From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-20.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A51EC433DB for ; Wed, 20 Jan 2021 03:03:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3C6E52310D for ; Wed, 20 Jan 2021 03:03:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730751AbhATDCu (ORCPT ); Tue, 19 Jan 2021 22:02:50 -0500 Received: from mail.loongson.cn ([114.242.206.163]:55628 "EHLO loongson.cn" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730297AbhATCdM (ORCPT ); Tue, 19 Jan 2021 21:33:12 -0500 Received: from [10.130.0.135] (unknown [113.200.148.30]) by mail.loongson.cn (Coremail) with SMTP id AQAAf9Dx6L0ulgdgxeQHAA--.12601S3; Wed, 20 Jan 2021 10:32:15 +0800 (CST) Subject: Re: [PATCH bpf-next v2] samples/bpf: Update README.rst and Makefile for manually compiling LLVM and clang To: Fangrui Song References: <1611042978-21473-1-git-send-email-yangtiezhu@loongson.cn> <20210119215815.efyerbwwq5x2o26q@google.com> Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Nathan Chancellor , Nick Desaulniers , netdev@vger.kernel.org, bpf@vger.kernel.org, clang-built-linux@googlegroups.com, linux-kernel@vger.kernel.org, Xuefeng Li From: Tiezhu Yang Message-ID: Date: Wed, 20 Jan 2021 10:32:14 +0800 User-Agent: Mozilla/5.0 (X11; Linux mips64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <20210119215815.efyerbwwq5x2o26q@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CM-TRANSID: AQAAf9Dx6L0ulgdgxeQHAA--.12601S3 X-Coremail-Antispam: 1UD129KBjvJXoWxKrWfuFyUtr4rKFW5Zr1DJrb_yoW7Gw4Upr W7ta1SkrZ2qryfZFyxGw4UXw4rZ395Ja4UCa4xGryrZ3WDZrn7GF4ayrWfWFWUXr92yF47 Ar1rGa4DGF18Xa7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBY14x267AKxVW5JVWrJwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26ryj6F1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26F4j 6r4UJwA2z4x0Y4vEx4A2jsIE14v26r4UJVWxJr1l84ACjcxK6I8E87Iv6xkF7I0E14v26F 4UJVW0owAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv 7VC0I7IYx2IY67AKxVWUXVWUAwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r 1j6r4UM4x0Y48IcVAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628v n2kIc2xKxwCYjI0SjxkI62AI1cAE67vIY487MxkIecxEwVAFwVW8JwCF04k20xvY0x0EwI xGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480 Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2Ij64vIr41lIxAIcVC0I7 IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k2 6cxKx2IYs7xG6rW3Jr0E3s1lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x 0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7VUbXo7tUUUUU== X-CM-SenderInfo: p1dqw3xlh2x3gn0dqz5rrqw2lrqou0/ Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/20/2021 05:58 AM, Fangrui Song wrote: > On 2021-01-19, Tiezhu Yang wrote: >> The current llvm/clang build procedure in samples/bpf/README.rst is >> out of date. See below that the links are not accessible any more. >> >> $ git clone http://llvm.org/git/llvm.git >> Cloning into 'llvm'... >> fatal: unable to access 'http://llvm.org/git/llvm.git/': Maximum (20) >> redirects followed >> $ git clone --depth 1 http://llvm.org/git/clang.git >> Cloning into 'clang'... >> fatal: unable to access 'http://llvm.org/git/clang.git/': Maximum >> (20) redirects followed >> >> The llvm community has adopted new ways to build the compiler. There are >> different ways to build llvm/clang, the Clang Getting Started page >> [1] has >> one way. As Yonghong said, it is better to just copy the build procedure >> in Documentation/bpf/bpf_devel_QA.rst to keep consistent. >> >> I verified the procedure and it is proved to be feasible, so we should >> update README.rst to reflect the reality. At the same time, update the >> related comment in Makefile. >> >> [1] https://clang.llvm.org/get_started.html >> >> Signed-off-by: Tiezhu Yang >> Acked-by: Yonghong Song >> --- >> >> v2: Update the commit message suggested by Yonghong, >> thank you very much. >> >> samples/bpf/Makefile | 2 +- >> samples/bpf/README.rst | 17 ++++++++++------- >> 2 files changed, 11 insertions(+), 8 deletions(-) >> >> diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile >> index 26fc96c..d061446 100644 >> --- a/samples/bpf/Makefile >> +++ b/samples/bpf/Makefile >> @@ -208,7 +208,7 @@ TPROGLDLIBS_xdpsock += -pthread -lcap >> TPROGLDLIBS_xsk_fwd += -pthread >> >> # Allows pointing LLC/CLANG to a LLVM backend with bpf support, >> redefine on cmdline: >> -# make M=samples/bpf/ LLC=~/git/llvm/build/bin/llc >> CLANG=~/git/llvm/build/bin/clang >> +# make M=samples/bpf LLC=~/git/llvm-project/llvm/build/bin/llc >> CLANG=~/git/llvm-project/llvm/build/bin/clang >> LLC ?= llc >> CLANG ?= clang >> OPT ?= opt >> diff --git a/samples/bpf/README.rst b/samples/bpf/README.rst >> index dd34b2d..d1be438 100644 >> --- a/samples/bpf/README.rst >> +++ b/samples/bpf/README.rst >> @@ -65,17 +65,20 @@ To generate a smaller llc binary one can use:: >> Quick sniplet for manually compiling LLVM and clang >> (build dependencies are cmake and gcc-c++):: >> >> - $ git clone http://llvm.org/git/llvm.git >> - $ cd llvm/tools >> - $ git clone --depth 1 http://llvm.org/git/clang.git >> - $ cd ..; mkdir build; cd build >> - $ cmake .. -DLLVM_TARGETS_TO_BUILD="BPF;X86" >> - $ make -j $(getconf _NPROCESSORS_ONLN) >> + $ git clone https://github.com/llvm/llvm-project.git >> + $ mkdir -p llvm-project/llvm/build/install > > llvm-project/llvm/build/install is not used. Yes, just mkdir -p llvm-project/llvm/build is OK. > >> + $ cd llvm-project/llvm/build >> + $ cmake .. -G "Ninja" -DLLVM_TARGETS_TO_BUILD="BPF;X86" \ >> + -DLLVM_ENABLE_PROJECTS="clang" \ >> + -DBUILD_SHARED_LIBS=OFF \ > > -DBUILD_SHARED_LIBS=OFF is the default. It can be omitted. I search the related doc [1] [2], remove this option is OK for me. BUILD_SHARED_LIBS:BOOL Flag indicating if each LLVM component (e.g. Support) is built as a shared library (ON) or as a static library (OFF). Its default value is OFF. [1] https://www.llvm.org/docs/CMake.html [2] https://cmake.org/cmake/help/latest/variable/BUILD_SHARED_LIBS.html > >> + -DCMAKE_BUILD_TYPE=Release \ >> + -DLLVM_BUILD_RUNTIME=OFF > > -DLLVM_BUILD_RUNTIME=OFF can be omitted if none of > compiler-rt/libc++/libc++abi is built. I am not very sure about it because the default value of LLVM_BUILD_RUNTIME is ON? [3] option(LLVM_BUILD_RUNTIME "Build the LLVM runtime libraries." ON) [3] https://github.com/llvm/llvm-project/blob/main/llvm/CMakeLists.txt If anyone has any more suggestions, please let me know. I will send v3 after waiting for other feedback. By the way, Documentation/bpf/bpf_devel_QA.rst maybe need a separate patch to remove some cmake options? Thanks, Tiezhu > >> + $ ninja >> >> It is also possible to point make to the newly compiled 'llc' or >> 'clang' command via redefining LLC or CLANG on the make command line:: >> >> - make M=samples/bpf LLC=~/git/llvm/build/bin/llc >> CLANG=~/git/llvm/build/bin/clang >> + make M=samples/bpf LLC=~/git/llvm-project/llvm/build/bin/llc >> CLANG=~/git/llvm-project/llvm/build/bin/clang >> >> Cross compiling samples >> ----------------------- >> -- >> 2.1.0 >> >> -- >> You received this message because you are subscribed to the Google >> Groups "Clang Built Linux" group. >> To unsubscribe from this group and stop receiving emails from it, >> send an email to clang-built-linux+unsubscribe@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/clang-built-linux/1611042978-21473-1-git-send-email-yangtiezhu%40loongson.cn.