Date: Thu, 22 Jun 2017 10:04:56 +0200
From: Michal Kubecek <mkubecek@suse.cz>
To: Michael J Dilmore <michael.j.dilmore@gmail.com>
Cc: Jay Vosburgh <jay.vosburgh@canonical.com>,
        David Miller <davem@davemloft.net>, vfalico@gmail.com,
        andy@greyhouse.net, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, joe@perches.com
Subject: Re: [PATCH] Convert BUG_ON to WARN_ON in bond_options.c
Message-ID: <20170622080456.GC6104@unicorn.suse.cz>
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On Thu, Jun 22, 2017 at 12:04:54AM +0100, Michael J Dilmore wrote:
> 
> Is it worth at least wrapping BUG_ON in an unlikely macro then?

See BUG_ON() definition:

#ifndef HAVE_ARCH_BUG_ON
#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
#endif

where HAVE_ARCH_BUG_ON is defined only on powerpc and mips. It makes
good sense, you don't want to BUG_ON() on a condition unless it's
extremely unlikely. (Except for debugging purpose but even then you
don't really care about fine optimization when you are going to oops.)

Michal Kubecek