Re: [patch 4/8] x86/entry: Move irq tracing on syscall entry to C-code

Steven Rostedt
2020-03-01T18:23:10Z

On Sun, 1 Mar 2020 08:00:01 -0800
Andy Lutomirski <luto@kernel.org> wrote:

> But the DEFINE_EVENT doesn't have the "_rcuidle" part. And that's
> where I got lost in the macro maze. I looked at the gcc asm output,
> and there is, indeed:
>
> # ./include/trace/events/preemptirq.h:40:
> DEFINE_EVENT(preemptirq_template, irq_enable,
>
> with a bunch of asm magic that looks like it's probably a tracepoint.
> I still don't quite see where the "_rcuidle" went.

See the code in include/linux/tracepoint.h and search for "rcuidle"
there. All defined trace events get a "_rcuidle" version, but as it is
declared a static inline, then they only show up if they are used.

-- Steve