From patchwork Tue May 2 02:17:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 8823 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp308135vqo; Mon, 1 May 2023 19:20:03 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ4ShjknYAlV6tIyRuwXWBFxdcTkAZ2+e18pchaMPC/wGZaxWfHX8BOXd33uajzvjwUlmxRt X-Received: by 2002:a17:902:fa88:b0:1ab:bfb:4b6e with SMTP id lc8-20020a170902fa8800b001ab0bfb4b6emr498210plb.31.1682994002674; Mon, 01 May 2023 19:20:02 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1682994002; cv=none; d=google.com; s=arc-20160816; b=fTcn8flPxQ5eueJLf5tWLWnrAjGvXTVwkSkPGKqp0eoogIE8C/92qq9hyoumEMJTZ7 9IhhXUHx+k88RtodQmZ0X7J0wkedHsVTN+oFXBNnz9ELJ4H9Euv//pnbbIrOohoeeIEa qIYr+XU3aNmCY3+jF8wXG/MiXYvC7vkMMlvP7JjokLFgm+tHeEb4MHnA6HsUDaiZelXO hYb0uhvkAbFz6Aoildu6N30/NzMlAeh/3zPUiRzqtMZt+LEabitutNh0AazLnXqX34Dj 3Ezr/tCsoVYXffLAgz12vfvHM5ZmWfbrduaJOqlDQmMM0CObnPwqurMPyA+MdfKojME1 mGSA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:message-id:date:subject:cc:to:from:dkim-signature; bh=Wq9sd+Bw2TZVhwbYgN5DuuJWzRvqzQiKvJkrcl/Hduk=; b=Hv0lWRQgybKiUOWoZazo3gmL3eO2t89Obkleqr4RvgLeev2WX8KbvCP2dPa8mbPJp4 6URH4cMNfxfJqJPm331T8rbhOxi4IeLAkhXtsFyE6Gu86Y775afhpQ9BdhZ0AvL7zgam VibQK8iSValz1dwZi+TTAp4jl3GGNmfS4nE5RnSmxDB7/gpG634jDCne7kE0zjPT1Cu8 35YcbUeLG4GaUnGKenmOJxhyOUbRwe5JBGR2EJ/Umz5hSdVdHuGhFAiTPFODXG9Bh8zI b1ZrQEANSzAM56xguI7DVeHQ3K+tELlNVenkli8j5gTwqikdhbaYLZF4sSigBbBPqzM7 B3VQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=MT+WogSX; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id k11-20020a170902760b00b001a1bbc5bea5si24343990pll.537.2023.05.01.19.19.46; Mon, 01 May 2023 19:20:02 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=MT+WogSX; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233379AbjEBCR0 (ORCPT + 99 others); Mon, 1 May 2023 22:17:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42862 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230484AbjEBCRZ (ORCPT ); Mon, 1 May 2023 22:17:25 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D581230EA; Mon, 1 May 2023 19:17:23 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 5463D6208E; Tue, 2 May 2023 02:17:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1133EC4339B; Tue, 2 May 2023 02:17:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1682993842; bh=UtSIxSFYf3c1tokbMNWGDHpcjx1Gc1a0IuguMOoCqHk=; h=From:To:Cc:Subject:Date:From; b=MT+WogSX4WOA24K9yMV70qk6A9E9AAP+Sn4XJ8ogvjC1/V31oT6H1vps+k0VlM4PF M4LE4IY3X1Z/3pxM/SLw3zcA9Oo11jkwg38BbD7b4U6CJdRuEA/9AcKHiKaKlMYnVN 8X4d4ZbPmDXRU2GBzJe84kgY6DUBStHqzL5Lg8osC/j+nUCCZLt7fSBS1WpqzCMZ/u A30yLsUdrZwGSJluo7IkImufK3lYsP7G0Cl9ib3JsR4XPsKAwY/n9HfQCv+SVULUJ5 oBuuqH/Syf6Rbl2Msy+TXkTclrGYawqJpiWntqlryjjWmRxkGLtadOI8xf2QpgoCg0 9Pft2iPqYc/Pw== From: "Masami Hiramatsu (Google)" To: linux-trace-kernel@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Steven Rostedt , mhiramat@kernel.org, Florent Revest , Mark Rutland , Will Deacon , Mathieu Desnoyers , Martin KaFai Lau , bpf@vger.kernel.org Subject: [PATCH v9.1 00/11] tracing: Add fprobe/tracepoint events Date: Tue, 2 May 2023 11:17:19 +0900 Message-ID: <168299383880.3242086.7182498102007986127.stgit@mhiramat.roam.corp.google.com> X-Mailer: git-send-email 2.40.1.495.gc816e09b53d-goog User-Agent: StGit/0.19 MIME-Version: 1.0 X-Spam-Status: No, score=-7.3 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_HI, SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1764747119309832820?= X-GMAIL-MSGID: =?utf-8?q?1764747119309832820?= Hi, Here is the version 9.1 :) of improve fprobe and add a basic fprobe event support for ftrace (tracefs) and perf. Here is the previous version. https://lore.kernel.org/all/168295372484.3157983.731333785390494141.stgit@mhiramat.roam.corp.google.com/ This version fixes a build error with CONFIG_MODULES=n reported by kernel test bot ([4/11]). You can also get this series from: git://git.kernel.org/pub/scm/linux/kernel/git/mhiramat/linux.git topic/fprobe-event-ext With this fprobe events, we can continue to trace function entry/exit even if the CONFIG_KPROBES_ON_FTRACE is not available. Since CONFIG_KPROBES_ON_FTRACE requires the CONFIG_DYNAMIC_FTRACE_WITH_REGS, it is not available if the architecture only supports CONFIG_DYNAMIC_FTRACE_WITH_ARGS (e.g. arm64). And that means kprobe events can not probe function entry/exit effectively on such architecture. But this problem can be solved if the dynamic events supports fprobe events because fprobe events doesn't use kprobe but ftrace via fprobe. FPROBE EVENTS ============= Fprobe