Re: [POC][RFC][PATCH 1/3] tracing: Add perf events

[Steven Rostedt]

On Tue, 18 Nov 2025 09:35:10 +0100
Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:

> > +	cpu = smp_processor_id();
> > +
> > +	e = per_cpu_ptr(events, cpu)->event;
> > +	if (!e)
> > +		return 0;
> > +
> > +	e->pmu->read(e);
> > +	return local64_read(&e->count);
> > +}  
> 
> NAK, wtf do you think its okay to use internal stuff like that? And
> wrongly while at it.

Peter, this is a PROOF-OF-CONCEPT. It means I'm showing the concept and not
the implementation. I'm hoping the NAK is on the implementation and not the
concept.

> 
> What you wanted to use was perf_event_read_local().

Great! I didn't know about that. Which is why I posted this as a
PROOF-OF-CONCEPT and not even a normal RFC, so that I could learn about the
proper way of doing this.

-- Steve