sched: fix incorrect irq lock usage in normalize_rt_tasks()
[sfrench/cifs-2.6.git] / kernel / sched.c
index b9ee0f4db66a07a749a7f774dc0fec1053e9e3ed..88a17c7128c3b4639a6bf69703a01a5ca4ffd85a 100644 (file)
@@ -65,6 +65,7 @@
 #include <linux/reciprocal_div.h>
 #include <linux/unistd.h>
 #include <linux/pagemap.h>
+#include <linux/hrtimer.h>
 
 #include <asm/tlb.h>
 #include <asm/irq_regs.h>
@@ -160,6 +161,8 @@ struct rt_prio_array {
 
 struct cfs_rq;
 
+static LIST_HEAD(task_groups);
+
 /* task group related information */
 struct task_group {
 #ifdef CONFIG_FAIR_CGROUP_SCHED
@@ -170,6 +173,11 @@ struct task_group {
        /* runqueue "owned" by this group on each cpu */
        struct cfs_rq **cfs_rq;
 
+       struct sched_rt_entity **rt_se;
+       struct rt_rq **rt_rq;
+
+       unsigned int rt_ratio;
+
        /*
         * shares assigned to a task group governs how much of cpu bandwidth
         * is allocated to the group. The more shares a group has, the more is
@@ -207,6 +215,7 @@ struct task_group {
        unsigned long shares;
 
        struct rcu_head rcu;
+       struct list_head list;
 };
 
 /* Default task group's sched entity on each cpu */
@@ -214,13 +223,19 @@ static DEFINE_PER_CPU(struct sched_entity, init_sched_entity);
 /* Default task group's cfs_rq on each cpu */
 static DEFINE_PER_CPU(struct cfs_rq, init_cfs_rq) ____cacheline_aligned_in_smp;
 
+static DEFINE_PER_CPU(struct sched_rt_entity, init_sched_rt_entity);
+static DEFINE_PER_CPU(struct rt_rq, init_rt_rq) ____cacheline_aligned_in_smp;
+
 static struct sched_entity *init_sched_entity_p[NR_CPUS];
 static struct cfs_rq *init_cfs_rq_p[NR_CPUS];
 
-/* task_group_mutex serializes add/remove of task groups and also changes to
+static struct sched_rt_entity *init_sched_rt_entity_p[NR_CPUS];
+static struct rt_rq *init_rt_rq_p[NR_CPUS];
+
+/* task_group_lock serializes add/remove of task groups and also changes to
  * a task group's cpu shares.
  */
-static DEFINE_MUTEX(task_group_mutex);
+static DEFINE_SPINLOCK(task_group_lock);
 
 /* doms_cur_mutex serializes access to doms_cur[] array */
 static DEFINE_MUTEX(doms_cur_mutex);
@@ -239,6 +254,9 @@ static void set_se_shares(struct sched_entity *se, unsigned long shares);
 struct task_group init_task_group = {
        .se     = init_sched_entity_p,
        .cfs_rq = init_cfs_rq_p,
+
+       .rt_se  = init_sched_rt_entity_p,
+       .rt_rq  = init_rt_rq_p,
 };
 
 #ifdef CONFIG_FAIR_USER_SCHED
@@ -268,20 +286,13 @@ static inline struct task_group *task_group(struct task_struct *p)
 }
 
 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
-static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu)
+static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
 {
        p->se.cfs_rq = task_group(p)->cfs_rq[cpu];
        p->se.parent = task_group(p)->se[cpu];
-}
-
-static inline void lock_task_group_list(void)
-{
-       mutex_lock(&task_group_mutex);
-}
 
-static inline void unlock_task_group_list(void)
-{
-       mutex_unlock(&task_group_mutex);
+       p->rt.rt_rq  = task_group(p)->rt_rq[cpu];
+       p->rt.parent = task_group(p)->rt_se[cpu];
 }
 
 static inline void lock_doms_cur(void)
@@ -296,9 +307,7 @@ static inline void unlock_doms_cur(void)
 
 #else
 
-static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu) { }
-static inline void lock_task_group_list(void) { }
-static inline void unlock_task_group_list(void) { }
+static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
 static inline void lock_doms_cur(void) { }
 static inline void unlock_doms_cur(void) { }
 
@@ -341,13 +350,23 @@ struct cfs_rq {
 /* Real-Time classes' related field in a runqueue: */
 struct rt_rq {
        struct rt_prio_array active;
-       int rt_load_balance_idx;
-       struct list_head *rt_load_balance_head, *rt_load_balance_curr;
        unsigned long rt_nr_running;
+#if defined CONFIG_SMP || defined CONFIG_FAIR_GROUP_SCHED
+       int highest_prio; /* highest queued rt task prio */
+#endif
+#ifdef CONFIG_SMP
        unsigned long rt_nr_migratory;
-       /* highest queued rt task prio */
-       int highest_prio;
        int overloaded;
+#endif
+       int rt_throttled;
+       u64 rt_time;
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+       struct rq *rq;
+       struct list_head leaf_rt_rq_list;
+       struct task_group *tg;
+       struct sched_rt_entity *rt_se;
+#endif
 };
 
 #ifdef CONFIG_SMP
@@ -409,11 +428,15 @@ struct rq {
        u64 nr_switches;
 
        struct cfs_rq cfs;
+       struct rt_rq rt;
+       u64 rt_period_expire;
+       int rt_throttled;
+
 #ifdef CONFIG_FAIR_GROUP_SCHED
        /* list of leaf cfs_rq on this cpu: */
        struct list_head leaf_cfs_rq_list;
+       struct list_head leaf_rt_rq_list;
 #endif
-       struct rt_rq rt;
 
        /*
         * This is part of a global counter where only the total sum
@@ -430,7 +453,7 @@ struct rq {
        u64 clock, prev_clock_raw;
        s64 clock_max_delta;
 
-       unsigned int clock_warps, clock_overflows;
+       unsigned int clock_warps, clock_overflows, clock_underflows;
        u64 idle_clock;
        unsigned int clock_deep_idle_events;
        u64 tick_timestamp;
@@ -451,6 +474,12 @@ struct rq {
        struct list_head migration_queue;
 #endif
 
