---

yaml
---
r: 302754
b: refs/heads/master
c: 37e377d
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9dd8fb16c36178df2066387d2abd44d8b4dca8c8
+refs/heads/master: 37e377d2823e03528cb64f435d7c0e30b1c668eb

trunk/arch/um/drivers/mconsole_kern.c

@@ -705,7 +705,6 @@ static void stack_proc(void *arg)
 	struct task_struct *from = current, *to = arg;
 
 	to->thread.saved_task = from;
-	rcu_switch_from(from);
 	switch_to(from, to, from);
 }
 

trunk/include/linux/rcupdate.h

@@ -184,14 +184,12 @@ static inline int rcu_preempt_depth(void)
 /* Internal to kernel */
 extern void rcu_sched_qs(int cpu);
 extern void rcu_bh_qs(int cpu);
-extern void rcu_preempt_note_context_switch(void);
 extern void rcu_check_callbacks(int cpu, int user);
 struct notifier_block;
 extern void rcu_idle_enter(void);
 extern void rcu_idle_exit(void);
 extern void rcu_irq_enter(void);
 extern void rcu_irq_exit(void);
-extern void exit_rcu(void);
 
 /**
  * RCU_NONIDLE - Indicate idle-loop code that needs RCU readers

trunk/include/linux/rcutiny.h

@@ -87,13 +87,23 @@ static inline void kfree_call_rcu(struct rcu_head *head,
 
 #ifdef CONFIG_TINY_RCU
 
+static inline void rcu_preempt_note_context_switch(void)
+{
+}
+
+static inline void exit_rcu(void)
+{
+}
+
 static inline int rcu_needs_cpu(int cpu)
 {
 	return 0;
 }
 
 #else /* #ifdef CONFIG_TINY_RCU */
 
+void rcu_preempt_note_context_switch(void);
+extern void exit_rcu(void);
 int rcu_preempt_needs_cpu(void);
 
 static inline int rcu_needs_cpu(int cpu)
@@ -106,6 +116,7 @@ static inline int rcu_needs_cpu(int cpu)
 static inline void rcu_note_context_switch(int cpu)
 {
 	rcu_sched_qs(cpu);
+	rcu_preempt_note_context_switch();
 }
 
 /*

trunk/include/linux/rcutree.h

@@ -45,6 +45,18 @@ static inline void rcu_virt_note_context_switch(int cpu)
 	rcu_note_context_switch(cpu);
 }
 
+#ifdef CONFIG_TREE_PREEMPT_RCU
+
+extern void exit_rcu(void);
+
+#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+
+static inline void exit_rcu(void)
+{
+}
+
+#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */
+
 extern void synchronize_rcu_bh(void);
 extern void synchronize_sched_expedited(void);
 extern void synchronize_rcu_expedited(void);

trunk/include/linux/sched.h

@@ -1905,22 +1905,12 @@ static inline void rcu_copy_process(struct task_struct *p)
 	INIT_LIST_HEAD(&p->rcu_node_entry);
 }
 
-static inline void rcu_switch_from(struct task_struct *prev)
-{
-	if (prev->rcu_read_lock_nesting != 0)
-		rcu_preempt_note_context_switch();
-}
-
 #else
 
 static inline void rcu_copy_process(struct task_struct *p)
 {
 }
 
-static inline void rcu_switch_from(struct task_struct *prev)
-{
-}
-
 #endif
 
 #ifdef CONFIG_SMP

trunk/kernel/rcupdate.c

@@ -51,34 +51,6 @@
 
 #include "rcu.h"
 
-#ifdef CONFIG_PREEMPT_RCU
-
-/*
- * Check for a task exiting while in a preemptible-RCU read-side
- * critical section, clean up if so.  No need to issue warnings,
- * as debug_check_no_locks_held() already does this if lockdep
- * is enabled.
- */
-void exit_rcu(void)
-{
-	struct task_struct *t = current;
-
-	if (likely(list_empty(&current->rcu_node_entry)))
-		return;
-	t->rcu_read_lock_nesting = 1;
-	barrier();
-	t->rcu_read_unlock_special = RCU_READ_UNLOCK_BLOCKED;
-	__rcu_read_unlock();
-}
-
-#else /* #ifdef CONFIG_PREEMPT_RCU */
-
-void exit_rcu(void)
-{
-}
-
-#endif /* #else #ifdef CONFIG_PREEMPT_RCU */
-
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 static struct lock_class_key rcu_lock_key;
 struct lockdep_map rcu_lock_map =

trunk/kernel/rcutiny_plugin.h

@@ -851,6 +851,22 @@ int rcu_preempt_needs_cpu(void)
 	return rcu_preempt_ctrlblk.rcb.rcucblist != NULL;
 }
 
+/*
+ * Check for a task exiting while in a preemptible -RCU read-side
+ * critical section, clean up if so.  No need to issue warnings,
+ * as debug_check_no_locks_held() already does this if lockdep
+ * is enabled.
+ */
+void exit_rcu(void)
+{
+	struct task_struct *t = current;
+
+	if (t->rcu_read_lock_nesting == 0)
+		return;
+	t->rcu_read_lock_nesting = 1;
+	__rcu_read_unlock();
+}
+
 #else /* #ifdef CONFIG_TINY_PREEMPT_RCU */
 
 #ifdef CONFIG_RCU_TRACE

trunk/kernel/rcutorture.c

@@ -1337,6 +1337,7 @@ static void rcutorture_booster_cleanup(int cpu)
 
