Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756242Ab0DNQ7t (ORCPT ); Wed, 14 Apr 2010 12:59:49 -0400 Received: from mtagate1.de.ibm.com ([195.212.17.161]:50092 "EHLO mtagate1.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756186Ab0DNQ7r (ORCPT ); Wed, 14 Apr 2010 12:59:47 -0400 Date: Wed, 14 Apr 2010 19:00:08 +0200 From: Heiko Carstens To: Masami Hiramatsu Cc: Ian Munsie , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, benh@kernel.crashing.org, Peter Zijlstra , Paul Mackerras , Ingo Molnar , Arnaldo Carvalho de Melo , Frederic Weisbecker Subject: Re: [PATCH v2 1/2] perf: Move arch specific code into separate arch directory Message-ID: <20100414170008.GA2359@osiris.boeblingen.de.ibm.com> References: <1271221600-25533-1-git-send-email-imunsie@au.ibm.com> <1271221600-25533-2-git-send-email-imunsie@au.ibm.com> <4BC5D534.8010508@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4BC5D534.8010508@redhat.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2207 Lines: 41 On Wed, Apr 14, 2010 at 07:46:12AM -0700, Masami Hiramatsu wrote: > Ian Munsie wrote: > > From: Ian Munsie > > > > The perf userspace tool included some architecture specific code to map > > registers from the DWARF register number into the names used by the regs > > and stack access API. > > > > This patch moves the architecture specific code out into a separate > > arch/x86 directory along with the infrastructure required to use it. > > > > Signed-off-by: Ian Munsie > > --- > > Changes since v1: From Masami Hiramatsu's suggestion, I added a check in the > > Makefile for if the arch specific Makefile defines PERF_HAVE_DWARF_REGS, > > printing a message during build if it has not. This simplifies the code > > removing the odd macro from the previous version and the need for an arch > > specific arch_dwarf-regs.h. I have not entirely disabled DWARF support for > > architectures that don't implement the register mappings, so that they can > > still add a probe based on a line number (they will be missing the ability to > > capture the value of a variable from a register). > > Hmm, sorry, I don't think it is a good way to go... IMHO, porting dwarf-regs.c > is so easy (you can just refer systemtap/runtime/loc2c-runtime.h), easier > than porting kprobe-tracer on another arch. And perf is a part of kernel tree. > It means that someone who are porting kprobe-tracer, he should port > dwarf-regs.c too. In that case, PERF_HAVE_DWARF_REGS flag will be used only > between those two patches in same patchset. So, I suggested you to drop dwarf > support if dwarf-regs mapping doesn't exist. > > AFAIK, at this point, only s390 users are affected. I'd like to ask > them to just port a register mapping on perf and test it too. Hm, I'm a bit lost here. Probably due to lack of context. What would be missing on s390 and what am I supposed to implement and how can I test it? Any pointers to git commits? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/