+#ifdef CONFIG_SCHED_HRTICK
+       unsigned long hrtick_flags;
+       ktime_t hrtick_expire;
+       struct hrtimer hrtick_timer;
+#endif
+
 #ifdef CONFIG_SCHEDSTATS
        /* latency stats */
        struct sched_info rq_sched_info;
@@ -554,6 +583,23 @@ static void update_rq_clock(struct rq *rq)
 #define task_rq(p)             cpu_rq(task_cpu(p))
 #define cpu_curr(cpu)          (cpu_rq(cpu)->curr)
 
+unsigned long rt_needs_cpu(int cpu)
+{
+       struct rq *rq = cpu_rq(cpu);
+       u64 delta;
+
+       if (!rq->rt_throttled)
+               return 0;
+
+       if (rq->clock > rq->rt_period_expire)
+               return 1;
+
+       delta = rq->rt_period_expire - rq->clock;
+       do_div(delta, NSEC_PER_SEC / HZ);
+
+       return (unsigned long)delta;
+}
+
 /*
  * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
  */
@@ -572,6 +618,8 @@ enum {
        SCHED_FEAT_START_DEBIT          = 4,
        SCHED_FEAT_TREE_AVG             = 8,
        SCHED_FEAT_APPROX_AVG           = 16,
+       SCHED_FEAT_HRTICK               = 32,
+       SCHED_FEAT_DOUBLE_TICK          = 64,
 };
 
 const_debug unsigned int sysctl_sched_features =
@@ -579,7 +627,9 @@ const_debug unsigned int sysctl_sched_features =
                SCHED_FEAT_WAKEUP_PREEMPT       * 1 |
                SCHED_FEAT_START_DEBIT          * 1 |
                SCHED_FEAT_TREE_AVG             * 0 |
-               SCHED_FEAT_APPROX_AVG           * 0;
+               SCHED_FEAT_APPROX_AVG           * 0 |
+               SCHED_FEAT_HRTICK               * 1 |
+               SCHED_FEAT_DOUBLE_TICK          * 0;
 
 #define sched_feat(x) (sysctl_sched_features & SCHED_FEAT_##x)
 
@@ -589,6 +639,21 @@ const_debug unsigned int sysctl_sched_features =
  */
 const_debug unsigned int sysctl_sched_nr_migrate = 32;
 
+/*
+ * period over which we measure -rt task cpu usage in ms.
+ * default: 1s
+ */
+const_debug unsigned int sysctl_sched_rt_period = 1000;
+
+#define SCHED_RT_FRAC_SHIFT    16
+#define SCHED_RT_FRAC          (1UL << SCHED_RT_FRAC_SHIFT)
+
+/*
+ * ratio of time -rt tasks may consume.
+ * default: 95%
+ */
+const_debug unsigned int sysctl_sched_rt_ratio = 62259;
+
 /*
  * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
  * clock constructed from sched_clock():
@@ -781,7 +846,6 @@ void sched_clock_idle_wakeup_event(u64 delta_ns)
        struct rq *rq = cpu_rq(smp_processor_id());
        u64 now = sched_clock();
 
-       touch_softlockup_watchdog();
        rq->idle_clock += delta_ns;
        /*
         * Override the previous timestamp and ignore all
@@ -793,9 +857,177 @@ void sched_clock_idle_wakeup_event(u64 delta_ns)
        rq->prev_clock_raw = now;
        rq->clock += delta_ns;
        spin_unlock(&rq->lock);
+       touch_softlockup_watchdog();
 }
 EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);
 
+static void __resched_task(struct task_struct *p, int tif_bit);
+
+static inline void resched_task(struct task_struct *p)
+{
+       __resched_task(p, TIF_NEED_RESCHED);
+}
+
+#ifdef CONFIG_SCHED_HRTICK
+/*
+ * Use HR-timers to deliver accurate preemption points.
+ *
+ * Its all a bit involved since we cannot program an hrt while holding the
+ * rq->lock. So what we do is store a state in in rq->hrtick_* and ask for a
+ * reschedule event.
+ *
+ * When we get rescheduled we reprogram the hrtick_timer outside of the
+ * rq->lock.
+ */
+static inline void resched_hrt(struct task_struct *p)
+{
+       __resched_task(p, TIF_HRTICK_RESCHED);
+}
+
+static inline void resched_rq(struct rq *rq)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&rq->lock, flags);
+       resched_task(rq->curr);
+       spin_unlock_irqrestore(&rq->lock, flags);
+}
+
+enum {
+       HRTICK_SET,             /* re-programm hrtick_timer */
+       HRTICK_RESET,           /* not a new slice */
+};
+
+/*
+ * Use hrtick when:
+ *  - enabled by features
+ *  - hrtimer is actually high res
+ */
+static inline int hrtick_enabled(struct rq *rq)
+{
+       if (!sched_feat(HRTICK))
+               return 0;
+       return hrtimer_is_hres_active(&rq->hrtick_timer);
+}
+
+/*
+ * Called to set the hrtick timer state.
+ *
+ * called with rq->lock held and irqs disabled
+ */
+static void hrtick_start(struct rq *rq, u64 delay, int reset)
+{
+       assert_spin_locked(&rq->lock);
+
+       /*
+        * preempt at: now + delay
+        */
+       rq->hrtick_expire =
+               ktime_add_ns(rq->hrtick_timer.base->get_time(), delay);
+       /*
+        * indicate we need to program the timer
+        */
+       __set_bit(HRTICK_SET, &rq->hrtick_flags);
+       if (reset)
+               __set_bit(HRTICK_RESET, &rq->hrtick_flags);
+
+       /*
+        * New slices are called from the schedule path and don't need a
+        * forced reschedule.
+        */
+       if (reset)
+               resched_hrt(rq->curr);
+}
+
+static void hrtick_clear(struct rq *rq)
+{
+       if (hrtimer_active(&rq->hrtick_timer))
+               hrtimer_cancel(&rq->hrtick_timer);
+}
+
+/*
+ * Update the timer from the possible pending state.
+ */
+static void hrtick_set(struct rq *rq)
+{
+       ktime_t time;
+       int set, reset;
+       unsigned long flags;
+
+       WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
+
+       spin_lock_irqsave(&rq->lock, flags);
+       set = __test_and_clear_bit(HRTICK_SET, &rq->hrtick_flags);
+       reset = __test_and_clear_bit(HRTICK_RESET, &rq->hrtick_flags);
+       time = rq->hrtick_expire;
+       clear_thread_flag(TIF_HRTICK_RESCHED);
+       spin_unlock_irqrestore(&rq->lock, flags);
+
+       if (set) {
+               hrtimer_start(&rq->hrtick_timer, time, HRTIMER_MODE_ABS);
+               if (reset && !hrtimer_active(&rq->hrtick_timer))
+                       resched_rq(rq);
+       } else
+               hrtick_clear(rq);
+}
+
+/*
+ * High-resolution timer tick.
+ * Runs from hardirq context with interrupts disabled.
+ */
+static enum hrtimer_restart hrtick(struct hrtimer *timer)
+{
+       struct rq *rq = container_of(timer, struct rq, hrtick_timer);
+
+       WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
+
+       spin_lock(&rq->lock);
+       __update_rq_clock(rq);
+       rq->curr->sched_class->task_tick(rq, rq->curr, 1);
+       spin_unlock(&rq->lock);
+
+       return HRTIMER_NORESTART;
+}
+
+static inline void init_rq_hrtick(struct rq *rq)
+{
+       rq->hrtick_flags = 0;
+       hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+       rq->hrtick_timer.function = hrtick;
+       rq->hrtick_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ;
+}
+
+void hrtick_resched(void)
+{
+       struct rq *rq;
+       unsigned long flags;
+
+       if (!test_thread_flag(TIF_HRTICK_RESCHED))
+               return;
+
+       local_irq_save(flags);
+       rq = cpu_rq(smp_processor_id());
+       hrtick_set(rq);
+       local_irq_restore(flags);
+}
+#else
+static inline void hrtick_clear(struct rq *rq)
+{
+}
+
+static inline void hrtick_set(struct rq *rq)
+{
+}
+
+static inline void init_rq_hrtick(struct rq *rq)
+{
+}
+
+void hrtick_resched(void)
+{
+}
+#endif
+
 /*
  * resched_task - mark a task 'to be rescheduled now'.
  *
@@ -809,16 +1041,16 @@ EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);
 #define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG)
 #endif
 
