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[209.132.180.67]) by mx.google.com with ESMTP id rr8si12766751pab.223.2016.02.26.01.35.35; Fri, 26 Feb 2016 01:35:35 -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 S1753649AbcBZJfb (ORCPT + 30 others); Fri, 26 Feb 2016 04:35:31 -0500 Received: from szxga03-in.huawei.com ([119.145.14.66]:10322 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753588AbcBZJf1 (ORCPT ); Fri, 26 Feb 2016 04:35:27 -0500 Received: from 172.24.1.51 (EHLO szxeml422-hub.china.huawei.com) ([172.24.1.51]) by szxrg03-dlp.huawei.com (MOS 4.4.3-GA FastPath queued) with ESMTP id BWR34388; Fri, 26 Feb 2016 17:32:48 +0800 (CST) Received: from linux-4hy3.site (10.107.193.248) by szxeml422-hub.china.huawei.com (10.82.67.152) with Microsoft SMTP Server id 14.3.235.1; Fri, 26 Feb 2016 17:32:38 +0800 From: Wang Nan To: Alexei Starovoitov , Arnaldo Carvalho de Melo , Arnaldo Carvalho de Melo CC: Jiri Olsa , Li Zefan , "Peter Zijlstra" , , Wang Nan , , Adrian Hunter , Cody P Schafer , He Kuang , Kirill Smelkov , Masami Hiramatsu , Namhyung Kim Subject: [PATCH 01/46] perf tools: Record text offset in dso to calculate objdump address Date: Fri, 26 Feb 2016 09:31:49 +0000 Message-ID: <1456479154-136027-2-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1456479154-136027-1-git-send-email-wangnan0@huawei.com> References: <1456479154-136027-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.107.193.248] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A090205.56D01BD7.009D, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2013-05-26 15:14:31, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 54b5a0f9d113c89e74ea29b3d8dfc199 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In this patch, the offset of '.text' section is stored into dso and used here to re-calculate address to objdump. In most of the cases, executable code is in '.text' section, so the adjustment made to a symbol in dso__load_sym (using sym.st_value -= shdr.sh_addr - shdr.sh_offset) should equal to 'sym.st_value -= dso->text_offset'. Therefore, adding text_offset back get objdump address from symbol address (rip). However, it is not true for kernel and kernel module since there could be multiple executable sections with different offset. Exclude kernel for this reason. After this patch, even dso->adjust_symbols is set to true for shared objects, map__rip_2objdump() and map__objdump_2mem() would return correct result, so perf behavior of annotate won't be changed. Signed-off-by: Wang Nan Cc: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Cody P Schafer Cc: He Kuang Cc: Jiri Olsa Cc: Kirill Smelkov Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Li Zefan Cc: pi3orama@163.com --- tools/perf/util/dso.h | 1 + tools/perf/util/map.c | 14 ++++++++++++++ tools/perf/util/symbol-elf.c | 12 ++++++------ 3 files changed, 21 insertions(+), 6 deletions(-) -- 1.8.3.4 diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h index 45ec4d0..ef3dbc9 100644 --- a/tools/perf/util/dso.h +++ b/tools/perf/util/dso.h @@ -162,6 +162,7 @@ struct dso { u8 loaded; u8 rel; u8 build_id[BUILD_ID_SIZE]; + u64 text_offset; const char *short_name; const char *long_name; u16 long_name_len; diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c index 171b6d1..02c3186 100644 --- a/tools/perf/util/map.c +++ b/tools/perf/util/map.c @@ -431,6 +431,13 @@ u64 map__rip_2objdump(struct map *map, u64 rip) if (map->dso->rel) return rip - map->pgoff; + /* + * kernel modules also have DSO_TYPE_USER in dso->kernel, + * but all kernel modules are ET_REL, so won't get here. + */ + if (map->dso->kernel == DSO_TYPE_USER) + return rip + map->dso->text_offset; + return map->unmap_ip(map, rip) - map->reloc; } @@ -454,6 +461,13 @@ u64 map__objdump_2mem(struct map *map, u64 ip) if (map->dso->rel) return map->unmap_ip(map, ip + map->pgoff); + /* + * kernel modules also have DSO_TYPE_USER in dso->kernel, + * but all kernel modules are ET_REL, so won't get here. + */ + if (map->dso->kernel == DSO_TYPE_USER) + return map->unmap_ip(map, ip - map->dso->text_offset); + return ip + map->reloc; } diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index b1dd68f..bc229a7 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -793,6 +793,7 @@ int dso__load_sym(struct dso *dso, struct map *map, uint32_t idx; GElf_Ehdr ehdr; GElf_Shdr shdr; + GElf_Shdr tshdr; Elf_Data *syms, *opddata = NULL; GElf_Sym sym; Elf_Scn *sec, *sec_strndx; @@ -832,6 +833,9 @@ int dso__load_sym(struct dso *dso, struct map *map, sec = syms_ss->symtab; shdr = syms_ss->symshdr; + if (elf_section_by_name(elf, &ehdr, &tshdr, ".text", NULL)) + dso->text_offset = tshdr.sh_addr - tshdr.sh_offset; + if (runtime_ss->opdsec) opddata = elf_rawdata(runtime_ss->opdsec, NULL); @@ -880,12 +884,8 @@ int dso__load_sym(struct dso *dso, struct map *map, * Handle any relocation of vdso necessary because older kernels * attempted to prelink vdso to its virtual address. */ - if (dso__is_vdso(dso)) { - GElf_Shdr tshdr; - - if (elf_section_by_name(elf, &ehdr, &tshdr, ".text", NULL)) - map->reloc = map->start - tshdr.sh_addr + tshdr.sh_offset; - } + if (dso__is_vdso(dso)) + map->reloc = map->start - dso->text_offset; dso->adjust_symbols = runtime_ss->adjust_symbols || ref_reloc(kmap); /*