Re: [PATCH v2 3/5] docs: ABI: add /sys/kernel/error_report/ documentation

From: Steven Rostedt
Date: Mon Jan 18 2021 - 09:54:16 EST


On Mon, 18 Jan 2021 11:22:27 +0100
Alexander Potapenko <glider@xxxxxxxxxx> wrote:

> > If you do use tracefs, add it to the top level tracing directory (no need
> > to have instances of it), and rename it to "kernel_warnings", as
> > "error_report" is too close to the existing "error_log" which holds error
> > messages of syntactic errors done by users entering in commands to some of
> > the special files.
>
> Will do. Is it conventional to add a new dentry* to struct trace_array for that?
> If not, maybe it's better to create this dir in
> error_report_notify_setup(), like this is done e.g. for
> /sys/kernel/tracing/trace_stat - just to loosen the coupling?

Yeah, keep the dentry static in your own code. No need to add it to the
trace_array. The dentry's in the trace array are for instances (as there
are more than one of instance of them).

>
> > That is, /sys/kernel/tracing/kernel_warnings/ would be your error_report/
> > directory you have now.
>
> WDYT about "kernel_errors" or "kernel_error_reports"?
> "warnings" suggest we'll be notifying about any occurrence of WARN(),
> which is not what we are planning to do.
> Also, shall I rename the library/config/etc. accordingly (to e.g.
> CONFIG_KERNEL_WARN_NOTIFY)?

I'm fine with "kernel_errors" as that helps to differentiate what they are.
Also, you may want to add a field about this in the documentation under
Documentation/trace/ftrace.rst (just a reference) and add a separate file
called, kernel_errors.rst.

-- Steve