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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 BB27EC0650E for ; Thu, 4 Jul 2019 06:40:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 840C821882 for ; Thu, 4 Jul 2019 06:40:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562222404; bh=EJ5pWcgs9Xg/Wu0hHSUeJaZ/LScLq5frs0oVc8rOuEw=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=Vq/LVQgvtCFRXuF9baf/azmH5nnQgLyDzAWfNgCXr4iHIuJYD3Zp0WJEK8GdR/e7Z LE2oIqNfbZNZekHi9abJeV0QBVtx+d1n3LtcNE7QdP0AO4YCejrOkGmnBJMqUyQTy3 P+2xib6fSm5Ko/w6G+hnboE23Ct0iZzPE39gsWB0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727382AbfGDGkD (ORCPT ); Thu, 4 Jul 2019 02:40:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:48846 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725945AbfGDGkD (ORCPT ); Thu, 4 Jul 2019 02:40:03 -0400 Received: from devnote2 (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 97790216E3; Thu, 4 Jul 2019 06:40:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562222402; bh=EJ5pWcgs9Xg/Wu0hHSUeJaZ/LScLq5frs0oVc8rOuEw=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=1VwjjbPYPtcdZxvlVkd3X2pqjMCpKz9EgcBbvdAYwOs7Cw8cjeJpiao3CA30Jc4Kl OnK5PJN19O/H+xMg3lmsPjBLLtL70ozpUUh5E8IU2+oWlLfy4fLxiL2/db/RPHsWmO VcV7nNpLIJiUfTFpilhMgbSopdxG1JbICEaFcwe8= Date: Thu, 4 Jul 2019 15:39:58 +0900 From: Masami Hiramatsu To: Steven Rostedt , Masami Hiramatsu Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Tom Zanussi , Ravi Bangoria , Namhyung Kim , Arnaldo Carvalho de Melo Subject: Re: [PATCH v2 00/12] tracing/probe: Add multi-probes per event support Message-Id: <20190704153958.16a97c881aebbc5898b1264e@kernel.org> In-Reply-To: <156095682948.28024.14190188071338900568.stgit@devnote2> References: <156095682948.28024.14190188071338900568.stgit@devnote2> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Steve, Would you have any comment on this? Thank you, On Thu, 20 Jun 2019 00:07:09 +0900 Masami Hiramatsu wrote: > Hello, > > This is the 2nd version of multi-probes per event support on ftrace > and perf-tools. > > Previous version is here; > https://lkml.org/lkml/2019/5/31/573 > > >From this version, I omitted first 9 patches which has been picked > to Steve's tree. > In this version, I've fixed some bugs and hardened some unexpected > error cases according to Steve's comment. > Here are changes in this version: > > - [1/12] This have below changes. > - Warn if the primary trace_probe does not exist. > - Fix enable_trace_kprobe() to not return error if the any probes > are "gone" state. If all probes have gone or any other error > reason, the event can not be enabled and return error. > - Fix trace_probe_enable() to roll back all enabled uprobe if > any one of uprobe is failed to enable. > - [7/12] Swap the checking order of filename for avoiding unexpected > memory access. > > > ==== > For trace-event, we can insert same trace-event on several places > on the code, and those can record similar information as a same event > with same format. > > This series implements similar feature on probe-event. Since the probe > event is based on the compiled binary, sometimes we find that the target > source line is complied into several different addresses, e.g. inlined > function, unrolled loop, etc. In those cases, it is useful to put a > same probe-event on different addresses. > > With this series, we can append multi probes on one event as below > > # echo p:testevent _do_fork r1=%ax r2=%dx > kprobe_events > # echo p:testevent fork_idle r1=%ax r2=%cx >> kprobe_events > # kprobe_events > p:kprobes/testevent _do_fork r1=%ax r2=%dx > p:kprobes/testevent fork_idle r1=%ax r2=%cx > > This means testevent is hit on both of _do_fork and fork_idle. > As you can see, the appended event must have same number of arguments > and those must have same 'type' and 'name' as original one. This is like > a function signature, it checks whether the appending event has the same > type and name of event arguments and same probe type, but doesn't care > about the assignment. > > So, below appending commands will be rejected. > > # echo p:testevent _do_fork r1=%ax r2=%dx > kprobe_events > # echo p:testevent fork_idle r1=%ax >> kprobe_events > (No 2nd argument) > # echo p:testevent fork_idle r1=%ax r2=%ax:x8 >> kprobe_events > (The type of 2nd argument is different) > > If one inlined code has an argument on a register, but another > inlined code has fixed value (as a result of optimization), > you can also specify the fixed immediate value, e.g. > > # echo p:testevent _do_fork r1=%ax r2=%dx > kprobe_events > # echo p:testevent fork_idle r1=%ax r2=\1 >> kprobe_events > > > Thank you, > > --- > > Masami Hiramatsu (12): > tracing/probe: Split trace_event related data from trace_probe > tracing/dynevent: Delete all matched events > tracing/dynevent: Pass extra arguments to match operation > tracing/kprobe: Add multi-probe per event support > tracing/uprobe: Add multi-probe per uprobe event support > tracing/kprobe: Add per-probe delete from event > tracing/uprobe: Add per-probe delete from event > tracing/probe: Add immediate parameter support > tracing/probe: Add immediate string parameter support > selftests/ftrace: Add a testcase for kprobe multiprobe event > selftests/ftrace: Add syntax error test for immediates > selftests/ftrace: Add syntax error test for multiprobe > > > Documentation/trace/kprobetrace.rst | 1 > Documentation/trace/uprobetracer.rst | 1 > kernel/trace/trace.c | 8 - > kernel/trace/trace_dynevent.c | 10 + > kernel/trace/trace_dynevent.h | 7 - > kernel/trace/trace_events_hist.c | 4 > kernel/trace/trace_kprobe.c | 241 ++++++++++++++---- > kernel/trace/trace_probe.c | 176 +++++++++++-- > kernel/trace/trace_probe.h | 67 ++++- > kernel/trace/trace_uprobe.c | 263 +++++++++++++++----- > tools/testing/selftests/ftrace/test.d/functions | 2 > .../ftrace/test.d/kprobe/kprobe_multiprobe.tc | 35 +++ > .../ftrace/test.d/kprobe/kprobe_syntax_errors.tc | 15 + > 13 files changed, 665 insertions(+), 165 deletions(-) > create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/kprobe_multiprobe.tc > > -- > Masami Hiramatsu (Linaro) -- Masami Hiramatsu