X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=kernel%2Fsched_rt.c;h=bd4afa408686e0b67a54bc8ebd8667d3224d4fe7;hp=056cbd2e2a27fea8cb15e76bfc711fe32de03303;hb=dc14192ea9e7bfd6a9e21b08ac712360a5552930;hpb=80f01ca1fce2d5045b98f01989017767339b8700

diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 056cbd2e2a27..bd4afa408686 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -384,7 +384,7 @@ static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
 static int do_balance_runtime(struct rt_rq *rt_rq)
 {
 	struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
-	struct root_domain *rd = cpu_rq(smp_processor_id())->rd;
+	struct root_domain *rd = rq_of_rt_rq(rt_rq)->rd;
 	int i, weight, more = 0;
 	u64 rt_period;
 
@@ -509,6 +509,7 @@ balanced:
 		 * runtime - in which case borrowing doesn't make sense.
 		 */
 		rt_rq->rt_runtime = RUNTIME_INF;
+		rt_rq->rt_throttled = 0;
 		raw_spin_unlock(&rt_rq->rt_runtime_lock);
 		raw_spin_unlock(&rt_b->rt_runtime_lock);
 	}
@@ -560,6 +561,9 @@ static int balance_runtime(struct rt_rq *rt_rq)
 {
 	int more = 0;
 
+	if (!sched_feat(RT_RUNTIME_SHARE))
+		return more;
+
 	if (rt_rq->rt_time > rt_rq->rt_runtime) {
 		raw_spin_unlock(&rt_rq->rt_runtime_lock);
 		more = do_balance_runtime(rt_rq);
@@ -584,6 +588,19 @@ static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
 		return 1;
 
 	span = sched_rt_period_mask();
+#ifdef CONFIG_RT_GROUP_SCHED
+	/*
+	 * FIXME: isolated CPUs should really leave the root task group,
+	 * whether they are isolcpus or were isolated via cpusets, lest
+	 * the timer run on a CPU which does not service all runqueues,
+	 * potentially leaving other CPUs indefinitely throttled.  If
+	 * isolation is really required, the user will turn the throttle
+	 * off to kill the perturbations it causes anyway.  Meanwhile,
+	 * this maintains functionality for boot and/or troubleshooting.
+	 */
+	if (rt_b == &root_task_group.rt_bandwidth)
+		span = cpu_online_mask;
+#endif
 	for_each_cpu(i, span) {
 		int enqueue = 0;
 		struct rt_rq *rt_rq = sched_rt_period_rt_rq(rt_b, i);
@@ -716,6 +733,13 @@ inc_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio)
 {
 	struct rq *rq = rq_of_rt_rq(rt_rq);
 
+#ifdef CONFIG_RT_GROUP_SCHED
+	/*
+	 * Change rq's cpupri only if rt_rq is the top queue.
+	 */
+	if (&rq->rt != rt_rq)
+		return;
+#endif
 	if (rq->online && prio < prev_prio)
 		cpupri_set(&rq->rd->cpupri, rq->cpu, prio);
 }
@@ -725,6 +749,13 @@ dec_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio)
 {
 	struct rq *rq = rq_of_rt_rq(rt_rq);
 
+#ifdef CONFIG_RT_GROUP_SCHED
+	/*
+	 * Change rq's cpupri only if rt_rq is the top queue.
+	 */
+	if (&rq->rt != rt_rq)
+		return;
+#endif
 	if (rq->online && rt_rq->highest_prio.curr != prev_prio)
 		cpupri_set(&rq->rd->cpupri, rq->cpu, rt_rq->highest_prio.curr);
 }
@@ -1036,7 +1067,12 @@ select_task_rq_rt(struct task_struct *p, int sd_flag, int flags)
 	    (p->rt.nr_cpus_allowed > 1)) {
 		int target = find_lowest_rq(p);
 
-		if (target != -1)
+		/*
+		 * Don't bother moving it if the destination CPU is
+		 * not running a lower priority task.
+		 */
+		if (target != -1 &&
+		    p->prio < cpu_rq(target)->rt.highest_prio.curr)
 			cpu = target;
 	}
 	rcu_read_unlock();
@@ -1315,6 +1351,16 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
 
 		lowest_rq = cpu_rq(cpu);
 
+		if (lowest_rq->rt.highest_prio.curr <= task->prio) {
+			/*
+			 * Target rq has tasks of equal or higher priority,
+			 * retrying does not release any lock and is unlikely
+			 * to yield a different result.
+			 */
+			lowest_rq = NULL;
+			break;
+		}
+
 		/* if the prio of this runqueue changed, try again */
 		if (double_lock_balance(rq, lowest_rq)) {
 			/*
@@ -1385,6 +1431,11 @@ static int push_rt_task(struct rq *rq)
 	if (!next_task)
 		return 0;
 
+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+       if (unlikely(task_running(rq, next_task)))
+               return 0;
+#endif
+
 retry:
 	if (unlikely(next_task == rq->curr)) {
 		WARN_ON(1);
@@ -1741,7 +1792,11 @@ 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;
@@ -1750,6 +1805,8 @@ static void watchdog(struct rq *rq, struct task_struct *p)
 
 static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
 {
+	struct sched_rt_entity *rt_se = &p->rt;
+
 	update_curr_rt(rq);
 
 	watchdog(rq, p);
@@ -1767,12 +1824,15 @@ static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
 	p->rt.time_slice = DEF_TIMESLICE;
 
 	/*
-	 * Requeue to the end of queue if we are not the only element
-	 * on the queue:
+	 * Requeue to the end of queue if we (and all of our ancestors) are the
+	 * only element on the queue
 	 */
-	if (p->rt.run_list.prev != p->rt.run_list.next) {
-		requeue_task_rt(rq, p, 0);
-		set_tsk_need_resched(p);
+	for_each_sched_rt_entity(rt_se) {
+		if (rt_se->run_list.prev != rt_se->run_list.next) {
+			requeue_task_rt(rq, p, 0);
+			set_tsk_need_resched(p);
+			return;
+		}
 	}
 }