From mboxrd@z Thu Jan  1 00:00:00 1970
From: Olivier MATZ <olivier.matz@6wind.com>
Subject: Re: [PATCH v4] mbuf: fix mbuf free performance with non
 atomic refcnt
Date: Mon, 11 Dec 2017 11:28:25 +0100
Message-ID: <20171211102824.fshpnmxuxun5pp54@platinum>
References: <20171115091413.27119-1-hhaim@cisco.com>
 <20171208154651.16546-1-olivier.matz@6wind.com>
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On Fri, Dec 08, 2017 at 04:46:51PM +0100, Olivier Matz wrote:
> When RTE_MBUF_REFCNT_ATOMIC=n, the decrement of the mbuf reference
> counter uses an atomic operation. This is not necessary and impacts
> the performance (seen with TRex traffic generator).
> 
> We cannot replace rte_atomic16_add_return() by rte_mbuf_refcnt_update()
> because it would add an additional check.
> 
> Solves this by introducing __rte_mbuf_refcnt_update(), which
> updates the reference counter without doing anything else.
> 
> Fixes: 8f094a9ac5d7 ("mbuf: set mbuf fields while in pool")
> Suggested-by: Hanoch Haim <hhaim@cisco.com>
> Signed-off-by: Olivier Matz <olivier.matz@6wind.com>

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