tracing: Add WARN_ON_ONCE when returned value is negative

ret is assigned return value of event_hist_trigger_func, but the value
is unused. It is better to warn when returned value is negative,
rather than just ignoring it.

Link: https://lkml.kernel.org/r/20210529061423.GA103954@hyeyoo

Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Hyeonggon Yoo 2021-05-29 15:14:23 +09:00 committed by Steven Rostedt (VMware)
parent 099dcc1801
commit 6c610dba6e

View file

@ -5232,6 +5232,7 @@ static void unregister_field_var_hists(struct hist_trigger_data *hist_data)
cmd = hist_data->field_var_hists[i]->cmd;
ret = event_hist_trigger_func(&trigger_hist_cmd, file,
"!hist", "hist", cmd);
WARN_ON_ONCE(ret < 0);
}
}