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Date: Wed, 19 Feb 2003 17:53:02 -0500 (EST)
From: Ion Badulescu <ionut@badula.org>
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To: "David S. Miller" <davem@redhat.com>
cc: torvalds@transmeta.com, <linux-kernel@vger.kernel.org>,
       <James.Bottomley@steeleye.com>
Subject: Re: [PATCH] add new DMA_ADDR_T_SIZE define
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On Wed, 19 Feb 2003, David S. Miller wrote:

> Yes true, storing the two consequetive 32-bit values is better
> for store buffer compression of the cpu.  Using memset is much
> more inefficient because you push the full set of data once
> then you push non-compressible stores to the same data through
> the cpu.
> 
> I'm not talking out of my ass, I've measured this.

So is the current wisdom something like "always treat dma_addr_t as a u64
and be happy"?

Ion

-- 
  It is better to keep your mouth shut and be thought a fool,
            than to open it and remove all doubt.

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