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Date: Mon, 30 Mar 2015 11:15:05 -0700
From: Stephen Hemminger <stephen@networkplumber.org>
To: Don Provan <dprovan@bivio.net>
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Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] [PATCH] mbuf: add comment explaining confusing code
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On Mon, 30 Mar 2015 17:39:06 +0000
Don Provan <dprovan@bivio.net> wrote:

> In all the debate about atomics, I don't think anyone got around to pointing out that in the unlikely case that the refcnt is not 1, then it's equally unlikely that decrementing it will result in 0 despite the code's claim to the contrary. That's the part that confused me. Would it make sense to fix this while adding the comment?

Really doubt the second likely() makes any difference in code speed.
Should probably just be removed.