Re: [Qemu-devel] [PATCH v4 4/6] trace: Add per-vCPU tracing states for events with the 'vcpu' property

[Lluís Vilanova]

Stefan Hajnoczi writes:

> On Fri, Jun 17, 2016 at 10:16:25PM +0200, Lluís Vilanova wrote:
>> Stefan Hajnoczi writes:
>> 
>> > On Tue, Jun 14, 2016 at 03:11:12PM +0200, Lluís Vilanova wrote:
>> >> @@ -1116,6 +1117,7 @@ int main(int argc, char **argv)
>> >> gdbserver_start (gdbstub_port);
>> >> gdb_handlesig(cpu, 0);
>> >> }
>> >> +    trace_init_vcpu_events();
>> 
>> > Do vcpu events make sense in *-user builds?  I thought this feature is
>> > only available in *-softmmu.
>> 
>> It's here for completeness, although it's currently useless. AFAIK, QEMU has
>> multiple vCPUs when the user application is multi-threaded, but user QEMU 
>> has no
>> interface to interactively control event states.

> Yes, please drop the *-user changes.  I see no trace_init_*() calls in
> *-user so it won't be useful to call trace_init_vcpu_events().

Actually, I was thinking on extending the *-user command line to accept
something similar to softmmu to control what and where to trace. I guess this
should go onto a separate series (or can I fold it into this one?).

Cheers,
  Lluis