From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755099AbYJZN3m (ORCPT ); Sun, 26 Oct 2008 09:29:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753458AbYJZN3e (ORCPT ); Sun, 26 Oct 2008 09:29:34 -0400 Received: from viefep18-int.chello.at ([213.46.255.22]:6992 "EHLO viefep18-int.chello.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753024AbYJZN3d (ORCPT ); Sun, 26 Oct 2008 09:29:33 -0400 X-SourceIP: 213.46.9.244 Subject: Re: [PATCH 1/4] Add support for userspace stacktraces in tracing/iter_ctrl From: Peter Zijlstra To: "Frank Ch. Eigler" Cc: fweisbec@gmail.com, =?ISO-8859-1?Q?T=F6r=F6k?= Edwin , mingo@elte.hu, srostedt@redhat.com, sandmann@daimi.au.dk, linux-kernel@vger.kernel.org In-Reply-To: References: <1223817124-27239-1-git-send-email-edwintorok@gmail.com> <1223817124-27239-3-git-send-email-edwintorok@gmail.com> Content-Type: text/plain Date: Sun, 26 Oct 2008 14:29:42 +0100 Message-Id: <1225027782.32713.10.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.24.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2008-10-26 at 09:15 -0400, Frank Ch. Eigler wrote: > "=?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?=" writes: > > > [...] > >> +/* Userspace stacktrace - based on kernel/trace/trace_sysprof.c */ > >> + > >> +struct stack_frame { > >> + const void __user *next_fp; > >> + unsigned long return_address; > >> +}; > > [...] > > To what extent does this actually work, and on which architectures? > While the kernel appears willing to sacrifice some performance for > functionality by building with frame pointers at the drop of a tracing > hat, userspace is not like that. Aww, common, Gentoo is brilliant for that :-) CFLAGS+=-fframe-pointer emerge -uDNe world Then again, you'd better not have all that desktop bloat installed, otherwise that will take ages.. KDE/OOo compile times anyone? /me runs