Re: [Qemu-devel] [PATCH v2 2/2] trace: add trace_event_get_state_backends()

["Lluís Vilanova" <vilanova@ac.upc.edu>]

Stefan Hajnoczi writes:

> On Mon, Jul 31, 2017 at 06:09:56PM +0300, Lluís Vilanova wrote:
>> Stefan Hajnoczi writes:
>> 
>> > Code that checks dstate is unaware of SystemTap and LTTng UST dstate, so
>> > the following trace event will not fire when solely enabled by SystemTap
>> > or LTTng UST:
>> 
>> >   if (trace_event_get_state(TRACE_MY_EVENT)) {
>> >       str = g_strdup_printf("Expensive string to generate ...",
>> >                             ...);
>> >       trace_my_event(str);
>> >       g_free(str);
>> >   }
>> 
>> I believe this should be trace_event_get_state_backends(). Same applies to the
>> cover letter.

> This instance and the cover letter are both showing the pattern in
> existing code.

> The description "event will not fire" is correct with
> trace_event_get_state().  If I change it to
> trace_event_get_state_backends() then the description is no longer
> correct :).

Woops, I read this too quickly and assumed it was a usage example, sorry :)

Cheers,
  Lluis