From owner-freebsd-hackers  Sat Aug 16 18:31:50 1997
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To: Vinay Bannai <vinay@agni.nuko.com>
cc: freebsd-hackers@FreeBSD.ORG
Subject: Re: Device drivers and DMA details?? 
In-reply-to: Your message of "Sat, 16 Aug 1997 17:52:23 PDT."
             <199708170052.RAA25354@agni.nuko.com> 
From: David Greenman <dg@root.com>
Reply-To: dg@root.com
Date: Sat, 16 Aug 1997 18:33:20 -0700
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>Also, while examining the fxp driver, the fxp_start() seems to be
>invoked at the time of each incoming packet (or interrupt from the
>device). Wouldn't this not create a delay in sending packets? Or is it
>that the fxp_start() also gets invoked whenever a packet is shoved on
>the network IF queues? 

   The driver start routine is also called when a packet is sent. See the
end of the ether_output() function in /sys/net/if_ethersubr.c.

-DG

David Greenman
Core-team/Principal Architect, The FreeBSD Project