Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753044Ab2EUGDJ (ORCPT ); Mon, 21 May 2012 02:03:09 -0400 Received: from LGEMRELSE6Q.lge.com ([156.147.1.121]:54076 "EHLO LGEMRELSE6Q.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752460Ab2EUGDH (ORCPT ); Mon, 21 May 2012 02:03:07 -0400 X-AuditID: 9c930179-b7bb9ae000000ea5-76-4fb9da9649cd From: Namhyung Kim To: Arnaldo Carvalho de Melo Cc: Peter Zijlstra , Paul Mackerras , Ingo Molnar , LKML , David Ahern , Stephane Eranian , Jiri Olsa Subject: Re: [RFC 0/5] perf tools: Minimalistic build without libelf dependency References: <1336979424-17206-1-git-send-email-namhyung.kim@lge.com> Date: Mon, 21 May 2012 15:00:55 +0900 In-Reply-To: <1336979424-17206-1-git-send-email-namhyung.kim@lge.com> (Namhyung Kim's message of "Mon, 14 May 2012 16:10:19 +0900") Message-ID: <87mx522huw.fsf@sejong.aot.lge.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.0.95 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4078 Lines: 96 Hi, all Any other comments for this? Thanks, Namhyung On Mon, 14 May 2012 16:10:19 +0900, Namhyung Kim wrote: > NOTE: This is a RFC patchset and it contains a lot of rough edges > and ugly codes. > > Current build procedure of perf tools requires a couple of external > libraries. Although most of them are optional, elfutils' libelf is > mandatory for resolving symbols and build-id of the binaries being > profiled. For some reason, it makes embedded guys' life harder who > want to build and run perf tools on their boards. > > This patch set tries to fix the problem by letting the perf could > be built without libelf. The initial intent was just providing > perf record command to gather performance events interested on the > system and copies the data to development box to be used by perf > report for analysis. > > However it's changed to have most of perf commands as is because > perf can resolve kernel symbols without libelf and many of perf > commands deal (mostly) with kernel events - so no need to restrict > capability of perf tools. Therefore, the end result is not so > minimalistic in fact and only thing it cannot do is "perf probe". > > And then I realized that the perf record needs to know about the > build-id's anyway :(. So I implemented a poor man's version of elf > parser only for parsing the build-id info. > > To build a minimal perf tools, pass MINIMAL=1 to make. The perf > report will not display symbol names: > > # Samples: 988 of event 'cycles' > # Event count (approx.): 3726465542 > # > # Overhead Command Shared Object Symbol > # ........ ....... ................. ......................... > # > 98.40% noploop noploop [.] 0x000000000000066d > 1.35% noploop ld-2.15.so [.] 0x000000000000bab1 > 0.10% noploop [kernel.kallsyms] [k] native_write_msr_safe > 0.10% noploop [kernel.kallsyms] [k] scheduler_tick > 0.03% noploop [kernel.kallsyms] [k] bad_range > 0.01% noploop [kernel.kallsyms] [k] pipe_read > > But perf buildid-list can show you the build-id's: > > $ ./perf buildid-list > ebfc1bdb98999c64d36ddfe394c58df3de6cbcfb [kernel.kallsyms] > 52f0c5f25b95075e6fd7682763f7c3a779a4e889 /usr/lib64/ld-2.15.so > 43a7a2b399b6ee2ff29c6bdadbda6bff88712ed4 /home/namhyung/bin/noploop > > So it can be packed using perf archive so copied and analized > with full-fledged perf tools on a development machine. > > This patchset is based on commit cb04ff9ac424 ("sched, perf: Use > a single callback into the scheduler") and tested on x86_64 and arm. > > Any comments are welcome, thanks. > Namhyung > > > Namhyung Kim (5): > perf symbols: Introduce symbol__elf_init() > perf symbols: Do not use ELF's symbol binding constants > perf tools: Split out util/symbol-elf.c > perf tools: Support minimal build > perf symbols: Implement poor man's ELF parser > > tools/perf/Makefile | 29 ++ > tools/perf/builtin-buildid-list.c | 4 +- > tools/perf/builtin-top.c | 5 +- > tools/perf/command-list.txt | 2 +- > tools/perf/perf.c | 2 + > tools/perf/ui/browsers/map.c | 5 +- > tools/perf/util/elf-minimal.h | 153 ++++++++ > tools/perf/util/generate-cmdlist.sh | 15 + > tools/perf/util/symbol-elf.c | 691 +++++++++++++++++++++++++++++++++ > tools/perf/util/symbol-minimal.c | 258 +++++++++++++ > tools/perf/util/symbol.c | 712 ++--------------------------------- > tools/perf/util/symbol.h | 20 + > 12 files changed, 1195 insertions(+), 701 deletions(-) > create mode 100644 tools/perf/util/elf-minimal.h > create mode 100644 tools/perf/util/symbol-elf.c > create mode 100644 tools/perf/util/symbol-minimal.c -- 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/