Broadcom (bce) support and POLLING

[Kirk Davis]

Hi,
	We have just upgraded to a Dell 2950 for our main BGP router.
With the constant rise in traffic through the box, I have started to
notice some dropped packets so I figured I would take a look at putting
the interfaces into polling more to squeeze a little more packets
through them.

	I have added the DEVICE_POLLING and HZ=1000 to the kernel.  I
turned on polling for the bce interfaces and they pass traffic at low
volumes (like ping tests).  If I put my fluke traffic generators on
either side of the box and try to ramp it up to even 100Mb (they are Gig
links) then the interfaces will stop responding.  Turning off polling
will get them to respond again.

	I know that the bce support in still quite new.  Has anyone else
testing with polling and the bce interfaces?  Is there any more
information that I can get for the developers to help track this down.
The system is not in production right now so I can use it for testing.

	As another note... I added some Intel (em) cards into the box
and tested with them.  Polling worked great on them but I was only able
to get about 200k packets per second before it starts dropping packets.
Is this about what I should expect?

[root@ ~]# uname -a
FreeBSD  6.2-RC1 FreeBSD 6.2-RC1 #2: Tue Nov 28 18:10:56 MST 2006
root@:/usr/obj/usr/src/sys/INET-GW  i386

---- Kirk