From patchwork Thu Aug 19 12:19:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Hanjun Guo X-Patchwork-Id: 500362 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 3CE2AC4338F for ; Thu, 19 Aug 2021 12:31:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1E3BF6113B for ; Thu, 19 Aug 2021 12:31:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239054AbhHSMbw (ORCPT ); Thu, 19 Aug 2021 08:31:52 -0400 Received: from szxga02-in.huawei.com ([45.249.212.188]:8886 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232676AbhHSMbv (ORCPT ); Thu, 19 Aug 2021 08:31:51 -0400 Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.57]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Gr3tP4jmYz8sWS; Thu, 19 Aug 2021 20:27:09 +0800 (CST) Received: from dggpemm500002.china.huawei.com (7.185.36.229) by dggemv704-chm.china.huawei.com (10.3.19.47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Thu, 19 Aug 2021 20:31:13 +0800 Received: from linux-ibm.site (10.175.102.37) by dggpemm500002.china.huawei.com (7.185.36.229) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Thu, 19 Aug 2021 20:31:13 +0800 From: Hanjun Guo To: Greg KH , Sasha Levin , CC: =?utf-8?q?Martin_Li=C5=A1ka?= , Jiri Slaby , Arnaldo Carvalho de Melo , Hanjun Guo Subject: [PATCH 5.10.y 5/6] perf annotate: Fix jump parsing for C++ code. Date: Thu, 19 Aug 2021 20:19:11 +0800 Message-ID: <1629375552-51897-6-git-send-email-guohanjun@huawei.com> X-Mailer: git-send-email 1.7.12.4 In-Reply-To: <1629375552-51897-1-git-send-email-guohanjun@huawei.com> References: <1629375552-51897-1-git-send-email-guohanjun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.102.37] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpemm500002.china.huawei.com (7.185.36.229) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Martin Liška commit 1f0e6edcd968ff19211245f7da6039e983aa51e5 upstream. Considering the following testcase: int foo(int a, int b) { for (unsigned i = 0; i < 1000000000; i++) a += b; return a; } int main() { foo (3, 4); return 0; } 'perf annotate' displays: 86.52 │40055e: → ja 40056c 13.37 │400560: mov -0x18(%rbp),%eax │400563: add %eax,-0x14(%rbp) │400566: addl $0x1,-0x4(%rbp) 0.11 │40056a: → jmp 400557 │40056c: mov -0x14(%rbp),%eax │40056f: pop %rbp and the 'ja 40056c' does not link to the location in the function. It's caused by fact that comma is wrongly parsed, it's part of function signature. With my patch I see: 86.52 │ ┌──ja 26 13.37 │ │ mov -0x18(%rbp),%eax │ │ add %eax,-0x14(%rbp) │ │ addl $0x1,-0x4(%rbp) 0.11 │ │↑ jmp 11 │26:└─→mov -0x14(%rbp),%eax and 'o' output prints: 86.52 │4005┌── ↓ ja 40056c 13.37 │4005│0: mov -0x18(%rbp),%eax │4005│3: add %eax,-0x14(%rbp) │4005│6: addl $0x1,-0x4(%rbp) 0.11 │4005│a: ↑ jmp 400557 │4005└─→ mov -0x14(%rbp),%eax On the contrary, compiling the very same file with gcc -x c, the parsing is fine because function arguments are not displayed: jmp 400543 Committer testing: Before: $ cat cpp_args_annotate.c int foo(int a, int b) { for (unsigned i = 0; i < 1000000000; i++) a += b; return a; } int main() { foo (3, 4); return 0; } $ gcc --version |& head -1 gcc (GCC) 10.2.1 20201125 (Red Hat 10.2.1-9) $ gcc -g cpp_args_annotate.c -o cpp_args_annotate $ perf record ./cpp_args_annotate [ perf record: Woken up 2 times to write data ] [ perf record: Captured and wrote 0.275 MB perf.data (7188 samples) ] $ perf annotate --stdio2 foo Samples: 7K of event 'cycles:u', 4000 Hz, Event count (approx.): 7468429289, [percent: local period] foo() /home/acme/c/cpp_args_annotate Percent 0000000000401106 : foo(): int foo(int a, int b) { push %rbp mov %rsp,%rbp mov %edi,-0x14(%rbp) mov %esi,-0x18(%rbp) for (unsigned i = 0; i < 1000000000; i++) movl $0x0,-0x4(%rbp) ↓ jmp 1d a += b; 13.45 13: mov -0x18(%rbp),%eax add %eax,-0x14(%rbp) for (unsigned