Re: trace_exec_tb(tb, pc) does not have cpu index

[Peter Maydell]

On Tue, 22 Aug 2023 at 10:01, Alex Bennée <alex.bennee@linaro.org> wrote:
>
>
> Igor Lesik <lesikigor@meta.com> writes:
>
> > Hi.
> >
> > I am wondering why trace events like trace_exec_tb(tb, pc) do not have
> > cpu index, how to make sense of the trace in case of multiple vCPUs?
> > I have changed it to trace_exec_tb(tb, pc, cpu->cpu_index) to read my
> > trace, and now wondering should not it be there by default? Am I
> > missing something?
>
> Not necessarily but be aware trace_exec_tb won't catch every execution
> of a TB without -d nochain anyway. There are other trace points/logging
> methods you could use (-d cpu) which follow the executed PC more closely
> although without the TB associated with it, although again needing
> nochain for completeness.

Also odd is: why is the trace_exec_tb() tracepoint duplicated before
both calls to cpu_tb_exec() rather than just being once inside
the function itself, where the CPU_LOG_EXEC logging happens ?

(I suspect the answer partly here is "most people logging CPU
execution stuff use the -d logging, not the tracepoints", but
I could be wrong and maybe that's just the way I do it.
Certainly the -d logging gives more detail, including TB
flags and symbol information for the PC value.)

thanks
-- PMM