Re: [PATCH v12 3/3] tracing: Centralize preemptirq tracepoints and unify their usage

From: Steven Rostedt
Date: Tue Aug 07 2018 - 09:49:59 EST


On Tue, 7 Aug 2018 06:33:35 -0700
Joel Fernandes <joelaf@xxxxxxxxxx> wrote:

> Thanks, also one more thing I noticed in your patch,
> lockdep_hardirqs_off needs to be called before all other probes but
> you're calling it after. This is why I registered it with INT_MAX:
>
> register_trace_prio_irq_disable(lockdep_hardirqs_off, NULL, INT_MAX);
>
> Without it you may get annotation warnings. Thanks,

Interesting. I was following the old way where we called the tracing
code before calling the lockdep code (all hard coded and not from
trace events). Is this have something to do with calling the code from
a tracepoint?

Do you have an example that could trigger the warning?

-- Steve