NIC interrupt assignments under UltraSPARC-T1

NIC interrupt assignments under UltraSPARC-T1

[Rick Jones]

 From time to time I "play" with netperf on different systems.  I happen 
to have occasion to play with a T2000.  Under Solaris 10 I am able to 
coerce the interrupts of the different core GbEs to be on different 
cores rather than strands of the same core.

Under a 2.6.15 kernel (Ubuntu Dapper) it would appear that the old 
standby of "echo affinity mask to the IRQ" doesn't "work" - no matter 
how I change the mask for a NIC, running a netperf TCP_RR test seems to 
show the interrupts happening on the same strand.

Is it indeed not possible to alter the interrupt assignments or have I 
(as I'm wont to do) missed something quasi-obvious?

thanks,

rick jones

Re: NIC interrupt assignments under UltraSPARC-T1

[David Miller]

From: Rick Jones <rick.jones2@hp.com>
Date: Wed, 13 Sep 2006 17:47:27 -0700

> Is it indeed not possible to alter the interrupt assignments or have I 
> (as I'm wont to do) missed something quasi-obvious?

It should work, perhaps there is a bug somewhere.

I think it's a bad idea, btw, to asking sparc port questions
on the netdev list :-)  sparclinux@vger would be a much
better place.

I'm travelling currently, and won't be back until next week,
so I have no way to plug in and power on my T1000 machine to
try and diagnose this.  Please try and debug this yourself by
poking around in arch/sparc64/kernel/irq.c where this is supposed
to be happening.

Thanks.