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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,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 AB11CC1B08C for ; Thu, 15 Jul 2021 06:47:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8DADB600CD for ; Thu, 15 Jul 2021 06:47:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231465AbhGOGub (ORCPT ); Thu, 15 Jul 2021 02:50:31 -0400 Received: from szxga01-in.huawei.com ([45.249.212.187]:15017 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229526AbhGOGua (ORCPT ); Thu, 15 Jul 2021 02:50:30 -0400 Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.54]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4GQPww6r2rzbcqn; Thu, 15 Jul 2021 14:44:16 +0800 (CST) Received: from dggpemm000003.china.huawei.com (7.185.36.128) 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, 15 Jul 2021 14:47:34 +0800 Received: from [10.67.102.248] (10.67.102.248) by dggpemm000003.china.huawei.com (7.185.36.128) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Thu, 15 Jul 2021 14:47:34 +0800 Subject: Re: [PATCH] perf probe: Fix add event failed when 32-bit perf running in 64-bit kernel To: Masami Hiramatsu CC: , , , , , , , , , , , , , , , References: <20210714065432.188061-1-yangjihong1@huawei.com> <20210714173553.944cef13897dfe1bea7b8d78@kernel.org> <9cb859df-f2ef-732b-756e-c8d2acefe85c@huawei.com> <20210715135821.c58ca2ff97b0c1db449db0b4@kernel.org> From: Yang Jihong Message-ID: <03aadc60-d43e-0b4b-822e-39818d9203ef@huawei.com> Date: Thu, 15 Jul 2021 14:47:34 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: <20210715135821.c58ca2ff97b0c1db449db0b4@kernel.org> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-Originating-IP: [10.67.102.248] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm000003.china.huawei.com (7.185.36.128) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Hiramatsu, On 2021/7/15 12:58, Masami Hiramatsu wrote: > On Thu, 15 Jul 2021 09:20:01 +0800 > Yang Jihong wrote: > >> Hello Hiramatsu, >> >> On 2021/7/14 16:35, Masami Hiramatsu wrote: >>> Hi Yang, >>> >>> On Wed, 14 Jul 2021 14:54:32 +0800 >>> Yang Jihong wrote: >>> >>>> The "address" member of "struct probe_trace_point" uses long data type. >>>> If kernel is 64-bit and perf program is 32-bit, size of "address" variable is >>>> 32 bits. As a result, upper 32 bits of address read from kernel are truncated, >>>> An error occurs during address comparison in kprobe_warn_out_range function. >>> >>> Good catch! >>> I didn't imagine that such a use case. But that is important because perf >>> probe can be used for cross-arch probe definition too. >>> >>>> >>>> Before: >>>> >>>> # perf probe -a schedule >>>> schedule is out of .text, skip it. >>>> Error: Failed to add events. >>>> >>>> Solution: >>>> Change data type of "address" variable to u64 and change corresponding >>>> address printing and value assignment. >>> >>> OK, as far as I can see, the other parts of the perf also uses u64 for >>> "address" storing variables. (e.g. symbols, maps etc.) >>> >>>> >>>> After: >>>> >>>> # perf.new.new probe -a schedule >>>> Added new event: >>>> probe:schedule (on schedule) >>>> >>>> You can now use it in all perf tools, such as: >>>> >>>> perf record -e probe:schedule -aR sleep 1 >>>> >>>> # perf probe -l >>>> probe:schedule (on schedule) >>> >>> I think you missed one thing here. >>> Usually, this shows the filename and line number of schedule(). >> Yes, I tried the following diff and now it can show the