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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=no 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 611DBC2BA83 for ; Wed, 12 Feb 2020 12:50:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6204320714 for ; Wed, 12 Feb 2020 12:50:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727856AbgBLMus (ORCPT ); Wed, 12 Feb 2020 07:50:48 -0500 Received: from mga06.intel.com ([134.134.136.31]:63674 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725887AbgBLMus (ORCPT ); Wed, 12 Feb 2020 07:50:48 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 12 Feb 2020 04:50:47 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,428,1574150400"; d="scan'208";a="237702401" Received: from ahunter-desktop.fi.intel.com ([10.237.72.167]) by orsmga006.jf.intel.com with ESMTP; 12 Feb 2020 04:50:43 -0800 From: Adrian Hunter To: Peter Zijlstra Cc: Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , x86@kernel.org, Mark Rutland , Alexander Shishkin , Mathieu Poirier , Leo Yan , Arnaldo Carvalho de Melo , Jiri Olsa , linux-kernel@vger.kernel.org Subject: [PATCH V2 00/13] perf/x86: Add perf text poke events Date: Wed, 12 Feb 2020 14:49:36 +0200 Message-Id: <20200212124949.3589-1-adrian.hunter@intel.com> X-Mailer: git-send-email 2.17.1 Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Here are patches to add a text poke event to record changes to kernel text (i.e. self-modifying code) in order to support tracers like Intel PT decoding through jump labels, kprobes and ftrace trampolines. The first 8 patches make the kernel changes and the subsequent patches are tools changes. The next 4 patches add support for updating perf tools' data cache with the changed bytes. The last patch is an Intel PT specific tools change. Changes in V2: perf: Add perf text poke event Separate out x86 changes The text poke event now has old len and new len Revised commit message perf/x86: Add support for perf text poke event for text_poke_bp_batch() callers New patch containing x86 changes from original first patch kprobes: Add symbols for kprobe insn pages kprobes: Add perf ksymbol events for kprobe insn pages perf/x86: Add perf text poke events for kprobes ftrace: Add symbols for ftrace trampolines ftrace: Add perf ksymbol events for ftrace trampolines ftrace: Add perf text poke events for ftrace trampolines perf kcore_copy: Fix module map when there are no modules loaded perf evlist: Disable 'immediate' events last New patches perf tools: Add support for PERF_RECORD_TEXT_POKE The text poke event now has old len and new len Also select ksymbol events with text poke events perf tools: Add support for PERF_RECORD_KSYMBOL_TYPE_OOL New patch perf intel-pt: Add support for text poke events The text poke event now has old len and new len Allow for the address not having a map yet Changes since RFC: Dropped 'flags' from the new event. The consensus seemed to be that text pokes should employ a scheme similar to x86's INT3 method instead. dropped tools patches already applied. Example: For jump labels, the kernel needs CONFIG_JUMP_LABEL=y and also an easy to flip jump label is in sysctl_schedstats() which needs CONFIG_SCHEDSTATS=y CONFIG_PROC_SYSCTL=y CONFIG_SCHED_DEBUG=y Also note the 'sudo perf record' is put into the background which, as written, needs sudo credential caching (otherwise the background task will stop awaiting the sudo password), hence the 'sudo echo' to start. Before: $ sudo echo $ sudo perf record -o perf.data.before --kcore -a -e intel_pt//k -m,64M & [1] 1640 $ cat /proc/sys/kernel/sched_schedstats 0 $ sudo bash -c 'echo 1 > /proc/sys/kernel/sched_schedstats' $ cat /proc/sys/kernel/sched_schedstats 1 $ sudo bash -c 'echo 0 > /proc/sys/kernel/sched_schedstats' $ cat /proc/sys/kernel/sched_schedstats 0 $ sudo kill 1640 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 16.635 MB perf.data.before ] $ perf script -i perf.data.before --itrace=e >/dev/null Warning: 1946 instruction trace errors After: $ sudo echo $ sudo perf record -o perf.data.after --kcore -a -e intel_pt//k -m,64M & [1] 1882 $ cat /proc/sys/kernel/sched_schedstats 0 $ sudo bash -c 'echo 1 > /proc/sys/kernel/sched_schedstats' $ cat /proc/sys/kernel/sched_schedstats 1 $ sudo bash -c 'echo 0 > /proc/sys/kernel/sched_schedstats' $ cat /proc/sys/kernel/sched_schedstats 0 $ sudo kill 1882 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 10.893 MB perf.data.after ] $ perf script -i perf.data.after --itrace=e $ Adrian Hunter (13): perf: Add perf text poke event perf/x86: Add support for perf text poke event for text_poke_bp_batch() callers kprobes: Add symbols for kprobe insn pages kprobes: Add perf ksymbol events for kprobe insn pages perf/x86: Add perf text poke events for kprobes ftrace: Add symbols for ftrace trampolines ftrace: Add perf ksymbol events for ftrace trampolines ftrace: Add perf text poke events for ftrace trampolines perf kcore_copy: Fix module map when there are no modules loaded perf evlist: Disable 'immediate' events last perf tools: Add support for PERF_RECORD_TEXT_POKE perf tools: Add support for PERF_RECORD_KSYMBOL_TYPE_OOL perf intel-pt: Add support for text poke events arch/x86/include/asm/kprobes.h | 4 ++ arch/x86/include/asm/text-patching.h | 2 + arch/x86/kernel/alternative.c | 70 +++++++++++++++++++----- arch/x86/kernel/ftrace.c | 37 ++++++++----- arch/x86/kernel/kprobes/core.c | 7 +++ arch/x86/kernel/kprobes/opt.c | 18 ++++++- include/linux/ftrace.h | 15 ++++-- include/linux/kprobes.h | 28 ++++++++++ include/linux/perf_event.h | 8 +++ include/uapi/linux/perf_event.h | 26 ++++++++- kernel/events/core.c | 90 ++++++++++++++++++++++++++++++- kernel/kallsyms.c | 32 +++++++++-- kernel/kprobes.c | 57 ++++++++++++++++++++ kernel/trace/ftrace.c | 52 +++++++++++++++++- tools/include/uapi/linux/perf_event.h | 26 ++++++++- tools/lib/perf/include/perf/event.h | 9 ++++ tools/perf/arch/x86/util/intel-pt.c | 4 ++ tools/perf/builtin-record.c | 45 ++++++++++++++++ tools/perf/util/dso.c | 3 ++ tools/perf/util/dso.h | 1 + tools/perf/util/event.c | 40 ++++++++++++++ tools/perf/util/event.h | 5 ++ tools/perf/util/evlist.c | 31 +++++++---- tools/perf/util/evlist.h | 1 + tools/perf/util/evsel.c | 7 ++- tools/perf/util/intel-pt.c | 75 ++++++++++++++++++++++++++ tools/perf/util/machine.c | 49 +++++++++++++++++ tools/perf/util/machine.h | 3 ++ tools/perf/util/map.c | 5 ++ tools/perf/util/map.h | 3 +- tools/perf/util/perf_event_attr_fprintf.c | 1 + tools/perf/util/record.c | 10 ++++ tools/perf/util/record.h | 1 + tools/perf/util/session.c | 23 ++++++++ tools/perf/util/symbol-elf.c | 7 +++ tools/perf/util/symbol.c | 1 + tools/perf/util/tool.h | 3 +- 37 files changed, 748 insertions(+), 51 deletions(-) Regards Adrian