Re: [RFC PATCH 3/7] core/metricfs: metric for kernel warnings

Greg KH
2020-08-08T05:45:09Z

On Fri, Aug 07, 2020 at 02:29:12PM -0700, Jonathan Adams wrote:
> Count kernel warnings by function name of the caller.
>
> Each time WARN() is called, which includes WARN_ON(), increment a counter
> in a 256-entry hash table. The table key is the entry point of the calling
> function, which is found using kallsyms.

Why is this needed?

As systems seem to like to reboot when WARN() is called, will this only
ever show 1? :)

>
> We store the name of the function in the table (because it may be a
> module address); reporting the metric just walks the table and prints
> the values.
>
> The "warnings" metric is cumulative.

If you are creating specific files in a specific location that people
can rely on, shouldn't they show up in Documentation/ABI/ as well?

But again, is this feature something that anyone really needs/wants?
What can the number of warnings show you?

thanks,

greg k-h