1 files changed, 38 insertions, 120 deletions

diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 4f02b2847357..01970c8e64df 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -7,6 +7,8 @@
 
 #include <linux/slab.h>
 
+int sched_rr_timeslice = RR_TIMESLICE;
+
 static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun);
 
 struct rt_bandwidth def_rt_bandwidth;
@@ -397,20 +399,6 @@ static inline struct task_group *next_task_group(struct task_group *tg)
 		(iter = next_task_group(iter)) &&			\
 		(rt_rq = iter->rt_rq[cpu_of(rq)]);)
 
-static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq)
-{
-	list_add_rcu(&rt_rq->leaf_rt_rq_list,
-			&rq_of_rt_rq(rt_rq)->leaf_rt_rq_list);
-}
-
-static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq)
-{
-	list_del_rcu(&rt_rq->leaf_rt_rq_list);
-}
-
-#define for_each_leaf_rt_rq(rt_rq, rq) \
-	list_for_each_entry_rcu(rt_rq, &rq->leaf_rt_rq_list, leaf_rt_rq_list)
-
 #define for_each_sched_rt_entity(rt_se) \
 	for (; rt_se; rt_se = rt_se->parent)
 
@@ -470,7 +458,7 @@ static int rt_se_boosted(struct sched_rt_entity *rt_se)
 #ifdef CONFIG_SMP
 static inline const struct cpumask *sched_rt_period_mask(void)
 {
-	return cpu_rq(smp_processor_id())->rd->span;
+	return this_rq()->rd->span;
 }
 #else
 static inline const struct cpumask *sched_rt_period_mask(void)
@@ -507,17 +495,6 @@ typedef struct rt_rq *rt_rq_iter_t;
 #define for_each_rt_rq(rt_rq, iter, rq) \
 	for ((void) iter, rt_rq = &rq->rt; rt_rq; rt_rq = NULL)
 
-static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq)
-{
-}
-
-static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq)
-{
-}
-
-#define for_each_leaf_rt_rq(rt_rq, rq) \
-	for (rt_rq = &rq->rt; rt_rq; rt_rq = NULL)
-
 #define for_each_sched_rt_entity(rt_se) \
 	for (; rt_se; rt_se = NULL)
 
@@ -697,15 +674,6 @@ balanced:
 	}
 }
 
-static void disable_runtime(struct rq *rq)
-{
-	unsigned long flags;
-
-	raw_spin_lock_irqsave(&rq->lock, flags);
-	__disable_runtime(rq);
-	raw_spin_unlock_irqrestore(&rq->lock, flags);
-}
-
 static void __enable_runtime(struct rq *rq)
 {
 	rt_rq_iter_t iter;
@@ -730,37 +698,6 @@ static void __enable_runtime(struct rq *rq)
 	}
 }
 
-static void enable_runtime(struct rq *rq)
-{
-	unsigned long flags;
-
-	raw_spin_lock_irqsave(&rq->lock, flags);
-	__enable_runtime(rq);
-	raw_spin_unlock_irqrestore(&rq->lock, flags);
-}
-
-int update_runtime(struct notifier_block *nfb, unsigned long action, void *hcpu)
-{
-	int cpu = (int)(long)hcpu;
-
-	switch (action) {
-	case CPU_DOWN_PREPARE:
-	case CPU_DOWN_PREPARE_FROZEN:
-		disable_runtime(cpu_rq(cpu));
-		return NOTIFY_OK;
-
-	case CPU_DOWN_FAILED:
-	case CPU_DOWN_FAILED_FROZEN:
-	case CPU_ONLINE:
-	case CPU_ONLINE_FROZEN:
-		enable_runtime(cpu_rq(cpu));
-		return NOTIFY_OK;
-
-	default:
-		return NOTIFY_DONE;
-	}
-}
-
 static int balance_runtime(struct rt_rq *rt_rq)
 {
 	int more = 0;
@@ -924,9 +861,9 @@ static void update_curr_rt(struct rq *rq)
 	if (curr->sched_class != &rt_sched_class)
 		return;
 
-	delta_exec = rq->clock_task - curr->se.exec_start;
-	if (unlikely((s64)delta_exec < 0))
-		delta_exec = 0;
+	delta_exec = rq_clock_task(rq) - curr->se.exec_start;
+	if (unlikely((s64)delta_exec <= 0))
+		return;
 
 	schedstat_set(curr->se.statistics.exec_max,
 		      max(curr->se.statistics.exec_max, delta_exec));
@@ -934,7 +871,7 @@ static void update_curr_rt(struct rq *rq)
 	curr->se.sum_exec_runtime += delta_exec;
 	account_group_exec_runtime(curr, delta_exec);
 
-	curr->se.exec_start = rq->clock_task;
+	curr->se.exec_start = rq_clock_task(rq);
 	cpuacct_charge(curr, delta_exec);
 
 	sched_rt_avg_update(rq, delta_exec);
@@ -1104,9 +1041,6 @@ static void __enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head)
 	if (group_rq && (rt_rq_throttled(group_rq) || !group_rq->rt_nr_running))
 		return;
 
-	if (!rt_rq->rt_nr_running)
-		list_add_leaf_rt_rq(rt_rq);
-
 	if (head)
 		list_add(&rt_se->run_list, queue);
 	else
@@ -1126,8 +1060,6 @@ static void __dequeue_rt_entity(struct sched_rt_entity *rt_se)
 		__clear_bit(rt_se_prio(rt_se), array->bitmap);
 
 	dec_rt_tasks(rt_se, rt_rq);
-	if (!rt_rq->rt_nr_running)
-		list_del_leaf_rt_rq(rt_rq);
 }
 
