From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 6 Feb 2002 18:45:18 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 6 Feb 2002 18:45:04 -0500 Received: from e21.nc.us.ibm.com ([32.97.136.227]:3054 "EHLO e21.nc.us.ibm.com") by vger.kernel.org with ESMTP id ; Wed, 6 Feb 2002 18:44:15 -0500 Message-ID: <3C61BFC9.8030905@us.ibm.com> Date: Wed, 06 Feb 2002 15:44:09 -0800 From: Dave Hansen User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.8) Gecko/20020205 X-Accept-Language: en-us MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: [PATCH] Removal of big kernel lock from isdn drivers Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org I've been examining the continuing additions of the big kernel lock (BKL) to the 2.5 tree. I noticed that in 2.5.3, the ISDN subsystem added the BKL to several places. In response to this, I have written several patches to attempt removal of the BKL from the ISDN subsystem. I have little knowledge of the drivers themselves, so I would like some assistance from those of you who understand them better. I probably have an over-simplified view of the code, so my patches may be too simplistic. They're a bit big, so I've made them available here: http://www.sr71.net/ibm/isdn/ isdn.bkl-remove.ippp_lock.patch: http://www.sr71.net/ibm/isdn/isdn.bkl-remove.isdn_dev_sem.patch added ippp_lock to ippp_struct * It appeared that the BKL was being used to guard the file struct's private data field, which is a ippp_struct. I added a semaphore to that structure which can be locked instead of the BKL. isdn.bkl-remove.hydsn_cards_sem.patch: http://www.sr71.net/ibm/isdn/isdn.bkl-remove.hydsn_cards_sem.patch adds rwsemaphore hydsn_cards_sem * hydsn_cards_sem guards the card_root list. It is a read/write semaphore which must be held for write when modifying the list. isdn.bkl-remove.isdn_dev_rwsem.patch: http://www.sr71.net/ibm/isdn/isdn.bkl-remove.ppp_lock.patch * changes name of "dev" to "isdn_dev" - If there are going to be global variables, they can at least not have exceedingly generic names like "dev"! * adds global isdn_dev_rwsem - isdn_dev_rwsem must be held when manipulating "isdn_dev" I know that these patches should probably be separate, but this is easier for me. -- Dave Hansen haveblue@us.ibm.com