From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266175AbUGZXBe (ORCPT ); Mon, 26 Jul 2004 19:01:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266161AbUGZXAr (ORCPT ); Mon, 26 Jul 2004 19:00:47 -0400 Received: from waste.org ([209.173.204.2]:36754 "EHLO waste.org") by vger.kernel.org with ESMTP id S266158AbUGZXAd (ORCPT ); Mon, 26 Jul 2004 19:00:33 -0400 Date: Mon, 26 Jul 2004 18:00:04 -0500 From: Matt Mackall To: Andrew Morton Cc: "Perez-Gonzalez, Inaky" , cw@f00f.org, rml@ximian.com, linux-kernel@vger.kernel.org Subject: Re: [patch] kernel events layer Message-ID: <20040726230003.GS5414@waste.org> References: <20040725230951.0e150dbe.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040725230951.0e150dbe.akpm@osdl.org> User-Agent: Mutt/1.3.28i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jul 25, 2004 at 11:09:51PM -0700, Andrew Morton wrote: > "Perez-Gonzalez, Inaky" wrote: > > > > If you guys are up to it, I volunteer to write/port such a tool to scan > > out the send_kevent{_atomic,}()s and make a catalog out of it. > > I must say that my gut feeling here is that bolting an arbitrary new > namespace into the kernel in this manner is not the way to proceed. An uncontrolled namespace is no better than the existing printk info, IMO. And I think it's next to impossible to control the kevent namespace if it's scattered across the tree as strings, having tried to do something analogous for another large project. > I hope we'll hear more from Greg on this next week - see if we can come up > with some way to use the kobject/sysfs namespace for this. An API that looks like sysfs + dnotify to userspace is almost what you want. While the sysfs namespace has some of the problems above, we're already stuck with it. > Although heaven knows how "tmpfs just ran out of space" would map onto > kobject/sysfs. Per mountpoint sysfs trees? I'm sure there are lifetime issues there. Btw, we probably already have potential issues with kevents being stale by the time userspace picks them up - eth0 up, eth0 down, eth1 renamed eth0, userspace notices eth0 up, tries to config downed eth1. -- Mathematics is the supreme nostalgia of our time.