Re: [PATCH 00/15] tracepoint: Avoid double static_branch evaluation at guarded call sites

Vineeth Remanan Pillai
2026-03-13T14:02:46Z

On Thu, Mar 12, 2026 at 1:03 PM Steven Rostedt <rostedt@goodmis.org> wrote:
>
> On Thu, 12 Mar 2026 09:54:29 -0700
> Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote:
>
> > > > emit_trace_foo()
> > > > __trace_foo()
> >
> > this seems like the best approach, IMO. double-underscored variants
> > are usually used for some specialized/internal version of a function
> > when we know that some conditions are correct (e.g., lock is already
> > taken, or something like that). Which fits here: trace_xxx() will
> > check if tracepoint is enabled, while __trace_xxx() will not check and
> > just invoke the tracepoint? It's short, it's distinct, and it says "I
> > know what I am doing".
>
> Honestly, I consider double underscore as internal only and not something
> anyone but the subsystem maintainers use.
>
> This, is a normal function where it's just saying: If you have it already
> enabled, then you can use this. Thus, I don't think it qualifies as a "you
> know what you are doing".
>
> Perhaps: call_trace_foo() ?
>
call_trace_foo has one collision with the tracepoint
sched_update_nr_running and a function
call_trace_sched_update_nr_running. I had considered this and later
moved to trace_invoke_foo() because of the collision. But I can rename
call_trace_sched_update_nr_running to something else if call_trace_foo
is the general consensus.

Thanks,
Vineeth