-static void resched_task(struct task_struct *p)
+static void __resched_task(struct task_struct *p, int tif_bit)
 {
        int cpu;
 
        assert_spin_locked(&task_rq(p)->lock);
 
-       if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED)))
+       if (unlikely(test_tsk_thread_flag(p, tif_bit)))
                return;
 
-       set_tsk_thread_flag(p, TIF_NEED_RESCHED);
+       set_tsk_thread_flag(p, tif_bit);
 
        cpu = task_cpu(p);
        if (cpu == smp_processor_id())
@@ -841,10 +1073,10 @@ static void resched_cpu(int cpu)
        spin_unlock_irqrestore(&rq->lock, flags);
 }
 #else
-static inline void resched_task(struct task_struct *p)
+static void __resched_task(struct task_struct *p, int tif_bit)
 {
        assert_spin_locked(&task_rq(p)->lock);
-       set_tsk_need_resched(p);
+       set_tsk_thread_flag(p, tif_bit);
 }
 #endif
 
@@ -1011,12 +1243,12 @@ static int task_hot(struct task_struct *p, u64 now, struct sched_domain *sd);
 
 #define sched_class_highest (&rt_sched_class)
 
-static void inc_nr_running(struct task_struct *p, struct rq *rq)
+static void inc_nr_running(struct rq *rq)
 {
        rq->nr_running++;
 }
 
-static void dec_nr_running(struct task_struct *p, struct rq *rq)
+static void dec_nr_running(struct rq *rq)
 {
        rq->nr_running--;
 }
@@ -1106,11 +1338,11 @@ static int effective_prio(struct task_struct *p)
  */
 static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
 {
-       if (p->state == TASK_UNINTERRUPTIBLE)
+       if (task_contributes_to_load(p))
                rq->nr_uninterruptible--;
 
        enqueue_task(rq, p, wakeup);
-       inc_nr_running(p, rq);
+       inc_nr_running(rq);
 }
 
 /*
@@ -1118,11 +1350,11 @@ static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
  */
 static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep)
 {
-       if (p->state == TASK_UNINTERRUPTIBLE)
+       if (task_contributes_to_load(p))
                rq->nr_uninterruptible++;
 
        dequeue_task(rq, p, sleep);
-       dec_nr_running(p, rq);
+       dec_nr_running(rq);
 }
 
 /**
@@ -1142,7 +1374,7 @@ unsigned long weighted_cpuload(const int cpu)
 
 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
 {
-       set_task_cfs_rq(p, cpu);
+       set_task_rq(p, cpu);
 #ifdef CONFIG_SMP
        /*
         * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
@@ -1649,14 +1881,13 @@ out:
        return success;
 }
 
-int fastcall wake_up_process(struct task_struct *p)
+int wake_up_process(struct task_struct *p)
 {
-       return try_to_wake_up(p, TASK_STOPPED | TASK_TRACED |
-                                TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE, 0);
+       return try_to_wake_up(p, TASK_ALL, 0);
 }
 EXPORT_SYMBOL(wake_up_process);
 
-int fastcall wake_up_state(struct task_struct *p, unsigned int state)
+int wake_up_state(struct task_struct *p, unsigned int state)
 {
        return try_to_wake_up(p, state, 0);
 }
@@ -1743,7 +1974,7 @@ void sched_fork(struct task_struct *p, int clone_flags)
  * that must be done for every newly created context, then puts the task
  * on the runqueue and wakes it.
  */
-void fastcall wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
+void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
 {
        unsigned long flags;
        struct rq *rq;
@@ -1762,7 +1993,7 @@ void fastcall wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
                 * management (if any):
                 */
                p->sched_class->task_new(rq, p);
-               inc_nr_running(p, rq);
+               inc_nr_running(rq);
        }
        check_preempt_curr(rq, p);
 #ifdef CONFIG_SMP
@@ -3492,12 +3723,14 @@ void scheduler_tick(void)
        /*
         * Let rq->clock advance by at least TICK_NSEC:
         */
-       if (unlikely(rq->clock < next_tick))
+       if (unlikely(rq->clock < next_tick)) {
                rq->clock = next_tick;
+               rq->clock_underflows++;
+       }
        rq->tick_timestamp = rq->clock;
        update_cpu_load(rq);
-       if (curr != rq->idle) /* FIXME: needed? */
-               curr->sched_class->task_tick(rq, curr);
+       curr->sched_class->task_tick(rq, curr, 0);
+       update_sched_rt_period(rq);
        spin_unlock(&rq->lock);
 
