From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267316AbUHSTaU (ORCPT ); Thu, 19 Aug 2004 15:30:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267311AbUHSTaU (ORCPT ); Thu, 19 Aug 2004 15:30:20 -0400 Received: from sccrmhc11.comcast.net ([204.127.202.55]:36309 "EHLO sccrmhc11.comcast.net") by vger.kernel.org with ESMTP id S267306AbUHST15 (ORCPT ); Thu, 19 Aug 2004 15:27:57 -0400 Message-ID: <4124FF3C.6080108@acm.org> Date: Thu, 19 Aug 2004 14:27:56 -0500 From: Corey Minyard User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.2) Gecko/20040803 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Andreas Dilger Cc: lkml Subject: Re: Patch to 2.6.8.1-mm2 to allow multiple NMI handlers to be registered References: <4124BACB.30100@acm.org> <20040819164049.GS8967@schnapps.adilger.int> In-Reply-To: <20040819164049.GS8967@schnapps.adilger.int> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andreas Dilger wrote: >On Aug 19, 2004 09:35 -0500, Corey Minyard wrote: > > >>* Allow multiple handlers to be registered and return if they have >>handled the NMI or not. oprofile and nmi_watchdog are modified to use this. >> >> > >Why not use a notifier call chain as is done with panic & friends instead >of implementing the same thing specifically for NMI? > > > A couple of reasons: * The "handled" value needs to be passed around so handler know if previous handlers have already handled the NMI. * It allows the list of registered NMI handlers to be dumped in /proc/interrupts I thought that the notifiers callout used locks (which would be a no-go), but it doesn't. So I can scratch that one from my list. Thanks, -Corey