From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755964AbcECLeo (ORCPT ); Tue, 3 May 2016 07:34:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53641 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755767AbcECLen (ORCPT ); Tue, 3 May 2016 07:34:43 -0400 From: Chunyu Hu To: rostedt@goodmis.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH V2] tracing: Don't display trigger file for events that can't be enabled Date: Tue, 3 May 2016 19:34:34 +0800 Message-Id: <1462275274-3911-1-git-send-email-chuhu@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently register function of the event 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 regisgter function except events/ftrace/function.) can't be enabled at all, and an oops will be hit when setting up trigger for those events, so just not showing them is an easy way to avoid the oops. Signed-off-by: Chunyu Hu --- kernel/trace/trace_events.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index da1eeb6..b2eef30 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -2138,8 +2138,13 @@ event_create_dir(struct dentry *parent, struct trace_event_file *file) trace_create_file("filter", 0644, file->dir, file, &ftrace_event_filter_fops); - 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); #ifdef CONFIG_HIST_TRIGGERS trace_create_file("hist", 0444, file->dir, file, -- 1.8.3.1