From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner+w=401wt.eu-S1755628AbZHGJdy@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1755628AbZHGJdy (ORCPT <rfc822;w@1wt.eu>);
	Fri, 7 Aug 2009 05:33:54 -0400
Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752709AbZHGJdx
	(ORCPT <rfc822;linux-kernel-outgoing>);
	Fri, 7 Aug 2009 05:33:53 -0400
Received: from [222.73.24.84] ([222.73.24.84]:55712 "EHLO song.cn.fujitsu.com"
	rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP
	id S1751925AbZHGJdw (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Fri, 7 Aug 2009 05:33:52 -0400
Message-ID: <4A7BF5B3.6060202@cn.fujitsu.com>
Date: Fri, 07 Aug 2009 17:36:51 +0800
From: Zhaolei <zhaolei@cn.fujitsu.com>
User-Agent: Thunderbird 2.0.0.6 (Windows/20070728)
MIME-Version: 1.0
To: Li Zefan <lizf@cn.fujitsu.com>
CC: Steven Rostedt <srostedt@redhat.com>, Ingo Molnar <mingo@elte.hu>,
       Frederic Weisbecker <fweisbec@gmail.com>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: Re: [PATCH 2/2] ftrace: Unify effect of writing to trace_options
 and option/*
References: <4A7A4D7B.7010706@cn.fujitsu.com> <4A7A4DBC.6020403@cn.fujitsu.com> <4A7A6470.60305@cn.fujitsu.com>
In-Reply-To: <4A7A6470.60305@cn.fujitsu.com>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Li Zefan wrote:
> Zhaolei wrote:
>> "echo noglobal-clock > trace_options" can be used to change trace
>> clock but "echo 0 > options/global-clock" can't.
>>
>> We can fix it by using set_tracer_flags() in trace_options_core_write().
>>
> 
> Nice catch.
> 
>> Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
>> ---
>>  kernel/trace/trace.c |    5 ++---
>>  1 files changed, 2 insertions(+), 3 deletions(-)
>>
>> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
>> index 464b7bb..2fa2bac 100644
>> --- a/kernel/trace/trace.c
>> +++ b/kernel/trace/trace.c
>> @@ -3893,12 +3893,11 @@ trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt,
>>  
>>  	switch (val) {
>>  	case 0:
>> -		trace_flags &= ~(1 << index);
>> +		set_tracer_flags(1 << index, 0);
>>  		break;
>>  	case 1:
>> -		trace_flags |= 1 << index;
>> +		set_tracer_flags(1 << index, 1);
>>  		break;
>> -
>>  	default:
>>  		return -EINVAL;
>>  	}
> 
> The whole switch statement can be simplied:
> 
> 	if (val != 0 || val != 1)
> 		return -EINVAL;
> 	set_tracer_flags(1 << index, val);

Hello, Li

Thanks.
V2 will send.

Thanks
Zhaolei