Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261868AbTEHQyv (ORCPT ); Thu, 8 May 2003 12:54:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261878AbTEHQyv (ORCPT ); Thu, 8 May 2003 12:54:51 -0400 Received: from meg.hrz.tu-chemnitz.de ([134.109.132.57]:1999 "EHLO meg.hrz.tu-chemnitz.de") by vger.kernel.org with ESMTP id S261868AbTEHQys (ORCPT ); Thu, 8 May 2003 12:54:48 -0400 Date: Thu, 8 May 2003 17:36:47 +0200 From: Ingo Oeser To: William Lee Irwin III , Torsten Landschoff , J?rn Engel , Linux kernel Subject: Re: top stack (l)users for 2.5.69 Message-ID: <20030508173647.W626@nightmaster.csn.tu-chemnitz.de> References: <20030507132024.GB18177@wohnheim.fh-wedel.de> <20030507135657.GC18177@wohnheim.fh-wedel.de> <20030507143315.GA6879@stargate.galaxy> <20030507144736.GE8978@holomorphy.com> <20030507150429.GA7248@stargate.galaxy> <20030507160144.GS8931@holomorphy.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2i In-Reply-To: <20030507160144.GS8931@holomorphy.com>; from wli@holomorphy.com on Wed, May 07, 2003 at 09:01:44AM -0700 X-Spam-Score: -32.5 (--------------------------------) X-Scanner: exiscan for exim4 (http://duncanthrax.net/exiscan/) *19Dorb-0004Os-00*X8gTAVipnm2* Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1498 Lines: 33 On Wed, May 07, 2003 at 09:01:44AM -0700, William Lee Irwin III wrote: > Pure per-cpu stacks would require the interrupt model of programming to > be used, which is a design decision deep enough it's debatable whether > it's feasible to do conversions to or from at all, never mind desirable. > Basically every entry point into the kernel is treated as an interrupt, > and nothing can ever sleep or be scheduled in the kernel, but rather > only register callbacks to be run when the event waited for occurs. > Scheduling only happens as a decision of which userspace task to resume > when returning from the kernel to userspace, though one could envision > a priority queue discipline for processing the registered callbacks. To illustrate that: It's basically a difference like between fork() and spawn(). Threads (of control) are completely decoupled und re-coupled only by the event/callback mechanism. This is introducing exactly the mechanisms Linus didn't like when he decided, that he doesn't want a micro kernel architecture. So it is not going to happen RSN. Regards Ingo Oeser -- Marketing ist die Kunst, Leuten Sachen zu verkaufen, die sie nicht brauchen, mit Geld, was sie nicht haben, um Leute zu beeindrucken, die sie nicht moegen. - 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/