1 files changed, 126 insertions, 72 deletions

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index f232305dcefe..75686c6d4436 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -43,6 +43,28 @@ static inline int on_dl_rq(struct sched_dl_entity *dl_se)
 	return !RB_EMPTY_NODE(&dl_se->rb_node);
 }
 
+#ifdef CONFIG_RT_MUTEXES
+static inline struct sched_dl_entity *pi_of(struct sched_dl_entity *dl_se)
+{
+	return dl_se->pi_se;
+}
+
+static inline bool is_dl_boosted(struct sched_dl_entity *dl_se)
+{
+	return pi_of(dl_se) != dl_se;
+}
+#else
+static inline struct sched_dl_entity *pi_of(struct sched_dl_entity *dl_se)
+{
+	return dl_se;
+}
+
+static inline bool is_dl_boosted(struct sched_dl_entity *dl_se)
+{
+	return false;
+}
+#endif
+
 #ifdef CONFIG_SMP
 static inline struct dl_bw *dl_bw_of(int i)
 {
@@ -97,6 +119,17 @@ static inline unsigned long dl_bw_capacity(int i)
 		return __dl_bw_capacity(i);
 	}
 }
+
+static inline bool dl_bw_visited(int cpu, u64 gen)
+{
+	struct root_domain *rd = cpu_rq(cpu)->rd;
+
+	if (rd->visit_gen == gen)
+		return true;
+
+	rd->visit_gen = gen;
+	return false;
+}
 #else
 static inline struct dl_bw *dl_bw_of(int i)
 {
@@ -112,6 +145,11 @@ static inline unsigned long dl_bw_capacity(int i)
 {
 	return SCHED_CAPACITY_SCALE;
 }
+
+static inline bool dl_bw_visited(int cpu, u64 gen)
+{
+	return false;
+}
 #endif
 
 static inline
@@ -543,7 +581,7 @@ static int push_dl_task(struct rq *rq);
 
 static inline bool need_pull_dl_task(struct rq *rq, struct task_struct *prev)
 {
-	return dl_task(prev);
+	return rq->online && dl_task(prev);
 }
 
 static DEFINE_PER_CPU(struct callback_head, dl_push_head);
@@ -698,7 +736,7 @@ static inline void setup_new_dl_entity(struct sched_dl_entity *dl_se)
 	struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
 	struct rq *rq = rq_of_dl_rq(dl_rq);
 
-	WARN_ON(dl_se->dl_boosted);
+	WARN_ON(is_dl_boosted(dl_se));
 	WARN_ON(dl_time_before(rq_clock(rq), dl_se->deadline));
 
 	/*
@@ -736,21 +774,20 @@ static inline void setup_new_dl_entity(struct sched_dl_entity *dl_se)
  * could happen are, typically, a entity voluntarily trying to overcome its
  * runtime, or it just underestimated it during sched_setattr().
  */
-static void replenish_dl_entity(struct sched_dl_entity *dl_se,
-				struct sched_dl_entity *pi_se)
+static void replenish_dl_entity(struct sched_dl_entity *dl_se)
 {
 	struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
 	struct rq *rq = rq_of_dl_rq(dl_rq);
 
-	BUG_ON(pi_se->dl_runtime <= 0);
+	BUG_ON(pi_of(dl_se)->dl_runtime <= 0);
 
 	/*
 	 * This could be the case for a !-dl task that is boosted.
 	 * Just go with full inherited parameters.
 	 */
 	if (dl_se->dl_deadline == 0) {
-		dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline;
-		dl_se->runtime = pi_se->dl_runtime;
+		dl_se->deadline = rq_clock(rq) + pi_of(dl_se)->dl_deadline;
+		dl_se->runtime = pi_of(dl_se)->dl_runtime;
 	}
 
 	if (dl_se->dl_yielded && dl_se->runtime > 0)
@@ -763,8 +800,8 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se,
 	 * arbitrary large.
 	 */
 	while (dl_se->runtime <= 0) {
-		dl_se->deadline += pi_se->dl_period;
-		dl_se->runtime += pi_se->dl_runtime;
+		dl_se->deadline += pi_of(dl_se)->dl_period;
+		dl_se->runtime += pi_of(dl_se)->dl_runtime;
 	}
 
