From mboxrd@z Thu Jan  1 00:00:00 1970
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: [Xen-devel] [PATCH 1/8] netback: don't bind kthread to cpu
Date: Tue, 5 Mar 2013 08:56:49 -0500
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To: Wei Liu <wei.liu2@citrix.com>
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On Tue, Mar 05, 2013 at 01:30:10PM +0000, Wei Liu wrote:
> On Mon, 2013-03-04 at 20:51 +0000, Konrad Rzeszutek Wilk wrote:
> > On Fri, Feb 15, 2013 at 04:00:02PM +0000, Wei Liu wrote:
> > > The initialization process makes an assumption that the online cpus are
> > > numbered from 0 to xen_netbk_group_nr-1,  which is not always true.
> > 
> > And xen_netbk_group_nr is num_online_cpus()?
> > 
> 
> Yes.
> 
> > So under what conditions does this change? Is this when the CPU hotplug
> > is involved and the CPUs go offline? In which case should there be a
> 
> Yes, the hotplug path.
> 
> > CPU hotplug notifier to re-bind the workers are appropiate?

?
Can't that option be explored?
> > 
> > > 
> > > As we only need a pool of worker threads, simply don't bind them to specific
> > > cpus.
> > 
> > OK. Is there another method of doing this? Are there patches to make the thread
> > try to be vCPU->guest affinite?
> > 
> 
> No, not at the moment.
> 
> 
> Wei.
> 
> 
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