Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752511Ab3IFOKp (ORCPT ); Fri, 6 Sep 2013 10:10:45 -0400 Received: from mail-ve0-f170.google.com ([209.85.128.170]:51827 "EHLO mail-ve0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751771Ab3IFOKn (ORCPT ); Fri, 6 Sep 2013 10:10:43 -0400 MIME-Version: 1.0 In-Reply-To: <20130906101720.GA1055@krava.brq.redhat.com> References: <1378317854-25965-1-git-send-email-jean.pihet@linaro.org> <1378317854-25965-4-git-send-email-jean.pihet@linaro.org> <20130905163030.GF1100@krava.brq.redhat.com> <20130906101720.GA1055@krava.brq.redhat.com> Date: Fri, 6 Sep 2013 16:10:41 +0200 Message-ID: Subject: Re: [PATCH 3/3] perf: parse the .debug_frame section in case .eh_frame is not present From: Jean Pihet To: Jiri Olsa Cc: Will Deacon , "linux-kernel@vger.kernel.org" , "linaro-kernel@lists.linaro.org" , "linux-arm-kernel@lists.infradead.org" , Patch Tracking 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: 2835 Lines: 85 On 6 September 2013 12:17, Jiri Olsa wrote: > On Fri, Sep 06, 2013 at 11:31:17AM +0200, Jean Pihet wrote: >> Hi Jiri, >> >> On 5 September 2013 18:30, Jiri Olsa wrote: >> > On Wed, Sep 04, 2013 at 08:04:14PM +0200, Jean Pihet wrote: >> >> On ARM the debug info is not present in the .eh_frame sections but >> >> instead in .debug_frame. >> >> Use libunwind to load and parse the debug info. >> > >> > hum, cannot make final link: >> > >> > $ make LIBUNWIND_DIR=/opt/libunwind/ >> > CHK -fstack-protector-all >> > CHK -Wstack-protector >> > CHK -Wvolatile-register-var >> > CHK -D_FORTIFY_SOURCE=2 >> > CHK bionic >> > CHK libelf >> > CHK libdw >> > CHK -DLIBELF_MMAP >> > CHK -DLIBELF_MMAP >> > CHK libunwind >> > CHK libaudit >> > >> > ... >> > >> > make[1]: `liblk.a' is up to date. >> > SUBDIR /home/jolsa/linux-perf/tools/lib/traceevent/ >> > LINK perf >> > libperf.a(unwind.o): In function `find_proc_info': >> > /home/jolsa/linux-perf/tools/perf/util/unwind.c:339: undefined reference to `_Ux86_64_dwarf_find_debug_frame' >> > collect2: ld returned 1 exit status >> > make: *** [perf] Error 1 >> > >> > >> > I'm using the latest code from git://git.sv.gnu.org/libunwind.git >> > >> > Looks like dwarf_find_debug_frame is not exported, although >> > it looks like it is based on what I see in libunwind sources ;-) >> > >> > What did I miss? >> libunwind needs to be configured with --enable-debug-frame for the >> debug_frame code to be included in the lib. >> On ARM the flag is always set while it isn't on x86. Here is the >> culprit below (lines from libunwind configure). > > yay, thats it! > >> >> Should that be changed in configure along with the changes in tools/perf? > > I guess it's ok I wonder how to express the dependency between the perf changes and the libunwind version and configure flags. Is a note in the commit descritpion enough? I fear that the change can break many build systems... > > Other than that tabs misformating the 'perf tool' change looks ok. Ok I will respin the code with the typo and formatting changes. > > I tested the '.eh_frame' code and it's still working. Once > I figure out how to create a x86 binary with .debug_frame > data I'll test the code itself ;-) Great! > > If you could think of any automated testcase for this that could > be added under 'tests' that'd be nice (not necessarily) Ok will look at it. Linaro has automated tests that I need to write as well so rather do it in perf/tests directly ;-p > > thanks, > jirka 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/