 	/*
@@ -778,8 +815,8 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se,
 	 */
 	if (dl_time_before(dl_se->deadline, rq_clock(rq))) {
 		printk_deferred_once("sched: DL replenish lagged too much\n");
-		dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline;
-		dl_se->runtime = pi_se->dl_runtime;
+		dl_se->deadline = rq_clock(rq) + pi_of(dl_se)->dl_deadline;
+		dl_se->runtime = pi_of(dl_se)->dl_runtime;
 	}
 
 	if (dl_se->dl_yielded)
@@ -812,8 +849,7 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se,
  * task with deadline equal to period this is the same of using
  * dl_period instead of dl_deadline in the equation above.
  */
-static bool dl_entity_overflow(struct sched_dl_entity *dl_se,
-			       struct sched_dl_entity *pi_se, u64 t)
+static bool dl_entity_overflow(struct sched_dl_entity *dl_se, u64 t)
 {
 	u64 left, right;
 
@@ -835,9 +871,9 @@ static bool dl_entity_overflow(struct sched_dl_entity *dl_se,
 	 * of anything below microseconds resolution is actually fiction
 	 * (but still we want to give the user that illusion >;).
 	 */
-	left = (pi_se->dl_deadline >> DL_SCALE) * (dl_se->runtime >> DL_SCALE);
+	left = (pi_of(dl_se)->dl_deadline >> DL_SCALE) * (dl_se->runtime >> DL_SCALE);
 	right = ((dl_se->deadline - t) >> DL_SCALE) *
-		(pi_se->dl_runtime >> DL_SCALE);
+		(pi_of(dl_se)->dl_runtime >> DL_SCALE);
 
 	return dl_time_before(right, left);
 }
@@ -922,24 +958,23 @@ static inline bool dl_is_implicit(struct sched_dl_entity *dl_se)
  * Please refer to the comments update_dl_revised_wakeup() function to find
  * more about the Revised CBS rule.
  */
-static void update_dl_entity(struct sched_dl_entity *dl_se,
-			     struct sched_dl_entity *pi_se)
+static void update_dl_entity(struct sched_dl_entity *dl_se)
 {
 	struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
 	struct rq *rq = rq_of_dl_rq(dl_rq);
 
 	if (dl_time_before(dl_se->deadline, rq_clock(rq)) ||
-	    dl_entity_overflow(dl_se, pi_se, rq_clock(rq))) {
+	    dl_entity_overflow(dl_se, rq_clock(rq))) {
 
 		if (unlikely(!dl_is_implicit(dl_se) &&
 			     !dl_time_before(dl_se->deadline, rq_clock(rq)) &&
-			     !dl_se->dl_boosted)){
+			     !is_dl_boosted(dl_se))) {
 			update_dl_revised_wakeup(dl_se, rq);
 			return;
 		}
 
-		dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline;
-		dl_se->runtime = pi_se->dl_runtime;
+		dl_se->deadline = rq_clock(rq) + pi_of(dl_se)->dl_deadline;
+		dl_se->runtime = pi_of(dl_se)->dl_runtime;
 	}
 }
 
@@ -1038,7 +1073,7 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
 	 * The task might have been boosted by someone else and might be in the
 	 * boosting/deboosting path, its not throttled.
 	 */
-	if (dl_se->dl_boosted)
+	if (is_dl_boosted(dl_se))
 		goto unlock;
 
 	/*
@@ -1066,7 +1101,7 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
 	 * but do not enqueue -- wait for our wakeup to do that.
 	 */
 	if (!task_on_rq_queued(p)) {
-		replenish_dl_entity(dl_se, dl_se);
+		replenish_dl_entity(dl_se);
 		goto unlock;
 	}
 
@@ -1156,7 +1191,7 @@ static inline void dl_check_constrained_dl(struct sched_dl_entity *dl_se)
 
 	if (dl_time_before(dl_se->deadline, rq_clock(rq)) &&
 	    dl_time_before(rq_clock(rq), dl_next_period(dl_se))) {
-		if (unlikely(dl_se->dl_boosted || !start_dl_timer(p)))
+		if (unlikely(is_dl_boosted(dl_se) || !start_dl_timer(p)))
 			return;
 		dl_se->dl_throttled = 1;
 		if (dl_se->runtime > 0)
@@ -1287,7 +1322,7 @@ throttle:
 			dl_se->dl_overrun = 1;
 
