From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422819AbcFHHfa (ORCPT ); Wed, 8 Jun 2016 03:35:30 -0400 Received: from szxga01-in.huawei.com ([58.251.152.64]:8317 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751472AbcFHHf1 (ORCPT ); Wed, 8 Jun 2016 03:35:27 -0400 Subject: Re: [PATCH v9 00/14] Add support for remote unwind To: Arnaldo Carvalho de Melo , Jiri Olsa References: <1464924803-22214-1-git-send-email-hekuang@huawei.com> <20160603070629.GB23006@krava> <20160607194426.GF11589@kernel.org> CC: , , , , , , , , , , , , , , , From: Hekuang Message-ID: <5757CA42.4040703@huawei.com> Date: Wed, 8 Jun 2016 15:33:22 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <20160607194426.GF11589@kernel.org> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.110.55.166] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A090205.5757CA57.00D2,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: a5e22b8f8141bf2dfca5f2992198fa4e Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org hi 在 2016/6/8 3:44, Arnaldo Carvalho de Melo 写道: > Em Fri, Jun 03, 2016 at 09:06:29AM +0200, Jiri Olsa escreveu: >> On Fri, Jun 03, 2016 at 03:33:09AM +0000, He Kuang wrote: >> >> SNIP >> >>> For using remote libunwind libraries, reference this: >>> http://thread.gmane.org/gmane.linux.kernel/2224430 >>> >>> and now we can use LIBUNWIND_DIR to specific custom dirctories >>> containing libunwind libs. >>> >>> Acked-by: Jiri Olsa for most patches except: >>> >>> v9: >>> - Change function unwind__register_ops() to static. >>> - Move up unwind__prepare_access() in thread__insert_map() and save >>> map_groups__remove() call. >>> - Enclose multiple line if/else into braces. >>> - Fix miss modified function declaration for unwind__prepare_access() >>> in patch 10. >> for patchset: >> >> Acked-by: Jiri Olsa > Ok, I'm applying it, after fixing 'perf test unwind', 'perf top --call-graph dwarf' > and 'perf trace --call-graph dwarf', but I have one question, is the > scenario where we collect on a x86_64 machine and want to do analysis on > a ARM64 or x86-32 machine supported? This should be the odd case now, Yes, it's supported. But I never tested this before, so I just compiled libunwind for aarch64, and tested unwinding i686 perf.data on aarch64. Then I found another issue I've considered but missed at some version of this patch series. In util/unwind-libunwind-local.c, PERF_REG_SP/IP is used, but those macros are assigned to the host platform, we should redefine them in the wrapper file, for example in "util/libunwind/x86_32.c". After fixing this problem, i686 perf.data can be parsed on aarch64 machine. Since you've already applied the v9 patches, should I send patches based on the lastest tree as bug fixes or just update v9 patches? Thank you. Here is the modified part: diff --git a/tools/perf/util/libunwind/arm64.c b/tools/perf/util/libunwind/arm64.c index 4fb5395..8a5c2fc 100644 --- a/tools/perf/util/libunwind/arm64.c +++ b/tools/perf/util/libunwind/arm64.c @@ -29,6 +29,11 @@ #ifdef NO_LIBUNWIND_DEBUG_FRAME_AARCH64 #define NO_LIBUNWIND_DEBUG_FRAME #endif + +#undef PERF_REG_IP +#undef PERF_REG_SP +#define PERF_REG_IP PERF_REG_ARM64_PC +#define PERF_REG_SP PERF_REG_ARM64_SP #include "util/unwind-libunwind-local.c" struct unwind_libunwind_ops * diff --git a/tools/perf/util/libunwind/x86_32.c b/tools/perf/util/libunwind/x86_32.c index d98c17e..de21a39 100644 --- a/tools/perf/util/libunwind/x86_32.c +++ b/tools/perf/util/libunwind/x86_32.c @@ -31,6 +31,11 @@ #ifndef NO_LIBUNWIND_DEBUG_FRAME #define NO_LIBUNWIND_DEBUG_FRAME #endif + +#undef PERF_REG_IP +#undef PERF_REG_SP +#define PERF_REG_IP PERF_REG_X86_IP +#define PERF_REG_SP PERF_REG_X86_SP #include "util/unwind-libunwind-local.c" struct unwind_libunwind_ops * > but from a quick look I couldn't see this as being supported, is that > true or I was just lazy not to have tried this? > > - Arnaldo