From patchwork Tue Aug 18 21:59:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 262333 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=-12.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 0933EC433DF for ; Tue, 18 Aug 2020 21:59:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D536720709 for ; Tue, 18 Aug 2020 21:59:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="Qeu7rkDX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726948AbgHRV7a (ORCPT ); Tue, 18 Aug 2020 17:59:30 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:16996 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726845AbgHRV72 (ORCPT ); Tue, 18 Aug 2020 17:59:28 -0400 Received: from pps.filterd (m0044012.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 07ILueh1029214 for ; Tue, 18 Aug 2020 14:59:27 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=AFMfneqWrl/uKXX51lGxf4hgFXQ8Nam4MH3QQNOIKz0=; b=Qeu7rkDXoOM79Bl1sc4U/M8uK+PXWlK9dLWJl+7vfwCEKpP2eHIX1HIobxKR6MnGj+Kt bv1vXlSo/UD4SxpB5k8+LvXmwIyh+m42GDp3RzQSCI+iR5slorwcQCN8pNIkozf5lZ1u 6D3sex5916hfKQ+JJEfk2lw7boLT7vp6fso= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com with ESMTP id 3304p3d88n-5 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Tue, 18 Aug 2020 14:59:27 -0700 Received: from intmgw005.03.ash8.facebook.com (2620:10d:c085:208::f) by mail.thefacebook.com (2620:10d:c085:21d::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Tue, 18 Aug 2020 14:59:25 -0700 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id 710A12EC5EB3; Tue, 18 Aug 2020 14:59:20 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Andrii Nakryiko Smtp-Origin-Hostname: devbig012.ftw2.facebook.com To: , , , CC: , , Andrii Nakryiko Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH bpf-next 4/4] tools: remove feature-libelf-mmap feature detection Date: Tue, 18 Aug 2020 14:59:08 -0700 Message-ID: <20200818215908.2746786-5-andriin@fb.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200818215908.2746786-1-andriin@fb.com> References: <20200818215908.2746786-1-andriin@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235, 18.0.687 definitions=2020-08-18_16:2020-08-18,2020-08-18 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 mlxlogscore=999 spamscore=0 mlxscore=0 clxscore=1015 suspectscore=8 adultscore=0 bulkscore=0 impostorscore=0 phishscore=0 priorityscore=1501 malwarescore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2008180157 X-FB-Internal: deliver Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org It's trivial to handle missing ELF_C_MMAP_READ support in libelf the way that objtool has solved it in ("774bec3fddcc objtool: Add fallback from ELF_C_READ_MMAP to ELF_C_READ"). So instead of having an entire feature detector for that, just do what objtool does for perf and libbpf. And keep their Makefiles a bit simpler. Signed-off-by: Andrii Nakryiko --- tools/build/Makefile.feature | 1 - tools/build/feature/Makefile | 4 ---- tools/build/feature/test-all.c | 4 ---- tools/build/feature/test-libelf-mmap.c | 9 --------- tools/lib/bpf/Makefile | 6 +----- tools/lib/bpf/libbpf.c | 14 ++++++-------- tools/perf/Makefile.config | 4 ---- tools/perf/util/symbol.h | 2 +- 8 files changed, 8 insertions(+), 36 deletions(-) delete mode 100644 tools/build/feature/test-libelf-mmap.c diff --git a/tools/build/Makefile.feature b/tools/build/Makefile.feature index c1daf4d57518..38415d251075 100644 --- a/tools/build/Makefile.feature +++ b/tools/build/Makefile.feature @@ -46,7 +46,6 @@ FEATURE_TESTS_BASIC := \ libelf-getphdrnum \ libelf-gelf_getnote \ libelf-getshdrstrndx \ - libelf-mmap \ libnuma \ numa_num_possible_cpus \ libperl \ diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile index d220fe952747..b2a2347c67ed 100644 --- a/tools/build/feature/Makefile +++ b/tools/build/feature/Makefile @@ -25,7 +25,6 @@ FILES= \ test-libelf-getphdrnum.bin \ test-libelf-gelf_getnote.bin \ test-libelf-getshdrstrndx.bin \ - test-libelf-mmap.bin \ test-libdebuginfod.bin \ test-libnuma.bin \ test-numa_num_possible_cpus.bin \ @@ -146,9 +145,6 @@ $(OUTPUT)test-dwarf.bin: $(OUTPUT)test-dwarf_getlocations.bin: $(BUILD) $(DWARFLIBS) -$(OUTPUT)test-libelf-mmap.bin: - $(BUILD) -lelf - $(OUTPUT)test-libelf-getphdrnum.bin: $(BUILD) -lelf diff --git a/tools/build/feature/test-all.c b/tools/build/feature/test-all.c index 5479e543b194..5284e6e9c756 100644 --- a/tools/build/feature/test-all.c +++ b/tools/build/feature/test-all.c @@ -30,10 +30,6 @@ # include "test-libelf.c" #undef main -#define main main_test_libelf_mmap -# include "test-libelf-mmap.c" -#undef main - #define main main_test_get_current_dir_name # include "test-get_current_dir_name.c" #undef main diff --git a/tools/build/feature/test-libelf-mmap.c b/tools/build/feature/test-libelf-mmap.c deleted file mode 100644 index 2c3ef81affe2..000000000000 --- a/tools/build/feature/test-libelf-mmap.c +++ /dev/null @@ -1,9 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -#include - -int main(void) -{ - Elf *elf = elf_begin(0, ELF_C_READ_MMAP, 0); - - return (long)elf; -} diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile index 99796cfc1b9b..eb193bdf43f9 100644 --- a/tools/lib/bpf/Makefile +++ b/tools/lib/bpf/Makefile @@ -56,7 +56,7 @@ ifndef VERBOSE endif FEATURE_USER = .libbpf -FEATURE_TESTS = libelf libelf-mmap zlib bpf +FEATURE_TESTS = libelf zlib bpf FEATURE_DISPLAY = libelf zlib bpf INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(ARCH)/include/uapi -I$(srctree)/tools/include/uapi @@ -98,10 +98,6 @@ else CFLAGS := -g -Wall endif -ifeq ($(feature-libelf-mmap), 1) - override CFLAGS += -DHAVE_LIBELF_MMAP_SUPPORT -endif - # Append required CFLAGS override CFLAGS += $(EXTRA_WARNINGS) override CFLAGS += -Werror -Wall diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index f3f4963d6ba4..78d883c5a8f7 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -150,12 +150,6 @@ static void pr_perm_msg(int err) ___err; }) #endif -#ifdef HAVE_LIBELF_MMAP_SUPPORT -# define LIBBPF_ELF_C_READ_MMAP ELF_C_READ_MMAP -#else -# define LIBBPF_ELF_C_READ_MMAP ELF_C_READ -#endif - static inline __u64 ptr_to_u64(const void *ptr) { return (__u64) (unsigned long) ptr; @@ -1062,6 +1056,11 @@ static void bpf_object__elf_finish(struct bpf_object *obj) obj->efile.obj_buf_sz = 0; } +/* if libelf is old and doesn't support mmap(), fall back to read() */ +#ifndef ELF_C_READ_MMAP +#define ELF_C_READ_MMAP ELF_C_READ +#endif + static int bpf_object__elf_init(struct bpf_object *obj) { int err = 0; @@ -1090,8 +1089,7 @@ static int bpf_object__elf_init(struct bpf_object *obj) return err; } - obj->efile.elf = elf_begin(obj->efile.fd, - LIBBPF_ELF_C_READ_MMAP, NULL); + obj->efile.elf = elf_begin(obj->efile.fd, ELF_C_READ_MMAP, NULL); } if (!obj->efile.elf) { diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config index 190be4fa5c21..81bb099f6f06 100644 --- a/tools/perf/Makefile.config +++ b/tools/perf/Makefile.config @@ -483,10 +483,6 @@ ifndef NO_LIBELF EXTLIBS += -lelf $(call detected,CONFIG_LIBELF) - ifeq ($(feature-libelf-mmap), 1) - CFLAGS += -DHAVE_LIBELF_MMAP_SUPPORT - endif - ifeq ($(feature-libelf-getphdrnum), 1) CFLAGS += -DHAVE_ELF_GETPHDRNUM_SUPPORT endif diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h index ff4f4c47e148..03e264a27cd3 100644 --- a/tools/perf/util/symbol.h +++ b/tools/perf/util/symbol.h @@ -28,7 +28,7 @@ struct option; * libelf 0.8.x and earlier do not support ELF_C_READ_MMAP; * for newer versions we can use mmap to reduce memory usage: */ -#ifdef HAVE_LIBELF_MMAP_SUPPORT +#ifdef ELF_C_READ_MMAP # define PERF_ELF_C_READ_MMAP ELF_C_READ_MMAP #else # define PERF_ELF_C_READ_MMAP ELF_C_READ