From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751298AbWFUIsh (ORCPT ); Wed, 21 Jun 2006 04:48:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751299AbWFUIsh (ORCPT ); Wed, 21 Jun 2006 04:48:37 -0400 Received: from e2.ny.us.ibm.com ([32.97.182.142]:44214 "EHLO e2.ny.us.ibm.com") by vger.kernel.org with ESMTP id S1751298AbWFUIsg (ORCPT ); Wed, 21 Jun 2006 04:48:36 -0400 Subject: Re: [PATCH 00/11] Task watchers: Introduction From: Matt Helsley To: Andrew Morton Cc: LKML , Jes Sorensen , LSE , "Chandra S. Seetharaman" , Alan Stern , "John T. Kohl" , Balbir Singh , Shailabh Nagar In-Reply-To: <20060619032453.2c19e32c.akpm@osdl.org> References: <1150242721.21787.138.camel@stark> <20060619032453.2c19e32c.akpm@osdl.org> Content-Type: text/plain Date: Wed, 21 Jun 2006 01:35:29 -0700 Message-Id: <1150878929.21787.956.camel@stark> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2006-06-19 at 03:24 -0700, Andrew Morton wrote: > On Tue, 13 Jun 2006 16:52:01 -0700 > Matt Helsley wrote: > > > Task watchers is a notifier chain that sends notifications to registered > > callers whenever a task forks, execs, changes its [re][ug]id, or exits. > > Seems a reasonable objective - it'll certainly curtail (indeed, reverse) > the ongoing proliferation of little subsystem-specific hooks all over the > core code, will allow us to remove some #includes from core code and should > permit some more things to be loaded as modules. > > But I do wonder if it would have been better to have separate chains for > each of WATCH_TASK_INIT, WATCH_TASK_EXEC, WATCH_TASK_UID, WATCH_TASK_GID, > WATCH_TASK_EXIT. That would reduce the number of elements which need to be > traversed at each event and would eliminate the need for demultiplexing at > each handler. It's a good idea, and should have the advantages you cited. My only concern is that each task watcher would have to (un)register multiple notifier blocks. I expect that in most cases there would only be two. Also, if we apply this to per-task notifiers it would mean that we'd have a 6 raw notifier heads per-task. Would you like me to redo the patches as multiple chains? Alternately, I could produce patches that apply on top of the current set. Cheers, -Matt Helsley PS: I've already picked up your warning fix.