From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarek Poplawski Subject: Re: Kernel WARNING: at net/core/dev.c:1330 __netif_schedule+0x2c/0x98() Date: Sat, 26 Jul 2008 12:53:08 +0200 Message-ID: <20080726105308.GA2524@ami.dom.local> References: <20080725193416.GB3107@ami.dom.local> <1217014575.4758.7.camel@johannes.berg> <20080725200137.GC3107@ami.dom.local> <20080726.021846.236624483.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: johannes@sipsolutions.net, netdev@axxeo.de, peterz@infradead.org, Larry.Finger@lwfinger.net, kaber@trash.net, torvalds@linux-foundation.org, akpm@linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-wireless@vger.kernel.org, mingo@redhat.com To: David Miller Return-path: Received: from ik-out-1112.google.com ([66.249.90.178]:57714 "EHLO ik-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750832AbYGZKxU (ORCPT ); Sat, 26 Jul 2008 06:53:20 -0400 Received: by ik-out-1112.google.com with SMTP id c28so3112758ika.5 for ; Sat, 26 Jul 2008 03:53:17 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20080726.021846.236624483.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-ID: On Sat, Jul 26, 2008 at 02:18:46AM -0700, David Miller wrote: > From: Jarek Poplawski > Date: Fri, 25 Jul 2008 22:01:37 +0200 > > > On Fri, Jul 25, 2008 at 09:36:15PM +0200, Johannes Berg wrote: > > > On Fri, 2008-07-25 at 21:34 +0200, Jarek Poplawski wrote: > > > > > > No, we need to be able to lock out multiple TX paths at once. > > > > IMHO, it can do the same. We could e.g. insert a locked spinlock into > > this noop_tx_handler(), to give everyone some waiting. > > I think there might be an easier way, but we may have > to modify the state bits a little. Yes, this looks definitely easier, but here is this one little bit more, plus additional code to handle this in various places. Ingo's proposal needs a (one?!) bit more thinking in one place, but it shouldn't add even a bit to tx path (and it looks really cool!). Of course, it could be re-considered in some other time too. BTW, it seems with "Ingo's method" this netif_queue_stopped() check could be removed too - the change of handlers could be done with single qdiscs as well. Jarek P.