From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH] NETIF_F_LLTX for devices 2 Date: Mon, 13 Sep 2004 12:10:03 -0400 Sender: netdev-bounce@oss.sgi.com Message-ID: <4145C65B.4050703@pobox.com> References: <20040908072408.GI27886@wotan.suse.de> <1094629677.1089.155.camel@jzny.localdomain> <20040908134713.1bcd46d3.davem@davemloft.net> <1094823215.1121.129.camel@jzny.localdomain> <20040911142116.GL4431@wotan.suse.de> <1094933731.2343.109.camel@jzny.localdomain> <20040911174535.2acbb957.davem@davemloft.net> <20040912100114.GB11484@havoc.gtf.org> <20040912102529.GA27096@wotan.suse.de> <20040912161604.GA23366@havoc.gtf.org> <20040913065958.GC12185@wotan.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: "David S. Miller" , hadi@cyberus.ca, herbert@gondor.apana.org.au, netdev@oss.sgi.com Return-path: To: Andi Kleen In-Reply-To: <20040913065958.GC12185@wotan.suse.de> Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org Andi Kleen wrote: > On Sun, Sep 12, 2004 at 12:16:05PM -0400, Jeff Garzik wrote: > >>Incorrect, you are changing the callsites, which -does- affect every >>driver. > > > Please read the code before making such claims. > > The new return code is _only_ checked when NETIF_F_LLTX is set. > A driver that doesn't set this new flag won't ever recognize > any difference. I read the code :) The basic premise is that one should be _really_ conservative when touching the core RX and TX paths. Regardless of how safe _you_ feel the code is, it is very new, under-analyzed, and untried. The NAPI-related bug recently fixed in tg3 is an example of the unintended consequences of using this new feature. Jeff