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From: Daniel Phillips <phillips@arcor.de>
To: root@chaos.analogic.com, Imran Badr <imran.badr@cavium.com>
Subject: Re: Calculating kernel logical address ..
Date: Mon, 9 Sep 2002 20:17:32 +0200
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On Monday 09 September 2002 20:00, Richard B. Johnson wrote:
> For some reason, (claimed performance reasons) user-mode code
> has to be able to get data directly from hardware with no
> intervening copy operation. I think any claimed advantage goes
> away when you look at the overhead necessary for user-mode
> code to sleep before, and awaken after, the DMA operation but
> often marketing departments make those decisions.

Pfft.  Try turning off ide dma and see what happens.

-- 
Daniel
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