path: root/kernel
diff options
authorChunyu Hu <>2016-05-03 19:34:34 +0800
committerSteven Rostedt <>2016-05-03 12:59:30 -0400
commit854145e0a8e9a05f7366d240e2f99d9c1ca6d6dd (patch)
tree4a66a8bc548b7a5bf8ae0e8890a09cd589af9ab8 /kernel
parent04974df8049fc4240d22759a91e035082ccd18b4 (diff)
tracing: Don't display trigger file for events that can't be enabled
Currently register functions for events will be called through the 'reg' field of event class directly without any check when seting up triggers. Triggers for events that don't support register through debug fs (events under events/ftrace are for trace-cmd to read event format, and most of them don't have a register function except events/ftrace/functionx) can't be enabled at all, and an oops will be hit when setting up trigger for those events, so just not creating them is an easy way to avoid the oops. Link: Cc: # 3.14+ Fixes: 85f2b08268c01 ("tracing: Add basic event trigger framework") Signed-off-by: Chunyu Hu <> Signed-off-by: Steven Rostedt <>
Diffstat (limited to 'kernel')
1 files changed, 7 insertions, 2 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 05ddc0820771..6f965864cc02 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2095,8 +2095,13 @@ event_create_dir(struct dentry *parent, struct trace_event_file *file)
trace_create_file("filter", 0644, file->dir, file,
- trace_create_file("trigger", 0644, file->dir, file,
- &event_trigger_fops);
+ /*
+ * Only event directories that can be enabled should have
+ * triggers.
+ */
+ if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE))
+ trace_create_file("trigger", 0644, file->dir, file,
+ &event_trigger_fops);
trace_create_file("format", 0444, file->dir, call,