From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 4 Jun 2001 15:28:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 4 Jun 2001 15:28:41 -0400 Received: from tomts13.bellnexxia.net ([209.226.175.34]:8433 "EHLO tomts13-srv.bellnexxia.net") by vger.kernel.org with ESMTP id ; Mon, 4 Jun 2001 15:28:23 -0400 To: Richard Gooch Cc: aki.jain@stanford.edu (Akash Jain), linux-kernel@vger.kernel.org, su.class.cs99q@nntp.stanford.edu Subject: Re: [PATCH] fs/devfs/base.c In-Reply-To: <200106040707.f5477ET11421@vindaloo.ras.ucalgary.ca> From: Bill Pringlemeir Date: 04 Jun 2001 15:26:25 -0400 In-Reply-To: Richard Gooch's message of "Mon, 4 Jun 2001 01:07:14 -0600" Message-ID: User-Agent: Gnus/5.0803 (Gnus v5.8.3) Emacs/20.4 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org >>>>> "Richard" == Richard Gooch writes: [snip] > I guess we should ask the question as to what's an > acceptable usage. Theoretically, any amount could pose a > problem, but that's hardly a useful position to work There was a discussion on comp.arch.embedded about bounded stack use. It is fairly easy to calculate the stack usage for call trees, but much more difficult for `DAGs'. Ie, a recursive functions etc. I don't know about the policy on recursion in the kernel, but I think it would be bad. Perhaps the checker could be modified to keep track of the call tree and find the largest value used in the tree. Each function will have a maximum, to which you should add the interrupt handling overhead, which would be calculated in a similar way. This will work if you do not allow re-entrant interrupts and you do not have any `cycles' in the function call hierarchies. hth, Bill Pringlemeir.