Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750884Ab3IXMDt (ORCPT ); Tue, 24 Sep 2013 08:03:49 -0400 Received: from mail-vb0-f42.google.com ([209.85.212.42]:52836 "EHLO mail-vb0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750713Ab3IXMDs (ORCPT ); Tue, 24 Sep 2013 08:03:48 -0400 MIME-Version: 1.0 In-Reply-To: <20130924100620.GG15119@mudshark.cambridge.arm.com> References: <1379323053-11458-1-git-send-email-jean.pihet@linaro.org> <1379323053-11458-4-git-send-email-jean.pihet@linaro.org> <20130917102904.GA27258@mudshark.cambridge.arm.com> <20130924093450.GB1008@krava.brq.redhat.com> <20130924100620.GG15119@mudshark.cambridge.arm.com> Date: Tue, 24 Sep 2013 14:03:47 +0200 Message-ID: Subject: Re: [PATCH 3/4] perf tools: Check libunwind for availability of dwarf parsing feature From: Jean Pihet To: Will Deacon , Jiri Olsa Cc: Ingo Molnar , Arnaldo Carvalho de Melo , "linux-kernel@vger.kernel.org" , "linaro-kernel@lists.linaro.org" , "linux-arm-kernel@lists.infradead.org" , "patches@linaro.org" Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1621 Lines: 44 Hi Jiri, Will, On 24 September 2013 12:06, Will Deacon wrote: > On Tue, Sep 24, 2013 at 10:34:50AM +0100, Jiri Olsa wrote: >> On Tue, Sep 24, 2013 at 10:55:32AM +0200, Jean Pihet wrote: >> > Ping on the series. The two patches above (3/4 and 4/4) are generic >> > while the two others are impacting ARM only. >> > Is it possible to get an Ack for the generic ones? >> >> I'm fine with those changes.. still I'm sort of worried about >> current DWARF unwind users (but not sure if there're any), >> who depends on packaged libunwind compiled without >> --enable-debug-frame option. > > Since x86 is the only architecture using libunwind with perf at the moment, > and I'd expect it to use .eh_frame for unwinding, I'm also not sure there > are any existing users to worry about. Right > >> I've seen your libunwind patch to make it default, but >> not sure if it was accepted.. if not, maybe we should >> detect this and build that code conditionaly. > > It certainly defaults to "on" for ARM, but other architectures have to > enable it explicitly afaict. Yes that is correct. This patch (3/4) detects if the debug frame code is enabled in libunwind and uses the lib only if it is the case. Users that want the feature have to enable it explicitly; the commit description documents how to do that. So I think we are safe here. > > Will Thanks, Jean -- 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/