From patchwork Thu Aug 19 04:13:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 12446225 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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 8EE0AC4338F for ; Thu, 19 Aug 2021 04:18:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 79D4C6112D for ; Thu, 19 Aug 2021 04:18:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229706AbhHSETS (ORCPT ); Thu, 19 Aug 2021 00:19:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:48914 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229505AbhHSETS (ORCPT ); Thu, 19 Aug 2021 00:19:18 -0400 Received: from gandalf.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 6634D61100; Thu, 19 Aug 2021 04:18:42 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.94.2) (envelope-from ) id 1mGZVp-004dvT-AY; Thu, 19 Aug 2021 00:18:41 -0400 Message-ID: <20210819041841.159849933@goodmis.org> User-Agent: quilt/0.66 Date: Thu, 19 Aug 2021 00:13:22 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-devel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Masami Hiramatsu , "Tzvetomir Stoyanov" , Tom Zanussi Subject: [PATCH v7 01/10] tracing: Add DYNAMIC flag for dynamic events References: <20210819041321.105110033@goodmis.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org From: "Steven Rostedt (VMware)" To differentiate between static and dynamic events, add a new flag DYNAMIC to the event flags that all dynamic events have set. This will allow to differentiate when attaching to a dynamic event from a static event. Static events have a mod pointer that references the module they were created in (or NULL for core kernel). This can be incremented when the event has something attached to it. But there exists no such mechanism for dynamic events. This is dangerous as the dynamic events may now disappear without the "attachment" knowing that it no longer exists. To enforce the dynamic flag, change dyn_event_add() to pass the event that is being created such that it can set the DYNAMIC flag of the event. This helps make sure that no location that creates a dynamic event misses setting this flag. Link: https://lore.kernel.org/linux-trace-devel/20210813004448.51c7de69ce432d338f4d226b@kernel.org/ Link: https://lkml.kernel.org/r/20210817035026.936958254@goodmis.org Suggested-by: Masami Hiramatsu Acked-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- include/linux/trace_events.h | 3 +++ kernel/trace/trace_dynevent.h | 4 +++- kernel/trace/trace_events_synth.c | 2 +- kernel/trace/trace_kprobe.c | 4 ++-- kernel/trace/trace_uprobe.c | 4 ++-- 5 files changed, 11 insertions(+), 6 deletions(-) diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index ad413b382a3c..53c9dffd87fd 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -310,6 +310,7 @@ enum { TRACE_EVENT_FL_NO_SET_FILTER_BIT, TRACE_EVENT_FL_IGNORE_ENABLE_BIT, TRACE_EVENT_FL_TRACEPOINT_BIT, + TRACE_EVENT_FL_DYNAMIC_BIT, TRACE_EVENT_FL_KPROBE_BIT, TRACE_EVENT_FL_UPROBE_BIT, }; @@ -321,6 +322,7 @@ enum { * NO_SET_FILTER - Set when filter has error and is to be ignored * IGNORE_ENABLE - For trace internal events, do not enable with debugfs file * TRACEPOINT - Event is a tracepoint + * DYNAMIC - Event is a dynamic event (created at run time) * KPROBE - Event is a kprobe * UPROBE - Event is a uprobe */ @@ -330,6 +332,7 @@ enum { TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT), TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT), TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT), + TRACE_EVENT_FL_DYNAMIC = (1 << TRACE_EVENT_FL_DYNAMIC_BIT), TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT), TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT), }; diff --git a/kernel/trace/trace_dynevent.h b/kernel/trace/trace_dynevent.h index 7754936b57ee..936477a111d3 100644 --- a/kernel/trace/trace_dynevent.h +++ b/kernel/trace/trace_dynevent.h @@ -76,13 +76,15 @@ int dyn_event_init(struct dyn_event *ev, struct dyn_event_operations *ops) return 0; } -static inline int dyn_event_add(struct dyn_event *ev) +static inline int dyn_event_add(struct dyn_event *ev, + struct trace_event_call *call) { lockdep_assert_held(&event_mutex); if (!ev || !ev->ops) return -EINVAL; + call->flags |= TRACE_EVENT_FL_DYNAMIC; list_add_tail(&ev->list, &dyn_event_list); return 0; } diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index 9315fc03e303..f4f5489e1e28 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -1298,7 +1298,7 @@ static int __create_synth_event(const char *name, const char *raw_fields) } ret = register_synth_event(event); if (!ret) - dyn_event_add(&event->devent); + dyn_event_add(&event->devent, &event->call); else free_synth_event(event); out: diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index ea6178cb5e33..bfef43bfce37 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -618,7 +618,7 @@ static int append_trace_kprobe(struct trace_kprobe *tk, struct trace_kprobe *to) if (ret) trace_probe_unlink(&tk->tp); else - dyn_event_add(&tk->devent); + dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp)); return ret; } @@ -661,7 +661,7 @@ static int register_trace_kprobe(struct trace_kprobe *tk) if (ret < 0) unregister_kprobe_event(tk); else - dyn_event_add(&tk->devent); + dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp)); end: mutex_unlock(&event_mutex); diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 9b50869a5ddb..50eca53b8d22 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -455,7 +455,7 @@ static int append_trace_uprobe(struct trace_uprobe *tu, struct trace_uprobe *to) /* Append to existing event */ ret = trace_probe_append(&tu->tp, &to->tp); if (!ret) - dyn_event_add(&tu->devent); + dyn_event_add(&tu->devent, trace_probe_event_call(&tu->tp)); return ret; } @@ -518,7 +518,7 @@ static int register_trace_uprobe(struct trace_uprobe *tu) goto end; } - dyn_event_add(&tu->devent); + dyn_event_add(&tu->devent, trace_probe_event_call(&tu->tp)); end: mutex_unlock(&event_mutex);