5 files changed, 47 insertions, 2 deletions

diff --git a/include/linux/sched/idle.h b/include/linux/sched/idle.h
index 22873d276be6..d73d314d59c6 100644
--- a/include/linux/sched/idle.h
+++ b/include/linux/sched/idle.h
@@ -11,7 +11,11 @@ enum cpu_idle_type {
 	CPU_MAX_IDLE_TYPES
 };
 
+#ifdef CONFIG_SMP
 extern void wake_up_if_idle(int cpu);
+#else
+static inline void wake_up_if_idle(int cpu) { }
+#endif
 
 /*
  * Idle thread specific functions to determine the need_resched
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
index 5561486fddef..aca874d33fe6 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -49,6 +49,35 @@ static inline void mmdrop(struct mm_struct *mm)
 		__mmdrop(mm);
 }
 
+#ifdef CONFIG_PREEMPT_RT
+/*
+ * RCU callback for delayed mm drop. Not strictly RCU, but call_rcu() is
+ * by far the least expensive way to do that.
+ */
+static inline void __mmdrop_delayed(struct rcu_head *rhp)
+{
+	struct mm_struct *mm = container_of(rhp, struct mm_struct, delayed_drop);
+
+	__mmdrop(mm);
+}
+
+/*
+ * Invoked from finish_task_switch(). Delegates the heavy lifting on RT
+ * kernels via RCU.
+ */
+static inline void mmdrop_sched(struct mm_struct *mm)
+{
+	/* Provides a full memory barrier. See mmdrop() */
+	if (atomic_dec_and_test(&mm->mm_count))
+		call_rcu(&mm->delayed_drop, __mmdrop_delayed);
+}
+#else
+static inline void mmdrop_sched(struct mm_struct *mm)
+{
+	mmdrop(mm);
+}
+#endif
+
 /**
  * mmget() - Pin the address space associated with a &struct mm_struct.
  * @mm: The address space to pin.
diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h
index ef02be869cf2..ba88a6987400 100644
--- a/include/linux/sched/task.h
+++ b/include/linux/sched/task.h
@@ -54,7 +54,8 @@ extern asmlinkage void schedule_tail(struct task_struct *prev);
 extern void init_idle(struct task_struct *idle, int cpu);
 
 extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
-extern void sched_post_fork(struct task_struct *p);
+extern void sched_post_fork(struct task_struct *p,
+			    struct kernel_clone_args *kargs);
 extern void sched_dead(struct task_struct *p);
 
 void __noreturn do_task_dead(void);
diff --git a/include/linux/sched/task_stack.h b/include/linux/sched/task_stack.h
index 2413427e439c..d10150587d81 100644
--- a/include/linux/sched/task_stack.h
+++ b/include/linux/sched/task_stack.h
@@ -25,7 +25,11 @@ static inline void *task_stack_page(const struct task_struct *task)
 
 static inline unsigned long *end_of_stack(const struct task_struct *task)
 {
+#ifdef CONFIG_STACK_GROWSUP
+	return (unsigned long *)((unsigned long)task->stack + THREAD_SIZE) - 1;
+#else
 	return task->stack;
+#endif
 }
 
 #elif !defined(__HAVE_THREAD_FUNCTIONS)
diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h
index 8f0f778b7c91..c07bfa2d80f2 100644
--- a/include/linux/sched/topology.h
+++ b/include/linux/sched/topology.h
@@ -42,6 +42,13 @@ static inline int cpu_smt_flags(void)
 }
 #endif
 
+#ifdef CONFIG_SCHED_CLUSTER
+static inline int cpu_cluster_flags(void)
+{
+	return SD_SHARE_PKG_RESOURCES;
+}
+#endif
+
 #ifdef CONFIG_SCHED_MC
 static inline int cpu_core_flags(void)
 {
@@ -98,7 +105,7 @@ struct sched_domain {
 
 	/* idle_balance() stats */
 	u64 max_newidle_lb_cost;
-	unsigned long next_decay_max_lb_cost;
+	unsigned long last_decay_max_lb_cost;
 
 	u64 avg_scan_cost;		/* select_idle_sibling */