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From: Don Provan <dprovan@bivio.net>
To: "Richardson, Bruce" <bruce.richardson@intel.com>,
	Neil Horman <nhorman@tuxdriver.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] [PATCH] mbuf: add comment explaining confusing code
Date: Mon, 30 Mar 2015 17:39:06 +0000	[thread overview]
Message-ID: <CY1PR0101MB098798EEE9925C308B388CCDA0F50@CY1PR0101MB0987.prod.exchangelabs.com> (raw)
In-Reply-To: <59AF69C657FD0841A61C55336867B5B0344F112F@IRSMSX103.ger.corp.intel.com>

> > > > > > > >  	if (likely (rte_mbuf_refcnt_read(m) == 1) ||
> > > > > > > >  			likely (rte_mbuf_refcnt_update(m, -1) == 0))

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?
-don
dprovan@bivio.net

  parent reply	other threads:[~2015-03-30 17:39 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-26 21:14 Bruce Richardson
2015-03-26 21:31 ` Olivier MATZ
2015-03-27 10:29 ` Neil Horman
2015-03-27 10:49   ` Ananyev, Konstantin
2015-03-27 11:32   ` Bruce Richardson
2015-03-27 12:42     ` Neil Horman
2015-03-27 14:07     ` Neil Horman
2015-03-27 14:30       ` Bruce Richardson
2015-03-27 14:38         ` Neil Horman
2015-03-27 14:55           ` Bruce Richardson
2015-03-27 16:43             ` Neil Horman
2015-03-27 16:56               ` Richardson, Bruce
2015-03-30 17:11                 ` Thomas Monjalon
2015-03-30 17:39                 ` Don Provan [this message]
2015-03-30 18:15                   ` Stephen Hemminger
2015-03-31 12:33                   ` Zoltan Kiss
2015-03-30 19:39         ` Marc Sune
2015-03-30 20:26           ` Neil Horman

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