Re: [Qemu-devel] [PATCH for-2.8 v1 10/60] trace: remove fixed global event state arrays

[Lluís Vilanova]

Daniel P Berrange writes:
[...]
> diff --git a/scripts/tracetool/format/events_c.py 
> b/scripts/tracetool/format/events_c.py
> index 9203377..bab6404 100644
> --- a/scripts/tracetool/format/events_c.py
> +++ b/scripts/tracetool/format/events_c.py
> @@ -25,7 +25,10 @@ def generate(events, backend):
>          '#include "trace/control.h"',
>          '')
 
> -    out('TraceEvent trace_events[TRACE_EVENT_COUNT] = {')
> +    out('uint16_t dstate[TRACE_EVENT_COUNT];')
> +    out('bool dstate_init[TRACE_EVENT_COUNT];')
> +
> +    out('static TraceEvent trace_events[TRACE_EVENT_COUNT] = {')
 
>      for e in events:
>          if "vcpu" in e.properties:

I'd rather keep them as 'trace_events_dstate' and 'trace_events_dstate_init' if
most references are auto-generated. Or maybe I just missed something.

Also, maybe we should just try to get rid of the dstate_init structure. Only
vcpu events need late initialization, which could be something like:

   trace_events_enabled_count--;
   dstate[ev->id]--;
   trace_event_set_state_dynamic(dstate, ev, true);

Non-vcpu events shouldn't need late initialization.


[...]
> diff --git a/stubs/trace-control.c b/stubs/trace-control.c
> index fe59836..31566c2 100644
> --- a/stubs/trace-control.c
> +++ b/stubs/trace-control.c
> @@ -11,16 +11,12 @@
>  #include "trace/control.h"
 
 
> -void trace_event_set_state_dynamic(TraceEvent *ev, bool state)
> +void trace_event_set_state_dynamic(uint16_t *dstate, TraceEvent *ev, bool 
> state)
>  {
> -    TraceEventID id;
>      assert(trace_event_get_state_static(ev));
> -    id = trace_event_get_id(ev);
> -    trace_events_enabled_count += state - trace_events_dstate[id];
> -    trace_events_dstate[id] = state;
>  }

Should not be empty (here, stub means it's not target code).


Cheers,
  Lluis