 		__dequeue_task_dl(rq, curr, 0);
-		if (unlikely(dl_se->dl_boosted || !start_dl_timer(curr)))
+		if (unlikely(is_dl_boosted(dl_se) || !start_dl_timer(curr)))
 			enqueue_task_dl(rq, curr, ENQUEUE_REPLENISH);
 
 		if (!is_leftmost(curr, &rq->dl))
@@ -1378,6 +1413,8 @@ static void inc_dl_deadline(struct dl_rq *dl_rq, u64 deadline)
 
 	if (dl_rq->earliest_dl.curr == 0 ||
 	    dl_time_before(deadline, dl_rq->earliest_dl.curr)) {
+		if (dl_rq->earliest_dl.curr == 0)
+			cpupri_set(&rq->rd->cpupri, rq->cpu, CPUPRI_HIGHER);
 		dl_rq->earliest_dl.curr = deadline;
 		cpudl_set(&rq->rd->cpudl, rq->cpu, deadline);
 	}
@@ -1395,6 +1432,7 @@ static void dec_dl_deadline(struct dl_rq *dl_rq, u64 deadline)
 		dl_rq->earliest_dl.curr = 0;
 		dl_rq->earliest_dl.next = 0;
 		cpudl_clear(&rq->rd->cpudl, rq->cpu);
+		cpupri_set(&rq->rd->cpupri, rq->cpu, rq->rt.highest_prio.curr);
 	} else {
 		struct rb_node *leftmost = dl_rq->root.rb_leftmost;
 		struct sched_dl_entity *entry;
@@ -1481,8 +1519,7 @@ static void __dequeue_dl_entity(struct sched_dl_entity *dl_se)
 }
 
 static void
-enqueue_dl_entity(struct sched_dl_entity *dl_se,
-		  struct sched_dl_entity *pi_se, int flags)
+enqueue_dl_entity(struct sched_dl_entity *dl_se, int flags)
 {
 	BUG_ON(on_dl_rq(dl_se));
 
@@ -1493,9 +1530,9 @@ enqueue_dl_entity(struct sched_dl_entity *dl_se,
 	 */
 	if (flags & ENQUEUE_WAKEUP) {
 		task_contending(dl_se, flags);
-		update_dl_entity(dl_se, pi_se);
+		update_dl_entity(dl_se);
 	} else if (flags & ENQUEUE_REPLENISH) {
-		replenish_dl_entity(dl_se, pi_se);
+		replenish_dl_entity(dl_se);
 	} else if ((flags & ENQUEUE_RESTORE) &&
 		  dl_time_before(dl_se->deadline,
 				 rq_clock(rq_of_dl_rq(dl_rq_of_se(dl_se))))) {
@@ -1512,19 +1549,7 @@ static void dequeue_dl_entity(struct sched_dl_entity *dl_se)
 
 static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)
 {
-	struct task_struct *pi_task = rt_mutex_get_top_task(p);
-	struct sched_dl_entity *pi_se = &p->dl;
-
-	/*
-	 * Use the scheduling parameters of the top pi-waiter task if:
-	 * - we have a top pi-waiter which is a SCHED_DEADLINE task AND
-	 * - our dl_boosted is set (i.e. the pi-waiter's (absolute) deadline is
-	 *   smaller than our deadline OR we are a !SCHED_DEADLINE task getting
-	 *   boosted due to a SCHED_DEADLINE pi-waiter).
-	 * Otherwise we keep our runtime and deadline.
-	 */
-	if (pi_task && dl_prio(pi_task->normal_prio) && p->dl.dl_boosted) {
-		pi_se = &pi_task->dl;
+	if (is_dl_boosted(&p->dl)) {
 		/*
 		 * Because of delays in the detection of the overrun of a
 		 * thread's runtime, it might be the case that a thread
@@ -1557,7 +1582,7 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)
 		 * the throttle.
 		 */
 		p->dl.dl_throttled = 0;
-		BUG_ON(!p->dl.dl_boosted || flags != ENQUEUE_REPLENISH);
+		BUG_ON(!is_dl_boosted(&p->dl) || flags != ENQUEUE_REPLENISH);
 		return;
 	}
 
@@ -1594,7 +1619,7 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)
 		return;
 	}
 
-	enqueue_dl_entity(&p->dl, pi_se, flags);
+	enqueue_dl_entity(&p->dl, flags);
 
 	if (!task_current(rq, p) && p->nr_cpus_allowed > 1)
 		enqueue_pushable_dl_task(rq, p);
@@ -1664,13 +1689,13 @@ static void yield_task_dl(struct rq *rq)
 static int find_later_rq(struct task_struct *task);
 
 static int
-select_task_rq_dl(struct task_struct *p, int cpu, int sd_flag, int flags)
+select_task_rq_dl(struct task_struct *p, int cpu, int flags)
 {
 	struct task_struct *curr;
 	bool select_rq;
 	struct rq *rq;
 