events allows user to add new events on the entry and exit of kernel functions (which can be ftraced). Unlike kprobe events, the fprobe events can only probe the function entry and exit, and it can only trace the function args, return value, and stacks. (no registers) For probing function body, users can continue to use the kprobe events. The tracepoint probe events (tprobe events) also allows user to add new events dynamically on the tracepoint. Most of the tracepoint already has trace-events, so this feature is useful if you only want to know a specific parameter, or trace the tracepoints which has no trace-events (e.g. sched_*_tp tracepoints only exposes the tracepoints.) The fprobe events syntax is; f[:[GRP/][EVENT]] FUNCTION [FETCHARGS] f[MAXACTIVE][:[GRP/][EVENT]] FUNCTION%return [FETCHARGS] And tracepoint probe events syntax is; t[:[GRP/][EVENT]] TRACEPOINT [FETCHARGS] This series includes BTF argument support for fprobe/tracepoint events, and kprobe events. This allows us to fetch a specific function parameter by name, and all parameters by '$$args'. Note that enabling this feature, you need to enable CONFIG_BPF_SYSCALL and confirm that your arch supports CONFIG_HAVE_FUNCTION_ARG_ACCESS_API. E.g. # echo 't kfree ptr' >> dynamic_events # echo 'f kfree object' >> dynamic_events # cat dynamic_events t:tracepoints/kfree kfree ptr=ptr f:fprobes/kfree__entry kfree object=object # echo 1 > events/fprobes/enable # echo 1 > events/tracepoints/enable # echo > trace # head -n 20 trace | tail # TASK-PID CPU# ||||| TIMESTAMP FUNCTION # | | | ||||| | | tail-84 [000] ..... 1324.561958: kfree__entry: (kfree+0x4/0x140) object=0xffff888006383c00 tail-84 [000] ...1. 1324.561961: kfree: (__probestub_kfree+0x4/0x10) ptr=0xffff888006383c00 tail-84 [000] ..... 1324.561988: kfree__entry: (kfree+0x4/0x140) object=0x0 tail-84 [000] ...1. 1324.561988: kfree: (__probestub_kfree+0x4/0x10) ptr=0x0 tail-84 [000] ..... 1324.561989: kfree__entry: (kfree+0x4/0x140) object=0xffff88800671e600 tail-84 [000] ...1. 1324.561989: kfree: (__probestub_kfree+0x4/0x10) ptr=0xffff88800671e600 tail-84 [000] ..... 1324.562368: kfree__entry: (kfree+0x4/0x140) object=0xffff8880065e0580 tail-84 [000] ...1. 1324.562369: kfree: (__probestub_kfree+0x4/0x10) ptr=0xffff8880065e0580 Thank you, --- Masami Hiramatsu (Google) (11): fprobe: Pass return address to the handlers tracing/probes: Add fprobe events for tracing function entry and exit. selftests/ftrace: Add fprobe related testcases tracing/probes: Add tracepoint support on fprobe_events tracing/probes: Move event parameter fetching code to common parser tracing/probes: Support function parameters if BTF is available tracing/probes: Add $$args meta argument for all function args tracing/probes: Add BTF retval type support selftests/ftrace: Add tracepoint probe test case selftests/ftrace: Add BTF arguments test cases Documentation: tracing/probes: Add fprobe event tracing document Documentation/trace/fprobetrace.rst | 187 +++ Documentation/trace/index.rst | 1 include/linux/fprobe.h | 11 include/linux/rethook.h | 2 include/linux/trace_events.h | 3 include/linux/tracepoint-defs.h | 1 include/linux/tracepoint.h | 5 kernel/kprobes.c | 1 kernel/trace/Kconfig | 26 kernel/trace/Makefile | 1 kernel/trace/bpf_trace.c | 6 kernel/trace/fprobe.c | 17 kernel/trace/rethook.c | 3 kernel/trace/trace.c | 13 kernel/trace/trace.h | 11 kernel/trace/trace_eprobe.c | 44 - kernel/trace/trace_fprobe.c | 1198 ++++++++++++++++++++ kernel/trace/trace_kprobe.c | 33 - kernel/trace/trace_probe.c | 504 +++++++- kernel/trace/trace_probe.h | 43 + kernel/trace/trace_uprobe.c | 8 lib/test_fprobe.c | 10 samples/fprobe/fprobe_example.c | 6 .../ftrace/test.d/dynevent/add_remove_btfarg.tc | 54 + .../ftrace/test.d/dynevent/add_remove_fprobe.tc | 26 .../ftrace/test.d/dynevent/add_remove_tprobe.tc | 27 .../ftrace/test.d/dynevent/fprobe_syntax_errors.tc | 99 ++ .../ftrace/test.d/dynevent/tprobe_syntax_errors.tc | 82 + .../ftrace/test.d/kprobe/kprobe_syntax_errors.tc | 13 29 files changed, 2295 insertions(+), 140 deletions(-) create mode 100644 Documentation/trace/fprobetrace.rst create mode 100644 kernel/trace/trace_fprobe.c create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/add_remove_btfarg.tc create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/add_remove_fprobe.tc create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/add_remove_tprobe.tc create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/tprobe_syntax_errors.tc -- Masami Hiramatsu (Google)