From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH 1/2] pkt_sched: Fix gen_estimator locks Date: Wed, 27 Aug 2008 04:15:11 -0700 (PDT) Message-ID: <20080827.041511.189138671.davem@davemloft.net> References: <20080827104457.GA7258@ff.dom.local> <20080827.034723.73512507.davem@davemloft.net> <20080827110938.GB7258@ff.dom.local> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: herbert@gondor.apana.org.au, netdev@vger.kernel.org To: jarkao2@gmail.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:39801 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753690AbYH0LPQ (ORCPT ); Wed, 27 Aug 2008 07:15:16 -0400 In-Reply-To: <20080827110938.GB7258@ff.dom.local> Sender: netdev-owner@vger.kernel.org List-ID: From: Jarek Poplawski Date: Wed, 27 Aug 2008 11:09:39 +0000 > On Wed, Aug 27, 2008 at 03:47:23AM -0700, David Miller wrote: > > From: Jarek Poplawski > > Date: Wed, 27 Aug 2008 10:44:58 +0000 > > > > > Yes, it should be simpler. (We can probably consider a pointer to > > > itself instead of NULL for root qdiscs, to skip testing for NULL e.g. > > > while getting a lock.) On the other hand, we lose with this the > > > possibility to easily determine which dev_queue is "the owner" of the > > > qdisc, or if some dev_queue contains a clone only. > > > > For root qdiscs we can add a TCQ_F_SHARED flag for this purpose. > > Yes, but we can't do something like this: Good point. We could go back to using a device scope list. The only piece to solve at that point is how to differentiate the different entries in the non-shared multiq case. What it comes down to is semantics, and how we might want to handle multiq non-shared cases in future uses. Maybe some day we'll allow real complicated configurations, such as mixes of shared and non-shared qdiscs on the TX queues. So we'd need to think about how that would look, implementation wise.