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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 D8722C31E5B for ; Tue, 18 Jun 2019 01:56:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B787D2084B for ; Tue, 18 Jun 2019 01:56:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727765AbfFRB4r (ORCPT ); Mon, 17 Jun 2019 21:56:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:33912 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726656AbfFRB4r (ORCPT ); Mon, 17 Jun 2019 21:56:47 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (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 2A8462080C; Tue, 18 Jun 2019 01:56:45 +0000 (UTC) Date: Mon, 17 Jun 2019 21:56:43 -0400 From: Steven Rostedt To: Masami Hiramatsu Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Tom Zanussi , Ravi Bangoria , Namhyung Kim , Arnaldo Carvalho de Melo Subject: Re: [PATCH 10/21] tracing/probe: Split trace_event related data from trace_probe Message-ID: <20190617215643.05a33541@oasis.local.home> In-Reply-To: <155931589667.28323.6107724588059072406.stgit@devnote2> References: <155931578555.28323.16360245959211149678.stgit@devnote2> <155931589667.28323.6107724588059072406.stgit@devnote2> X-Mailer: Claws Mail 3.17.3 (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 On Sat, 1 Jun 2019 00:18:16 +0900 Masami Hiramatsu wrote: > Split the trace_event related data from trace_probe data structure > and introduce trace_probe_event data structure for its folder. > This trace_probe_event data structure can have multiple trace_probe. > > Signed-off-by: Masami Hiramatsu > --- > kernel/trace/trace_kprobe.c | 99 ++++++++++++++++++++++------------- > kernel/trace/trace_probe.c | 53 +++++++++++++------ > kernel/trace/trace_probe.h | 48 +++++++++++++---- > kernel/trace/trace_uprobe.c | 123 +++++++++++++++++++++++++++++-------------- > 4 files changed, 221 insertions(+), 102 deletions(-) > > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > index 9d483ad9bb6c..633edb88cd0e 100644 > --- a/kernel/trace/trace_kprobe.c > +++ b/kernel/trace/trace_kprobe.c > @@ -180,9 +180,17 @@ unsigned long trace_kprobe_address(struct trace_kprobe *tk) > return addr; > } > > +static nokprobe_inline struct trace_kprobe * > +trace_kprobe_primary_from_call(struct trace_event_call *call) > +{ > + struct trace_probe *tp = trace_probe_primary_from_call(call); > + > + return container_of(tp, struct trace_kprobe, tp); Hmm, is there a possibility that trace_probe_primary_from_call() may not have a primary? > +} > + > bool trace_kprobe_on_func_entry(struct trace_event_call *call) > { > - struct trace_kprobe *tk = (struct trace_kprobe *)call->data; > + struct trace_kprobe *tk = trace_kprobe_primary_from_call(call); > > return kprobe_on_func_entry(tk->rp.kp.addr, > tk->rp.kp.addr ? NULL : tk->rp.kp.symbol_name, > @@ -191,7 +199,7 @@ bool trace_kprobe_on_func_entry(struct trace_event_call *call) > > bool trace_kprobe_error_injectable(struct trace_event_call *call) > { > - struct trace_kprobe *tk = (struct trace_kprobe *)call->data; > + struct trace_kprobe *tk = trace_kprobe_primary_from_call(call); > > return within_error_injection_list(trace_kprobe_address(tk)); > } > @@ -295,28 +303,40 @@ static inline int __enable_trace_kprobe(struct trace_kprobe *tk) > * Enable trace_probe > * if the file is NULL, enable "perf" handler, or enable "trace" handler. > */ > -static int > -enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file) > +static int enable_trace_kprobe(struct trace_event_call *call, > + struct trace_event_file *file) > { > - bool enabled = trace_probe_is_enabled(&tk->tp); > - int ret = 0; > + struct trace_probe *pos, *tp = trace_probe_primary_from_call(call); > + struct trace_kprobe *tk; > + bool enabled = trace_probe_is_enabled(tp); > + int ret = 0, ecode; > > if (file) { > - ret = trace_probe_add_file(&tk->tp, file); > + ret = trace_probe_add_file(tp, file); > if (ret) > return ret; > } else > - trace_probe_set_flag(&tk->tp, TP_FLAG_PROFILE); > + trace_probe_set_flag(tp, TP_FLAG_PROFILE); > > if (enabled) > return 0; > > - ret = __enable_trace_kprobe(tk); > - if (ret) { > + enabled = false; > + list_for_each_entry(pos, trace_probe_probe_list(tp), list) { > + tk = container_of(pos, struct trace_kprobe, tp); > + ecode = __enable_trace_kprobe(tk); > + if (ecode) > + ret = ecode; /* Save the last error code */ > + else > + enabled = true; So, if we have some enabled but return an error code, what should a caller think of that? Wouldn't it be an inconsistent state? -- Steve > + } > + > + if (!enabled) { > + /* No probe is enabled. Roll back */ > if (file) > - trace_probe_remove_file(&tk->tp, file); > + trace_probe_remove_file(tp, file); > else > - trace_probe_clear_flag(&tk->tp, TP_FLAG_PROFILE); > + trace_probe_clear_flag(tp, TP_FLAG_PROFILE); > } > > > +static inline struct trace_probe_event * > +trace_probe_event_from_call(struct trace_event_call *event_call) > +{ > + return container_of(event_call, struct trace_probe_event, call); > +} > + > +static inline struct trace_probe * > +trace_probe_primary_from_call(struct trace_event_call *call) > +{ > + struct trace_probe_event *tpe = trace_probe_event_from_call(call); > + > + return list_first_entry(&tpe->probes, struct trace_probe, list); > +} > + > +static inline struct list_head *trace_probe_probe_list(struct trace_probe *tp) > +{ > + return &tp->event->probes; > } >