Re: [Qemu-devel] [PATCH v2 10/11] trace-state: [stderr] add support for dynamically enabling/disabling events

[Stefan Hajnoczi]

On Tue, Apr 26, 2011 at 1:30 PM, Fabien Chouteau <address@hidden> wrote:
> On 04/25/2011 08:10 PM, Paolo Bonzini wrote:
>> On 04/25/2011 12:27 PM, Lluís wrote:
>>> But in any case, I'm still not sure if stderr should have programatic
>>> tracing state controls.
>>
>> Yes, please, stderr is even more useful than simple when you're using it 
>> under gdb.
>
> Agreed, trace control seems really useful with stderr, and we should be able 
> to
> do this in a generic way (shared by simple and stderr backends).

The commonality between stderr and simple is having a set of trace
events with on/off states.  Generating trace.h/trace.c is mostly
common.  Toggling trace event states from the monitor as well as
-trace events=<file> are common.

The simple backend additionally allows setting and flushing the output
file.  It also supports dumping the trace buffer.

Stefan