[PATCH 14/21] tracing: Add preempt disable for filter self test

[Steven Rostedt]

From: Steven Rostedt <srostedt@xxxxxxxxxx>

The self testing for event filters does not really need preemption
disabled as there are no races at the time of testing, but the functions
it calls uses rcu_dereference_sched() which will complain if preemption
is not disabled.

Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
 kernel/trace/trace_events_filter.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 6a642e2..816d3d0 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -2101,6 +2101,11 @@ static __init int ftrace_test_event_filter(void)
 			break;
 		}
 
+		/*
+		 * The preemption disabling is not really needed for self
+		 * tests, but the rcu dereference will complain without it.
+		 */
+		preempt_disable();
 		if (*d->not_visited)
 			walk_pred_tree(filter->preds, filter->root,
 				       test_walk_pred_cb,
@@ -2108,6 +2113,7 @@ static __init int ftrace_test_event_filter(void)
 
 		test_pred_visited = 0;
 		err = filter_match_preds(filter, &d->rec);
+		preempt_enable();
 
 		__free_filter(filter);
 
-- 
1.7.5.4


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