From mboxrd@z Thu Jan 1 00:00:00 1970 From: jamal Subject: Re: [NET]: Prevent multiple qdisc runs Date: Thu, 22 Jun 2006 20:52:17 -0400 Message-ID: <1151023937.5099.40.camel@jzny2> References: <20060619121519.GA16031@gondor.apana.org.au> <1150724031.5815.39.camel@jzny2> <20060619134227.GA16662@gondor.apana.org.au> <1150727009.5815.72.camel@jzny2> <20060619142928.GA17191@gondor.apana.org.au> <1150727810.5815.78.camel@jzny2> <20060619223326.GA20354@gondor.apana.org.au> <1150814526.5270.64.camel@jzny2> <20060620235207.GA31493@gondor.apana.org.au> <1151004682.5392.97.camel@jzny2> <20060622224302.GA10136@gondor.apana.org.au> Reply-To: hadi@cyberus.ca Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: Robert Olsson , "David S. Miller" , netdev@vger.kernel.org Return-path: Received: from mx03.cybersurf.com ([209.197.145.106]:49073 "EHLO mx03.cybersurf.com") by vger.kernel.org with ESMTP id S1751090AbWFWAwU (ORCPT ); Thu, 22 Jun 2006 20:52:20 -0400 Received: from mail.cyberus.ca ([209.197.145.21]) by mx03.cybersurf.com with esmtp (Exim 4.30) id 1FtZuN-0000uO-0F for netdev@vger.kernel.org; Thu, 22 Jun 2006 20:52:27 -0400 To: Herbert Xu In-Reply-To: <20060622224302.GA10136@gondor.apana.org.au> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, 2006-23-06 at 08:43 +1000, Herbert Xu wrote: > Sure. However, I still don't see the point of transmitting in parallel > even there. The reason is that there is no work being done here by the > CPU between dequeueing the packet and obtaining the TX lock. You make a reasonable argument. I think I will need to run the experiment to gather facts. I will defer this discussion until i run some tests or Robert beats me to it. It does feel like the qdisc_is_running though is now a replacement for the need for dev->txlock which existed to protect multi-cpus from entering the device transmit path. Is that unintended side effect? i.e why would dev->txlock be needed anymore in that path? cheers, jamal