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Subject: Re: [PATCH] UBI: new module ubiblk: block layer on top of UBI
From: Artem Bityutskiy <dedekind1@gmail.com>
To: David Wagner <david.wagner@free-electrons.com>
Date: Wed, 29 Jun 2011 09:52:01 +0300
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On Tue, 2011-06-28 at 13:35 +0200, David Wagner wrote:
> Hi,
> 
> On 06/27/2011 09:26 PM, Artem Bityutskiy wrote:
> > On Fri, 2011-06-24 at 15:34 +0200, david.wagner@free-electrons.com
> > wrote:
> >> +	/* Stolen from mtd_blkdevs.c */
> >> +	/* Create processing thread */
> >> +	dev->thread = kthread_run(ubi_ubiblk_thread, dev, "%s%d_%d",
> >> +				  "kubiblkd", dev->ubi_num, dev->vol_id);
> >> +	if (IS_ERR(dev->thread)) {
> >> +		ret = PTR_ERR(dev->thread);
> >> +		goto out_thread;
> >> +	}
> > 
> > Why we need a kernel thread? Could you please describe when exactly it
> > is needed and why we cannot avoid having it?
> 
> Do you mean that there could be another/better way ?

No, I just do not understand why it is there. I think this is juts block
layer's design, but I wanted you to explain this - the design, how block
requests are handled, and where exactly the thread is needed. I expected
you just have the explanation.

-- 
Best Regards,
Artem Bityutskiy