-	if (sd_flag != SD_BALANCE_WAKE)
+	if (!(flags & WF_TTWU))
 		goto out;
 
 	rq = cpu_rq(cpu);
@@ -1912,7 +1937,7 @@ static void task_fork_dl(struct task_struct *p)
 static int pick_dl_task(struct rq *rq, struct task_struct *p, int cpu)
 {
 	if (!task_running(rq, p) &&
-	    cpumask_test_cpu(cpu, p->cpus_ptr))
+	    cpumask_test_cpu(cpu, &p->cpus_mask))
 		return 1;
 	return 0;
 }
@@ -2002,8 +2027,8 @@ static int find_later_rq(struct task_struct *task)
 				return this_cpu;
 			}
 
-			best_cpu = cpumask_first_and(later_mask,
-							sched_domain_span(sd));
+			best_cpu = cpumask_any_and_distribute(later_mask,
+							      sched_domain_span(sd));
 			/*
 			 * Last chance: if a CPU being in both later_mask
 			 * and current sd span is valid, that becomes our
@@ -2025,7 +2050,7 @@ static int find_later_rq(struct task_struct *task)
 	if (this_cpu != -1)
 		return this_cpu;
 
-	cpu = cpumask_any(later_mask);
+	cpu = cpumask_any_distribute(later_mask);
 	if (cpu < nr_cpu_ids)
 		return cpu;
 
@@ -2062,7 +2087,7 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
 		/* Retry if something changed. */
 		if (double_lock_balance(rq, later_rq)) {
 			if (unlikely(task_rq(task) != rq ||
-				     !cpumask_test_cpu(later_rq->cpu, task->cpus_ptr) ||
+				     !cpumask_test_cpu(later_rq->cpu, &task->cpus_mask) ||
 				     task_running(rq, task) ||
 				     !dl_task(task) ||
 				     !task_on_rq_queued(task))) {
@@ -2129,6 +2154,9 @@ static int push_dl_task(struct rq *rq)
 		return 0;
 
 retry:
+	if (is_migration_disabled(next_task))
+		return 0;
+
 	if (WARN_ON(next_task == rq->curr))
 		return 0;
 
@@ -2206,7 +2234,7 @@ static void push_dl_tasks(struct rq *rq)
 static void pull_dl_task(struct rq *this_rq)
 {
 	int this_cpu = this_rq->cpu, cpu;
-	struct task_struct *p;
+	struct task_struct *p, *push_task;
 	bool resched = false;
 	struct rq *src_rq;
 	u64 dmin = LONG_MAX;
@@ -2236,6 +2264,7 @@ static void pull_dl_task(struct rq *this_rq)
 			continue;
 
 		/* Might drop this_rq->lock */
+		push_task = NULL;
 		double_lock_balance(this_rq, src_rq);
 
 		/*
@@ -2267,17 +2296,27 @@ static void pull_dl_task(struct rq *this_rq)
 					   src_rq->curr->dl.deadline))
 				goto skip;
 
-			resched = true;
-
-			deactivate_task(src_rq, p, 0);
-			set_task_cpu(p, this_cpu);
-			activate_task(this_rq, p, 0);
-			dmin = p->dl.deadline;
+			if (is_migration_disabled(p)) {
+				push_task = get_push_task(src_rq);
+			} else {
+				deactivate_task(src_rq, p, 0);
+				set_task_cpu(p, this_cpu);
+				activate_task(this_rq, p, 0);
+				dmin = p->dl.deadline;
+				resched = true;
+			}
 
 			/* Is there any other task even earlier? */
 		}
 skip:
 		double_unlock_balance(this_rq, src_rq);
+
+		if (push_task) {
+			raw_spin_unlock(&this_rq->lock);
+			stop_one_cpu_nowait(src_rq->cpu, push_cpu_stop,
+					    push_task, &src_rq->push_work);
+			raw_spin_lock(&this_rq->lock);
+		}
 	}
 
 	if (resched)
@@ -2301,7 +2340,8 @@ static void task_woken_dl(struct rq *rq, struct task_struct *p)
 }
 
 static void set_cpus_allowed_dl(struct task_struct *p,
-				const struct cpumask *new_mask)
+				const struct cpumask *new_mask,
+				u32 flags)
 {
 	struct root_domain *src_rd;
 	struct rq *rq;
@@ -2330,7 +2370,7 @@ static void set_cpus_allowed_dl(struct task_struct *p,
 		raw_spin_unlock(&src_dl_b->lock);
 	}
 
