From c422ee2b99920c4e877bbb08aff1bf426bdc3f65 Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt@redhat.com>
Date: Wed, 6 May 2009 21:54:09 -0400
Subject: [PATCH] --- yaml --- r: 146105 b: refs/heads/master c:
 9456f0fa6d3cb944d3b9fc31c9a244e0362c26ea h: refs/heads/master i:   146103:
 b28e5c7f3943dc43035a9dd9bebf4dc567456f49 v: v3

---
 [refs]                            |  2 +-
 trunk/kernel/trace/trace.c        | 10 ++++++++++
 trunk/kernel/trace/trace.h        |  2 ++
 trunk/kernel/trace/trace_events.c |  9 +++++++++
 4 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 8ba6e98b8ea4..e49dd9daa878 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 71e1c8ac42ae4038ddb1367cce7097ab868dc532
+refs/heads/master: 9456f0fa6d3cb944d3b9fc31c9a244e0362c26ea
diff --git a/trunk/kernel/trace/trace.c b/trunk/kernel/trace/trace.c
index 4164a344e72a..dd40d2320346 100644
--- a/trunk/kernel/trace/trace.c
+++ b/trunk/kernel/trace/trace.c
@@ -639,6 +639,16 @@ void tracing_reset_online_cpus(struct trace_array *tr)
 		tracing_reset(tr, cpu);
 }
 
+void tracing_reset_current(int cpu)
+{
+	tracing_reset(&global_trace, cpu);
+}
+
+void tracing_reset_current_online_cpus(void)
+{
+	tracing_reset_online_cpus(&global_trace);
+}
+
 #define SAVED_CMDLINES 128
 #define NO_CMDLINE_MAP UINT_MAX
 static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1];
diff --git a/trunk/kernel/trace/trace.h b/trunk/kernel/trace/trace.h
index 777c6c3a0cde..ba25793ffe67 100644
--- a/trunk/kernel/trace/trace.h
+++ b/trunk/kernel/trace/trace.h
@@ -409,6 +409,8 @@ int tracing_is_enabled(void);
 void trace_wake_up(void);
 void tracing_reset(struct trace_array *tr, int cpu);
 void tracing_reset_online_cpus(struct trace_array *tr);
+void tracing_reset_current(int cpu);
+void tracing_reset_current_online_cpus(void);
 int tracing_open_generic(struct inode *inode, struct file *filp);
 struct dentry *trace_create_file(const char *name,
 				 mode_t mode,
diff --git a/trunk/kernel/trace/trace_events.c b/trunk/kernel/trace/trace_events.c
index 8d579ff23610..6d2c842a0248 100644
--- a/trunk/kernel/trace/trace_events.c
+++ b/trunk/kernel/trace/trace_events.c
@@ -932,9 +932,11 @@ static void trace_module_remove_events(struct module *mod)
 {
 	struct ftrace_module_file_ops *file_ops;
 	struct ftrace_event_call *call, *p;
+	bool found = false;
 
 	list_for_each_entry_safe(call, p, &ftrace_events, list) {
 		if (call->mod == mod) {
+			found = true;
 			if (call->enabled) {
 				call->enabled = 0;
 				call->unregfunc();
@@ -957,6 +959,13 @@ static void trace_module_remove_events(struct module *mod)
 		list_del(&file_ops->list);
 		kfree(file_ops);
 	}
+
+	/*
+	 * It is safest to reset the ring buffer if the module being unloaded
+	 * registered any events.
+	 */
+	if (found)
+		tracing_reset_current_online_cpus();
 }
 
 static int trace_module_notify(struct notifier_block *self,