[dpdk-dev] [PATCH 2/8] trace: simplify trace point registration

[David Marchand]

On Tue, May 5, 2020 at 5:25 PM Jerin Jacob <jerinjacobk at gmail.com> wrote:
>
> On Tue, May 5, 2020 at 5:56 PM Jerin Jacob <jerinjacobk at gmail.com> wrote:
> >
> > On Tue, May 5, 2020 at 5:06 PM David Marchand <david.marchand at redhat.com> wrote:
> > >
> > > On Tue, May 5, 2020 at 12:13 PM Jerin Jacob <jerinjacobk at gmail.com> wrote:
> > > > > > Please share the data.
> > > > >
> > > > > Measured time between first rte_trace_point_register and last one with
> > > > > a simple patch:
> > > >
> > > > I will try to reproduce this, once we finalize on the above synergy
> > > > with rte_log.
> > >
> > > I took the time to provide measure but you won't take the time to look at this.
> >
> > I will spend time on this. I would like to test with a shared library
> > also and more tracepoints.
> > I was looking for an agreement on using the constructor for rte_log as
> > well(Just make sure the direction is correct).
> >
> > Next steps:
> > - I will analyze the come back on this overhead on this thread.
>
> I have added 500 constructors for testing the overhead with the shared
> build and static build.
> My results inline with your results aka negligible overhead.
>
> David,
> Do you have plan for similar RTE_LOG_REGISTER as mentioned earlier?
> I would like to have rte_log and rte_trace semantics similar to registration.
> If you are not planning to submit the rte_log patch then I can send
> one for RC2 cleanup.

It won't be possible for me.

Relying on the current rte_log_register is buggy with shared builds,
as drivers are calling rte_log_register, then impose a default level
without caring about what the user passed.
So if we introduce a RTE_LOG_REGISTER macro now at least this must be fixed too.

What I wanted to do:
- merge rte_log_register_and_pick_level() (experimental) into
rte_log_register, doing this should be fine from my pov,
- reconsider the relevance of a fallback logtype when registration fails,
- shoot the default level per component thing: levels meaning is
fragmented across the drivers/libraries because of it, but this will
open a big box of stuff,



-- 
David Marchand