                return RUNTIME_INF;
+
+        return to_ratio(period, quota);
+}
+
+static int tg_cfs_schedulable_down(struct task_group *tg, void *data)
+{
+        struct cfs_schedulable_data *d = data;
+        struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(tg);
+        s64 quota = 0, parent_quota = -1;
+
+        if (!tg->parent) {
+                quota = RUNTIME_INF;
+        } else {
+                struct cfs_bandwidth *parent_b = tg_cfs_bandwidth(tg->parent);
+
+                quota = normalize_cfs_quota(tg, d);
+                parent_quota = parent_b->hierarchal_quota;
+
+                /*
+                 * ensure max(child_quota) <= parent_quota, inherit when no
+                 * limit is set
+                 */
+                if (quota == RUNTIME_INF)
+                        quota = parent_quota;
+                else if (parent_quota != RUNTIME_INF && quota > parent_quota)
+                        return -EINVAL;
+        }
+        cfs_b->hierarchal_quota = quota;
+
+        return 0;
+}
+
+static int __cfs_schedulable(struct task_group *tg, u64 period, u64 quota)
+{
+        int ret;
+        struct cfs_schedulable_data data = {
+                .tg = tg,
+                .period = period,
+                .quota = quota,
+        };
+
+        if (quota != RUNTIME_INF) {
+                do_div(data.period, NSEC_PER_USEC);
+                do_div(data.quota, NSEC_PER_USEC);
+        }
+
+        rcu_read_lock();
+        ret = walk_tg_tree(tg_cfs_schedulable_down, tg_nop, &data);
+        rcu_read_unlock();
+
+        return ret;
+}
+
+static int cpu_stats_show(struct cgroup *cgrp, struct cftype *cft,
+                struct cgroup_map_cb *cb)
+{
+        struct task_group *tg = cgroup_tg(cgrp);
+        struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(tg);
+
+        cb->fill(cb, "nr_periods", cfs_b->nr_periods);
+        cb->fill(cb, "nr_throttled", cfs_b->nr_throttled);
+        cb->fill(cb, "throttled_time", cfs_b->throttled_time);
+
+        return 0;
+}
+#endif /* CONFIG_CFS_BANDWIDTH */
 #endif /* CONFIG_FAIR_GROUP_SCHED */
 
 #ifdef CONFIG_RT_GROUP_SCHED
@@ -9026,6 +9443,22 @@ static struct cftype cpu_files[] = {
                 .write_u64 = cpu_shares_write_u64,
         },
 #endif
+#ifdef CONFIG_CFS_BANDWIDTH
+        {
+                .name = "cfs_quota_us",
+                .read_s64 = cpu_cfs_quota_read_s64,
+                .write_s64 = cpu_cfs_quota_write_s64,
+        },
+        {
+                .name = "cfs_period_us",
+                .read_u64 = cpu_cfs_period_read_u64,
+                .write_u64 = cpu_cfs_period_write_u64,
+        },
+        {
+                .name = "stat",
+                .read_map = cpu_stats_show,
+        },
+#endif
 #ifdef CONFIG_RT_GROUP_SCHED
         {
                 .name = "rt_runtime_us",
@@ -9335,4 +9768,3 @@ struct cgroup_subsys cpuacct_subsys = {
         .subsys_id = cpuacct_subsys_id,
 };
 #endif  /* CONFIG_CGROUP_CPUACCT */
-