From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bruce Richardson <bruce.richardson@intel.com>
Subject: Re: [PATCH v4] eal: restrict cores auto detection
Date: Fri, 9 Dec 2016 15:14:52 +0000
Message-ID: <20161209151451.GB14536@bricha3-MOBL3.ger.corp.intel.com>
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Cc: Jianfeng Tan <jianfeng.tan@intel.com>, dev@dpdk.org,
 david.marchand@6wind.com, pmatilai@redhat.com
To: Thomas Monjalon <thomas.monjalon@6wind.com>
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On Thu, Dec 08, 2016 at 07:19:41PM +0100, Thomas Monjalon wrote:
> 2016-12-02 17:48, Jianfeng Tan:
> > This patch uses pthread_getaffinity_np() to narrow down used
> > cores when none of below options is specified:
> >   * coremask (-c)
> >   * corelist (-l)
> >   * and coremap (--lcores)
> > 
> > The purpose of this patch is to leave out these core related options
> > when DPDK applications are deployed under container env, so that
> > users do not need decide the core related parameters when developing
> > applications. Instead, when applications are deployed in containers,
> > use cpu-set to constrain which cores can be used inside this container
> > instance. And DPDK application inside containers just rely on this
> > auto detect mechanism to start polling threads.
> > 
> > Note: previously, some users are using isolated CPUs, which could
> > be excluded by default. Please add commands like taskset to use
> > those cores.
> > 
> > Test example:
> > $ taskset 0xc0000 ./examples/helloworld/build/helloworld -m 1024
> 
> Bruce, what do you think of this version?
> It requires taskset only if -c, -l and --lcores are not used.
> 
I'm fine with that since it maintains backward compatibilty for those
options.

Acked-by: Bruce Richardson <bruce.richardson@intel.com>