 #ifdef CONFIG_SMP
@@ -3508,7 +3741,7 @@ void scheduler_tick(void)
 
 #if defined(CONFIG_PREEMPT) && defined(CONFIG_DEBUG_PREEMPT)
 
-void fastcall add_preempt_count(int val)
+void add_preempt_count(int val)
 {
        /*
         * Underflow?
@@ -3524,7 +3757,7 @@ void fastcall add_preempt_count(int val)
 }
 EXPORT_SYMBOL(add_preempt_count);
 
-void fastcall sub_preempt_count(int val)
+void sub_preempt_count(int val)
 {
        /*
         * Underflow?
@@ -3643,6 +3876,8 @@ need_resched_nonpreemptible:
 
        schedule_debug(prev);
 
+       hrtick_clear(rq);
+
        /*
         * Do the rq-clock update outside the rq lock:
         */
@@ -3680,14 +3915,20 @@ need_resched_nonpreemptible:
                ++*switch_count;
 
                context_switch(rq, prev, next); /* unlocks the rq */
+               /*
+                * the context switch might have flipped the stack from under
+                * us, hence refresh the local variables.
+                */
+               cpu = smp_processor_id();
+               rq = cpu_rq(cpu);
        } else
                spin_unlock_irq(&rq->lock);
 
-       if (unlikely(reacquire_kernel_lock(current) < 0)) {
-               cpu = smp_processor_id();
-               rq = cpu_rq(cpu);
+       hrtick_set(rq);
+
+       if (unlikely(reacquire_kernel_lock(current) < 0))
                goto need_resched_nonpreemptible;
-       }
+
        preempt_enable_no_resched();
        if (unlikely(test_thread_flag(TIF_NEED_RESCHED)))
                goto need_resched;
@@ -3703,10 +3944,9 @@ EXPORT_SYMBOL(schedule);
 asmlinkage void __sched preempt_schedule(void)
 {
        struct thread_info *ti = current_thread_info();
-#ifdef CONFIG_PREEMPT_BKL
        struct task_struct *task = current;
        int saved_lock_depth;
-#endif
+
        /*
         * If there is a non-zero preempt_count or interrupts are disabled,
         * we do not want to preempt the current task. Just return..
@@ -3722,14 +3962,10 @@ asmlinkage void __sched preempt_schedule(void)
                 * clear ->lock_depth so that schedule() doesnt
                 * auto-release the semaphore:
                 */
-#ifdef CONFIG_PREEMPT_BKL
                saved_lock_depth = task->lock_depth;
                task->lock_depth = -1;
-#endif
                schedule();
-#ifdef CONFIG_PREEMPT_BKL
                task->lock_depth = saved_lock_depth;
-#endif
                sub_preempt_count(PREEMPT_ACTIVE);
 
                /*
@@ -3750,10 +3986,9 @@ EXPORT_SYMBOL(preempt_schedule);
 asmlinkage void __sched preempt_schedule_irq(void)
 {
        struct thread_info *ti = current_thread_info();
-#ifdef CONFIG_PREEMPT_BKL
        struct task_struct *task = current;
        int saved_lock_depth;
-#endif
+
        /* Catch callers which need to be fixed */
        BUG_ON(ti->preempt_count || !irqs_disabled());
 
@@ -3765,16 +4000,12 @@ asmlinkage void __sched preempt_schedule_irq(void)
                 * clear ->lock_depth so that schedule() doesnt
                 * auto-release the semaphore:
                 */
-#ifdef CONFIG_PREEMPT_BKL
                saved_lock_depth = task->lock_depth;
                task->lock_depth = -1;
-#endif
                local_irq_enable();
                schedule();
                local_irq_disable();
-#ifdef CONFIG_PREEMPT_BKL
                task->lock_depth = saved_lock_depth;
-#endif
                sub_preempt_count(PREEMPT_ACTIVE);
 
                /*
@@ -3824,7 +4055,7 @@ static void __wake_up_common(wait_queue_head_t *q, unsigned int mode,
  * @nr_exclusive: how many wake-one or wake-many threads to wake up
  * @key: is directly passed to the wakeup function
  */
-void fastcall __wake_up(wait_queue_head_t *q, unsigned int mode,
+void __wake_up(wait_queue_head_t *q, unsigned int mode,
                        int nr_exclusive, void *key)
 {
        unsigned long flags;
@@ -3838,7 +4069,7 @@ EXPORT_SYMBOL(__wake_up);
 /*
  * Same as __wake_up but called with the spinlock in wait_queue_head_t held.
  */
-void fastcall __wake_up_locked(wait_queue_head_t *q, unsigned int mode)
+void __wake_up_locked(wait_queue_head_t *q, unsigned int mode)
 {
        __wake_up_common(q, mode, 1, 0, NULL);
 }
@@ -3856,7 +4087,7 @@ void fastcall __wake_up_locked(wait_queue_head_t *q, unsigned int mode)
  *
  * On UP it can prevent extra preemption.
  */
-void fastcall
+void
 __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr_exclusive)
 {
        unsigned long flags;
@@ -3880,8 +4111,7 @@ void complete(struct completion *x)
 
        spin_lock_irqsave(&x->wait.lock, flags);
        x->done++;
-       __wake_up_common(&x->wait, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
-                        1, 0, NULL);
+       __wake_up_common(&x->wait, TASK_NORMAL, 1, 0, NULL);
        spin_unlock_irqrestore(&x->wait.lock, flags);
 }
 EXPORT_SYMBOL(complete);
@@ -3892,8 +4122,7 @@ void complete_all(struct completion *x)
 
