Re: [Qemu-devel] [PATCH v2] trace: Remove 'trace_events_dstate_init'

["Daniel P. Berrange" <berrange@redhat.com>]

On Thu, Aug 11, 2016 at 12:23:05PM +0200, Lluís Vilanova wrote:
> Removes the event state array used for early initialization. Since only
> events with the "vcpu" property need a late initialization fixup,
> threats their initialization specially.
> 
> Assumes that the user won't touch the state of "vcpu" events between
> early and late initialization (e.g., through QMP).
> 
> Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
> ---
>  stubs/trace-control.c  |    5 +++++
>  trace/control-target.c |    9 +++++++++
>  trace/control.c        |   23 ++++++++++-------------
>  trace/control.h        |    3 +++
>  trace/event-internal.h |    1 +
>  5 files changed, 28 insertions(+), 13 deletions(-)
> 
> diff --git a/stubs/trace-control.c b/stubs/trace-control.c
> index fe59836..3740c38 100644
> --- a/stubs/trace-control.c
> +++ b/stubs/trace-control.c
> @@ -11,6 +11,11 @@
>  #include "trace/control.h"
>  
>  
> +void trace_event_set_state_dynamic_init(TraceEvent *ev, bool state)
> +{
> +    trace_event_set_state_dynamic(ev, state);
> +}
> +
>  void trace_event_set_state_dynamic(TraceEvent *ev, bool state)
>  {
>      TraceEventID id;
> diff --git a/trace/control-target.c b/trace/control-target.c
> index 74c029a..4ee3733 100644
> --- a/trace/control-target.c
> +++ b/trace/control-target.c
> @@ -13,6 +13,15 @@
>  #include "translate-all.h"
>  
>  
> +void trace_event_set_state_dynamic_init(TraceEvent *ev, bool state)
> +{
> +    TraceEventID id = trace_event_get_id(ev);
> +    assert(trace_event_get_state_static(ev));
> +    /* Ignore "vcpu" property, since no vCPUs have been created yet */
> +    trace_events_enabled_count += state - trace_events_dstate[id];

This is doing arithmetic on a boolean value

> +    trace_events_dstate[id] = state;

This is assigning a boolean value to an int16_t

>  void trace_event_set_state_dynamic(TraceEvent *ev, bool state)
>  {
>      CPUState *vcpu;

Regards,
Daniel
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