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Date: Wed, 17 Aug 2005 10:47:12 +0300
From: Avi Kivity <avi@argo.co.il>
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To: Jens Axboe <axboe@suse.de>
CC: Alejandro Bonilla Beeche <abonilla@linuxwireless.org>,
       linux-kernel <linux-kernel@vger.kernel.org>,
       hdaps devel <hdaps-devel@lists.sourceforge.net>
Subject: Re: HDAPS, Need to park the head for real
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Jens Axboe wrote:

>Ok, I'll give you some hints to get you started... What you really want
>to do, is:
>
>- Insert a park request at the front of the queue
>- On completion callback on that request, freeze the block queue and
>  schedule it for unfreeze after a given time
>
>  
>
how will this interact with command queuing? there is a danger from both 
commands previously queued but not yet completed, and commands that are 
queued after the park request. or is the park request a barrier?