        spin_lock_irqsave(&x->wait.lock, flags);
        x->done += UINT_MAX/2;
-       __wake_up_common(&x->wait, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
-                        0, 0, NULL);
+       __wake_up_common(&x->wait, TASK_NORMAL, 0, 0, NULL);
        spin_unlock_irqrestore(&x->wait.lock, flags);
 }
 EXPORT_SYMBOL(complete_all);
@@ -3907,8 +4136,10 @@ do_wait_for_common(struct completion *x, long timeout, int state)
                wait.flags |= WQ_FLAG_EXCLUSIVE;
                __add_wait_queue_tail(&x->wait, &wait);
                do {
-                       if (state == TASK_INTERRUPTIBLE &&
-                           signal_pending(current)) {
+                       if ((state == TASK_INTERRUPTIBLE &&
+                            signal_pending(current)) ||
+                           (state == TASK_KILLABLE &&
+                            fatal_signal_pending(current))) {
                                __remove_wait_queue(&x->wait, &wait);
                                return -ERESTARTSYS;
                        }
@@ -3968,6 +4199,15 @@ wait_for_completion_interruptible_timeout(struct completion *x,
 }
 EXPORT_SYMBOL(wait_for_completion_interruptible_timeout);
 
+int __sched wait_for_completion_killable(struct completion *x)
+{
+       long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_KILLABLE);
+       if (t == -ERESTARTSYS)
+               return t;
+       return 0;
+}
+EXPORT_SYMBOL(wait_for_completion_killable);
+
 static long __sched
 sleep_on_common(wait_queue_head_t *q, int state, long timeout)
 {
@@ -4678,7 +4918,8 @@ static void __cond_resched(void)
        } while (need_resched());
 }
 
-int __sched cond_resched(void)
+#if !defined(CONFIG_PREEMPT) || defined(CONFIG_PREEMPT_VOLUNTARY)
+int __sched _cond_resched(void)
 {
        if (need_resched() && !(preempt_count() & PREEMPT_ACTIVE) &&
                                        system_state == SYSTEM_RUNNING) {
@@ -4687,7 +4928,8 @@ int __sched cond_resched(void)
        }
        return 0;
 }
-EXPORT_SYMBOL(cond_resched);
+EXPORT_SYMBOL(_cond_resched);
+#endif
 
 /*
  * cond_resched_lock() - if a reschedule is pending, drop the given lock,
@@ -4699,19 +4941,15 @@ EXPORT_SYMBOL(cond_resched);
  */
 int cond_resched_lock(spinlock_t *lock)
 {
+       int resched = need_resched() && system_state == SYSTEM_RUNNING;
        int ret = 0;
 
-       if (need_lockbreak(lock)) {
+       if (spin_needbreak(lock) || resched) {
                spin_unlock(lock);
-               cpu_relax();
-               ret = 1;
-               spin_lock(lock);
-       }
-       if (need_resched() && system_state == SYSTEM_RUNNING) {
-               spin_release(&lock->dep_map, 1, _THIS_IP_);
-               _raw_spin_unlock(lock);
-               preempt_enable_no_resched();
-               __cond_resched();
+               if (resched && need_resched())
+                       __cond_resched();
+               else
+                       cpu_relax();
                ret = 1;
                spin_lock(lock);
        }
@@ -4915,8 +5153,7 @@ void sched_show_task(struct task_struct *p)
        printk(KERN_CONT "%5lu %5d %6d\n", free,
                task_pid_nr(p), task_pid_nr(p->real_parent));
 
-       if (state != TASK_RUNNING)
-               show_stack(p, NULL);
+       show_stack(p, NULL);
 }
 
 void show_state_filter(unsigned long state_filter)
@@ -4987,11 +5224,8 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
        spin_unlock_irqrestore(&rq->lock, flags);
 
        /* Set the preempt count _outside_ the spinlocks! */
-#if defined(CONFIG_PREEMPT) && !defined(CONFIG_PREEMPT_BKL)
-       task_thread_info(idle)->preempt_count = (idle->lock_depth >= 0);
-#else
        task_thread_info(idle)->preempt_count = 0;
-#endif
+
        /*
         * The idle tasks have their own, simple scheduling class:
         */
@@ -5076,7 +5310,7 @@ int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
                p->sched_class->set_cpus_allowed(p, &new_mask);
        else {
                p->cpus_allowed = new_mask;
-               p->nr_cpus_allowed = cpus_weight(new_mask);
+               p->rt.nr_cpus_allowed = cpus_weight(new_mask);
        }
 
        /* Can the task run on the task's current CPU? If so, we're done */
@@ -6853,6 +7087,73 @@ static void init_cfs_rq(struct cfs_rq *cfs_rq, struct rq *rq)
        cfs_rq->min_vruntime = (u64)(-(1LL << 20));
 }
 
