Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 10 Oct 2001 11:28:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 10 Oct 2001 11:27:59 -0400 Received: from hq2.fsmlabs.com ([209.155.42.199]:28935 "HELO hq2.fsmlabs.com") by vger.kernel.org with SMTP id ; Wed, 10 Oct 2001 11:27:48 -0400 Date: Wed, 10 Oct 2001 09:23:00 -0600 From: Victor Yodaiken To: BALBIR SINGH Cc: Linus Torvalds , linux-kernel@vger.kernel.org Subject: Re: [Lse-tech] Re: RFC: patch to allow lock-free traversal of lists with insertion Message-ID: <20011010092300.A8389@hq2> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3BC3E424.1070901@wipro.com> User-Agent: Mutt/1.3.18i Organization: FSM Labs Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 10, 2001 at 11:31:08AM +0530, BALBIR SINGH wrote: > Linus Torvalds wrote: > >I can't think of many lists like that. The PCI lists certainly are both > >add/remove: cardbus bridges and hotplug-PCI means that they are not just > >purely "enumerate at bootup". > > > > I agree, I just thought of one case quickly. Assume that somebody did a cat /proc/pci. > Meanwhile somebody is adding a new pci device (hotplug PCI) simultaneously (which is very rare). > I would not care if the new device showed up in the output of /proc/pci this time. It would > definitely show up next time. Meanwhile locking the list (just in case it changes) is an > overhead in the case above. I was referring to these cases in my earlier mail. So you make the data structure and algorithms more complex and hard to maintain in order to get an undetectable improvement in the speed of something that almost never happens and and that is not even in the same neighborhood as being a bottleneck? - 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/