-	set_cpus_allowed_common(p, new_mask);
+	set_cpus_allowed_common(p, new_mask, flags);
 }
 
 /* Assumes rq->lock is held */
@@ -2503,8 +2543,8 @@ static void prio_changed_dl(struct rq *rq, struct task_struct *p,
 	}
 }
 
-const struct sched_class dl_sched_class
-	__section("__dl_sched_class") = {
+DEFINE_SCHED_CLASS(dl) = {
+
 	.enqueue_task		= enqueue_task_dl,
 	.dequeue_task		= dequeue_task_dl,
 	.yield_task		= yield_task_dl,
@@ -2523,6 +2563,7 @@ const struct sched_class dl_sched_class
 	.rq_online              = rq_online_dl,
 	.rq_offline             = rq_offline_dl,
 	.task_woken		= task_woken_dl,
+	.find_lock_rq		= find_lock_later_rq,
 #endif
 
 	.task_tick		= task_tick_dl,
@@ -2535,33 +2576,39 @@ const struct sched_class dl_sched_class
 	.update_curr		= update_curr_dl,
 };
 
+/* Used for dl_bw check and update, used under sched_rt_handler()::mutex */
+static u64 dl_generation;
+
 int sched_dl_global_validate(void)
 {
 	u64 runtime = global_rt_runtime();
 	u64 period = global_rt_period();
 	u64 new_bw = to_ratio(period, runtime);
+	u64 gen = ++dl_generation;
 	struct dl_bw *dl_b;
-	int cpu, ret = 0;
+	int cpu, cpus, ret = 0;
 	unsigned long flags;
 
 	/*
 	 * Here we want to check the bandwidth not being set to some
 	 * value smaller than the currently allocated bandwidth in
 	 * any of the root_domains.
-	 *
-	 * FIXME: Cycling on all the CPUs is overdoing, but simpler than
-	 * cycling on root_domains... Discussion on different/better
-	 * solutions is welcome!
 	 */
 	for_each_possible_cpu(cpu) {
 		rcu_read_lock_sched();
+
+		if (dl_bw_visited(cpu, gen))
+			goto next;
+
 		dl_b = dl_bw_of(cpu);
+		cpus = dl_bw_cpus(cpu);
 
 		raw_spin_lock_irqsave(&dl_b->lock, flags);
-		if (new_bw < dl_b->total_bw)
+		if (new_bw * cpus < dl_b->total_bw)
 			ret = -EBUSY;
 		raw_spin_unlock_irqrestore(&dl_b->lock, flags);
 
+next:
 		rcu_read_unlock_sched();
 
 		if (ret)
@@ -2587,6 +2634,7 @@ static void init_dl_rq_bw_ratio(struct dl_rq *dl_rq)
 void sched_dl_do_global(void)
 {
 	u64 new_bw = -1;
+	u64 gen = ++dl_generation;
 	struct dl_bw *dl_b;
 	int cpu;
 	unsigned long flags;
@@ -2597,11 +2645,14 @@ void sched_dl_do_global(void)
 	if (global_rt_runtime() != RUNTIME_INF)
 		new_bw = to_ratio(global_rt_period(), global_rt_runtime());
 
-	/*
-	 * FIXME: As above...
-	 */
 	for_each_possible_cpu(cpu) {
 		rcu_read_lock_sched();
+
+		if (dl_bw_visited(cpu, gen)) {
+			rcu_read_unlock_sched();
+			continue;
+		}
+
 		dl_b = dl_bw_of(cpu);
 
 		raw_spin_lock_irqsave(&dl_b->lock, flags);
@@ -2787,11 +2838,14 @@ void __dl_clear_params(struct task_struct *p)
 	dl_se->dl_bw			= 0;
 	dl_se->dl_density		= 0;
 
-	dl_se->dl_boosted		= 0;
 	dl_se->dl_throttled		= 0;
 	dl_se->dl_yielded		= 0;
 	dl_se->dl_non_contending	= 0;
 	dl_se->dl_overrun		= 0;
+
+#ifdef CONFIG_RT_MUTEXES
+	dl_se->pi_se			= dl_se;
+#endif
 }
 
 bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr)