---

yaml
---
r: 277244
b: refs/heads/master
c: dff1672
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: facc4e159672b4ed10aa18147bfa187b013c9505
+refs/heads/master: dff1672d9199fffddb58fa7970ccf59005fc35f3

trunk/kernel/rcutree.c

@@ -1403,7 +1403,10 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp)
 		debug_rcu_head_unqueue(list);
 		__rcu_reclaim(rsp->name, list);
 		list = next;
-		if (++count >= bl)
+		/* Stop only if limit reached and CPU has something to do. */
+		if (++count >= bl &&
+		    (need_resched() ||
+		     (!is_idle_task(current) && !rcu_is_callbacks_kthread())))
 			break;
 	}
 

trunk/kernel/rcutree.h

@@ -455,6 +455,7 @@ static void __init __rcu_init_preempt(void);
 static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
 static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
 static void invoke_rcu_callbacks_kthread(void);
+static bool rcu_is_callbacks_kthread(void);
 #ifdef CONFIG_RCU_BOOST
 static void rcu_preempt_do_callbacks(void);
 static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp,

trunk/kernel/rcutree_plugin.h

@@ -1336,6 +1336,15 @@ static void invoke_rcu_callbacks_kthread(void)
 	local_irq_restore(flags);
 }
 
+/*
+ * Is the current CPU running the RCU-callbacks kthread?
+ * Caller must have preemption disabled.
+ */
+static bool rcu_is_callbacks_kthread(void)
+{
+	return __get_cpu_var(rcu_cpu_kthread_task) == current;
+}
+
 /*
  * Set the affinity of the boost kthread.  The CPU-hotplug locks are
  * held, so no one should be messing with the existence of the boost
@@ -1780,6 +1789,11 @@ static void invoke_rcu_callbacks_kthread(void)
 	WARN_ON_ONCE(1);
 }
 
+static bool rcu_is_callbacks_kthread(void)
+{
+	return false;
+}
+
 static void rcu_preempt_boost_start_gp(struct rcu_node *rnp)
 {
 }