1 files changed, 46 insertions, 2 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 5e6f5f5750a3..8bd2f12810e3 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -186,12 +186,37 @@ int sysctl_sched_rt_runtime = 950000;
 
 void raw_spin_rq_lock_nested(struct rq *rq, int subclass)
 {
-	raw_spin_lock_nested(rq_lockp(rq), subclass);
+	raw_spinlock_t *lock;
+
+	if (sched_core_disabled()) {
+		raw_spin_lock_nested(&rq->__lock, subclass);
+		return;
+	}
+
+	for (;;) {
+		lock = rq_lockp(rq);
+		raw_spin_lock_nested(lock, subclass);
+		if (likely(lock == rq_lockp(rq)))
+			return;
+		raw_spin_unlock(lock);
+	}
 }
 
 bool raw_spin_rq_trylock(struct rq *rq)
 {
-	return raw_spin_trylock(rq_lockp(rq));
+	raw_spinlock_t *lock;
+	bool ret;
+
+	if (sched_core_disabled())
+		return raw_spin_trylock(&rq->__lock);
+
+	for (;;) {
+		lock = rq_lockp(rq);
+		ret = raw_spin_trylock(lock);
+		if (!ret || (likely(lock == rq_lockp(rq))))
+			return ret;
+		raw_spin_unlock(lock);
+	}
 }
 
 void raw_spin_rq_unlock(struct rq *rq)
@@ -199,6 +224,25 @@ void raw_spin_rq_unlock(struct rq *rq)
 	raw_spin_unlock(rq_lockp(rq));
 }
 
+#ifdef CONFIG_SMP
+/*
+ * double_rq_lock - safely lock two runqueues
+ */
+void double_rq_lock(struct rq *rq1, struct rq *rq2)
+{
+	lockdep_assert_irqs_disabled();
+
+	if (rq_order_less(rq2, rq1))
+		swap(rq1, rq2);
+
+	raw_spin_rq_lock(rq1);
+	if (rq_lockp(rq1) == rq_lockp(rq2))
+		return;
+
+	raw_spin_rq_lock_nested(rq2, SINGLE_DEPTH_NESTING);
+}
+#endif
+
 /*
  * __task_rq_lock - lock the rq @p resides on.
  */