Re: [PATCH v7 09/16] tracing: Add hist trigger snapshot() action test case

Masami Hiramatsu
2018-11-28T02:16:09Z

Hi Tom,

On Tue, 27 Nov 2018 16:53:45 -0600
Tom Zanussi <zanussi@kernel.org> wrote:

> > > +ping $LOCALHOST -c 3
> > > +nice -n 1 ping $LOCALHOST -c 3
> > > +
> > > +echo 0 > /sys/kernel/debug/tracing/events/sched/enable
> >
> > Shouldn't we stop tracing instead of disabling the event?
> >
>
> This is just reversing the enable, so should be fine, but I can stop
> tracing instead if you prefer.

Oops, maybe we have to check the difference between event enabling and
trace enabling.
echo 0 > tracing_on will stop writing ring buffer, but event may continue
to be called. Does this mean hist will be updated? (and I guess preferrable
behavior is to stop hist too, isn't it?)

Thank you,

--
Masami Hiramatsu <mhiramat@kernel.org>