Reply-To: shuah@kernel.org
Subject: Re: [PATCH] selftests: ftrace: Use md5sum to take less time of
 checking logs
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>,
        linux-kselftest@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
        linux-kernel@vger.kernel.org, Shuah Khan <shuah@kernel.org>,
        Shuah Khan <shuahkh@osg.samsung.com>
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 <8f6497e7-8236-f0e0-0f51-87d691b9df8b@kernel.org>
 <20170628105923.6bdaa9a3@gandalf.local.home>
 <97100897-9bd4-11e0-79a5-faea8ba22a09@kernel.org>
From: Shuah Khan <shuah@kernel.org>
Message-ID: <c83c6357-8836-7a52-84ff-fb66fa2c57f0@kernel.org>
Date: Thu, 29 Jun 2017 14:21:41 -0600
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On 06/28/2017 09:30 AM, Shuah Khan wrote:
> On 06/28/2017 08:59 AM, Steven Rostedt wrote:
>> On Wed, 28 Jun 2017 08:30:24 -0600
>> Shuah Khan <shuah@kernel.org> wrote:
>>
>>> On 06/28/2017 08:17 AM, Steven Rostedt wrote:
>>>> On Tue, 27 Jun 2017 19:28:32 +0900
>>>> Masami Hiramatsu <mhiramat@kernel.org> wrote:
>>>>   
>>>>> Use md5sum so that it takes less time of checking
>>>>> trace logs update. Since busybox tail/cat takes too
>>>>> long time to read the trace log, this uses md5sum
>>>>> to check whether trace log is updated or not.  
>>>>
>>>> How much faster is md5sum? I can see this causing issues in other
>>>> environments.
>>>>
>>>> -- Steve  
>>>
>>> Sorry Steve. I pulled this into linux-ksefltest next. Are you concerned
>>> about any specific environments? I can try this out and see if it is a
>>> problem.
>>
>> Yes please. I should probably do some playing too. I would like to fix
>> that test anyway, as it is one of the longer ones as I do a lot of
>> "paranoid checks". That is, I may go overboard in testing if tracing is
>> off or not, by checking to make sure its off using different tactics.
>>
> 
> Please let me know how your trials go. I have a few things I have to get
> to before I get around to trying this patch.
> 
> thanks,
> -- Shuah

Hi Steve/Masami,

I tested this patch on my test system running 4.12-rc7 and didn't see any
problems. I am going to leave this in the linux-kselftest next for 4.13-rc1.
Please let me if you think I should drop it.

thanks,
-- Shuah