tracing: Rename trace_event_mutex to trace_event_sem

trace_event_mutex is an rw semaphore now, not a mutex, change the name.

Link: http://lkml.kernel.org/r/513D843B.40109@huawei.com

Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
[ Forward ported to my new code ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

kernel/trace/trace_events.c

@@ -1584,7 +1584,7 @@ int trace_add_event_call(struct ftrace_event_call *call)
 }
 
 /*
- * Must be called under locking both of event_mutex and trace_event_mutex.
+ * Must be called under locking both of event_mutex and trace_event_sem.
  */
 static void __trace_remove_event_call(struct ftrace_event_call *call)
 {
@@ -1597,9 +1597,9 @@ static void __trace_remove_event_call(struct ftrace_event_call *call)
 void trace_remove_event_call(struct ftrace_event_call *call)
 {
 	mutex_lock(&event_mutex);
-	down_write(&trace_event_mutex);
+	down_write(&trace_event_sem);
 	__trace_remove_event_call(call);
-	up_write(&trace_event_mutex);
+	up_write(&trace_event_sem);
 	mutex_unlock(&event_mutex);
 }
 
@@ -1707,7 +1707,7 @@ static void trace_module_remove_events(struct module *mod)
 	struct ftrace_event_call *call, *p;
 	bool clear_trace = false;
 
-	down_write(&trace_event_mutex);
+	down_write(&trace_event_sem);
 	list_for_each_entry_safe(call, p, &ftrace_events, list) {
 		if (call->mod == mod) {
 			if (call->flags & TRACE_EVENT_FL_WAS_ENABLED)
@@ -1725,7 +1725,7 @@ static void trace_module_remove_events(struct module *mod)
 		list_del(&file_ops->list);
 		kfree(file_ops);
 	}
-	up_write(&trace_event_mutex);
+	up_write(&trace_event_sem);
 
 	/*
 	 * It is safest to reset the ring buffer if the module being unloaded
@@ -2262,9 +2262,9 @@ int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr)
 	if (ret)
 		goto out_unlock;
 
-	down_write(&trace_event_mutex);
+	down_write(&trace_event_sem);
 	__trace_add_event_dirs(tr);
-	up_write(&trace_event_mutex);
+	up_write(&trace_event_sem);
 
  out_unlock:
 	mutex_unlock(&event_mutex);
@@ -2287,9 +2287,9 @@ early_event_add_tracer(struct dentry *parent, struct trace_array *tr)
 	if (ret)
 		goto out_unlock;
 
-	down_write(&trace_event_mutex);
+	down_write(&trace_event_sem);
 	__trace_early_add_event_dirs(tr);
-	up_write(&trace_event_mutex);
+	up_write(&trace_event_sem);
 
  out_unlock:
 	mutex_unlock(&event_mutex);
@@ -2304,10 +2304,10 @@ int event_trace_del_tracer(struct trace_array *tr)
 
 	mutex_lock(&event_mutex);
 
-	down_write(&trace_event_mutex);
+	down_write(&trace_event_sem);
 	__trace_remove_event_dirs(tr);
 	debugfs_remove_recursive(tr->event_dir);
-	up_write(&trace_event_mutex);
+	up_write(&trace_event_sem);
 
 	tr->event_dir = NULL;
 

kernel/trace/trace_output.c

@@ -14,7 +14,7 @@
 /* must be a power of 2 */
 #define EVENT_HASHSIZE	128
 
-DECLARE_RWSEM(trace_event_mutex);
+DECLARE_RWSEM(trace_event_sem);
 
 static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
 
@@ -826,12 +826,12 @@ static int trace_search_list(struct list_head **list)
 
 void trace_event_read_lock(void)
 {
-	down_read(&trace_event_mutex);
+	down_read(&trace_event_sem);
 }
 
 void trace_event_read_unlock(void)
 {
-	up_read(&trace_event_mutex);
+	up_read(&trace_event_sem);
 }
 
 /**
@@ -854,7 +854,7 @@ int register_ftrace_event(struct trace_event *event)
 	unsigned key;
 	int ret = 0;
 
-	down_write(&trace_event_mutex);
+	down_write(&trace_event_sem);
 
 	if (WARN_ON(!event))
 		goto out;
@@ -909,14 +909,14 @@ int register_ftrace_event(struct trace_event *event)
 
 	ret = event->type;
  out:
-	up_write(&trace_event_mutex);
+	up_write(&trace_event_sem);
 
 	return ret;
 }
 EXPORT_SYMBOL_GPL(register_ftrace_event);
 
 /*
- * Used by module code with the trace_event_mutex held for write.
+ * Used by module code with the trace_event_sem held for write.
  */
 int __unregister_ftrace_event(struct trace_event *event)
 {
@@ -931,9 +931,9 @@ int __unregister_ftrace_event(struct trace_event *event)
  */
 int unregister_ftrace_event(struct trace_event *event)
 {
-	down_write(&trace_event_mutex);
+	down_write(&trace_event_sem);
 	__unregister_ftrace_event(event);
-	up_write(&trace_event_mutex);
+	up_write(&trace_event_sem);
 
 	return 0;
 }

kernel/trace/trace_output.h

@@ -33,7 +33,7 @@ trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry);
 
 /* used by module unregistering */
 extern int __unregister_ftrace_event(struct trace_event *event);
-extern struct rw_semaphore trace_event_mutex;
+extern struct rw_semaphore trace_event_sem;
 
 #define MAX_MEMHEX_BYTES	8
 #define HEX_CHARS		(MAX_MEMHEX_BYTES*2 + 1)