Subject: Re: Ethernet Device Driver
To: matthew green <mrg@eterna.com.au>
From: Manuel Bouyer <bouyer@antioche.lip6.fr>
List: tech-ports
Date: 01/04/2001 14:05:11
On Thu, Jan 04, 2001 at 11:58:39PM +1100, matthew green wrote:
> 
>    On Thu, Jan 04, 2001 at 02:17:12AM -0800, Tarachand Verma wrote:
>    > Hello:
>    > 
>    > We are looking for an enthernet device driver (fast or
>    > giga ethernet on
>    > PCI bus) which can run on the NetBSD/Intel-PC almost
>    > independent of the
>    > kernel and the OS in general.  The reason for that is
>    > to try achieve
>    > maximum performance for data communications and
>    > latency. 
>    
>    Such a driver can't be indepedant from the kernel, because only the
>    kernel has access to I/O port and buffers.
>    Now it's possible to write a simple kernel drivers wich just allows a
>    user process to mmap the buffers, and gives the I/O ports.
>    Then the user process could drive the device by itself.
> 
> 
> you are of course correct, manuel...  but this really won't give
> someone "maximum performance for data communications and latency."

It would avoid a context switch, isn't it ?
Hum, there's issues with interrupts I didn't think about.

--
Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
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