 /*
@@ -1383,7 +1315,7 @@ static struct task_struct *_pick_next_task_rt(struct rq *rq)
 	} while (rt_rq);
 
 	p = rt_task_of(rt_se);
-	p->se.exec_start = rq->clock_task;
+	p->se.exec_start = rq_clock_task(rq);
 
 	return p;
 }
@@ -1427,48 +1359,29 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
 static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
 {
 	if (!task_running(rq, p) &&
-	    (cpu < 0 || cpumask_test_cpu(cpu, tsk_cpus_allowed(p))) &&
-	    (p->nr_cpus_allowed > 1))
+	    cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
 		return 1;
 	return 0;
 }
 
-/* Return the second highest RT task, NULL otherwise */
-static struct task_struct *pick_next_highest_task_rt(struct rq *rq, int cpu)
+/*
+ * Return the highest pushable rq's task, which is suitable to be executed
+ * on the cpu, NULL otherwise
+ */
+static struct task_struct *pick_highest_pushable_task(struct rq *rq, int cpu)
 {
-	struct task_struct *next = NULL;
-	struct sched_rt_entity *rt_se;
-	struct rt_prio_array *array;
-	struct rt_rq *rt_rq;
-	int idx;
-
-	for_each_leaf_rt_rq(rt_rq, rq) {
-		array = &rt_rq->active;
-		idx = sched_find_first_bit(array->bitmap);
-next_idx:
-		if (idx >= MAX_RT_PRIO)
-			continue;
-		if (next && next->prio <= idx)
-			continue;
-		list_for_each_entry(rt_se, array->queue + idx, run_list) {
-			struct task_struct *p;
+	struct plist_head *head = &rq->rt.pushable_tasks;
+	struct task_struct *p;
 
-			if (!rt_entity_is_task(rt_se))
-				continue;
+	if (!has_pushable_tasks(rq))
+		return NULL;
 
-			p = rt_task_of(rt_se);
-			if (pick_rt_task(rq, p, cpu)) {
-				next = p;
-				break;
-			}
-		}
-		if (!next) {
-			idx = find_next_bit(array->bitmap, MAX_RT_PRIO, idx+1);
-			goto next_idx;
-		}
+	plist_for_each_entry(p, head, pushable_tasks) {
+		if (pick_rt_task(rq, p, cpu))
+			return p;
 	}
 
-	return next;
+	return NULL;
 }
 
 static DEFINE_PER_CPU(cpumask_var_t, local_cpu_mask);
@@ -1742,12 +1655,10 @@ static int pull_rt_task(struct rq *this_rq)
 		double_lock_balance(this_rq, src_rq);
 
 		/*
-		 * Are there still pullable RT tasks?
+		 * We can pull only a task, which is pushable
+		 * on its rq, and no others.
 		 */
-		if (src_rq->rt.rt_nr_running <= 1)
-			goto skip;
-
-		p = pick_next_highest_task_rt(src_rq, this_cpu);
+		p = pick_highest_pushable_task(src_rq, this_cpu);
 
 		/*
 		 * Do we have an RT task that preempts
@@ -1889,8 +1800,11 @@ static void switched_from_rt(struct rq *rq, struct task_struct *p)
 	 * we may need to handle the pulling of RT tasks
 	 * now.
 	 */
-	if (p->on_rq && !rq->rt.rt_nr_running)
-		pull_rt_task(rq);
+	if (!p->on_rq || rq->rt.rt_nr_running)
+		return;
+
+	if (pull_rt_task(rq))
+		resched_task(rq->curr);
 }
 
 void init_sched_rt_class(void)
@@ -1985,7 +1899,11 @@ static void watchdog(struct rq *rq, struct task_struct *p)
 	if (soft != RLIM_INFINITY) {
 		unsigned long next;
 
-		p->rt.timeout++;
+		if (p->rt.watchdog_stamp != jiffies) {
+			p->rt.timeout++;
+			p->rt.watchdog_stamp = jiffies;
+		}
+
 		next = DIV_ROUND_UP(min(soft, hard), USEC_PER_SEC/HZ);
 		if (p->rt.timeout > next)
 			p->cputime_expires.sched_exp = p->se.sum_exec_runtime;
@@ -2010,7 +1928,7 @@ static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
 	if (--p->rt.time_slice)
 		return;
 
-	p->rt.time_slice = RR_TIMESLICE;
+	p->rt.time_slice = sched_rr_timeslice;
 
 	/*
 	 * Requeue to the end of queue if we (and all of our ancestors) are the
@@ -2029,7 +1947,7 @@ static void set_curr_task_rt(struct rq *rq)
 {
 	struct task_struct *p = rq->curr;
 
-	p->se.exec_start = rq->clock_task;
+	p->se.exec_start = rq_clock_task(rq);
 
 	/* The running task is never eligible for pushing */
 	dequeue_pushable_task(rq, p);
@@ -2041,7 +1959,7 @@ static unsigned int get_rr_interval_rt(struct rq *rq, struct task_struct *task)
 	 * Time slice is 0 for SCHED_FIFO tasks
 	 */
 	if (task->policy == SCHED_RR)
-		return RR_TIMESLICE;
+		return sched_rr_timeslice;
 	else
 		return 0;
 }