 	/* This must be outside of the mutex, otherwise deadlock! */
 	kthread_stop(t);
+	boost_tasks[cpu] = NULL;
 }
 
 static int rcutorture_booster_init(int cpu)
@@ -1484,13 +1485,15 @@ static void rcu_torture_onoff_cleanup(void)
 		return;
 	VERBOSE_PRINTK_STRING("Stopping rcu_torture_onoff task");
 	kthread_stop(onoff_task);
+	onoff_task = NULL;
 }
 
 #else /* #ifdef CONFIG_HOTPLUG_CPU */
 
-static void
+static int
 rcu_torture_onoff_init(void)
 {
+	return 0;
 }
 
 static void rcu_torture_onoff_cleanup(void)
@@ -1554,6 +1557,7 @@ static void rcu_torture_stall_cleanup(void)
 		return;
 	VERBOSE_PRINTK_STRING("Stopping rcu_torture_stall_task.");
 	kthread_stop(stall_task);
+	stall_task = NULL;
 }
 
 static int rcutorture_cpu_notify(struct notifier_block *self,
@@ -1665,6 +1669,7 @@ rcu_torture_cleanup(void)
 		VERBOSE_PRINTK_STRING("Stopping rcu_torture_shutdown task");
 		kthread_stop(shutdown_task);
 	}
+	shutdown_task = NULL;
 	rcu_torture_onoff_cleanup();
 
 	/* Wait for all RCU callbacks to fire.  */
@@ -1897,9 +1902,17 @@ rcu_torture_init(void)
 			goto unwind;
 		}
 	}
-	rcu_torture_onoff_init();
+	i = rcu_torture_onoff_init();
+	if (i != 0) {
+		firsterr = i;
+		goto unwind;
+	}
 	register_reboot_notifier(&rcutorture_shutdown_nb);
-	rcu_torture_stall_init();
+	i = rcu_torture_stall_init();
+	if (i != 0) {
+		firsterr = i;
+		goto unwind;
+	}
 	rcutorture_record_test_transition();
 	mutex_unlock(&fullstop_mutex);
 	return 0;

trunk/kernel/rcutree.c

@@ -192,6 +192,7 @@ void rcu_note_context_switch(int cpu)
 {
 	trace_rcu_utilization("Start context switch");
 	rcu_sched_qs(cpu);
+	rcu_preempt_note_context_switch(cpu);
 	trace_rcu_utilization("End context switch");
 }
 EXPORT_SYMBOL_GPL(rcu_note_context_switch);

trunk/kernel/rcutree.h

@@ -423,6 +423,7 @@ DECLARE_PER_CPU(char, rcu_cpu_has_work);
 /* Forward declarations for rcutree_plugin.h */
 static void rcu_bootup_announce(void);
 long rcu_batches_completed(void);
+static void rcu_preempt_note_context_switch(int cpu);
 static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp);
 #ifdef CONFIG_HOTPLUG_CPU
 static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp,

trunk/kernel/rcutree_plugin.h

@@ -153,7 +153,7 @@ static void rcu_preempt_qs(int cpu)
  *
  * Caller must disable preemption.
  */
-void rcu_preempt_note_context_switch(void)
+static void rcu_preempt_note_context_switch(int cpu)
 {
 	struct task_struct *t = current;
 	unsigned long flags;
@@ -164,7 +164,7 @@ void rcu_preempt_note_context_switch(void)
 	    (t->rcu_read_unlock_special & RCU_READ_UNLOCK_BLOCKED) == 0) {
 
 		/* Possibly blocking in an RCU read-side critical section. */
-		rdp = __this_cpu_ptr(rcu_preempt_state.rda);
+		rdp = per_cpu_ptr(rcu_preempt_state.rda, cpu);
 		rnp = rdp->mynode;
 		raw_spin_lock_irqsave(&rnp->lock, flags);
 		t->rcu_read_unlock_special |= RCU_READ_UNLOCK_BLOCKED;
@@ -228,7 +228,7 @@ void rcu_preempt_note_context_switch(void)
 	 * means that we continue to block the current grace period.
 	 */
 	local_irq_save(flags);
-	rcu_preempt_qs(smp_processor_id());
+	rcu_preempt_qs(cpu);
 	local_irq_restore(flags);
 }
 
@@ -969,6 +969,22 @@ static void __init __rcu_init_preempt(void)
 	rcu_init_one(&rcu_preempt_state, &rcu_preempt_data);
 }
 
+/*
+ * Check for a task exiting while in a preemptible-RCU read-side
+ * critical section, clean up if so.  No need to issue warnings,
+ * as debug_check_no_locks_held() already does this if lockdep
+ * is enabled.
+ */
+void exit_rcu(void)
+{
+	struct task_struct *t = current;
+
+	if (t->rcu_read_lock_nesting == 0)
+		return;
+	t->rcu_read_lock_nesting = 1;
+	__rcu_read_unlock();
+}
+
 #else /* #ifdef CONFIG_TREE_PREEMPT_RCU */
 
 static struct rcu_state *rcu_state = &rcu_sched_state;
@@ -1001,6 +1017,14 @@ void rcu_force_quiescent_state(void)
 }
 EXPORT_SYMBOL_GPL(rcu_force_quiescent_state);
 
+/*
+ * Because preemptible RCU does not exist, we never have to check for
+ * CPUs being in quiescent states.
+ */
+static void rcu_preempt_note_context_switch(int cpu)
+{
+}
+
 /*
  * Because preemptible RCU does not exist, there are never any preempted
  * RCU readers.

trunk/kernel/sched/core.c

@@ -2083,7 +2083,6 @@ context_switch(struct rq *rq, struct task_struct *prev,
 #endif
 
 	/* Here we just switch the register state and the stack. */
-	rcu_switch_from(prev);
 	switch_to(prev, next, prev);
 
 	barrier();