From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steve Wise Subject: Re: netpoll question Date: Wed, 28 Mar 2007 20:00:33 -0500 Message-ID: <1175130033.28767.19.camel@stevo-laptop> References: <1175119380.28767.4.camel@stevo-laptop> <460AFA3B.6090009@mvista.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Mark Huth Return-path: Received: from rrcs-24-153-217-226.sw.biz.rr.com ([24.153.217.226]:49941 "EHLO smtp.opengridcomputing.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934287AbXC2BAf (ORCPT ); Wed, 28 Mar 2007 21:00:35 -0400 In-Reply-To: <460AFA3B.6090009@mvista.com> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org 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.