+static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq)
+{
+       struct rt_prio_array *array;
+       int i;
+
+       array = &rt_rq->active;
+       for (i = 0; i < MAX_RT_PRIO; i++) {
+               INIT_LIST_HEAD(array->queue + i);
+               __clear_bit(i, array->bitmap);
+       }
+       /* delimiter for bitsearch: */
+       __set_bit(MAX_RT_PRIO, array->bitmap);
+
+#if defined CONFIG_SMP || defined CONFIG_FAIR_GROUP_SCHED
+       rt_rq->highest_prio = MAX_RT_PRIO;
+#endif
+#ifdef CONFIG_SMP
+       rt_rq->rt_nr_migratory = 0;
+       rt_rq->overloaded = 0;
+#endif
+
+       rt_rq->rt_time = 0;
+       rt_rq->rt_throttled = 0;
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+       rt_rq->rq = rq;
+#endif
+}
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static void init_tg_cfs_entry(struct rq *rq, struct task_group *tg,
+               struct cfs_rq *cfs_rq, struct sched_entity *se,
+               int cpu, int add)
+{
+       tg->cfs_rq[cpu] = cfs_rq;
+       init_cfs_rq(cfs_rq, rq);
+       cfs_rq->tg = tg;
+       if (add)
+               list_add(&cfs_rq->leaf_cfs_rq_list, &rq->leaf_cfs_rq_list);
+
+       tg->se[cpu] = se;
+       se->cfs_rq = &rq->cfs;
+       se->my_q = cfs_rq;
+       se->load.weight = tg->shares;
+       se->load.inv_weight = div64_64(1ULL<<32, se->load.weight);
+       se->parent = NULL;
+}
+
+static void init_tg_rt_entry(struct rq *rq, struct task_group *tg,
+               struct rt_rq *rt_rq, struct sched_rt_entity *rt_se,
+               int cpu, int add)
+{
+       tg->rt_rq[cpu] = rt_rq;
+       init_rt_rq(rt_rq, rq);
+       rt_rq->tg = tg;
+       rt_rq->rt_se = rt_se;
+       if (add)
+               list_add(&rt_rq->leaf_rt_rq_list, &rq->leaf_rt_rq_list);
+
+       tg->rt_se[cpu] = rt_se;
+       rt_se->rt_rq = &rq->rt;
+       rt_se->my_q = rt_rq;
+       rt_se->parent = NULL;
+       INIT_LIST_HEAD(&rt_se->run_list);
+}
+#endif
+
 void __init sched_init(void)
 {
        int highest_cpu = 0;
@@ -6862,8 +7163,11 @@ void __init sched_init(void)
        init_defrootdomain();
 #endif
 
+#ifdef CONFIG_FAIR_GROUP_SCHED
+       list_add(&init_task_group.list, &task_groups);
+#endif
+
        for_each_possible_cpu(i) {
-               struct rt_prio_array *array;
                struct rq *rq;
 
                rq = cpu_rq(i);
@@ -6872,29 +7176,22 @@ void __init sched_init(void)
                rq->nr_running = 0;
                rq->clock = 1;
                init_cfs_rq(&rq->cfs, rq);
+               init_rt_rq(&rq->rt, rq);
 #ifdef CONFIG_FAIR_GROUP_SCHED
-               INIT_LIST_HEAD(&rq->leaf_cfs_rq_list);
-               {
-                       struct cfs_rq *cfs_rq = &per_cpu(init_cfs_rq, i);
-                       struct sched_entity *se =
-                                        &per_cpu(init_sched_entity, i);
-
-                       init_cfs_rq_p[i] = cfs_rq;
-                       init_cfs_rq(cfs_rq, rq);
-                       cfs_rq->tg = &init_task_group;
-                       list_add(&cfs_rq->leaf_cfs_rq_list,
-                                                        &rq->leaf_cfs_rq_list);
-
-                       init_sched_entity_p[i] = se;
-                       se->cfs_rq = &rq->cfs;
-                       se->my_q = cfs_rq;
-                       se->load.weight = init_task_group_load;
-                       se->load.inv_weight =
-                                div64_64(1ULL<<32, init_task_group_load);
-                       se->parent = NULL;
-               }
                init_task_group.shares = init_task_group_load;
+               INIT_LIST_HEAD(&rq->leaf_cfs_rq_list);
+               init_tg_cfs_entry(rq, &init_task_group,
+                               &per_cpu(init_cfs_rq, i),
+                               &per_cpu(init_sched_entity, i), i, 1);
+
+               init_task_group.rt_ratio = sysctl_sched_rt_ratio; /* XXX */
+               INIT_LIST_HEAD(&rq->leaf_rt_rq_list);
+               init_tg_rt_entry(rq, &init_task_group,
+                               &per_cpu(init_rt_rq, i),
+                               &per_cpu(init_sched_rt_entity, i), i, 1);
 #endif
+               rq->rt_period_expire = 0;
+               rq->rt_throttled = 0;
 
                for (j = 0; j < CPU_LOAD_IDX_MAX; j++)
                        rq->cpu_load[j] = 0;
@@ -6907,20 +7204,11 @@ void __init sched_init(void)
                rq->cpu = i;
                rq->migration_thread = NULL;
                INIT_LIST_HEAD(&rq->migration_queue);
-               rq->rt.highest_prio = MAX_RT_PRIO;
-               rq->rt.overloaded = 0;
                rq_attach_root(rq, &def_root_domain);
 #endif
+               init_rq_hrtick(rq);
                atomic_set(&rq->nr_iowait, 0);
-
-               array = &rq->rt.active;
-               for (j = 0; j < MAX_RT_PRIO; j++) {
-                       INIT_LIST_HEAD(array->queue + j);
-                       __clear_bit(j, array->bitmap);
-               }
                highest_cpu = i;
-               /* delimiter for bitsearch: */
-               __set_bit(MAX_RT_PRIO, array->bitmap);
        }
 
        set_load_weight(&init_task);
@@ -7003,7 +7291,7 @@ void normalize_rt_tasks(void)
        unsigned long flags;
        struct rq *rq;
 
-       read_lock_irq(&tasklist_lock);
+       read_lock_irqsave(&tasklist_lock, flags);
        do_each_thread(g, p) {
                /*
                 * Only normalize user tasks:
@@ -7029,16 +7317,16 @@ void normalize_rt_tasks(void)
                        continue;
                }
 
-               spin_lock_irqsave(&p->pi_lock, flags);
+               spin_lock(&p->pi_lock);
                rq = __task_rq_lock(p);
 
                normalize_task(rq, p);
 
                __task_rq_unlock(rq);
-               spin_unlock_irqrestore(&p->pi_lock, flags);
+               spin_unlock(&p->pi_lock);
        } while_each_thread(g, p);
 
-       read_unlock_irq(&tasklist_lock);
+       read_unlock_irqrestore(&tasklist_lock, flags);
 }
 
