From: Stephen Hemminger <stephen@networkplumber.org>
To: lilinzhe <slayercat.subscription@gmail.com>
Cc: dev@dpdk.org, 李林哲 <lilinzhe@ijinshan.com>
Subject: Re: [dpdk-dev] [PATCH] mbuf: fix atomic refcnt update synchronization
Date: Fri, 2 Sep 2016 09:12:36 -0700 [thread overview]
Message-ID: <20160902091236.57250d1a@xeon-e3> (raw)
In-Reply-To: <1472793906-5699-1-git-send-email-slayercat.subscription@gmail.com>
On Fri, 2 Sep 2016 13:25:06 +0800
lilinzhe <slayercat.subscription@gmail.com> wrote:
> From: 李林哲 <lilinzhe@ijinshan.com>
>
> chagne atomic ref update to always call atomic_add
>
> when mbuf is allocated by cpu1 and freed by cpu2. cpu1 cache may not be updated by such a set operation.
> causes refcnt reads incorrect values.
What architecture are you dealing with? On X86 memory is cache coherent.
Doing atomic operation all the time on each mbuf free would significantly
slow down performance.
next prev parent reply other threads:[~2016-09-02 16:12 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-02 5:25 lilinzhe
2016-09-02 16:12 ` Stephen Hemminger [this message]
2016-09-02 16:31 ` Linzhe Lee
2016-09-02 16:51 ` Stephen Hemminger
2016-09-03 2:05 ` Linzhe Lee
2016-09-03 22:52 ` Ananyev, Konstantin
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