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Date:   Sat, 8 Aug 2020 07:45:04 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Jonathan Adams <jwadams@google.com>
Cc:     linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        netdev@vger.kernel.org, kvm@vger.kernel.org,
        Paolo Bonzini <pbonzini@redhat.com>,
        Jim Mattson <jmattson@google.com>,
        David Rientjes <rientjes@google.com>
Subject: Re: [RFC PATCH 3/7] core/metricfs: metric for kernel warnings
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 <20200807212916.2883031-4-jwadams@google.com>
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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