filename (as is >> function entry, relative line number is 0), thank you very much :) >> >> The test result in my environment is as follows: >> >> # perf probe -a schedule >> Added new event: >> probe:schedule (on schedule) >> >> You can now use it in all perf tools, such as: >> >> perf record -e probe:schedule -aR sleep 1 >> >> # perf probe -l schedule -k vmlinux.debug >> probe:schedule (on schedule@kernel/sched/core.c) >> > > OK, good! > >> >> Can I put the following diff together and submit a v2 patch? > > Yes, please include this fix in your patch, because it is what your patch > has to do :) > OK，I have submitted the v2 patch: https://lore.kernel.org/patchwork/patch/1460154/ Thanks very much for your patient review.:) Jihong > Thank you! > >>> >>> Could you try below diff? >>> >>> diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c >>> index 7d2ba8419b0c..609ca1671501 100644 >>> --- a/tools/perf/util/dwarf-aux.c >>> +++ b/tools/perf/util/dwarf-aux.c >>> @@ -113,14 +113,14 @@ static Dwarf_Line *cu_getsrc_die(Dwarf_Die *cu_die, Dwarf_Addr addr) >>> * >>> * Find a line number and file name for @addr in @cu_die. >>> */ >>> -int cu_find_lineinfo(Dwarf_Die *cu_die, unsigned long addr, >>> - const char **fname, int *lineno) >>> +int cu_find_lineinfo(Dwarf_Die *cu_die, Dwarf_Addr addr, >>> + const char **fname, int *lineno) >>> { >>> Dwarf_Line *line; >>> Dwarf_Die die_mem; >>> Dwarf_Addr faddr; >>> >>> - if (die_find_realfunc(cu_die, (Dwarf_Addr)addr, &die_mem) >>> + if (die_find_realfunc(cu_die, addr, &die_mem) >>> && die_entrypc(&die_mem, &faddr) == 0 && >>> faddr == addr) { >>> *fname = dwarf_decl_file(&die_mem); >>> @@ -128,7 +128,7 @@ int cu_find_lineinfo(Dwarf_Die *cu_die, unsigned long addr, >>> goto out; >>> } >>> >>> - line = cu_getsrc_die(cu_die, (Dwarf_Addr)addr); >>> + line = cu_getsrc_die(cu_die, addr); >>> if (line && dwarf_lineno(line, lineno) == 0) { >>> *fname = dwarf_linesrc(line, NULL, NULL); >>> if (!*fname) >>> diff --git a/tools/perf/util/dwarf-aux.h b/tools/perf/util/dwarf-aux.h >>> index cb99646843a9..7ee0fa19b5c4 100644 >>> --- a/tools/perf/util/dwarf-aux.h >>> +++ b/tools/perf/util/dwarf-aux.h >>> @@ -19,7 +19,7 @@ const char *cu_find_realpath(Dwarf_Die *cu_die, const char *fname); >>> const char *cu_get_comp_dir(Dwarf_Die *cu_die); >>> >>> /* Get a line number and file name for given address */ >>> -int cu_find_lineinfo(Dwarf_Die *cudie, unsigned long addr, >>> +int cu_find_lineinfo(Dwarf_Die *cudie, Dwarf_Addr addr, >>> const char **fname, int *lineno); >>> >>> /* Walk on functions at given address */ >>> diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c >>> index 8ba01bbdf05c..50d861a80f57 100644 >>> --- a/tools/perf/util/probe-finder.c >>> +++ b/tools/perf/util/probe-finder.c >>> @@ -1727,7 +1727,7 @@ int debuginfo__find_probe_point(struct debuginfo *dbg, u64 addr, >>> } >>> >>> /* Find a corresponding line (filename and lineno) */ >>> - cu_find_lineinfo(&cudie, addr, &fname, &lineno); >>> + cu_find_lineinfo(&cudie, (Dwarf_Addr)addr, &fname, &lineno); >>> /* Don't care whether it failed or not */ >>> >>> /* Find a corresponding function (name, baseline and baseaddr) */ >>> @@ -1828,8 +1828,7 @@ static int line_range_add_line(const char *src, unsigned int lineno, >>> } >>> >>> static int line_range_walk_cb(const char *fname, int lineno, >>> - Dwarf_Addr addr __maybe_unused, >>> - void *data) >>> + Dwarf_Addr addr, void *data) >>> { >>> struct line_finder *lf = data; >>> const char *__fname; >>> >>> > >