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From: 金健 <jin_j@neusoft.com>
To: Stephen Hemminger <stephen@networkplumber.org>,
	chen_lp <chen_lp@neusoft.com>
Cc: dev@dpdk.org
Subject: Re: [dpdk-dev] Does the rte_eth_tx_burst() function is multi-threaded safe when sending pkt in same port and same queue ?
Date: Thu, 9 Jan 2014 14:50:53 +0800	[thread overview]
Message-ID: <79761A4660DC4442BC906E23CF5FF574@jinjian> (raw)
In-Reply-To: <CAOaVG17y3NUDzFnVAvxz=oaqFojnyX=vC2wrmxkYTVTRjV=NoA@mail.gmail.com>

But when I read the code of  l2fwd (v1.5.1 examples), I found that two cores share only one queue of a port.

And it doesn't use any lock or other mechanism to ensure the safety.

How is it OK?

----- Original Message ----- 
From: "Stephen Hemminger" <stephen@networkplumber.org>
To: "chen_lp" <chen_lp@neusoft.com>
Cc: <dev@dpdk.org>
Sent: Thursday, January 09, 2014 2:28 PM
Subject: Re: [dpdk-dev] Does the rte_eth_tx_burst() function is multi-threaded safe when sending pkt in same port and same queue ?


> The rx and tx functions are safe only if a queue is not shared by
> multiple threads (or the threads synchronize through some other
> mechanism). The safest design is to only use a queue on a single core.
> You will see different architectures in the examples. Some use one
> queue per core, and others use separate receive and transmit cores.
> 
> On Wed, Jan 8, 2014 at 8:16 PM, chen_lp <chen_lp@neusoft.com> wrote:
>>
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      reply	other threads:[~2014-01-09  6:49 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-01-09  4:16 chen_lp
2014-01-09  6:28 ` Stephen Hemminger
2014-01-09  6:50   ` 金健 [this message]

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