Re: [PATCH] kselftests: ftrace: limit the executing time by reading from cached trace

[Steven Rostedt]

On Tue, 26 Oct 2021 21:13:31 +0900
Masami Hiramatsu <mhiramat@xxxxxxxxxx> 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