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Date: Mon, 26 Jul 2010 18:51:22 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Tejun Heo <tj@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>, Sridhar Samudrala <sri@us.ibm.com>,
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Subject: Re: [PATCH UPDATED 1/3] vhost: replace vhost_workqueue with
 per-vhost kthread
Message-ID: <20100726155122.GB26412@redhat.com>
References: <20100531160020.GC3067@redhat.com>
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On Mon, Jul 26, 2010 at 05:46:30PM +0200, Tejun Heo wrote:
> On 07/26/2010 05:34 PM, Tejun Heo wrote:
> > Hello,
> > 
> > On 07/26/2010 05:25 PM, Michael S. Tsirkin wrote:
> >> BTW, kthread_worker would benefit from the optimization I implemented
> >> here as well.
> > 
> > Hmmm... I'm not quite sure whether it's an optimization.  I thought
> > the patch was due to feeling uncomfortable about using barriers?  Is
> > it an optimization?
> 
> Yeah, one less smp_mb() in execution path.  The lock dancing in
> flush() is ugly but then again mucking with barriers could be harder
> to understand.  Care to send a patch against wq#for-next tree?
> 
> Thanks.

Sure. Where's that, exactly?

> -- 
> tejun