tracing/filters: free pred when clearing filters

Impact: fix (small) per trace filter modification memory leak

Free the current pred when clearing the filters via the filter files.
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: =?ISO-8859-1?Q?Fr=E9d=E9ric?= Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1237878851.8339.58.camel@charm-linux>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/trace/trace_events.c

@@ -516,6 +516,7 @@ event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
 
 	if (pred->clear) {
 		filter_free_preds(call);
+		filter_free_pred(pred);
 		return cnt;
 	}
 
@@ -581,6 +582,7 @@ subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
 
 	if (pred->clear) {
 		filter_free_subsystem_preds(system);
+		filter_free_pred(pred);
 		return cnt;
 	}