[PATCH] Tracepoint use rcu sched

[Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>]

Make tracepoints use rcu sched. (cleanup)

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: Ingo Molnar <mingo@elte.hu>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
---
 kernel/tracepoint.c |   15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

Index: linux-2.6-lttng/kernel/tracepoint.c
===================================================================
--- linux-2.6-lttng.orig/kernel/tracepoint.c	2008-09-30 01:36:26.000000000 -0400
+++ linux-2.6-lttng/kernel/tracepoint.c	2008-09-30 01:37:29.000000000 -0400
@@ -82,10 +82,7 @@ static void tracepoint_entry_free_old(st
 	entry->rcu_pending = 1;
 	/* write rcu_pending before calling the RCU callback */
 	smp_wmb();
-#ifdef CONFIG_PREEMPT_RCU
-	synchronize_sched();	/* Until we have the call_rcu_sched() */
-#endif
-	call_rcu(&entry->rcu, free_old_closure);
+	call_rcu_sched(&entry->rcu, free_old_closure);
 }
 
 static void debug_print_probes(struct tracepoint_entry *entry)
@@ -247,9 +244,9 @@ static int remove_tracepoint(const char 
 	if (e->refcount)
 		return -EBUSY;
 	hlist_del(&e->hlist);
-	/* Make sure the call_rcu has been executed */
+	/* Make sure the call_rcu_sched has been executed */
 	if (e->rcu_pending)
-		rcu_barrier();
+		rcu_barrier_sched();
 	kfree(e);
 	return 0;
 }
@@ -349,11 +346,11 @@ int tracepoint_probe_register(const char
 		}
 	}
 	/*
-	 * If we detect that a call_rcu is pending for this tracepoint,
+	 * If we detect that a call_rcu_sched is pending for this tracepoint,
 	 * make sure it's executed now.
 	 */
 	if (entry->rcu_pending)
-		rcu_barrier();
+		rcu_barrier_sched();
 	old = tracepoint_entry_add_probe(entry, probe);
 	if (IS_ERR(old)) {
 		ret = PTR_ERR(old);
@@ -392,7 +389,7 @@ int tracepoint_probe_unregister(const ch
 	if (!entry)
 		goto end;
 	if (entry->rcu_pending)
-		rcu_barrier();
+		rcu_barrier_sched();
 	old = tracepoint_entry_remove_probe(entry, probe);
 	mutex_unlock(&tracepoints_mutex);
 	tracepoint_update_probes();		/* may update entry */
-- 
Mathieu Desnoyers
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