[dpdk-dev] [PATCH] ring: guarantee ordering of cons/prod loading when doing enqueue/dequeue

[Jerin Jacob]

-----Original Message-----
> Date: Wed, 1 Nov 2017 12:48:31 +0800
> From: Jia He <hejianet at gmail.com>
> To: Jerin Jacob <jerin.jacob at caviumnetworks.com>
> Cc: "Ananyev, Konstantin" <konstantin.ananyev at intel.com>, "Zhao, Bing"
>  <ilovethull at 163.com>, Olivier MATZ <olivier.matz at 6wind.com>,
>  "dev at dpdk.org" <dev at dpdk.org>, "jia.he at hxt-semitech.com"
>  <jia.he at hxt-semitech.com>, "jie2.liu at hxt-semitech.com"
>  <jie2.liu at hxt-semitech.com>, "bing.zhao at hxt-semitech.com"
>  <bing.zhao at hxt-semitech.com>, "Richardson, Bruce"
>  <bruce.richardson at intel.com>, jianbo.liu at arm.com, hemant.agrawal at nxp.com
> Subject: Re: [dpdk-dev] [PATCH] ring: guarantee ordering of cons/prod
>  loading when doing enqueue/dequeue
> User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101
>  Thunderbird/52.4.0
> 
> Hi Jerin
> 
> 
> On 10/31/2017 7:14 PM, Jerin Jacob Wrote:
> > -----Original Message-----
> > > Date: Tue, 31 Oct 2017 10:55:15 +0800
> > > From: Jia He <hejianet at gmail.com>
> > > To: Jerin Jacob <jerin.jacob at caviumnetworks.com>
> > > Cc: "Ananyev, Konstantin" <konstantin.ananyev at intel.com>, "Zhao, Bing"
> > >   <ilovethull at 163.com>, Olivier MATZ <olivier.matz at 6wind.com>,
> > >   "dev at dpdk.org" <dev at dpdk.org>, "jia.he at hxt-semitech.com"
> > >   <jia.he at hxt-semitech.com>, "jie2.liu at hxt-semitech.com"
> > >   <jie2.liu at hxt-semitech.com>, "bing.zhao at hxt-semitech.com"
> > >   <bing.zhao at hxt-semitech.com>, "Richardson, Bruce"
> > >   <bruce.richardson at intel.com>
> > > Subject: Re: [dpdk-dev] [PATCH] ring: guarantee ordering of cons/prod
> > >   loading when doing enqueue/dequeue
> > > User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101
> > >   Thunderbird/52.4.0
> > > 
> > > Hi Jerin
> > Hi Jia,
> > 
> > > Do you think  next step whether I need to implement the load_acquire half
> > > barrier as per freebsd
> > I did a quick prototype using C11 memory model(ACQUIRE/RELEASE) schematics
> > and tested on two arm64 platform in Cavium(Platform A: Non arm64 OOO machine)
> > and Platform B: arm64 OOO machine)
> Can you elaborate anything about your Non arm64 OOO machine? As I know, all
> arm64 server is strong
> memory order. Am I missed anything?

It is implementation defined. The low end arm64 boxes(non server) may not have the
complete OOO support.