Return-path: Received: from ik-out-1112.google.com ([66.249.90.176]:10866 "EHLO ik-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750878AbYGYSfx (ORCPT ); Fri, 25 Jul 2008 14:35:53 -0400 Received: by ik-out-1112.google.com with SMTP id c28so2798930ika.5 for ; Fri, 25 Jul 2008 11:35:51 -0700 (PDT) Date: Fri, 25 Jul 2008 20:36:22 +0200 From: Jarek Poplawski To: Ingo Oeser Cc: David Miller , 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 Subject: Re: Kernel WARNING: at net/core/dev.c:1330 __netif_schedule+0x2c/0x98() Message-ID: <20080725183622.GA3107@ami.dom.local> (sfid-20080725_203602_626786_F66C7AF2) References: <1216806614.7257.152.camel@twins> <1216810696.7257.175.camel@twins> <20080723.131441.200166513.davem@davemloft.net> <200807251904.37302.netdev@axxeo.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <200807251904.37302.netdev@axxeo.de> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Fri, Jul 25, 2008 at 07:04:36PM +0200, Ingo Oeser wrote: ... > I'm sure as hell, I miss sth. but can't it be done by this pseudo-code: ...And I really doubt it can't be done like this. Jarek P. > > netif_tx_lock(device) > { > mutex_lock(device->queue_entry_mutex); > foreach_queue_entries(queue, device->queues) > { > spin_lock(queue->tx_lock); > set_noop_tx_handler(queue); > spin_unlock(queue->tx_lock); > } > mutex_unlock(device->queue_entry_mutex); > } > > netif_tx_unlock(device) > { > mutex_lock(device->queue_entry_mutex); > foreach_queue_entries(queue, device->queues) > { > spin_lock(queue->tx_lock); > set_useful_tx_handler(queue); > spin_unlock(queue->tx_lock); > } > mutex_unlock(device->queue_entry_mutex); > } > > Then protect use of the queues by queue->tx_lock in transmit path. > The first setup of the queue doesn't need to be protected, since no-one > knows the device. The final cleanup of the device doesn't need to be > protected either, because netif_tx_lock() and netif_tx_unlock() should > not be called after entering the final cleanup. > > Some VM locking works this way... > > > Best Regards > > Ingo Oeser