Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261428AbVBWEWv (ORCPT ); Tue, 22 Feb 2005 23:22:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261422AbVBWEWv (ORCPT ); Tue, 22 Feb 2005 23:22:51 -0500 Received: from fire.osdl.org ([65.172.181.4]:46006 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S261412AbVBWEWp (ORCPT ); Tue, 22 Feb 2005 23:22:45 -0500 Message-ID: <421C04FA.8090706@osdl.org> Date: Tue, 22 Feb 2005 20:22:18 -0800 From: Stephen Hemminger User-Agent: Mozilla Thunderbird 1.0 (Windows/20041206) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Tobias DiPasquale CC: "David S. Miller" , John Heffner , mlists@danielinux.net, linux-net@vger.kernel.org, linux-kernel@vger.kernel.org, ccaini@deis.unibo.it, rfirrincieli@arces.unibo.it Subject: Re: [PATCH] TCP-Hybla proposal References: <200502221534.42948.mlists@danielinux.net> <20050222094219.0a8efbe1@dxpl.pdx.osdl.net> <20050222101447.68a02c12.davem@davemloft.net> <876ef97a050222164140968e15@mail.gmail.com> In-Reply-To: <876ef97a050222164140968e15@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1422 Lines: 34 > On Tue, 22 Feb 2005 10:14:47 -0800, David S. Miller wrote: > >>> On Tue, 22 Feb 2005 13:03:11 -0500 (EST) >>> John Heffner wrote: >>> >> >>>> > An idea I've been toying with for a while now is completely abstracting >>>> > congestion control. Then you could have congestion control loadable >>>> > modules, which would avoid this mess of experimental algorithms inside the >>>> > main-line kernel. If done right, they might be able to work seamlessly >>>> > with SCTP, too. The tricky part is making sure the interface is complete >>>> > enough. There might be a noticeable performance impact to making it truly modular. Calling a function in a module is slower. In some tests, I see a 5 to 10% drop in performance when Ethernet driver is a module versus builtin. You might want to look at how the I/O schedulers are configured as an example. >>> >>> The symbols exported to allow this would need to be EXPORT_SYMBOL_GPL(). > > > Why's that? Because the kernel developers who hold the collective copyright on the existing GPL TCP code do not want some vendor producing a closed source binary module of "enhanced TCP". - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/