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From:   Jani Nikula <jani.nikula@linux.intel.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>,
        Dave Young <dyoung@redhat.com>
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        John Hubbard <jhubbard@nvidia.com>,
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        Prarit Bhargava <prarit@redhat.com>
Subject: Re: [PATCH RFC 1/2] coding-style.rst: document BUG() and WARN()
 rules ("do not crash the kernel")
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Date:   Mon, 29 Aug 2022 12:25:02 +0300
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On Sun, 28 Aug 2022, Linus Torvalds <torvalds@linux-foundation.org> wrote:
> So WARN_ON_ONCE() is the thing to aim for. BUG_ON() is the thing for
> "oops, I really don't know what to do, and I physically *cannot*
> continue" (and that is *not* "I'm too lazy to do error handling").

Any insight for the tradeoff between WARN_ON_ONCE() and WARN_ON(),
i.e. wasting the static once variable per use site vs. littering the
dmesg on every hit? I see there have been some improvements with the
__WARN_FLAGS() stuff, but is the data use really neglible?

BR,
Jani.


-- 
Jani Nikula, Intel Open Source Graphics Center