From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932073AbWERMBE (ORCPT ); Thu, 18 May 2006 08:01:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750737AbWERMBD (ORCPT ); Thu, 18 May 2006 08:01:03 -0400 Received: from public.id2-vpn.continvity.gns.novell.com ([195.33.99.129]:11700 "EHLO emea1-mh.id2.novell.com") by vger.kernel.org with ESMTP id S1750869AbWERMBB (ORCPT ); Thu, 18 May 2006 08:01:01 -0400 Message-Id: <446C7E61.76E4.0078.0@novell.com> X-Mailer: Novell GroupWise Internet Agent 7.0.1 Beta Date: Thu, 18 May 2006 14:02:09 +0200 From: "Jan Beulich" To: "Andi Kleen" Cc: , Subject: Re: [discuss] Re: [PATCH 2/3] reliable stack trace support (x86-64) References: <4469FC22.76E4.0078.0@novell.com> <200605161905.11907.ak@suse.de> <446C5C6E.76E4.0078.0@novell.com> <200605181220.46037.ak@suse.de> In-Reply-To: <200605181220.46037.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org >Three instructions? We might be still able to afford that. > >push/pop is probably not needed because the stack frame will be already >set up (ok possibly after a few instructions, but a small window might be >tolerable) Okay, then I'll prepare a patch to that effect during the next couple of days. >Maybe I'm dense but I still don't get - frame has a pt_regs so why >isn't the caller allowed to know about that fact? Because the fact that there is a regs fields and the PC is accessible through it is architecture specific, yet the caller (kernel/unwind.c) ought to be architecture independent. Jan