i = 0; i < 1000000000; i++) addl $0x1,-0x4(%rbp) 0.09 1d: cmpl $0x3b9ac9ff,-0x4(%rbp) 86.46 ↑ jbe 13 return a; mov -0x14(%rbp),%eax } pop %rbp ← retq $ I.e. works for C, now lets switch to C++: $ g++ -g cpp_args_annotate.c -o cpp_args_annotate $ perf record ./cpp_args_annotate [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.268 MB perf.data (6976 samples) ] $ perf annotate --stdio2 foo Samples: 6K of event 'cycles:u', 4000 Hz, Event count (approx.): 7380681761, [percent: local period] foo() /home/acme/c/cpp_args_annotate Percent 0000000000401106 : foo(int, int): int foo(int a, int b) { push %rbp mov %rsp,%rbp mov %edi,-0x14(%rbp) mov %esi,-0x18(%rbp) for (unsigned i = 0; i < 1000000000; i++) movl $0x0,-0x4(%rbp) cmpl $0x3b9ac9ff,-0x4(%rbp) 86.53 → ja 40112c a += b; 13.32 mov -0x18(%rbp),%eax 0.00 add %eax,-0x14(%rbp) for (unsigned i = 0; i < 1000000000; i++) addl $0x1,-0x4(%rbp) 0.15 → jmp 401117 return a; mov -0x14(%rbp),%eax } pop %rbp ← retq $ Reproduced. Now with this patch: Reusing the C++ built binary, as we can see here: $ readelf -wi cpp_args_annotate | grep producer DW_AT_producer : (indirect string, offset: 0x2e): GNU C++14 10.2.1 20201125 (Red Hat 10.2.1-9) -mtune=generic -march=x86-64 -g $ And furthermore: $ file cpp_args_annotate cpp_args_annotate: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=4fe3cab260204765605ec630d0dc7a7e93c361a9, for GNU/Linux 3.2.0, with debug_info, not stripped $ perf buildid-list -i cpp_args_annotate 4fe3cab260204765605ec630d0dc7a7e93c361a9 $ perf buildid-list | grep cpp_args_annotate 4fe3cab260204765605ec630d0dc7a7e93c361a9 /home/acme/c/cpp_args_annotate $ It now works: $ perf annotate --stdio2 foo Samples: 6K of event 'cycles:u', 4000 Hz, Event count (approx.): 7380681761, [percent: local period] foo() /home/acme/c/cpp_args_annotate Percent 0000000000401106 : foo(int, int): int foo(int a, int b) { push %rbp mov %rsp,%rbp mov %edi,-0x14(%rbp) mov %esi,-0x18(%rbp) for (unsigned i = 0; i < 1000000000; i++) movl $0x0,-0x4(%rbp) 11: cmpl $0x3b9ac9ff,-0x4(%rbp) 86.53 ↓ ja 26 a += b; 13.32 mov -0x18(%rbp),%eax 0.00 add %eax,-0x14(%rbp) for (unsigned i = 0; i < 1000000000; i++) addl $0x1,-0x4(%rbp) 0.15 ↑ jmp 11 return a; 26: mov -0x14(%rbp),%eax } pop %rbp ← retq $ Signed-off-by: Martin Liška Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Slaby Link: http://lore.kernel.org/lkml/13e1a405-edf9-e4c2-4327-a9b454353730@suse.cz Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Hanjun Guo --- tools/perf/util/annotate.c | 8 ++++++++ tools/perf/util/annotate.h | 1 + 2 files changed, 9 insertions(+) diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c index 6c8575e..3081894 100644 --- a/tools/perf/util/annotate.c +++ b/tools/perf/util/annotate.c @@ -317,12 +317,18 @@ bool ins__is_call(const struct ins *ins) /* * Prevents from matching commas in the comment section, e.g.: * ffff200008446e70: b.cs ffff2000084470f4 // b.hs, b.nlast + * + * and skip comma as part of function arguments, e.g.: + * 1d8b4ac */ static inline const char *validate_comma(const char *c, struct ins_operands *ops) { if (ops->raw_comment && c > ops->raw_comment) return NULL; + if (ops->raw_func_start && c > ops->raw_func_start) + return NULL; + return c; } @@ -337,6 +343,8 @@ static int jump__parse(struct arch *arch, struct ins_operands *ops, struct map_s u64 start, end; ops->raw_comment = strchr(ops->raw, arch->objdump.comment_char); + ops->raw_func_start = strchr(ops->raw, '<'); + c = validate_comma(c, ops); /* diff --git a/tools/perf/util/annotate.h b/tools/perf/util/annotate.h index 0a0cd4f..096cdaf 100644 --- a/tools/perf/util/annotate.h +++ b/tools/perf/util/annotate.h @@ -32,6 +32,7 @@ struct ins { struct ins_operands { char *raw; char *raw_comment; + char *raw_func_start; struct { char *raw; char *name;