Re: [Qemu-devel] [PATCH v4 0/7] trace: Generic event state description

[Lluís Vilanova]

Stefan Hajnoczi writes:

> On Mon, Jun 11, 2012 at 12:12 PM, Lluís Vilanova <address@hidden> wrote:
>> Stefan Hajnoczi writes:
>> 
>>> On Tue, May 8, 2012 at 3:38 PM, Lluís Vilanova <address@hidden> wrote:
>>>> Provides a generic event state description and a more detailed event 
>>>> control and
>>>> query interface.
>>>> 
>>>> Signed-off-by: Lluís Vilanova <address@hidden>
>>>> ---
>> [...]
>>> What is the point of sstate vs dstate?  It seems the dynamic state is
>>> what can be toggled and sstate is the "disable" keyword.  Why have
>>> sstate since there is already a macro?
>> 
>> 'sstate' is there just in case you query the tracing state of an event 
>> through
>> the 'TraceEvent' structure instead of through the corresponding macro.

> If this is not used by a tracer today we should hold off until it's needed.

I double-checked the code for uses of that and it appears to be there just for
the sake of completeness.

Still, I realized I should have added a check in 'trace_event_set_state_dynamic'
and assert that the event is statically enabled (otherwise dynamically enabling
an event that is statically disabled just does not make sense).

Whatever you prefer, although the code is pretty simple.


Lluis

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