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Date:   Tue, 26 Oct 2021 09:15:34 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Masami Hiramatsu <mhiramat@kernel.org>
Cc:     Li Zhijian <lizhijian@cn.fujitsu.com>, <mingo@redhat.com>,
        <shuah@kernel.org>, <linux-kselftest@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, Philip Li <philip.li@intel.com>,
        kernel test robot <lkp@intel.com>
Subject: Re: [PATCH] kselftests: ftrace: limit the executing time by reading
 from cached trace
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On Tue, 26 Oct 2021 21:13:31 +0900
Masami Hiramatsu <mhiramat@kernel.org> wrote:

> > > No, since each testcase must be run under the clean state. Would we need to
> > > recover the settings?  
> > 
> > I would at least put it back to the default. If someone runs the tests,
> > it should at least put it back to what it was at boot. Otherwise,
> > someone might run the tests, and then wonder why events are being
> > dropped when they are reading the trace.  
> 
> Umm, we may need to have a knob to reset the ftrace options...
> Can we warn such user that if the ftracetest finds that the current
> value is not the same what it sets?

You mean before we set pause-on-trace, make sure that it was cleared?

That could work too, and then just set everything back to what we expected
it to be at the start.

-- Steve