 #endif /* CONFIG_MAGIC_SYSRQ */
@@ -7092,7 +7380,7 @@ void set_curr_task(int cpu, struct task_struct *p)
 #ifdef CONFIG_SMP
 /*
  * distribute shares of all task groups among their schedulable entities,
- * to reflect load distrbution across cpus.
+ * to reflect load distribution across cpus.
  */
 static int rebalance_shares(struct sched_domain *sd, int this_cpu)
 {
@@ -7159,7 +7447,7 @@ static int rebalance_shares(struct sched_domain *sd, int this_cpu)
  * sysctl_sched_max_bal_int_shares represents the maximum interval between
  * consecutive calls to rebalance_shares() in the same sched domain.
  *
- * These settings allows for the appropriate tradeoff between accuracy of
+ * These settings allows for the appropriate trade-off between accuracy of
  * fairness and the associated overhead.
  *
  */
@@ -7240,13 +7528,38 @@ static int load_balance_monitor(void *unused)
 }
 #endif /* CONFIG_SMP */
 
+static void free_sched_group(struct task_group *tg)
+{
+       int i;
+
+       for_each_possible_cpu(i) {
+               if (tg->cfs_rq)
+                       kfree(tg->cfs_rq[i]);
+               if (tg->se)
+                       kfree(tg->se[i]);
+               if (tg->rt_rq)
+                       kfree(tg->rt_rq[i]);
+               if (tg->rt_se)
+                       kfree(tg->rt_se[i]);
+       }
+
+       kfree(tg->cfs_rq);
+       kfree(tg->se);
+       kfree(tg->rt_rq);
+       kfree(tg->rt_se);
+       kfree(tg);
+}
+
 /* allocate runqueue etc for a new task group */
 struct task_group *sched_create_group(void)
 {
        struct task_group *tg;
        struct cfs_rq *cfs_rq;
        struct sched_entity *se;
+       struct rt_rq *rt_rq;
+       struct sched_rt_entity *rt_se;
        struct rq *rq;
+       unsigned long flags;
        int i;
 
        tg = kzalloc(sizeof(*tg), GFP_KERNEL);
@@ -7259,100 +7572,90 @@ struct task_group *sched_create_group(void)
        tg->se = kzalloc(sizeof(se) * NR_CPUS, GFP_KERNEL);
        if (!tg->se)
                goto err;
+       tg->rt_rq = kzalloc(sizeof(rt_rq) * NR_CPUS, GFP_KERNEL);
+       if (!tg->rt_rq)
+               goto err;
+       tg->rt_se = kzalloc(sizeof(rt_se) * NR_CPUS, GFP_KERNEL);
+       if (!tg->rt_se)
+               goto err;
+
+       tg->shares = NICE_0_LOAD;
+       tg->rt_ratio = 0; /* XXX */
 
        for_each_possible_cpu(i) {
                rq = cpu_rq(i);
 
-               cfs_rq = kmalloc_node(sizeof(struct cfs_rq), GFP_KERNEL,
-                                                        cpu_to_node(i));
+               cfs_rq = kmalloc_node(sizeof(struct cfs_rq),
+                               GFP_KERNEL|__GFP_ZERO, cpu_to_node(i));
                if (!cfs_rq)
                        goto err;
 
-               se = kmalloc_node(sizeof(struct sched_entity), GFP_KERNEL,
-                                                       cpu_to_node(i));
+               se = kmalloc_node(sizeof(struct sched_entity),
+                               GFP_KERNEL|__GFP_ZERO, cpu_to_node(i));
                if (!se)
                        goto err;
 
-               memset(cfs_rq, 0, sizeof(struct cfs_rq));
-               memset(se, 0, sizeof(struct sched_entity));
+               rt_rq = kmalloc_node(sizeof(struct rt_rq),
+                               GFP_KERNEL|__GFP_ZERO, cpu_to_node(i));
+               if (!rt_rq)
+                       goto err;
 
-               tg->cfs_rq[i] = cfs_rq;
-               init_cfs_rq(cfs_rq, rq);
-               cfs_rq->tg = tg;
+               rt_se = kmalloc_node(sizeof(struct sched_rt_entity),
+                               GFP_KERNEL|__GFP_ZERO, cpu_to_node(i));
+               if (!rt_se)
+                       goto err;
 
-               tg->se[i] = se;
-               se->cfs_rq = &rq->cfs;
-               se->my_q = cfs_rq;
-               se->load.weight = NICE_0_LOAD;
-               se->load.inv_weight = div64_64(1ULL<<32, NICE_0_LOAD);
-               se->parent = NULL;
+               init_tg_cfs_entry(rq, tg, cfs_rq, se, i, 0);
+               init_tg_rt_entry(rq, tg, rt_rq, rt_se, i, 0);
        }
 
-       tg->shares = NICE_0_LOAD;
-
-       lock_task_group_list();
+       spin_lock_irqsave(&task_group_lock, flags);
        for_each_possible_cpu(i) {
                rq = cpu_rq(i);
                cfs_rq = tg->cfs_rq[i];
                list_add_rcu(&cfs_rq->leaf_cfs_rq_list, &rq->leaf_cfs_rq_list);
+               rt_rq = tg->rt_rq[i];
+               list_add_rcu(&rt_rq->leaf_rt_rq_list, &rq->leaf_rt_rq_list);
        }
-       unlock_task_group_list();
+       list_add_rcu(&tg->list, &task_groups);
+       spin_unlock_irqrestore(&task_group_lock, flags);
 
        return tg;
 
 err:
-       for_each_possible_cpu(i) {
-               if (tg->cfs_rq)
-                       kfree(tg->cfs_rq[i]);
-               if (tg->se)
-                       kfree(tg->se[i]);
-       }
-       kfree(tg->cfs_rq);
-       kfree(tg->se);
-       kfree(tg);
-
+       free_sched_group(tg);
        return ERR_PTR(-ENOMEM);
 }
 
 /* rcu callback to free various structures associated with a task group */
-static void free_sched_group(struct rcu_head *rhp)
+static void free_sched_group_rcu(struct rcu_head *rhp)
 {
-       struct task_group *tg = container_of(rhp, struct task_group, rcu);
-       struct cfs_rq *cfs_rq;
-       struct sched_entity *se;
-       int i;
-
        /* now it should be safe to free those cfs_rqs */
-       for_each_possible_cpu(i) {
-               cfs_rq = tg->cfs_rq[i];
-               kfree(cfs_rq);
-
-               se = tg->se[i];
-               kfree(se);
-       }
-
-       kfree(tg->cfs_rq);
-       kfree(tg->se);
-       kfree(tg);
+       free_sched_group(container_of(rhp, struct task_group, rcu));
 }
 
