Merge Linus master into drm-next

The merge is clean, but the arm build fails afterwards,
due to API changes in the regulator tree.

I've included the patch into the merge to fix the build.

Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 66 insertions, 11 deletions

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 3fa8fa6d9403..5e95145088fd 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -69,7 +69,7 @@ void init_dl_bw(struct dl_bw *dl_b)
 	dl_b->total_bw = 0;
 }
 
-void init_dl_rq(struct dl_rq *dl_rq, struct rq *rq)
+void init_dl_rq(struct dl_rq *dl_rq)
 {
 	dl_rq->rb_root = RB_ROOT;
 
@@ -218,6 +218,52 @@ static inline void set_post_schedule(struct rq *rq)
 	rq->post_schedule = has_pushable_dl_tasks(rq);
 }
 
+static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq);
+
+static void dl_task_offline_migration(struct rq *rq, struct task_struct *p)
+{
+	struct rq *later_rq = NULL;
+	bool fallback = false;
+
+	later_rq = find_lock_later_rq(p, rq);
+
+	if (!later_rq) {
+		int cpu;
+
+		/*
+		 * If we cannot preempt any rq, fall back to pick any
+		 * online cpu.
+		 */
+		fallback = true;
+		cpu = cpumask_any_and(cpu_active_mask, tsk_cpus_allowed(p));
+		if (cpu >= nr_cpu_ids) {
+			/*
+			 * Fail to find any suitable cpu.
+			 * The task will never come back!
+			 */
+			BUG_ON(dl_bandwidth_enabled());
+
+			/*
+			 * If admission control is disabled we
+			 * try a little harder to let the task
+			 * run.
+			 */
+			cpu = cpumask_any(cpu_active_mask);
+		}
+		later_rq = cpu_rq(cpu);
+		double_lock_balance(rq, later_rq);
+	}
+
+	deactivate_task(rq, p, 0);
+	set_task_cpu(p, later_rq->cpu);
+	activate_task(later_rq, p, ENQUEUE_REPLENISH);
+
+	if (!fallback)
+		resched_curr(later_rq);
+
+	double_unlock_balance(rq, later_rq);
+}
+
 #else
 
 static inline
@@ -514,7 +560,7 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
 	unsigned long flags;
 	struct rq *rq;
 
-	rq = task_rq_lock(current, &flags);
+	rq = task_rq_lock(p, &flags);
 
 	/*
 	 * We need to take care of several possible races here:
@@ -536,6 +582,17 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
 	sched_clock_tick();
 	update_rq_clock(rq);
 
+#ifdef CONFIG_SMP
+	/*
+	 * If we find that the rq the task was on is no longer
+	 * available, we need to select a new rq.
+	 */
+	if (unlikely(!rq->online)) {
+		dl_task_offline_migration(rq, p);
+		goto unlock;
+	}
+#endif
+
 	/*
 	 * If the throttle happened during sched-out; like:
 	 *
@@ -569,7 +626,7 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
 		push_dl_task(rq);
 #endif
 unlock:
-	task_rq_unlock(rq, current, &flags);
+	task_rq_unlock(rq, p, &flags);
 
 	return HRTIMER_NORESTART;
 }
@@ -914,6 +971,12 @@ static void yield_task_dl(struct rq *rq)
 	}
 	update_rq_clock(rq);
 	update_curr_dl(rq);
+	/*
+	 * Tell update_rq_clock() that we've just updated,
+	 * so we don't do microscopic update in schedule()
+	 * and double the fastpath cost.
+	 */
+	rq_clock_skip_update(rq, true);
 }
 
 #ifdef CONFIG_SMP
@@ -1659,14 +1722,6 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p)
 {
 	int check_resched = 1;
 
-	/*
-	 * If p is throttled, don't consider the possibility
-	 * of preempting rq->curr, the check will be done right
-	 * after its runtime will get replenished.
-	 */
-	if (unlikely(p->dl.dl_throttled))
-		return;
-
 	if (task_on_rq_queued(p) && rq->curr != p) {
 #ifdef CONFIG_SMP
 		if (p->nr_cpus_allowed > 1 && rq->dl.overloaded &&