Re: netpoll question

[Steve Wise <swise@opengridcomputing.com>]

On Wed, 2007-03-28 at 16:28 -0700, Mark Huth wrote:
> Steve Wise wrote:
> > Hey all,
> >
> > I have netpoll question.  How does netpoll work with MSI/X, NAPI, and
> > nics that setup multiple RSS style receive queues for a single port?
> > >From what I can tell, if you're doing something like netdump using
> > netpoll for IO, then you might never process incoming packets that get
> > posted to the rx queues not associated with the main netdevice structure
> > because netpoll only calls the poll() function for the main netdev
> > struct.  Not the dummy netdevs setup for multiple rx queues.  
> >
> > Is this the case or am I confused?
> >
> > Thanks,
> >
> >
> > Steve
> You are correct.  Netpoll needs a bit of work, especially on the receive 
> side, for multi-queue and some other possible problems related to taking 
> locks when the system is frozen.  If I get some time soon, I'm going to 
> propose an overhaul to address some of these issues that show up in the 
> kgdboe and netdump cases.
> 
> Mark Huth

Hey Mark,

What are your thoughts on how to implement this?  

Scrub every softnet_data queue->poll_list for every cpu?  Or perhaps its
better to have a new function ptr off the netdev that sez "poll all rx
queues"?


Steve.