rcu: Move rcu_print_task_exp_stall() to tree_exp.h

Because expedited CPU stall warnings are contained within the
kernel/rcu/tree_exp.h file, rcu_print_task_exp_stall() should live
there too.  This commit carries out the required code motion.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>

diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h
index 4c2a018..7be3e08 100644 (file)
--- a/kernel/rcu/tree_exp.h
+++ b/kernel/rcu/tree_exp.h
@@ -10,6 +10,7 @@
 #include <linux/lockdep.h>
 
 static void rcu_exp_handler(void *unused);
+static int rcu_print_task_exp_stall(struct rcu_node *rnp);
 
 /*
  * Record the start of an expedited grace period.
@@ -670,6 +671,27 @@ static void sync_sched_exp_online_cleanup(int cpu)
 {
 }
 
+/*
+ * Scan the current list of tasks blocked within RCU read-side critical
+ * sections, printing out the tid of each that is blocking the current
+ * expedited grace period.
+ */
+static int rcu_print_task_exp_stall(struct rcu_node *rnp)
+{
+       struct task_struct *t;
+       int ndetected = 0;
+
+       if (!rnp->exp_tasks)
+               return 0;
+       t = list_entry(rnp->exp_tasks->prev,
+                      struct task_struct, rcu_node_entry);
+       list_for_each_entry_continue(t, &rnp->blkd_tasks, rcu_node_entry) {
+               pr_cont(" P%d", t->pid);
+               ndetected++;
+       }
+       return ndetected;
+}
+
 #else /* #ifdef CONFIG_PREEMPT_RCU */
 
 /* Invoked on each online non-idle CPU for expedited quiescent state. */
@@ -709,6 +731,16 @@ static void sync_sched_exp_online_cleanup(int cpu)
        WARN_ON_ONCE(ret);
 }
 
+/*
+ * Because preemptible RCU does not exist, we never have to check for
+ * tasks blocked within RCU read-side critical sections that are
+ * blocking the current expedited grace period.
+ */
+static int rcu_print_task_exp_stall(struct rcu_node *rnp)
+{
+       return 0;
+}
+
 #endif /* #else #ifdef CONFIG_PREEMPT_RCU */
 
 /**

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 7fa3bc4..72519c5 100644 (file)
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -643,27 +643,6 @@ static void rcu_read_unlock_special(struct task_struct *t)
 }
 
 /*
- * Scan the current list of tasks blocked within RCU read-side critical
- * sections, printing out the tid of each that is blocking the current
- * expedited grace period.
- */
-static int rcu_print_task_exp_stall(struct rcu_node *rnp)
-{
-       struct task_struct *t;
-       int ndetected = 0;
-
-       if (!rnp->exp_tasks)
-               return 0;
-       t = list_entry(rnp->exp_tasks->prev,
-                      struct task_struct, rcu_node_entry);
-       list_for_each_entry_continue(t, &rnp->blkd_tasks, rcu_node_entry) {
-               pr_cont(" P%d", t->pid);
-               ndetected++;
-       }
-       return ndetected;
-}
-
-/*
  * Check that the list of blocked tasks for the newly completed grace
  * period is in fact empty.  It is a serious bug to complete a grace
  * period that still has RCU readers blocked!  This function must be
@@ -907,16 +886,6 @@ static bool rcu_preempt_need_deferred_qs(struct task_struct *t)
 static void rcu_preempt_deferred_qs(struct task_struct *t) { }
 
 /*
- * Because preemptible RCU does not exist, we never have to check for
- * tasks blocked within RCU read-side critical sections that are
- * blocking the current expedited grace period.
- */
-static int rcu_print_task_exp_stall(struct rcu_node *rnp)
-{
-       return 0;
-}
-
-/*
  * Because there is no preemptible RCU, there can be no readers blocked,
  * so there is no need to check for blocked tasks.  So check only for
  * bogus qsmask values.