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Subject: Re: [PATCH] ext3_clear_inode(): avoid kfree(NULL)
From: Arjan van de Ven <arjan@infradead.org>
To: Andrew Morton <akpm@osdl.org>
Cc: Jeff Garzik <jeff@garzik.org>, linux-kernel@vger.kernel.org,
       torvalds@osdl.org
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Date: Sat, 24 Jun 2006 14:11:43 +0200
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> 
> Because at that callsite, NULL is the common case.  We avoid a do-nothing
> function call most of the time.  It's a nano-optimisation.

but a function call is basically free, while an if () is not... even
with unlikely()...

sounds like a misoptimization to me.