 /* Destroy runqueue etc associated with a task group */
 void sched_destroy_group(struct task_group *tg)
 {
        struct cfs_rq *cfs_rq = NULL;
+       struct rt_rq *rt_rq = NULL;
+       unsigned long flags;
        int i;
 
-       lock_task_group_list();
+       spin_lock_irqsave(&task_group_lock, flags);
        for_each_possible_cpu(i) {
                cfs_rq = tg->cfs_rq[i];
                list_del_rcu(&cfs_rq->leaf_cfs_rq_list);
+               rt_rq = tg->rt_rq[i];
+               list_del_rcu(&rt_rq->leaf_rt_rq_list);
        }
-       unlock_task_group_list();
+       list_del_rcu(&tg->list);
+       spin_unlock_irqrestore(&task_group_lock, flags);
 
        BUG_ON(!cfs_rq);
 
        /* wait for possible concurrent references to cfs_rqs complete */
-       call_rcu(&tg->rcu, free_sched_group);
+       call_rcu(&tg->rcu, free_sched_group_rcu);
 }
 
 /* change task's runqueue when it moves between groups.
@@ -7368,11 +7671,6 @@ void sched_move_task(struct task_struct *tsk)
 
        rq = task_rq_lock(tsk, &flags);
 
-       if (tsk->sched_class != &fair_sched_class) {
-               set_task_cfs_rq(tsk, task_cpu(tsk));
-               goto done;
-       }
-
        update_rq_clock(rq);
 
        running = task_current(rq, tsk);
@@ -7384,7 +7682,7 @@ void sched_move_task(struct task_struct *tsk)
                        tsk->sched_class->put_prev_task(rq, tsk);
        }
 
-       set_task_cfs_rq(tsk, task_cpu(tsk));
+       set_task_rq(tsk, task_cpu(tsk));
 
        if (on_rq) {
                if (unlikely(running))
@@ -7392,7 +7690,6 @@ void sched_move_task(struct task_struct *tsk)
                enqueue_task(rq, tsk, 0);
        }
 
-done:
        task_rq_unlock(rq, &flags);
 }
 
@@ -7421,13 +7718,16 @@ static void set_se_shares(struct sched_entity *se, unsigned long shares)
        }
 }
 
+static DEFINE_MUTEX(shares_mutex);
+
 int sched_group_set_shares(struct task_group *tg, unsigned long shares)
 {
        int i;
        struct cfs_rq *cfs_rq;
        struct rq *rq;
+       unsigned long flags;
 
-       lock_task_group_list();
+       mutex_lock(&shares_mutex);
        if (tg->shares == shares)
                goto done;
 
@@ -7439,10 +7739,12 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
         * load_balance_fair) from referring to this group first,
         * by taking it off the rq->leaf_cfs_rq_list on each cpu.
         */
+       spin_lock_irqsave(&task_group_lock, flags);
        for_each_possible_cpu(i) {
                cfs_rq = tg->cfs_rq[i];
                list_del_rcu(&cfs_rq->leaf_cfs_rq_list);
        }
+       spin_unlock_irqrestore(&task_group_lock, flags);
 
        /* wait for any ongoing reference to this group to finish */
        synchronize_sched();
@@ -7462,13 +7764,15 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
         * Enable load balance activity on this group, by inserting it back on
         * each cpu's rq->leaf_cfs_rq_list.
         */
+       spin_lock_irqsave(&task_group_lock, flags);
        for_each_possible_cpu(i) {
                rq = cpu_rq(i);
                cfs_rq = tg->cfs_rq[i];
                list_add_rcu(&cfs_rq->leaf_cfs_rq_list, &rq->leaf_cfs_rq_list);
        }
+       spin_unlock_irqrestore(&task_group_lock, flags);
 done:
-       unlock_task_group_list();
+       mutex_unlock(&shares_mutex);
        return 0;
 }
 
@@ -7477,6 +7781,31 @@ unsigned long sched_group_shares(struct task_group *tg)
        return tg->shares;
 }
 
+/*
+ * Ensure the total rt_ratio <= sysctl_sched_rt_ratio
+ */
+int sched_group_set_rt_ratio(struct task_group *tg, unsigned long rt_ratio)
+{
+       struct task_group *tgi;
+       unsigned long total = 0;
+
+       rcu_read_lock();
+       list_for_each_entry_rcu(tgi, &task_groups, list)
+               total += tgi->rt_ratio;
+       rcu_read_unlock();
+
+       if (total + rt_ratio - tg->rt_ratio > sysctl_sched_rt_ratio)
+               return -EINVAL;
+
+       tg->rt_ratio = rt_ratio;
+       return 0;
+}
+
+unsigned long sched_group_rt_ratio(struct task_group *tg)
+{
+       return tg->rt_ratio;
+}
+
 #endif /* CONFIG_FAIR_GROUP_SCHED */
 
 #ifdef CONFIG_FAIR_CGROUP_SCHED
@@ -7552,12 +7881,30 @@ static u64 cpu_shares_read_uint(struct cgroup *cgrp, struct cftype *cft)
        return (u64) tg->shares;
 }
 
+static int cpu_rt_ratio_write_uint(struct cgroup *cgrp, struct cftype *cftype,
+               u64 rt_ratio_val)
+{
+       return sched_group_set_rt_ratio(cgroup_tg(cgrp), rt_ratio_val);
+}
+
+static u64 cpu_rt_ratio_read_uint(struct cgroup *cgrp, struct cftype *cft)
+{
+       struct task_group *tg = cgroup_tg(cgrp);
+
+       return (u64) tg->rt_ratio;
+}
+
 static struct cftype cpu_files[] = {
        {
                .name = "shares",
                .read_uint = cpu_shares_read_uint,
                .write_uint = cpu_shares_write_uint,
        },
+       {
+               .name = "rt_ratio",
+               .read_uint = cpu_rt_ratio_read_uint,
+               .write_uint = cpu_rt_ratio_write_uint,
+       },
 };
 
 static int cpu_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cont)