From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([66.187.233.31]:49582 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S964854AbWJCKB6 (ORCPT ); Tue, 3 Oct 2006 06:01:58 -0400 From: David Howells In-Reply-To: <20061002201836.GB31365@elte.hu> References: <20061002201836.GB31365@elte.hu> <20061002162049.17763.39576.stgit@warthog.cambridge.redhat.com> <20061002162053.17763.26032.stgit@warthog.cambridge.redhat.com> <20061002132116.2663d7a3.akpm@osdl.org> Subject: Re: [PATCH 3/3] IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Date: Tue, 03 Oct 2006 11:01:14 +0100 Message-ID: <10243.1159869674@warthog.cambridge.redhat.com> Sender: linux-arch-owner@vger.kernel.org To: Ingo Molnar Cc: Andrew Morton , David Howells , Thomas Gleixner , torvalds@osdl.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Dmitry Torokhov , Greg KH , David Brownell , Alan Stern List-ID: Ingo Molnar wrote: > i agree that we should do this in one go and in Linus' tree. I suspect > David has a script for this, so we can do it anytime for any tree, > right? I wish. No, it's not simple enough to script. All the usages of struct pt_regs have to be eyeballed and have to be poked with the compiler. The problem is when an interrupt handler passes regs down to someone else - that I can't find. However, I'm now in a position that I can just keep pulling Linus's GIT tree with StGIT and fixing up the wibbly bits and grepping for new instances of pt_regs and of course compile testing on a bunch of arches for which I have compilers. > the amount of code that truly relies on regs being present is very low. The same goes for the IRQ number itself too. Very few things actually use that, mostly they just use the arbitrary data argument. I'm not sure we want to do the same to that, though, since it makes cascaded PIC processing more interesting as the IRQ number changes. David