From patchwork Mon Dec 5 04:41:03 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wang Nan X-Patchwork-Id: 86494 Delivered-To: patch@linaro.org Received: by 10.140.20.101 with SMTP id 92csp1305800qgi; Sun, 4 Dec 2016 20:42:32 -0800 (PST) X-Received: by 10.99.126.94 with SMTP id o30mr99416413pgn.66.1480912951940; Sun, 04 Dec 2016 20:42:31 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id k1si13235138plb.309.2016.12.04.20.42.31; Sun, 04 Dec 2016 20:42:31 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751577AbcLEEm2 (ORCPT + 25 others); Sun, 4 Dec 2016 23:42:28 -0500 Received: from szxga01-in.huawei.com ([58.251.152.64]:6720 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751320AbcLEEm0 (ORCPT ); Sun, 4 Dec 2016 23:42:26 -0500 Received: from 172.24.1.36 (EHLO szxeml422-hub.china.huawei.com) ([172.24.1.36]) by szxrg01-dlp.huawei.com (MOS 4.3.7-GA FastPath queued) with ESMTP id DWB74156; Mon, 05 Dec 2016 12:41:23 +0800 (CST) Received: from [127.0.0.1] (10.111.66.109) by szxeml422-hub.china.huawei.com (10.82.67.152) with Microsoft SMTP Server id 14.3.235.1; Mon, 5 Dec 2016 12:41:11 +0800 Subject: Re: [PATCH v3 10/30] perf clang: Add builtin clang support ant test case To: Arnaldo Carvalho de Melo , References: <20161126070354.141764-1-wangnan0@huawei.com> <20161126070354.141764-11-wangnan0@huawei.com> <20161202154440.GB5931@redhat.com> <5844D292.3000506@huawei.com> CC: , , Ingo Molnar , , , , Jiri Olsa , From: "Wangnan (F)" Message-ID: <5844EFDF.4040801@huawei.com> Date: Mon, 5 Dec 2016 12:41:03 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.0 MIME-Version: 1.0 In-Reply-To: <5844D292.3000506@huawei.com> X-Originating-IP: [10.111.66.109] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2016/12/5 10:36, Wangnan (F) wrote: > > > On 2016/12/2 23:44, Arnaldo Carvalho de Melo wrote: >> Em Sat, Nov 26, 2016 at 07:03:34AM +0000, Wang Nan escreveu: >>> Add basic clang support in clang.cpp and test__clang() testcase. The >>> first testcase checks if builtin clang is able to generate LLVM IR. >>> >>> tests/clang.c is a proxy. Real testcase resides in >>> utils/c++/clang-test.cpp in c++ and exports C interface to perf test >>> subsystem. >>> >>> Test result: >>> >>> $ perf test -v clang >>> 51: Test builtin clang support : >>> 51.1: Test builtin clang compile C source to IR : >>> --- start --- >>> test child forked, pid 13215 >>> test child finished with 0 >>> ---- end ---- >>> Test builtin clang support subtest 0: Ok >> While testing this I noticed that the perf binary got huge, can't this >> be done in some other way, i.e. using dynamic library? > > I intentionally use statically linking because it is good for > smartphone: we can simply 'adb push' a statically linked perf > to Android. > > The resulting ELF executable would be even larger if LLVM is > built with default setting. > > In my setting the resuling 'perf' is less than 60MB: > > $ ls -s ~/perf -h > 58M /home/wn/perf > > $ size ~/perf > text data bss dec hex filename > 56931273 2950808 24108632 83990713 50198b9 /home/wn/perf > > It is reasonable for me. > > I think using dynamic clang and llvm libraries is possible but I > never tried it before. It depend on LLVM compiling. I think if > distro provides shared libraries then perf can utilize them > automatically. Let me check it today. > Good news: it works. To enable llvm and clang dynamic libraries, we need to build llvm and clang with cmake option -DBUILD_SHARED_LIBS=ON. Then apply a trivial patch to perf: LIBS += -Wl,--start-group $(LIBCLANG) -Wl,--end-group endif (replace '.a' to '.so') Resuling perf executable: $ ls -s -h ~/perf 26M /home/wn/perf $ size ~/perf text data bss dec hex filename 4274339 755032 23959984 28989355 1ba57ab /home/wn/perf $ strip ~/perf $ ls -s -h 4.9M /home/wn/perf $ ldd ~/perf | grep 'LLVM\|clang' libclangBasic.so => /tmp/oxygen_root/usr/lib64/libclangBasic.so (0x00007f24da49f000) libclangCodeGen.so => /tmp/oxygen_root/usr/lib64/libclangCodeGen.so (0x00007f24d9f72000) libclangFrontend.so => /tmp/oxygen_root/usr/lib64/libclangFrontend.so (0x00007f24d9c64000) libclangTooling.so => /tmp/oxygen_root/usr/lib64/libclangTooling.so (0x00007f24d9a01000) libLLVMBPFCodeGen.so => /tmp/oxygen_root/usr/lib64/libLLVMBPFCodeGen.so (0x00007f24d97e2000) libLLVMBPFDesc.so => /tmp/oxygen_root/usr/lib64/libLLVMBPFDesc.so (0x00007f24d95da000) .... As I said, if distro provides dynamic libraries then everything would be fine. If you are okay with the above conclusion, in next version I'll use '-lclangBasic' style linking options so it works for both dynamic and static LLVM/clang, then let's wait for distro's action. Thank you. diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf index dfb20dd..e3054f3 100644 --- a/tools/perf/Makefile.perf +++ b/tools/perf/Makefile.perf @@ -346,7 +346,7 @@ LIBS = -Wl,--whole-archive $(PERFLIBS) -Wl,--no-whole-archive -Wl,--start-group ifeq ($(USE_CLANG), 1) CLANGLIBS_LIST = AST Basic CodeGen Driver Frontend Lex Tooling Edit Sema Analysis Parse Serialization - LIBCLANG = $(foreach l,$(CLANGLIBS_LIST),$(wildcard $(shell $(LLVM_CONFIG) --libdir)/libclang$(l).a)) + LIBCLANG = $(foreach l,$(CLANGLIBS_LIST),$(wildcard $(shell $(LLVM_CONFIG) --libdir)/libclang$(l).so))