From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Report wrong dynamic event type in the command via error_log.
-----
# echo "z hoge" > /sys/kernel/tracing/dynamic_events
sh: write error: Invalid argument
# cat /sys/kernel/tracing/error_log
[ 22.977022] dynevent: error: No matching dynamic event type
Command: z hoge
^
-----
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v2
- Use tracing_log_err() directly to avoid compile error.
- Update error message.
---
kernel/trace/trace_dynevent.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c
index d06854bd32b3..c4dfbc293bae 100644
--- a/kernel/trace/trace_dynevent.c
+++ b/kernel/trace/trace_dynevent.c
@@ -144,9 +144,16 @@ static int create_dyn_event(const char *raw_command)
if (!ret || ret != -ECANCELED)
break;
}
- mutex_unlock(&dyn_event_ops_mutex);
- if (ret == -ECANCELED)
+ if (ret == -ECANCELED) {
+ static const char *err_msg[] = {"No matching dynamic event type"};
+
+ /* Wrong dynamic event. Leave an error message. */
+ tracing_log_err(NULL, "dynevent", raw_command, err_msg,
+ 0, 0);
ret = -EINVAL;
+ }
+
+ mutex_unlock(&dyn_event_ops_mutex);
return ret;
}